/* Base - Brand Color System (#9c0041, #043584) */
* { box-sizing: border-box; }
:root { 
  /* Primary Brand Colors from logo */
  --brand-red:#9c0041;           /* Logo red */
  --brand-blue:#043584;          /* Logo blue */
  --brand-red-light:#fde7f1;     /* Tint of logo red */
  --brand-blue-light:#e9f0ff;    /* Tint of logo blue */
  
  /* Secondary tints (approximate) */
  --brand-red-100:#fbd1e3;
  --brand-blue-100:#d6e3ff;
  --brand-red-200:#f7a9c9;
  --brand-blue-200:#b7ccff;
  --brand-red-300:#f381b0;
  --brand-blue-300:#99b5ff;
  --brand-red-400:#e65b97;
  --brand-blue-400:#6f92f5;
  --brand-red-500:#c83a78;
  --brand-blue-500:#4f73e6;
  
  /* Accent Colors */
  --accent-orange:#f97316;       /* Orange accent */
  --accent-green:#059669;        /* Green accent */
  --accent-purple:#7c3aed;       /* Purple accent */
  
  /* Text Colors */
  --text-dark:#1f2937;           /* Dark text */
  --text-muted:#6b7280;          /* Muted text */
  --text-light:#9ca3af;          /* Light text */
}
html, body { height: 100%; }
body {
  margin: 0;
  font-family: 'Inter', system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, 'Apple Color Emoji', 'Segoe UI Emoji';
  color: var(--text-dark);
  background: #ffffff;
  line-height: 1.6;
}

.container {
  width: 100%;
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 20px;
}

.sr-only { position: absolute; width: 1px; height: 1px; margin: -1px; padding: 0; border: 0; clip: rect(0 0 0 0); overflow: hidden; }

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,0.8);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid #e2e8f0;
}
.header-inner { display: flex; align-items: center; justify-content: space-between; padding: 14px 0; }
.logo { display: inline-flex; align-items: center; gap: 10px; color: inherit; text-decoration: none; font-weight: 700; }
.logo-mark { width: 28px; height: 28px; border-radius: 8px; background: linear-gradient(135deg, var(--brand-crimson), var(--brand-blue)); display: inline-block; }
.logo-text { letter-spacing: 0.2px; }

.nav-toggle { display: none; background: transparent; border: none; font-size: 22px; }
.nav-menu { list-style: none; display: flex; gap: 16px; margin: 0; padding: 0; align-items: center; }
.nav-menu a { color: #0f172a; text-decoration: none; padding: 8px 10px; border-radius: 8px; }
.nav-menu a:hover { background: #f1f5f9; }

/* Buttons - Enhanced with stronger visual impact */
.btn { 
  display: inline-flex; 
  align-items: center; 
  justify-content: center; 
  gap: 8px; 
  padding: 12px 16px; 
  border-radius: 10px; 
  text-decoration: none; 
  border: 1px solid transparent; 
  font-weight: 600; 
  cursor: pointer;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}
.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
  transition: left 0.5s;
}
.btn:hover::before {
  left: 100%;
}
.btn-sm { padding: 8px 12px; font-size: 14px; }
.btn-primary { 
  background: linear-gradient(135deg, var(--brand-blue), #1d4ed8); 
  color: #fff; 
  border-color: var(--brand-blue);
  box-shadow: 0 4px 15px rgba(30, 64, 175, 0.3);
}
.btn-primary:hover { 
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(30, 64, 175, 0.4);
}
.btn-secondary { 
  background: linear-gradient(135deg, var(--brand-red), #b91c1c); 
  color: #fff; 
  border-color: var(--brand-red);
  box-shadow: 0 4px 15px rgba(220, 38, 38, 0.3);
}
.btn-secondary:hover { 
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(220, 38, 38, 0.4);
}
.btn-outline { 
  background: transparent; 
  color: var(--text-dark); 
  border-color: var(--brand-blue);
  border-width: 2px;
}
.btn-outline:hover { 
  background: var(--brand-blue); 
  color: #fff;
  transform: translateY(-2px);
}

