@font-face {
  font-family: 'cMath Display Fallback';
  src: local('Arial Bold'), local('Arial-BoldMT'), local('Arial');
  font-weight: 500 800;
  size-adjust: 105.57%; ascent-override: 94.72%; descent-override: 25.10%; line-gap-override: 0%;
}
@font-face {
  font-family: 'cMath Body Fallback';
  src: local('Arial'), local('ArialMT');
  font-weight: 400 700;
  size-adjust: 104.92%; ascent-override: 98.93%; descent-override: 21.16%; line-gap-override: 0%;
}

:root {
  
  --c-hong-sen: #C02991;       
  --c-hong-sen-glow: rgba(192, 41, 145, 0.35);
  --c-tim: #6A2D78;            
  --c-tim-dam: #4E2E6F;        
  --c-navy: #112B49;           
  --c-teal: #1F5761;           
  --c-cam: #F07935;            
  --c-cam-glow: rgba(240, 121, 53, 0.35);

  
  --c-nhan: #7B2E86;           
  --c-nhan-dam: #5E2168;       
  --c-nhan-nhe: #F4EAF7;       
  --c-xanh-ok: #1B6E62;        
  --c-do: #C42B1C;             
  --c-vang: #9D5D00;           

  
  --c-den-xanh: #1B6E62;       
  --c-den-vang: #9D5D00;       
  --c-den-do: #C42B1C;         
  --c-den-tim: #C02991;        

  
  
  --gradient-logo: linear-gradient(90deg, #C02991 0%, #6A2D78 55%, #112B49 100%);
  --gradient-logo-angle: linear-gradient(135deg, #C02991 0%, #6A2D78 55%, #112B49 100%);
  --gradient-spark: linear-gradient(135deg, #F07935 0%, #C02991 55%, #6A2D78 100%);
  --gradient-teal: linear-gradient(135deg, #1F5761 0%, #10707D 100%);
  --gradient-btn: linear-gradient(135deg, #C02991 0%, #7B2E86 100%);
  --gradient-btn-hover: linear-gradient(135deg, #D436A5 0%, #C02991 100%);
  --gradient-gold: linear-gradient(135deg, #F07935 0%, #E66A22 100%);

  
  --font-display: 'Be Vietnam Pro','cMath Display Fallback', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-body: 'Plus Jakarta Sans','cMath Body Fallback', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, monospace;

  
  --radius-xs: 6px;
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-full: 9999px;

  --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.28s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-bounce: 0.45s cubic-bezier(0.34, 1.56, 0.64, 1);

  
  --bg-primary: #F4F4F8;       
  --bg-secondary: #FFFFFF;     
  --bg-card: #FFFFFF;          
  --bg-card-hover: #FFFFFF;
  --bg-glass: rgba(255, 255, 255, 0.95);
  --bg-subtle: #EDEBF4;
  --border-subtle: #D8D4E5;    
  --border-glass: rgba(216, 212, 229, 0.95);
  --border-focus: #C02991;

  --text-main: #0B0E23;        
  --text-muted: #282B44;       
  --text-dim: #454866;         

  --shadow-subtle: 0 4px 18px -2px rgba(11, 14, 35, 0.08);
  --shadow-card: 0 4px 20px -2px rgba(11, 14, 35, 0.08), 0 1px 3px rgba(11, 14, 35, 0.05);
  --shadow-card-hover: 0 12px 32px -4px rgba(106, 45, 120, 0.16), 0 2px 8px rgba(11, 14, 35, 0.08);
  --shadow-glow: 0 0 35px -5px rgba(192, 41, 145, 0.22);
  --shadow-cmate: 0 14px 40px -8px rgba(11, 14, 35, 0.18), 0 0 25px -4px rgba(192, 41, 145, 0.25);

  --btn-secondary-bg: #EAE7F0;
  --btn-secondary-hover: #DED9E8;
  --btn-secondary-text: #0B0E23;

  
  --c-primary: var(--c-hong-sen);
  --c-primary-glow: var(--c-hong-sen-glow);
  --c-secondary: var(--c-tim);
  --c-accent: var(--c-cam);
  --c-accent-glow: var(--c-cam-glow);
  --c-emerald: #1B6E62;
  --border-card: var(--border-subtle);
  --brand-crimson: var(--c-hong-sen);
  --brand-purple: var(--c-tim);
  --brand-deep-violet: var(--c-tim-dam);
  --brand-navy: var(--c-navy);
  --brand-teal: var(--c-teal);
  --brand-orange: var(--c-cam);
  --brand-gradient: var(--gradient-logo);
  --light-green: var(--c-den-xanh);
  --light-amber: var(--c-den-vang);
  --light-red: var(--c-den-do);
  --light-purple: var(--c-den-tim);
}


[data-theme="dark"] {
  --bg-primary: #151525;       
  --bg-secondary: #1F1F33;     
  --bg-card: #292942;          
  --bg-card-hover: #333352;
  --bg-glass: rgba(33, 33, 53, 0.92);
  --bg-subtle: #1F1F33;
  --border-subtle: #4D4A6E;    
  --border-glass: rgba(77, 74, 110, 0.9);
  --border-focus: #C88AD4;

  --text-main: #FFFFFF;        
  --text-muted: #E2E0EE;       
  --text-dim: #BEBAD2;         

  --c-nhan: #C88AD4;           
  --c-nhan-dam: #D9A0E3;
  --c-nhan-nhe: #3B2E52;
  --c-xanh-ok: #32C4AE;
  --c-do: #FF7D6E;
  --c-vang: #E8B446;

  --shadow-subtle: 0 4px 20px -2px rgba(0, 0, 0, 0.55);
  --shadow-card: 0 6px 24px -2px rgba(0, 0, 0, 0.65);
  --shadow-card-hover: 0 14px 36px -4px rgba(0, 0, 0, 0.8), 0 0 25px rgba(192, 41, 145, 0.3);
  --shadow-glow: 0 0 35px -5px rgba(200, 138, 212, 0.35);
  --shadow-cmate: 0 16px 45px -8px rgba(0, 0, 0, 0.85), 0 0 30px rgba(192, 41, 145, 0.4);

  --btn-secondary-bg: #3E3B57;
  --btn-secondary-hover: #504D70;
  --btn-secondary-text: #FFFFFF;

  --c-emerald: #32C4AE;
}



*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-body);
  background-color: var(--bg-primary);
  color: var(--text-main);
  line-height: 1.65;
  overflow-x: hidden;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color var(--transition-smooth), color var(--transition-smooth);
}


body::before {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background-image: 
    radial-gradient(circle at 1px 1px, rgba(106, 45, 120, 0.055) 1px, transparent 0),
    linear-gradient(to right, rgba(228, 225, 236, 0.22) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(228, 225, 236, 0.22) 1px, transparent 1px);
  background-size: 32px 32px, 128px 128px, 128px 128px;
  background-position: center top;
}

[data-theme="dark"] body::before {
  background-image: 
    radial-gradient(circle at 1px 1px, rgba(192, 41, 145, 0.08) 1px, transparent 0),
    linear-gradient(to right, rgba(62, 60, 82, 0.22) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(62, 60, 82, 0.22) 1px, transparent 1px);
}


.ambient-bg {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.glow-orb-1 {
  position: absolute;
  top: -12%;
  left: 20%;
  width: 550px;
  height: 550px;
  background: radial-gradient(circle, rgba(192, 41, 145, 0.12) 0%, rgba(192, 41, 145, 0) 70%);
  border-radius: 50%;
  filter: blur(80px);
}