/* Hero - Enhanced with dynamic visual impact */
.hero { 
  position: relative; 
  padding: 72px 0; 
  background: #ffffff;
  overflow: hidden;
  border-bottom: 1px solid #e5e7eb;
}
.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: 
    linear-gradient(135deg, var(--brand-blue-light) 0%, transparent 60%),
    linear-gradient(225deg, var(--brand-red-light) 0%, transparent 60%);
  opacity: 0.3;
  pointer-events: none;
}
@keyframes float {
  0%, 100% { transform: translate(0, 0) rotate(0deg); }
  33% { transform: translate(30px, -30px) rotate(120deg); }
  66% { transform: translate(-20px, 20px) rotate(240deg); }
}
.hero-inner { 
  display: grid; 
  grid-template-columns: 1.2fr 1fr; 
  gap: 32px; 
  align-items: center;
  position: relative;
  z-index: 2;
}
.hero h1 { 
  font-size: 40px; 
  line-height: 1.15; 
  margin: 0 0 14px; 
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, var(--text-dark), var(--brand-blue));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero p { 
  font-size: 18px; 
  color: var(--text-muted); 
  margin: 0 0 18px; 
}
.hero-actions { 
  display: flex; 
  gap: 12px; 
  margin: 14px 0 8px; 
  flex-wrap: wrap; 
}
.hero-highlights { 
  display: flex; 
  gap: 16px; 
  flex-wrap: wrap; 
  list-style: none; 
  margin: 18px 0 0; 
  padding: 0; 
  color: var(--text-dark); 
}
.hero-highlights li { 
  background: linear-gradient(135deg, #fff, #f8fafc); 
  border: 1px solid #e2e8f0; 
  padding: 8px 12px; 
  border-radius: 999px; 
  font-size: 14px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  transition: all 0.3s ease;
}
.hero-highlights li:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}
.hero-media { 
  display: grid; 
  place-items: center; 
}
.hero-image { 
  width: 100%; 
  max-width: 520px; 
  border-radius: 16px; 
  box-shadow: 0 20px 40px rgba(2,6,23,.15); 
  border: 1px solid #e2e8f0;
  transition: all 0.3s ease;
}
.hero-image:hover {
  transform: translateY(-5px);
  box-shadow: 0 25px 50px rgba(2,6,23,.2);
}

/* Sections */
.section { padding: 64px 0; }
.section-head { max-width: 900px; margin: 0 auto 28px; text-align: center; }
.section-head h2 { font-size: 28px; margin: 0 0 8px; letter-spacing: -0.01em; font-weight: 700; color: inherit; font-family: inherit; }
.section-head p { color: #475569; margin: 0; max-width: 820px; margin-left: auto; margin-right: auto; text-align: center; }

/* ===========================================
   SCROLL ANIMATIONS & VISUAL EFFECTS
   =========================================== */

/* Base animation classes */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

.slide-in-left {
  opacity: 0;
  transform: translateX(-50px);
  transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.slide-in-left.visible {
  opacity: 1;
  transform: translateX(0);
}

.slide-in-right {
  opacity: 0;
  transform: translateX(50px);
  transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.slide-in-right.visible {
  opacity: 1;
  transform: translateX(0);
}

.scale-in {
  opacity: 0;
  transform: scale(0.8);
  transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.scale-in.visible {
  opacity: 1;
  transform: scale(1);
}

/* Staggered animations for cards */
.stagger-item {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.stagger-item.visible {
  opacity: 1;
  transform: translateY(0);
}

.stagger-item:nth-child(1) { transition-delay: 0.1s; }
.stagger-item:nth-child(2) { transition-delay: 0.2s; }
.stagger-item:nth-child(3) { transition-delay: 0.3s; }
.stagger-item:nth-child(4) { transition-delay: 0.4s; }
.stagger-item:nth-child(5) { transition-delay: 0.5s; }
.stagger-item:nth-child(6) { transition-delay: 0.6s; }
.stagger-item:nth-child(7) { transition-delay: 0.7s; }
.stagger-item:nth-child(8) { transition-delay: 0.8s; }

/* ===========================================
   SECTION BACKGROUND SYSTEM - HARMONIOUS COLOR SCHEME
   =========================================== */

/* Base section styling */
.section { 
  position: relative; 
  background: #ffffff;
  /* Removed border-top to eliminate horizontal lines between sections */
}