.glow-orb-2 {
  position: absolute;
  top: 35%;
  right: -10%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(106, 45, 120, 0.1) 0%, rgba(106, 45, 120, 0) 70%);
  border-radius: 50%;
  filter: blur(90px);
}

.glow-orb-3 {
  position: absolute;
  bottom: 5%;
  left: -5%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(240, 121, 53, 0.08) 0%, rgba(240, 121, 53, 0) 70%);
  border-radius: 50%;
  filter: blur(80px);
}

[data-theme="dark"] .glow-orb-1 {
  background: radial-gradient(circle, rgba(192, 41, 145, 0.18) 0%, rgba(192, 41, 145, 0) 70%);
}
[data-theme="dark"] .glow-orb-2 {
  background: radial-gradient(circle, rgba(106, 45, 120, 0.16) 0%, rgba(106, 45, 120, 0) 70%);
}
[data-theme="dark"] .glow-orb-3 {
  background: radial-gradient(circle, rgba(240, 121, 53, 0.12) 0%, rgba(240, 121, 53, 0) 70%);
}

.container {
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 1.5rem;
  position: relative;
  z-index: 1;
}



h1, h2, h3, h4, h5, .brand-font {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-main);
  letter-spacing: -0.015em;
}

.text-gradient {
  background: var(--gradient-spark);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.text-logo-gradient {
  background: var(--gradient-logo);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.text-gold {
  background: var(--gradient-gold);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}



.logo-gradient-bar {
  width: 100%;
  height: 3.5px;
  background: var(--gradient-logo);
  position: relative;
  overflow: hidden;
}

.logo-gradient-bar::after {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 50%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.6), transparent);
  animation: shineGradient 4s infinite linear;
}

@keyframes shineGradient {
  0% { left: -50%; }
  100% { left: 150%; }
}



.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
  padding: 0;
  transition: all var(--transition-smooth);
  box-shadow: 0 4px 20px -5px rgba(17, 43, 73, 0.05);
}

.nav-wrapper {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 1.5rem;
}


.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  text-decoration: none;
  color: var(--text-main);
}

.brand-logo-img {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  object-fit: cover;
  background: #ffffff;
  padding: 2px;
  box-shadow: 0 2px 10px rgba(17, 43, 73, 0.12), 0 0 16px var(--c-hong-sen-glow);
  border: 1.5px solid var(--border-subtle);
  transition: transform var(--transition-smooth), box-shadow var(--transition-smooth);
}

.brand-logo:hover .brand-logo-img {
  transform: rotate(6deg) scale(1.06);
  box-shadow: 0 4px 18px rgba(192, 41, 145, 0.5), 0 0 12px var(--c-cam-glow);
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.brand-title {
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.1;
  color: var(--text-main);
}

.brand-domain {
  color: var(--c-cam);
}

.brand-tagline {
  font-size: 0.72rem;
  color: var(--text-muted);
  font-weight: 600;
  letter-spacing: 0.04em;
  margin-top: 1px;
}


.nav-links {
  display: flex;
  align-items: center;
  gap: 1.8rem;
  list-style: none;
}

.nav-link {
  text-decoration: none;
  color: var(--text-muted);
  font-weight: 600;
  font-size: 0.95rem;
  transition: color var(--transition-fast);
  position: relative;
  padding: 0.35rem 0;
}

.nav-link:hover, .nav-link.active {
  color: var(--c-nhan);
}

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2.5px;
  background: var(--gradient-logo);
  border-radius: var(--radius-full);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.8rem;
}


.theme-toggle-btn {
  background: var(--btn-secondary-bg);
  border: 1px solid var(--border-subtle);
  color: var(--text-muted);
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.theme-toggle-btn:hover {
  background: var(--c-nhan-nhe);
  color: var(--c-nhan);
  border-color: var(--c-nhan);
  transform: rotate(15deg);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: var(--text-main);
  font-size: 1.5rem;
  cursor: pointer;
}



.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.92rem;
  padding: 0.72rem 1.6rem;
  border-radius: var(--radius-full);
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.btn-primary {
  background: var(--gradient-btn);
  color: #ffffff;
  box-shadow: 0 4px 16px rgba(192, 41, 145, 0.35);
}

.btn-primary:hover {
  background: var(--gradient-btn-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 22px rgba(192, 41, 145, 0.55);
}

.btn-secondary {
  background: var(--btn-secondary-bg);
  color: var(--btn-secondary-text);
  border-color: var(--border-subtle);
}

.btn-secondary:hover {
  background: var(--btn-secondary-hover);
  transform: translateY(-2px);
}

.btn-gold, .btn-accent {
  background: var(--gradient-spark);
  color: #ffffff;
  box-shadow: 0 4px 16px var(--c-cam-glow);
}

.btn-gold:hover, .btn-accent:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 22px rgba(240, 121, 53, 0.55);
}

.btn-outline {
  background: var(--bg-card);
  border: 1.5px solid var(--border-subtle);
  color: var(--text-main);
  backdrop-filter: blur(10px);
}

.btn-outline:hover {
  border-color: var(--c-nhan);
  color: var(--c-nhan);
  background: var(--c-nhan-nhe);
  transform: translateY(-2px);
}

.btn:focus-visible {
  outline: 3px solid var(--c-cam);
  outline-offset: 2px;
}



.glass-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
  transition: transform var(--transition-fast), border-color var(--transition-fast), box-shadow var(--transition-fast);
  position: relative;
}

.glass-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 28px rgba(0, 0, 0, 0.06), 0 2px 8px rgba(192, 41, 145, 0.08);
  border-color: rgba(192, 41, 145, 0.18);
}


.card-with-gradient-bar {
  overflow: hidden;
}

.card-with-gradient-bar::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-logo);
}


.card-tai-lieu:hover {
  border-color: var(--c-nhan);
  box-shadow: var(--shadow-card-hover);
}



.hero-section {
  padding: 4.5rem 0 3.8rem;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 3.5rem;
  align-items: center;
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--c-nhan-nhe);
  border: 1px solid rgba(123, 46, 134, 0.25);
  padding: 0.4rem 1rem;
  border-radius: var(--radius-full);
  color: var(--c-nhan);
  font-size: 0.85rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
}

.hero-title {
  font-size: 3.3rem;
  line-height: 1.16;
  margin-bottom: 1.3rem;
  letter-spacing: -0.03em;
}

.hero-subtitle {
  font-size: 1.12rem;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 2.2rem;
}

.hero-cta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 2.5rem;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  border-top: 1px solid var(--border-subtle);
  padding-top: 2rem;
}

.stat-item h3 {
  font-size: 2rem;
  font-weight: 800;
  color: var(--c-cam);
  margin-bottom: 0.2rem;
}

.stat-item p {
  font-size: 0.92rem;
  color: var(--text-muted);
  font-weight: 600;
}


.hero-visual {
  position: relative;
}

.ecosystem-card {
  padding: 2.2rem;
  position: relative;
  overflow: hidden;
  border-color: rgba(192, 41, 145, 0.25);
}

.ecosystem-badge {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--c-nhan);
  background: var(--c-nhan-nhe);
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-full);
  letter-spacing: 0.06em;
  margin-bottom: 1rem;
}

.ecosystem-flow {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-top: 1.2rem;
}

.flow-node {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 0.95rem 1.2rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.flow-node:hover {
  background: var(--bg-card);
  border-color: var(--c-hong-sen);
  transform: translateX(4px);
  box-shadow: 0 4px 15px rgba(192, 41, 145, 0.12);
}

.flow-icon {
  font-size: 1.4rem;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.flow-info h4 {
  font-size: 0.98rem;
  margin-bottom: 0.2rem;
}

.flow-info p {
  font-size: 0.82rem;
  color: var(--text-muted);
}



.section-header {
  text-align: center;
  max-width: 880px;
  margin: 0 auto 3.5rem;
}

.section-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--c-nhan);
  background: var(--c-nhan-nhe);
  border: 1px solid rgba(192, 41, 145, 0.24);
  padding: 0.3rem 0.95rem;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.8rem;
  box-shadow: 0 2px 10px rgba(192, 41, 145, 0.08);
}

.section-pill::before {
  content: '';
  width: 6px;
  height: 6px;
  background: var(--c-cam);
  border-radius: 1.5px;
  transform: rotate(45deg);
  box-shadow: 0 0 6px var(--c-cam-glow);
  flex-shrink: 0;
}

.section-title {
  font-size: 2.35rem;
  margin-bottom: 0.9rem;
  text-wrap: balance;
}

.section-subtitle {
  color: var(--text-muted);
  font-size: 1.05rem;
  line-height: 1.7;
  text-wrap: balance;
}



.text-nowrap {
  white-space: nowrap;
}


.cum-triet-ly {
  white-space: nowrap;
  display: inline-block;
}


.br-desktop {
  display: inline;
}

@media (max-width: 768px) {
  .br-desktop {
    display: none;
  }
  .cum-triet-ly {
    white-space: normal;
  }
}



.pillars-section {
  padding: 4.5rem 0;
}

.smart-steps-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  margin: 2.5rem 0;
}

.smart-step-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.8rem;
  position: relative;
  transition: all var(--transition-smooth);
  box-shadow: var(--shadow-card);
}

.smart-step-card:hover {
  transform: translateY(-4px);
  border-color: var(--c-hong-sen);
  box-shadow: var(--shadow-card-hover);
}

.smart-step-num {
  font-size: 2.4rem;
  font-weight: 800;
  font-family: var(--font-display);
  background: var(--gradient-spark);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1;
  margin-bottom: 0.8rem;
}

.smart-step-title {
  font-size: 1.12rem;
  font-weight: 700;
  margin-bottom: 0.6rem;
  color: var(--text-main);
}

.smart-step-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.6;
}



.pillar-badge {
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.28rem 0.7rem;
  border-radius: var(--radius-full);
  display: inline-block;
}

.badge-purple {
  background: var(--c-nhan-nhe);
  color: var(--c-nhan);
  border: 1px solid rgba(123, 46, 134, 0.25);
}

.badge-teal {
  background: rgba(31, 87, 97, 0.12);
  color: #1F5761;
  border: 1px solid rgba(31, 87, 97, 0.25);
}

[data-theme="dark"] .badge-teal {
  background: rgba(31, 87, 97, 0.3);
  color: #4DB3C4;
}

.badge-emerald {
  background: rgba(27, 110, 98, 0.12);
  color: var(--c-xanh-ok);
  border: 1px solid rgba(27, 110, 98, 0.25);
}

.badge-amber {
  background: rgba(240, 121, 53, 0.12);
  color: var(--c-cam);
  border: 1px solid rgba(240, 121, 53, 0.25);
}


.den-pedagogy {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.82rem;
  font-weight: 700;
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius-full);
}

.den-xanh { background: rgba(27, 110, 98, 0.12); color: #1B6E62; border: 1px solid rgba(27, 110, 98, 0.3); }
.den-vang { background: rgba(157, 93, 0, 0.12); color: #9D5D00; border: 1px solid rgba(157, 93, 0, 0.3); }
.den-do   { background: rgba(196, 43, 28, 0.12); color: #C42B1C; border: 1px solid rgba(196, 43, 28, 0.3); }
.den-tim  { background: rgba(192, 41, 145, 0.12); color: #C02991; border: 1px solid rgba(192, 41, 145, 0.3); }



.roadmap-section {
  padding: 4.5rem 0;
}

.roadmap-tabs {
  display: flex;
  justify-content: center;
  gap: 0.8rem;
  margin-bottom: 2.8rem;
  flex-wrap: wrap;
}

.tab-btn {
  padding: 0.65rem 1.4rem;
  border-radius: var(--radius-full);
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  color: var(--text-muted);
  font-weight: 600;
  font-size: 0.92rem;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.tab-btn:hover {
  border-color: var(--c-nhan);
  color: var(--c-nhan);
  background: var(--c-nhan-nhe);
}

.tab-btn.active {
  background: var(--gradient-btn);
  color: #fff;
  border-color: transparent;
  box-shadow: 0 4px 16px rgba(192, 41, 145, 0.35);
}

.roadmap-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.course-card {
  padding: 2.2rem;
  display: flex;
  flex-direction: column;
}

.course-level {
  font-size: 0.75rem;
  font-weight: 800;
  text-transform: uppercase;
  color: var(--c-cam);
  letter-spacing: 0.05em;
  margin-bottom: 0.8rem;
}

.course-name {
  font-size: 1.35rem;
  margin-bottom: 0.8rem;
}

.course-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  line-height: 1.65;
}

.course-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 1.8rem;
}

.course-tag {
  font-size: 0.75rem;
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius-sm);
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  color: var(--text-muted);
  font-weight: 500;
}



#cmate-widget-root {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  pointer-events: none;
}

#cmate-widget-root > * {
  pointer-events: auto;
}


.cmate-speech-bubble {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid rgba(192, 41, 145, 0.35);
  border-radius: var(--radius-lg);
  padding: 1.1rem 1.3rem;
  max-width: 320px;
  margin-bottom: 14px;
  box-shadow: var(--shadow-cmate);
  position: relative;
  transform-origin: bottom right;
  animation: cmatePopIn 0.4s var(--transition-bounce);
  transition: opacity 0.5s ease, transform 0.5s ease, visibility 0.5s;
}

.cmate-speech-bubble.hidden-5s {
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px) scale(0.92);
  pointer-events: none;
}


.cmate-progress-track {
  width: 100%;
  height: 3px;
  background: var(--bg-secondary);
  border-radius: var(--radius-full);
  margin-bottom: 0.8rem;
  overflow: hidden;
}

.cmate-progress-fill {
  height: 100%;
  width: 100%;
  background: var(--gradient-spark);
  border-radius: var(--radius-full);
  animation: countdown5s 5s linear forwards;
}

.cmate-speech-bubble:hover .cmate-progress-fill {
  animation-play-state: paused;
}

@keyframes countdown5s {
  from { width: 100%; }
  to { width: 0%; }
}

.cmate-bubble-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.5rem;
}

.cmate-bubble-title {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--c-nhan);
}

.cmate-bubble-close {
  background: none;
  border: none;
  color: var(--text-dim);
  font-size: 1.1rem;
  cursor: pointer;
  line-height: 1;
}

.cmate-bubble-close:hover {
  color: var(--text-main);
}

.cmate-bubble-text {
  font-size: 0.86rem;
  color: var(--text-main);
  line-height: 1.5;
  margin-bottom: 0.8rem;
}