/* Ensure all section content is above backgrounds */
.section > .container { 
  position: relative; 
  z-index: 1; 
}

/* ===========================================
   SPECIFIC SECTION BACKGROUNDS
   =========================================== */

/* 1. HERO BANNER - Enhanced with animations */
.hero-banner {
  background: transparent;
  margin: 0;
  padding: 0;
  line-height: 0;
  position: relative;
  overflow: hidden;
}

.hero-banner picture, 
.hero-banner img {
  max-width: 100%;
  transition: transform 0.3s ease;
}

.hero-banner:hover img {
  transform: scale(1.02);
}

/* Animated overlay for hero banner */
.hero-banner::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(
    45deg,
    rgba(4,53,132,0.1) 0%,
    transparent 30%,
    transparent 70%,
    rgba(156,0,65,0.1) 100%
  );
  animation: heroShimmer 8s ease-in-out infinite;
  pointer-events: none;
  z-index: 1;
}

@keyframes heroShimmer {
  0%, 100% { 
    opacity: 0.3;
    transform: translateX(-100%);
  }
  50% { 
    opacity: 0.6;
    transform: translateX(100%);
  }
}

/* 2. BENEFITS SECTION - "Tại sao chọn chúng tôi?" */
#loi-ich { 
  position: relative; 
  background: transparent; 
  overflow: hidden;
  /* Removed border-top */
}
#loi-ich::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50vw; 
  transform: translateX(-50vw);
  width: 100vw; /* Full viewport width to match banner */
  background: linear-gradient(135deg, 
    var(--brand-blue-light) 0%, 
    rgba(255,255,255,0.8) 50%, 
    var(--brand-red-light) 100%);
  opacity: 0.4;
  pointer-events: none; 
  z-index: 0;
}

/* Floating particles effect for benefits section */
#loi-ich::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    radial-gradient(circle at 20% 20%, rgba(4,53,132,0.1) 2px, transparent 2px),
    radial-gradient(circle at 80% 80%, rgba(156,0,65,0.1) 2px, transparent 2px),
    radial-gradient(circle at 40% 60%, rgba(4,53,132,0.05) 1px, transparent 1px);
  background-size: 100px 100px, 150px 150px, 200px 200px;
  animation: floatParticles 20s ease-in-out infinite;
  pointer-events: none;
  z-index: 0;
}

@keyframes floatParticles {
  0%, 100% { transform: translateY(0px) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(180deg); }
}

/* 3. ONLINE SECTION - "Loại Hình Đào Tạo" */
#online { 
  position: relative; 
  background: transparent; 
  overflow: hidden;
  /* Removed border-top */
}
#online::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50vw; 
  transform: translateX(-50vw);
  width: 100vw; /* Full viewport width to match banner */
  background: linear-gradient(45deg, 
    var(--brand-red-light) 0%, 
    rgba(255,255,255,0.9) 50%, 
    var(--brand-blue-light) 100%);
  opacity: 0.3;
  pointer-events: none; 
  z-index: 0;
}

/* Animated geometric shapes for online section */
#online::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    radial-gradient(circle at 20% 20%, rgba(4,53,132,0.08) 4px, transparent 4px),
    radial-gradient(circle at 80% 80%, rgba(156,0,65,0.08) 4px, transparent 4px),
    radial-gradient(circle at 50% 50%, rgba(4,53,132,0.05) 2px, transparent 2px);
  background-size: 120px 120px, 180px 180px, 240px 240px;
  animation: gentleFloat 25s ease-in-out infinite;
  pointer-events: none;
  z-index: 0;
}

@keyframes gentleFloat {
  0%, 100% { 
    transform: translateY(0px) rotate(0deg);
    opacity: 0.3;
  }
  33% { 
    transform: translateY(-15px) rotate(120deg);
    opacity: 0.6;
  }
  66% { 
    transform: translateY(-8px) rotate(240deg);
    opacity: 0.4;
  }
}

/* 4. COURSES SECTION - "Danh sách ngành học" */
#khoa-hoc { 
  position: relative; 
  background: transparent; 
  overflow: hidden;
  /* Removed border-top */
}
#khoa-hoc::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50vw; 
  transform: translateX(-50vw);
  width: 100vw; /* Full viewport width to match banner */
  background: linear-gradient(180deg, 
    rgba(255,255,255,0.95) 0%, 
    var(--brand-blue-light) 30%, 
    rgba(255,255,255,0.9) 70%, 
    var(--brand-red-light) 100%);
  opacity: 0.2;
  pointer-events: none; 
  z-index: 0;
}