.cmate-bubble-actions {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.cmate-chip-btn {
  font-size: 0.75rem;
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-full);
  background: var(--c-nhan-nhe);
  border: 1px solid rgba(123, 46, 134, 0.25);
  color: var(--c-nhan);
  cursor: pointer;
  font-weight: 600;
  transition: all var(--transition-fast);
}

.cmate-chip-btn:hover {
  background: var(--c-nhan);
  color: #fff;
}


.cmate-trigger-btn {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  background: var(--gradient-btn);
  border: 2px solid rgba(255, 255, 255, 0.85);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: 0 8px 25px rgba(192, 41, 145, 0.45), 0 0 15px var(--c-cam-glow);
  position: relative;
  transition: transform var(--transition-bounce), box-shadow var(--transition-fast);
}

.cmate-trigger-btn:hover {
  transform: scale(1.08) rotate(3deg);
  box-shadow: 0 10px 32px rgba(192, 41, 145, 0.65), 0 0 22px var(--c-cam-glow);
}

.cmate-badge-pulse {
  position: absolute;
  top: -2px;
  right: -2px;
  width: 15px;
  height: 15px;
  background: var(--c-xanh-ok);
  border-radius: 50%;
  border: 2px solid var(--bg-primary);
  animation: pulseGreen 2s infinite;
}


.cmate-modal {
  position: fixed;
  bottom: 96px;
  right: 24px;
  width: 410px;
  max-width: calc(100vw - 48px);
  height: 580px;
  max-height: calc(100vh - 120px);
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-cmate);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  z-index: 10000;
  transform-origin: bottom right;
  transition: all var(--transition-bounce);
  opacity: 0;
  visibility: hidden;
  transform: scale(0.9) translateY(20px);
}

.cmate-modal.active {
  opacity: 1;
  visibility: visible;
  transform: scale(1) translateY(0);
}

.cmate-modal-header {
  padding: 1rem 1.3rem;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.cmate-modal-title {
  display: flex;
  align-items: center;
  gap: 0.7rem;
}

.cmate-avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--gradient-spark);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 1rem;
  color: #fff;
  box-shadow: 0 2px 8px var(--c-cam-glow);
}

.cmate-modal-messages {
  flex-grow: 1;
  padding: 1.2rem;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  background: var(--bg-primary);
}

.cmate-msg {
  max-width: 85%;
  padding: 0.85rem 1.1rem;
  border-radius: var(--radius-md);
  font-size: 0.88rem;
  line-height: 1.55;
}

.cmate-msg-bot {
  align-self: flex-start;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  color: var(--text-main);
  border-bottom-left-radius: 4px;
  box-shadow: var(--shadow-subtle);
}

.cmate-msg-user {
  align-self: flex-end;
  background: var(--gradient-btn);
  color: #fff;
  border-bottom-right-radius: 4px;
  box-shadow: 0 4px 14px rgba(192, 41, 145, 0.35);
}

.cmate-modal-input-area {
  padding: 0.9rem 1.2rem;
  background: var(--bg-card);
  border-top: 1px solid var(--border-subtle);
  display: flex;
  gap: 0.6rem;
}

.cmate-input {
  flex-grow: 1;
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  padding: 0.7rem 1.2rem;
  color: var(--text-main);
  font-size: 0.9rem;
  outline: none;
  transition: border-color var(--transition-fast);
}

.cmate-input:focus {
  border-color: var(--c-nhan);
  box-shadow: 0 0 0 2px var(--c-nhan-nhe);
}

.cmate-send-btn {
  background: var(--gradient-btn);
  color: #fff;
  border: none;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform var(--transition-fast);
  box-shadow: 0 4px 12px rgba(192, 41, 145, 0.35);
}

.cmate-send-btn:hover {
  transform: scale(1.05);
}

@keyframes cmatePopIn {
  from { opacity: 0; transform: scale(0.8) translateY(20px); }
  to { opacity: 1; transform: scale(1) translateY(0); }
}

@keyframes pulseGreen {
  0% { box-shadow: 0 0 0 0 rgba(27, 110, 98, 0.7); }
  70% { box-shadow: 0 0 0 8px rgba(27, 110, 98, 0); }
  100% { box-shadow: 0 0 0 0 rgba(27, 110, 98, 0); }
}



.math-visual-wrapper {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  margin: 1.5rem 0;
  box-shadow: var(--shadow-card);
  position: relative;
  overflow: hidden;
  transition: all var(--transition-smooth);
}

.math-visual-wrapper:hover {
  border-color: var(--c-hong-sen);
  box-shadow: var(--shadow-card-hover);
}

.math-visual-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.2rem;
  flex-wrap: wrap;
  gap: 0.8rem;
  border-bottom: 1px solid var(--border-subtle);
  padding-bottom: 0.8rem;
}

.visual-title-box {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.visual-title-box strong {
  font-size: 1.05rem;
  color: var(--text-main);
}

.visual-badge {
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius-full);
  background: var(--c-nhan-nhe);
  color: var(--c-nhan);
  border: 1px solid rgba(123, 46, 134, 0.25);
}

.visual-canvas-area {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  padding: 1.5rem 1rem;
  border: 1px dashed var(--border-subtle);
  position: relative;
}

.visual-svg-stage {
  width: 100%;
  max-width: 760px;
  height: auto;
  overflow: visible;
}

.visual-controls-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  margin-top: 1.2rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border-subtle);
  flex-wrap: wrap;
  gap: 1rem;
}

.visual-slider-group {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  flex: 1;
  min-width: 260px;
}

.visual-slider-group label {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-muted);
  white-space: nowrap;
}

.visual-range-input {
  flex: 1;
  accent-color: var(--c-hong-sen);
  cursor: pointer;
}

.visual-value-badge {
  background: rgba(240, 121, 53, 0.12);
  color: var(--c-cam);
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-sm);
  font-weight: 700;
  font-size: 0.85rem;
}

.visual-action-btns {
  display: flex;
  gap: 0.5rem;
}

.visual-btn {
  background: var(--btn-secondary-bg);
  border: 1px solid var(--border-subtle);
  color: var(--text-main);
  padding: 0.4rem 0.85rem;
  border-radius: var(--radius-sm);
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  transition: all var(--transition-fast);
}

.visual-btn:hover {
  background: var(--c-nhan-nhe);
  border-color: var(--c-nhan);
  color: var(--c-nhan);
}

.visual-btn.active {
  background: var(--gradient-btn);
  color: #fff;
  border-color: transparent;
}


.katex {
  font-size: 1.15em !important;
  text-rendering: geometricPrecision;
  color: var(--text-main) !important;
  font-weight: 600;
}

.katex .mfrac .frac-line {
  border-bottom-width: 0.08em !important;
  border-color: currentColor !important;
}

.katex-display {
  margin: 1.2rem 0 !important;
  padding: 1rem 1.4rem !important;
  background: var(--bg-secondary);
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
  border-left: 4px solid var(--c-hong-sen);
  overflow-x: auto;
  overflow-y: hidden;
  color: var(--text-main) !important;
}



.compare-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border-subtle);
  margin: 2.5rem 0;
  box-shadow: var(--shadow-subtle);
}

.compare-table th, .compare-table td {
  padding: 1.2rem 1.5rem;
  text-align: left;
}

.compare-table th {
  background: var(--bg-secondary);
  font-size: 0.95rem;
  font-weight: 700;
  border-bottom: 1px solid var(--border-subtle);
}

.compare-table td {
  font-size: 0.9rem;
  line-height: 1.6;
  border-bottom: 1px solid var(--border-subtle);
  background: var(--bg-card);
}

.compare-table tr:last-child td {
  border-bottom: none;
}

.compare-bad {
  color: var(--text-dim);
  background: rgba(196, 43, 28, 0.03) !important;
}

.compare-good {
  color: var(--text-main);
  background: rgba(27, 110, 98, 0.04) !important;
  font-weight: 600;
}

.compare-highlight {
  color: var(--c-xanh-ok);
  font-weight: 700;
}

.form-group {
  margin-bottom: 1.2rem;
}

.form-label {
  display: block;
  font-size: 0.88rem;
  font-weight: 600;
  margin-bottom: 0.4rem;
  color: var(--text-main);
}

.form-input, .cmath-input {
  width: 100%;
  background: var(--bg-secondary);
  border: 1.5px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.75rem 1rem;
  font-size: 0.92rem;
  color: var(--text-main);
  outline: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-input:focus, .cmath-input:focus {
  border-color: var(--c-nhan);
  box-shadow: 0 0 0 3px var(--c-nhan-nhe);
}



.site-footer {
  margin-top: auto;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-subtle);
  padding: 4rem 0 2rem;
  position: relative;
}

.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-logo);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr repeat(3, 1fr);
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-top: 1rem;
  max-width: 330px;
  line-height: 1.7;
}

.footer-col h4 {
  font-size: 1rem;
  margin-bottom: 1.2rem;
  color: var(--text-main);
  position: relative;
  display: inline-block;
}

.footer-col h4::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 32px;
  height: 2.5px;
  background: var(--gradient-logo);
  border-radius: var(--radius-full);
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.7rem;
}

.footer-links a {
  text-decoration: none;
  color: var(--text-muted);
  font-size: 0.88rem;
  transition: color var(--transition-fast);
}

.footer-links a:hover {
  color: var(--c-nhan);
}

.footer-bottom {
  border-top: 1px solid var(--border-subtle);
  padding-top: 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.88rem;
  color: var(--text-muted);
  font-weight: 500;
  flex-wrap: wrap;
  gap: 1rem;
}




.logo-orbit-hub {
  position: relative;
  width: 100%;
  max-width: 440px;
  aspect-ratio: 1 / 1;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: center;
}


.orbit-track-outer {
  position: absolute;
  inset: 12px;
  border-radius: 50%;
  border: 1.5px dashed rgba(31, 87, 97, 0.4);
  animation: spinTrack 60s linear infinite;
  pointer-events: none;
}

[data-theme="dark"] .orbit-track-outer {
  border-color: rgba(77, 179, 196, 0.4);
}


.orbit-track-inner {
  position: absolute;
  inset: 56px;
  border-radius: 50%;
  padding: 2.5px;
  background: var(--gradient-logo);
  mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  animation: spinTrackReverse 40s linear infinite;
  box-shadow: 0 0 25px var(--c-hong-sen-glow);
  pointer-events: none;
}


.orbit-core {
  position: relative;
  z-index: 5;
  width: 140px;
  height: 140px;
  border-radius: 50%;
  background: var(--bg-card);
  padding: 8px;
  box-shadow: 0 12px 35px rgba(17, 43, 73, 0.16), 0 0 35px var(--c-hong-sen-glow);
  border: 2px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform var(--transition-bounce), box-shadow var(--transition-smooth);
}

.orbit-core:hover {
  transform: scale(1.08) rotate(4deg);
  box-shadow: 0 16px 45px rgba(192, 41, 145, 0.4), 0 0 28px var(--c-cam-glow);
}

.orbit-core-img {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  object-fit: cover;
}


.orbit-halo {
  position: absolute;
  inset: -15px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(192, 41, 145, 0.25) 0%, rgba(240, 121, 53, 0.1) 45%, transparent 70%);
  filter: blur(14px);
  z-index: 1;
  pointer-events: none;
  animation: pulseGlow 4s ease-in-out infinite alternate;
}


.orbit-satellite {
  position: absolute;
  z-index: 10;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.55rem 0.95rem;
  background: var(--bg-card);
  border: 1.5px solid var(--border-subtle);
  border-radius: var(--radius-full);
  box-shadow: var(--shadow-card);
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-main);
  backdrop-filter: blur(12px);
  white-space: nowrap;
  transition: transform var(--transition-fast), border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.orbit-satellite:hover {
  transform: translateY(-2px) scale(1.05);
  border-color: var(--c-hong-sen);
  box-shadow: var(--shadow-card-hover);
}

.sat-1 {
  top: 4%;
  right: -6%;
}
.sat-1 .sat-icon {
  background: var(--c-nhan-nhe);
  color: var(--c-nhan);
}

.sat-2 {
  bottom: 12%;
  right: -8%;
}
.sat-2 .sat-icon {
  background: rgba(31, 87, 97, 0.12);
  color: #1F5761;
}

.sat-3 {
  bottom: 6%;
  left: -8%;
}
.sat-3 .sat-icon {
  background: rgba(240, 121, 53, 0.12);
  color: var(--c-cam);
}

.sat-icon {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
}


.circuit-orange-pin {
  position: absolute;
  top: 22px;
  left: 36px;
  width: 14px;
  height: 14px;
  background: var(--c-cam);
  border-radius: 3px;
  box-shadow: 0 0 12px var(--c-cam-glow);
  z-index: 6;
  animation: pulseNode 2.5s infinite alternate;
}

@keyframes spinTrack {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@keyframes spinTrackReverse {
  from { transform: rotate(360deg); }
  to { transform: rotate(0deg); }
}

@keyframes pulseGlow {
  0% { transform: scale(0.92); opacity: 0.7; }
  100% { transform: scale(1.08); opacity: 1; }
}

@keyframes pulseNode {
  0% { transform: scale(0.9); box-shadow: 0 0 6px var(--c-cam-glow); }
  100% { transform: scale(1.2); box-shadow: 0 0 16px rgba(240, 121, 53, 0.7); }
}


.circuit-divider {
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  padding: 2.8rem 0;
  width: 100%;
}

.circuit-divider-line {
  height: 2px;
  width: 100%;
  max-width: 360px;
  background: linear-gradient(90deg, transparent, var(--border-subtle) 25%, var(--border-subtle) 75%, transparent);
  position: relative;
}

.circuit-divider-node {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 4px 14px;
  background: var(--bg-primary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--text-dim);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.circuit-divider-node::before {
  content: '';
  width: 8px;
  height: 8px;
  background: var(--c-cam);
  border-radius: 2px;
  box-shadow: 0 0 8px var(--c-cam-glow);
}


.circuit-card {
  position: relative;
  overflow: hidden;
}

.circuit-card::after {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 18px;
  height: 18px;
  background: linear-gradient(135deg, transparent 50%, var(--c-cam) 50%);
  border-top-right-radius: var(--radius-md);
  opacity: 0.9;
}

.circuit-badge-pin {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--c-nhan);
  background: var(--c-nhan-nhe);
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-full);
  border-left: 3px solid var(--c-cam);
}


.circuit-stream {
  position: relative;
  padding-left: 3.5rem;
  display: flex;
  flex-direction: column;
  gap: 2.5rem;
}