/* Pulsing dots effect for courses section */
#khoa-hoc::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    radial-gradient(circle at 25% 25%, rgba(4,53,132,0.15) 3px, transparent 3px),
    radial-gradient(circle at 75% 75%, rgba(156,0,65,0.15) 3px, transparent 3px),
    radial-gradient(circle at 50% 50%, rgba(4,53,132,0.08) 2px, transparent 2px);
  background-size: 80px 80px, 120px 120px, 160px 160px;
  animation: pulseDots 12s ease-in-out infinite;
  pointer-events: none;
  z-index: 0;
}

@keyframes pulseDots {
  0%, 100% { 
    opacity: 0.3;
    transform: scale(1);
  }
  50% { 
    opacity: 0.8;
    transform: scale(1.1);
  }
}

/* ===========================================
   INTERACTIVE HOVER EFFECTS
   =========================================== */

/* Enhanced card hover effects */
.benefit-item, .benefit-card, .course-card, article {
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.benefit-item:hover, .benefit-card:hover, .course-card:hover, article:hover {
  transform: translateY(-8px) scale(1.02);
  box-shadow: 
    0 20px 40px rgba(0,0,0,0.1),
    0 0 0 1px rgba(4,53,132,0.1);
}

.benefit-item::before, .benefit-card::before, .course-card::before, article::before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(255,255,255,0.4),
    transparent
  );
  transition: left 0.6s ease;
}

.benefit-item:hover::before, .benefit-card:hover::before, .course-card:hover::before, article:hover::before {
  left: 100%;
}

/* Button enhancements */
.btn, .bkeuni-actions button {
  position: relative;
  overflow: hidden;
  transition: all 0.3s ease;
}

.btn::before, .bkeuni-actions button::before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(255,255,255,0.2),
    transparent
  );
  transition: left 0.5s ease;
}

.btn:hover::before, .bkeuni-actions button:hover::before {
  left: 100%;
}

.btn:hover, .bkeuni-actions button:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

/* Form field focus effects */
.bkeuni-field input:focus, .bkeuni-field select:focus {
  transform: scale(1.02);
  box-shadow: 
    0 0 0 3px rgba(4,53,132,0.1),
    0 4px 12px rgba(0,0,0,0.1);
  border-color: var(--brand-blue);
}

/* ===========================================
   CHECK MARKS & ICONS STYLING - GREEN COLOR
   =========================================== */

/* Force all check marks to be green */
li::marker,
.checkmark,
.check-mark,
.check-icon,
.fa-check,
.fa-check-circle,
.icon-check,
[class*="check"],
[class*="tick"] {
  color: var(--accent-green) !important;
}

/* Specific targeting for common check mark patterns */
ul li::before,
ol li::before,
.benefit-item li::before,
.course-item li::before,
.feature-item li::before,
.online-item li::before {
  color: var(--accent-green) !important;
}

/* SVG check marks */
svg[class*="check"],
svg[class*="tick"],
.checkmark svg,
.check-icon svg {
  fill: var(--accent-green) !important;
  color: var(--accent-green) !important;
}

/* Unicode check marks */
li::marker {
  color: var(--accent-green) !important;
}

/* Custom check mark styling */
.check-green {
  color: var(--accent-green) !important;
}

/* Specific check marks in sections */
#online ul li::before,
#online ol li::before,
#online li::marker,
#online .checkmark,
#online .check-icon {
  color: var(--accent-green) !important;
}

#loi-ich ul li::before,
#loi-ich ol li::before,
#loi-ich li::marker,
#loi-ich .checkmark,
#loi-ich .check-icon {
  color: var(--accent-green) !important;
}

#khoa-hoc ul li::before,
#khoa-hoc ol li::before,
#khoa-hoc li::marker,
#khoa-hoc .checkmark,
#khoa-hoc .check-icon {
  color: var(--accent-green) !important;
}

/* Override any existing check mark colors */
*[class*="check"] {
  color: var(--accent-green) !important;
}