.circuit-stream::before {
  content: '';
  position: absolute;
  top: 35px;
  bottom: 35px;
  left: 20px;
  width: 3.5px;
  background: linear-gradient(180deg, #C02991 0%, #6A2D78 50%, #F07935 100%);
  border-radius: var(--radius-full);
  box-shadow: 0 0 10px rgba(192, 41, 145, 0.3);
}

.circuit-stream-node {
  position: relative;
}

.circuit-stream-badge {
  position: absolute;
  left: -3.5rem;
  top: 1.8rem;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--bg-card);
  border: 2px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 0.95rem;
  font-family: var(--font-display);
  box-shadow: 0 4px 15px rgba(17, 43, 73, 0.1);
  z-index: 2;
}

.node-active-1 .circuit-stream-badge { border-color: #C02991; color: #C02991; box-shadow: 0 0 16px var(--c-hong-sen-glow); }
.node-active-2 .circuit-stream-badge { border-color: #1F5761; color: #1F5761; box-shadow: 0 0 16px rgba(31, 87, 97, 0.35); }
.node-active-3 .circuit-stream-badge { border-color: #F07935; color: #F07935; box-shadow: 0 0 16px var(--c-cam-glow); }


.circuit-chip-card {
  position: relative;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 2.2rem;
  box-shadow: var(--shadow-card);
  transition: all var(--transition-smooth);
  overflow: hidden;
}

.circuit-chip-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-logo);
  opacity: 0.85;
}

.circuit-chip-card::after {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 22px;
  height: 22px;
  background: linear-gradient(135deg, transparent 50%, var(--c-cam) 50%);
  border-top-right-radius: var(--radius-lg);
  z-index: 2;
}

.circuit-chip-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-card-hover);
  border-color: rgba(192, 41, 145, 0.4);
}

.circuit-coord-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-family: var(--font-display);
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--text-dim);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 0.6rem;
}

.circuit-coord-tag::before {
  content: '';
  display: inline-block;
  width: 7px;
  height: 7px;
  background: var(--c-cam);
  border-radius: 1.5px;
}


.student-radar-container {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 2rem;
  align-items: center;
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 2rem;
  margin-top: 1.5rem;
  position: relative;
  overflow: hidden;
}

.student-radar-container::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  width: 4px;
  background: var(--gradient-logo);
}

.radar-chart-box {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.radar-svg {
  width: 100%;
  max-width: 280px;
  height: auto;
  filter: drop-shadow(0 4px 12px rgba(192, 41, 145, 0.15));
}

.radar-metrics-list {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.radar-metric-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.radar-metric-label {
  font-size: 0.86rem;
  font-weight: 600;
  color: var(--text-main);
  min-width: 140px;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.radar-progress-bar {
  flex: 1;
  height: 7px;
  background: var(--border-subtle);
  border-radius: var(--radius-full);
  overflow: hidden;
  position: relative;
}

.radar-progress-fill {
  height: 100%;
  border-radius: var(--radius-full);
  transition: width 0.8s ease-out;
}

.fill-sen { background: linear-gradient(90deg, #C02991, #6A2D78); }
.fill-teal { background: linear-gradient(90deg, #1F5761, #1B6E62); }
.fill-cam { background: linear-gradient(90deg, #F07935, #E56820); }
.fill-purple { background: linear-gradient(90deg, #6A2D78, #4E2E6F); }
.fill-gold { background: linear-gradient(90deg, #F07935, #C02991); }

.radar-score-badge {
  font-size: 0.8rem;
  font-weight: 700;
  font-family: var(--font-display);
  color: var(--text-muted);
  min-width: 42px;
  text-align: right;
}


.teacher-letter-card {
  position: relative;
  background: var(--bg-card);
  border: 1.5px solid rgba(192, 41, 145, 0.25);
  border-radius: var(--radius-md);
  padding: 1.6rem;
  margin-top: 1.2rem;
  box-shadow: 0 4px 16px rgba(17, 43, 73, 0.05);
}

.teacher-letter-card::before {
  content: '“';
  position: absolute;
  top: -12px;
  left: 20px;
  font-size: 3.5rem;
  color: var(--c-hong-sen);
  opacity: 0.25;
  font-family: serif;
  line-height: 1;
}

.teacher-stamp {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 0.85rem;
  background: var(--c-nhan-nhe);
  border: 1px dashed var(--c-nhan);
  border-radius: var(--radius-sm);
  font-size: 0.76rem;
  font-weight: 700;
  color: var(--c-nhan);
  margin-top: 1rem;
}


.visual-lab-console {
  position: relative;
  background: var(--bg-card);
  border: 1.5px solid rgba(31, 87, 97, 0.35);
  border-radius: var(--radius-lg);
  padding: 2.2rem;
  box-shadow: var(--shadow-card);
}

.visual-lab-console::after {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 24px;
  height: 24px;
  background: linear-gradient(135deg, transparent 50%, var(--c-cam) 50%);
  border-top-right-radius: var(--radius-lg);
}

.lab-status-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.2rem;
  padding-bottom: 0.8rem;
  border-bottom: 1px solid var(--border-subtle);
  flex-wrap: wrap;
  gap: 0.6rem;
}

.lab-status-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.74rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  padding: 0.25rem 0.65rem;
  background: rgba(31, 87, 97, 0.12);
  color: var(--c-xanh-ok);
  border: 1px solid rgba(27, 110, 98, 0.3);
  border-radius: var(--radius-full);
  text-transform: uppercase;
}

.lab-status-chip::before {
  content: '';
  width: 6px;
  height: 6px;
  background: var(--c-xanh-ok);
  border-radius: 50%;
  box-shadow: 0 0 6px rgba(27, 110, 98, 0.6);
  animation: pulseGreen 2s infinite;
}

@media (max-width: 768px) {
  .circuit-stream {
    padding-left: 0;
  }
  .circuit-stream::before {
    display: none;
  }
  .circuit-stream-badge {
    position: static;
    margin-bottom: 0.8rem;
  }
  .student-radar-container {
    grid-template-columns: 1fr;
  }
}



@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 3rem;
  }
  .smart-steps-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .roadmap-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  .mobile-menu-btn {
    display: block;
  }
  .hero-title {
    font-size: 2.4rem;
  }
  .smart-steps-grid {
    grid-template-columns: 1fr;
  }
  .roadmap-grid {
    grid-template-columns: 1fr;
  }
  .hero-stats {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
  #cmate-widget-root {
    bottom: 16px;
    right: 16px;
  }
  .cmate-modal {
    right: 16px;
    bottom: 84px;
    width: calc(100vw - 32px);
  }
  .grid-stack {
    grid-template-columns: 1fr !important;
    gap: 1.5rem !important;
  }
  .nav-links.mo {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-card);
    padding: 1.5rem;
    border-bottom: 1px solid var(--border-subtle);
    box-shadow: var(--shadow-card);
  }
}


@media (max-width: 768px) {
  .hero-visual { overflow: hidden; }
}




.planner-controls {
  display: grid;
  grid-template-columns: 1.5fr 1.5fr 1fr;
  gap: 1.2rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.4rem;
  margin-bottom: 2rem;
  position: relative;
}

.planner-controls::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--gradient-logo);
  border-top-left-radius: var(--radius-md);
  border-bottom-left-radius: var(--radius-md);
}

.planner-select {
  width: 100%;
  padding: 0.65rem 1rem;
  border-radius: var(--radius-sm);
  border: 1.5px solid var(--border-subtle);
  background: var(--bg-card);
  color: var(--text-main);
  font-family: inherit;
  font-size: 0.92rem;
  transition: all var(--transition-fast);
  cursor: pointer;
}

.planner-select:focus {
  outline: none;
  border-color: var(--c-hong-sen);
  box-shadow: 0 0 0 3px var(--c-hong-sen-glow);
}

.planner-timeline {
  display: flex;
  flex-direction: column;
  gap: 1.2rem;
  position: relative;
}

.planner-week-card {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-card);
  border: 1.5px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.2rem 1.6rem;
  transition: all var(--transition-smooth);
  flex-wrap: wrap;
  gap: 1rem;
  overflow: hidden;
}

.planner-week-card::before {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 14px;
  height: 14px;
  background: linear-gradient(135deg, transparent 50%, var(--c-cam) 50%);
  opacity: 0.85;
}

.planner-week-card:hover {
  transform: translateX(6px);
  border-color: rgba(192, 41, 145, 0.45);
  box-shadow: 0 6px 20px rgba(17, 43, 73, 0.08);
}

.planner-week-info {
  display: flex;
  align-items: center;
  gap: 1.4rem;
  flex: 1;
  min-width: 260px;
}

.planner-week-badge {
  background: var(--gradient-btn);
  color: #fff;
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 800;
  padding: 0.5rem 1rem;
  border-radius: var(--radius-sm);
  white-space: nowrap;
  box-shadow: 0 3px 10px rgba(192, 41, 145, 0.25);
}

.planner-topic-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.3rem;
}

.planner-topic-sub {
  font-size: 0.86rem;
  color: var(--text-muted);
  line-height: 1.5;
}



@media print {
  body { background: #fff; color: #000; font-size: 12pt; }
  .site-header, .site-footer, .ambient-bg, .cmate-widget-root,
  #cmate-widget-root, .skip-link, .mobile-menu-btn,
  .btn, .nav-actions { display: none !important; }
  main { padding: 0 !important; }
  .glass-card { box-shadow: none; border: 1px solid #ccc; page-break-inside: avoid; }
  a { color: #000; text-decoration: underline; }
  a[href^="http"]::after { content: " (" attr(href) ")"; font-size: 0.8em; color: #666; }
  img { max-width: 100% !important; }
  .scroll-reveal { opacity: 1 !important; transform: none !important; }
}


.planner-levels {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.planner-level-dot {
  font-size: 0.74rem;
  font-weight: 700;
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius-full);
  border: 1px solid transparent;
}

.level-m1 {
  background: rgba(27, 110, 98, 0.1);
  color: var(--c-xanh-ok);
  border-color: rgba(27, 110, 98, 0.3);
}

.level-m2 {
  background: rgba(17, 43, 73, 0.1);
  color: var(--c-navy);
  border-color: rgba(17, 43, 73, 0.3);
}

.level-m3 {
  background: var(--c-nhan-nhe);
  color: var(--c-nhan);
  border-color: rgba(123, 46, 134, 0.3);
}

.level-m4 {
  background: rgba(240, 121, 53, 0.12);
  color: var(--c-cam);
  border-color: rgba(240, 121, 53, 0.35);
}


.level-d1 {
  background: rgba(27, 110, 98, 0.10);
  color: var(--c-xanh-ok);
  border-color: rgba(27, 110, 98, 0.30);
}

.level-d2 {
  background: rgba(56, 189, 248, 0.10);
  color: #0284c7;
  border-color: rgba(2, 132, 199, 0.30);
}

.level-d3 {
  background: rgba(17, 43, 73, 0.10);
  color: var(--c-navy);
  border-color: rgba(17, 43, 73, 0.30);
}

.level-d4 {
  background: rgba(240, 121, 53, 0.12);
  color: var(--c-cam);
  border-color: rgba(240, 121, 53, 0.35);
}

.level-d5 {
  background: var(--c-nhan-nhe);
  color: var(--c-nhan);
  border-color: rgba(123, 46, 134, 0.30);
}

.level-d6 {
  background: rgba(192, 41, 145, 0.10);
  color: var(--c-hong-sen);
  border-color: rgba(192, 41, 145, 0.35);
}

@media (max-width: 768px) {
  .planner-controls {
    grid-template-columns: 1fr;
  }
  .planner-week-card {
    flex-direction: column;
    align-items: flex-start;
  }
}


.visual-canvas-area {
  background-image: 
    radial-gradient(circle, var(--border-subtle) 1.2px, transparent 1.2px),
    linear-gradient(to right, rgba(17, 43, 73, 0.02) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(17, 43, 73, 0.02) 1px, transparent 1px);
  background-size: 24px 24px, 120px 120px, 120px 120px;
}

[data-theme="dark"] .visual-canvas-area {
  background-image: 
    radial-gradient(circle, rgba(255, 255, 255, 0.12) 1.2px, transparent 1.2px),
    linear-gradient(to right, rgba(255, 255, 255, 0.03) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
}


.quick-preset-dock {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  margin-top: 0.8rem;
  flex-wrap: wrap;
}

.quick-preset-label {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-dim);
}

.quick-chip-btn {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  padding: 0.3rem 0.85rem;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--text-main);
  cursor: pointer;
  transition: all var(--transition-fast);
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.quick-chip-btn::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--c-cam);
}

.quick-chip-btn:hover {
  background: var(--c-nhan-nhe);
  border-color: var(--c-nhan);
  color: var(--c-nhan);
  transform: translateY(-2px);
}

.quick-chip-btn.active {
  background: var(--gradient-btn);
  color: #fff;
  border-color: transparent;
  box-shadow: 0 2px 8px rgba(192, 41, 145, 0.3);
}

.quick-chip-btn.active::before {
  background: #fff;
}



h1, h2, h3, h4, .section-title, .section-subtitle, .hero-title, .hero-subtitle, .planner-topic-title { text-wrap: balance; }
body, p { text-wrap: pretty; }
.legend-item { white-space: nowrap; }  


.nav-actions .btn { white-space: nowrap; }
@media (max-width: 520px) {
  .nav-actions .btn { display: none; }
}


#hero { overflow-x: hidden; overflow-x: clip; }



.testimonial-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  max-width: 1100px;
  margin: 0 auto;
}

.testimonial-card {
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1.2rem;
}

.testimonial-stars {
  color: var(--c-cam);
  font-size: 1.1rem;
  letter-spacing: 2px;
}

.testimonial-text {
  font-size: 0.92rem;
  line-height: 1.8;
  color: var(--text-main);
  font-style: italic;
  flex: 1;
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border-subtle);
}

.testimonial-avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 800;
  font-size: 0.82rem;
  font-family: var(--font-display);
  flex-shrink: 0;
}

.testimonial-name {
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--text-main);
}

.testimonial-role {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 500;
}

@media (max-width: 768px) {
  .testimonial-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}

@media (max-width: 1024px) and (min-width: 769px) {
  .testimonial-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .testimonial-grid > :last-child {
    grid-column: 1 / -1;
    max-width: 540px;
    margin: 0 auto;
  }
}




@media (max-width: 768px) {
  
  .cmate-trio-grid { grid-template-columns: 1fr !important; }
  
  .cmate-den-grid { grid-template-columns: repeat(2, 1fr) !important; }
}

@media (max-width: 480px) {
  .cmate-den-grid { grid-template-columns: 1fr !important; }
}