*[class*="tick"] {
  color: var(--accent-green) !important;
}

/* FontAwesome check icons */
.fa-check,
.fa-check-circle,
.fa-check-square {
  color: var(--accent-green) !important;
}

/* Target specific check marks in course cards */
.course-card li::before,
.course-card li::marker,
article li::before,
article li::marker {
  color: var(--accent-green) !important;
}

/* Force all check marks in the entire page */
body li::before,
body li::marker,
body .checkmark,
body .check-icon {
  color: var(--accent-green) !important;
}

/* SUPER SPECIFIC targeting for course cards check marks */
#khoa-hoc .course-card ul li::before,
#khoa-hoc .course-card ol li::before,
#khoa-hoc .course-card li::before,
#khoa-hoc article ul li::before,
#khoa-hoc article ol li::before,
#khoa-hoc article li::before,
#khoa-hoc .course-item ul li::before,
#khoa-hoc .course-item ol li::before,
#khoa-hoc .course-item li::before {
  color: #059669 !important;
  /* Remove content to avoid duplicate checkmarks */
}

#khoa-hoc .course-card ul li::marker,
#khoa-hoc .course-card ol li::marker,
#khoa-hoc .course-card li::marker,
#khoa-hoc article ul li::marker,
#khoa-hoc article ol li::marker,
#khoa-hoc article li::marker,
#khoa-hoc .course-item ul li::marker,
#khoa-hoc .course-item ol li::marker,
#khoa-hoc .course-item li::marker {
  color: #059669 !important;
}

/* Target any element containing check marks in course section */
#khoa-hoc *[class*="check"],
#khoa-hoc *[class*="tick"],
#khoa-hoc .checkmark,
#khoa-hoc .check-icon,
#khoa-hoc .fa-check,
#khoa-hoc .fa-check-circle {
  color: #059669 !important;
}

/* Nuclear option - target everything in course section */
#khoa-hoc li {
  color: inherit !important;
}

#khoa-hoc li::before {
  color: #059669 !important;
  /* Remove content to avoid duplicate */
}

#khoa-hoc li::marker {
  color: #059669 !important;
}

/* 5. FAQ SECTION - "Câu hỏi thường gặp" */
#faq { 
  position: relative; 
  background: transparent; 
  /* Removed border-top */
}
#faq::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50vw; 
  transform: translateX(-50vw);
  width: 100vw; /* Full viewport width to match banner */
  background: linear-gradient(90deg, 
    #f8fafc 0%, 
    rgba(255,255,255,0.8) 50%, 
    #f0f9ff 100%);
  opacity: 0.6;
  pointer-events: none; 
  z-index: 0;
}

/* Force uniform background for form section - override any conflicting styles */
section.bkeuni-form-section,
.section.bkeuni-form-section {
  background: transparent !important;
  background-color: transparent !important;
  background-image: none !important;
}

section.bkeuni-form-section::before,
.section.bkeuni-form-section::before {
  content: "" !important;
  position: absolute !important; 
  top: 0 !important; 
  bottom: 0 !important;
  left: 50vw !important; 
  transform: translateX(-50vw) !important;
  width: 100vw !important;
  background: linear-gradient(135deg, 
    var(--brand-blue-light) 0%, 
    rgba(255,255,255,0.9) 50%, 
    var(--brand-red-light) 100%) !important;
  opacity: 0.3 !important;
  pointer-events: none !important; 
  z-index: 0 !important;
}

/* ===========================================
   LEGACY THEME CLASSES (for compatibility)
   =========================================== */

.section.theme-soft-blue { 
  position: relative; 
  background: #ffffff;
  /* Removed border-top */
}
.section.theme-soft-blue::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50vw; 
  transform: translateX(-50vw);
  width: 100vw; /* Full viewport width to match banner */
  background: linear-gradient(135deg, var(--brand-blue-light) 0%, transparent 60%);
  opacity: 0.3;
  pointer-events: none; 
  z-index: 0;
}

.section.theme-dots { 
  position: relative; 
  background: linear-gradient(180deg, var(--brand-blue-light), #ffffff);
  /* Removed border-top */
}
.section.theme-dots::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50vw; 
  transform: translateX(-50vw);
  width: 100vw; /* Full viewport width to match banner */
  background: 
    linear-gradient(90deg, rgba(4,53,132,.08) 0%, transparent 50%),
    linear-gradient(180deg, rgba(156,0,65,.06), transparent 70%);
  opacity: .6;
  pointer-events: none; 
  z-index: 0;
}

.section.theme-light-blue { 
  position: relative; 
  background: transparent; 
}
.section.theme-light-blue::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50vw; 
  transform: translateX(-50vw);
  width: 100vw; /* Full viewport width to match banner */
  background: linear-gradient(180deg, #eef6ff, #ffffff);
  opacity: 0.9;
  pointer-events: none; 
  z-index: 0;
}
.section.theme-light-blue > .container { 
  position: relative; 
  z-index: 1; 
}

.section.theme-stripes { 
  position: relative; 
  background: #ffffff;
  border-top: 1px solid #e5e7eb;
}
.section.theme-stripes::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50%; 
  transform: translateX(-50%);
  width: 100vw;
  background: 
    linear-gradient(45deg, var(--brand-blue-light) 0%, transparent 40%),
    linear-gradient(225deg, var(--brand-red-light) 0%, transparent 40%);
  opacity: 0.15;
  pointer-events: none; 
  z-index: 0;
}

.section.theme-grid { 
  position: relative; 
  background: #ffffff;
  border-top: 1px solid #e5e7eb;
}
.section.theme-grid::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50%; 
  transform: translateX(-50%);
  width: 100vw;
  background: 
    radial-gradient(circle at 30% 30%, var(--brand-blue-light) 0%, transparent 50%),
    radial-gradient(circle at 70% 70%, var(--brand-red-light) 0%, transparent 50%);
  opacity: 0.1;
  pointer-events: none; 
  z-index: 0;
}

/* Viet My Style - Color Block Themes */
.section.theme-minimal { 
  position: relative; 
  background: #ffffff;
  border-left: 4px solid var(--brand-blue);
  border-top: 1px solid #e5e7eb;
}
.section.theme-minimal::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 0;
  width: 4px;
  background: linear-gradient(180deg, var(--brand-blue) 0%, var(--brand-red) 100%);
  pointer-events: none; 
  z-index: 0;
}

.section.theme-gradient { 
  position: relative; 
  background: #ffffff;
  border-top: 1px solid #e5e7eb;
}
.section.theme-gradient::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50%; 
  transform: translateX(-50%);
  width: 100vw;
  background: 
    linear-gradient(45deg, var(--brand-blue-light) 0%, transparent 50%),
    linear-gradient(135deg, transparent 0%, var(--brand-red-light) 100%);
  opacity: 0.2;
  pointer-events: none; 
  z-index: 0;
}

.section.theme-accent { 
  position: relative; 
  background: #ffffff;
  border-top: 1px solid #e5e7eb;
}
.section.theme-accent::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50%; 
  transform: translateX(-50%);
  width: 100vw;
  background: 
    linear-gradient(90deg, transparent 0%, var(--brand-red-light) 20%, transparent 40%, transparent 60%, var(--brand-blue-light) 80%, transparent 100%);
  opacity: 0.15;
  pointer-events: none; 
  z-index: 0;
}

/* Viet My Style - Special Color Block Themes */
.section.theme-red-block { 
  position: relative; 
  background: var(--brand-red);
  color: #ffffff;
}
.section.theme-red-block .section-head h2,
.section.theme-red-block .section-head p {
  color: #ffffff;
}
.section.theme-red-block::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50%; 
  transform: translateX(-50%);
  width: 100vw;
  background: 
    linear-gradient(135deg, rgba(255,255,255,0.1) 0%, transparent 50%);
  pointer-events: none; 
  z-index: 0;
}

.section.theme-blue-block { 
  position: relative; 
  background: var(--brand-blue);
  color: #ffffff;
}
.section.theme-blue-block .section-head h2,
.section.theme-blue-block .section-head p {
  color: #ffffff;
}
.section.theme-blue-block::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50%; 
  transform: translateX(-50%);
  width: 100vw;
  background: 
    linear-gradient(135deg, rgba(255,255,255,0.1) 0%, transparent 50%);
  pointer-events: none; 
  z-index: 0;
}