.logo-gradient-bar::after { left: 0; transform: translateX(-200%); animation: anhSangGPU 4s infinite linear; }
@keyframes anhSangGPU { from { transform: translateX(-100%); } to { transform: translateX(300%); } }

.cmate-progress-fill { transform-origin: left center; animation: demNguocGPU 5s linear forwards; }
@keyframes demNguocGPU { from { transform: scaleX(1); } to { transform: scaleX(0); } }

.cmate-badge-pulse { animation: none; }
.cmate-badge-pulse::after {
  content: ''; position: absolute; inset: -2px; border-radius: 50%;
  background: rgba(27, 110, 98, 0.55); animation: vongXanhGPU 2s infinite; pointer-events: none;
}
@keyframes vongXanhGPU { 0% { transform: scale(1); opacity: 0.7; } 70% { transform: scale(2.05); opacity: 0; } 100% { transform: scale(2.05); opacity: 0; } }

.lab-status-chip::before { animation: nhipChamGPU 2s infinite; }
@keyframes nhipChamGPU { 0%, 100% { transform: scale(1); opacity: 1; } 70% { transform: scale(1.6); opacity: 0.55; } }

.circuit-orange-pin { animation: nutCamGPU 2.5s infinite alternate; }
@keyframes nutCamGPU { from { transform: scale(0.9); } to { transform: scale(1.2); } }


@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important;
                           transition-duration: 0.01ms !important; scroll-behavior: auto !important; }
}




.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::marker { content: ''; }
.faq-item[open] .faq-chevron { transform: rotate(180deg); }
.faq-summary:hover { background: var(--bg-subtle) !important; }
.faq-summary:focus-visible { outline: 2px solid var(--c-nhan); outline-offset: 2px; }




.scroll-reveal {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}
.scroll-reveal.revealed {
  opacity: 1;
  transform: translateY(0);
}


.scroll-reveal:nth-child(2) { transition-delay: 0.1s; }
.scroll-reveal:nth-child(3) { transition-delay: 0.2s; }
.scroll-reveal:nth-child(4) { transition-delay: 0.3s; }
.scroll-reveal:nth-child(5) { transition-delay: 0.4s; }
.scroll-reveal:nth-child(6) { transition-delay: 0.5s; }


@media (prefers-reduced-motion: reduce) {
  .scroll-reveal { opacity: 1; transform: none; transition: none; }
}



.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  z-index: 9999;
  background: var(--gradient-btn);
  color: #fff;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-full);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.92rem;
  text-decoration: none;
  white-space: nowrap;
  transition: top 0.2s ease;
}
.skip-link:focus {
  top: 1rem;
  outline: 3px solid var(--c-cam);
  outline-offset: 2px;
}


.scratchpad-wrapper {
  margin-top: 1.2rem;
  margin-bottom: 1.5rem;
  background: var(--bg-secondary);
  border: 1.5px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: 0 4px 18px rgba(0, 0, 0, 0.04);
  transition: all 0.3s ease;
}
.scratchpad-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.6rem;
  padding: 0.6rem 1rem;
  background: var(--bg-card);
  border-bottom: 1px solid var(--border-subtle);
}
.scratchpad-tools-left {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  flex-wrap: wrap;
}
.scratchpad-tool-btn {
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-full);
  border: 1.5px solid var(--border-subtle);
  background: var(--bg-secondary);
  color: var(--text-main);
  font-size: 0.82rem;
  font-weight: 700;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  transition: all 0.15s ease;
}
.scratchpad-tool-btn:hover {
  border-color: var(--c-nhan);
  color: var(--c-nhan);
}
.scratchpad-tool-btn.active {
  background: var(--c-nhan-nhe);
  border-color: var(--c-nhan);
  color: var(--c-nhan);
}
.scratchpad-color-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  display: inline-block;
}
.scratchpad-canvas {
  display: block;
  width: 100%;
  height: 240px;
  background-color: var(--bg-secondary);
  background-image: radial-gradient(var(--border-subtle) 1px, transparent 1px);
  background-size: 20px 20px;
  cursor: crosshair;
  touch-action: none;
}


.converter-card {
  background: var(--bg-card);
  border: 1.5px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 2rem;
  position: relative;
  overflow: hidden;
}
.converter-chip {
  padding: 0.4rem 0.85rem;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-subtle);
  background: var(--bg-secondary);
  font-size: 0.84rem;
  font-weight: 600;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s ease;
}
.converter-chip:hover {
  background: var(--c-nhan-nhe);
  color: var(--c-nhan);
  border-color: var(--c-nhan);
  transform: translateY(-1px);
}
.converter-output-box {
  border-radius: var(--radius-md);
  padding: 1.4rem;
  margin-top: 1.2rem;
  transition: all 0.25s ease;
}


.worksheet-modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(10, 14, 28, 0.75);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 10000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
}
.worksheet-modal-card {
  background: var(--bg-card);
  color: var(--text-main);
  max-width: 820px;
  width: 100%;
  max-height: 90vh;
  border-radius: var(--radius-md);
  border: 1.5px solid var(--border-subtle);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  box-shadow: 0 20px 48px rgba(0, 0, 0, 0.25);
  animation: modalScaleIn 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}
@keyframes modalScaleIn {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}
.worksheet-header {
  padding: 1.2rem 1.5rem;
  border-bottom: 2px solid var(--c-nhan);
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--bg-secondary);
}
.worksheet-body {
  padding: 1.8rem;
  overflow-y: auto;
  line-height: 1.7;
}
.worksheet-section-title {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.95rem;
  font-weight: 800;
  color: var(--c-nhan);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.6rem;
  margin-top: 1rem;
}
.worksheet-box {
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  padding: 1rem 1.2rem;
  background: var(--bg-secondary);
  margin-bottom: 0.8rem;
}


.quiz-dot {
  display: inline-block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--border-subtle);
  cursor: pointer;
  transition: all var(--transition-fast);
  border: 1.5px solid transparent;
}
.quiz-dot:hover {
  background: var(--c-nhan-nhe);
  border-color: var(--c-nhan);
  transform: scale(1.3);
}
.quiz-dot.active {
  background: var(--c-nhan);
  border-color: var(--c-nhan);
  transform: scale(1.3);
}
.quiz-dot.done {
  background: var(--c-xanh-ok);
  border-color: var(--c-xanh-ok);
}


.quiz-progress-bar {
  width: 100%;
  height: 6px;
  background: var(--border-subtle);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-top: 0.5rem;
}
.quiz-progress-fill {
  height: 100%;
  background: var(--gradient-btn);
  border-radius: var(--radius-full);
  transition: width 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
  min-width: 0;
}
.quiz-progress-text {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--text-muted);
  text-align: center;
  margin-top: 0.25rem;
}


@keyframes bounceIn {
  0% { transform: scale(0.95); opacity: 0.7; }
  50% { transform: scale(1.02); }
  100% { transform: scale(1); opacity: 1; }
}
@keyframes shakeX {
  0%, 100% { transform: translateX(0); }
  15%, 45%, 75% { transform: translateX(-6px); }
  30%, 60%, 90% { transform: translateX(6px); }
}
.anim-bounce-in {
  animation: bounceIn 0.45s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.anim-shake {
  animation: shakeX 0.5s ease-in-out;
}
@media (prefers-reduced-motion: reduce) {
  .anim-bounce-in, .anim-shake { animation: none; }
}