.section.theme-light-red { 
  position: relative; 
  background: var(--brand-red-light);
  border-top: 1px solid var(--brand-red-200);
}
.section.theme-light-red::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50%; 
  transform: translateX(-50%);
  width: 100vw;
  background: 
    linear-gradient(90deg, var(--brand-red-200) 0%, transparent 50%);
  opacity: 0.3;
  pointer-events: none; 
  z-index: 0;
}

.section.theme-light-blue { 
  position: relative; 
  background: var(--brand-blue-light);
  border-top: 1px solid var(--brand-blue-200);
}
.section.theme-light-blue::before {
  content: "";
  position: absolute; 
  top: 0; 
  bottom: 0;
  left: 50%; 
  transform: translateX(-50%);
  width: 100vw;
  background: 
    linear-gradient(90deg, var(--brand-blue-200) 0%, transparent 50%);
  opacity: 0.3;
  pointer-events: none; 
  z-index: 0;
}

/* Filters */
.filters { display: flex; gap: 12px; align-items: end; flex-wrap: wrap; background: #f8fafc; border: 1px solid #e2e8f0; padding: 12px; border-radius: 12px; margin-bottom: 18px; }
.filter-group { display: grid; gap: 6px; }
.filter-group label { font-size: 12px; color: #64748b; }
.filters select, .filters input[type="search"] { padding: 10px 12px; border-radius: 10px; border: 1px solid #cbd5e1; background: #fff; min-width: 180px; }
.search-group { flex: 1; min-width: 220px; }
.search-group input { width: 100%; }

/* Course grid - Enhanced with dynamic visual impact */
.course-grid { 
  display: grid; 
  grid-template-columns: repeat(3, 1fr); 
  gap: 18px; 
}
.course-card { 
  border: 1px solid #e2e8f0; 
  border-radius: 14px; 
  padding: 16px; 
  background: linear-gradient(135deg, #fff, #f8fafc); 
  display: grid; 
  gap: 10px; 
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}
.course-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--brand-blue), var(--brand-red));
  transform: scaleX(0);
  transition: transform 0.3s ease;
}
.course-card:hover::before {
  transform: scaleX(1);
}
.card-media { 
  position: relative; 
  width: 100%; 
  height: 240px; 
  border-radius: 12px; 
  background-size: cover; 
  background-position: center; 
  border: 1px solid #e2e8f0; 
  overflow: hidden;
  transition: all 0.3s ease;
}
.card-media::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, rgba(30, 64, 175, 0.1), rgba(220, 38, 38, 0.1));
  opacity: 0;
  transition: opacity 0.3s ease;
}
.course-card:hover .card-media::after {
  opacity: 1;
}
.card-pill { 
  position: absolute; 
  top: 10px; 
  right: 10px; 
  background: linear-gradient(135deg, var(--brand-blue), #1d4ed8); 
  color: #fff; 
  font-size: 12px; 
  font-weight: 700; 
  padding: 6px 10px; 
  border-radius: 999px; 
  box-shadow: 0 6px 14px rgba(30, 64, 175, 0.25);
  z-index: 2;
}
.course-card:hover { 
  transform: translateY(-8px); 
  box-shadow: 0 20px 40px rgba(2,6,23,.15);
}
.course-card h3 { 
  margin: 0; 
  font-size: 18px;
  color: var(--text-dark);
  transition: color 0.3s ease;
}
.course-card:hover h3 {
  color: var(--brand-blue);
}
.course-card p { 
  margin: 0; 
  color: var(--text-muted); 
}
.card-badge { 
  display: inline-block; 
  font-size: 12px; 
  padding: 6px 10px; 
  background: linear-gradient(135deg, #e8eefc, #dbeafe); 
  color: var(--brand-blue); 
  border-radius: 999px; 
  border: 1px solid #d7e3fb; 
}
.badge-b { 
  background: linear-gradient(135deg, #dbeafe, #bfdbfe); 
  color: #1e40af; 
  border-color: #bfdbfe; 
}
.card-meta { 
  list-style: none; 
  display: flex; 
  gap: 14px; 
  margin: 0; 
  padding: 0; 
  color: var(--text-muted); 
  font-size: 14px; 
}
.meta-list { 
  list-style: none; 
  margin: 6px 0 0; 
  padding: 0; 
  display: grid; 
  gap: 8px; 
  color: var(--text-dark); 
}
.meta-list li { 
  display: grid; 
  grid-template-columns: 18px 1fr; 
  align-items: start; 
  gap: 8px; 
  font-size: 14px; 
}
.meta-list .icon { 
  width: 18px; 
  height: 18px; 
  border-radius: 999px; 
  display: inline-grid; 
  place-items: center; 
  background: linear-gradient(135deg, #f0e4ea, #fce7f3); 
  color: var(--brand-crimson); 
  font-size: 12px; 
}
.card-actions { 
  margin-top: 4px; 
}

/* Benefits - Enhanced with dynamic visual impact */
.benefit-grid { 
  display: grid; 
  grid-template-columns: repeat(4, 1fr); 
  gap: 18px; 
}
.benefit-item { 
  background: linear-gradient(135deg, #ffffff, #f8fafc); 
  border: 1px solid #e2e8f0; 
  border-radius: 16px; 
  padding: 20px; 
  display: grid; 
  gap: 8px;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
  box-shadow: 0 10px 28px rgba(2,6,23,.06);
}
.benefit-item::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--brand-red), var(--brand-blue));
  transform: scaleX(0);
  transition: transform 0.3s ease;
}
.benefit-item:hover::before {
  transform: scaleX(1);
}
.benefit-item:hover {
  transform: translateY(-5px);
  box-shadow: 0 15px 30px rgba(0,0,0,0.1);
  border-color: var(--brand-blue);
}
.benefit-icon { 
  font-size: 24px;
  transition: all 0.3s ease;
}
.benefit-item:hover .benefit-icon {
  transform: scale(1.1);
}

/* Online section */
.section-online { background: linear-gradient(180deg, #ffffff, #f8fafc); }
.online-inner { display: grid; grid-template-columns: 1.1fr 1fr; gap: 18px; align-items: center; }
.online-copy h2 { font-size: 32px; margin: 0 0 10px; color: var(--brand-blue); }
.online-copy h2 span { color: var(--brand-red); }
.online-list { list-style: none; padding: 0; margin: 0 0 16px; display: grid; gap: 10px; color: #334155; }
.online-list li { position: relative; padding-left: 22px; }
.online-list li::before { content: "✔"; position: absolute; left: 0; top: 0; color: #ef4444; }
.online-stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-top: 8px; }
.stat { background: #fff; border: 1px solid #e2e8f0; border-radius: 14px; padding: 16px; text-align: center; }
.stat-number { font-size: 36px; font-weight: 800; letter-spacing: -0.02em; }
.stat-label { color: #64748b; }
.online-media { display: grid; place-items: center; }
/* Replace heavy black frame with elegant picture card */
.phone-mock { 
  width: 100%; max-width: 520px; border-radius: 18px; overflow: hidden; 
  background: #fff; position: relative; 
  box-shadow: 0 14px 34px rgba(2,6,23,.12), 0 4px 10px rgba(2,6,23,.06);
  border: 2px solid transparent;
  background-image: linear-gradient(#fff,#fff), linear-gradient(135deg, var(--brand-blue) 0%, var(--brand-red) 100%);
  background-origin: border-box; background-clip: padding-box, border-box;
}
.phone-mock::before{
  content:""; position:absolute; inset:0; pointer-events:none;
  background: linear-gradient(135deg, rgba(4,53,132,.18), rgba(156,0,65,.18));
  mix-blend-mode:multiply; opacity:.25;
}
.phone-mock::after{
  content:""; position:absolute; width:120px; height:120px; right:-40px; top:-40px; border-radius:50%;
  background: radial-gradient(closest-side, rgba(4,53,132,.18), transparent);
  filter: blur(8px); pointer-events:none;
}
.online-media::before{
  content:""; position:absolute; width:160px; height:160px; left:-50px; bottom:-50px; border-radius:50%;
  background: radial-gradient(closest-side, rgba(156,0,65,.18), transparent);
  filter: blur(10px); pointer-events:none;
}
.phone-mock img { width: 100%; height: auto; display: block; }

/* Stacked decorative layers around the media */
.online-media{ position:relative; }
.online-media .stack{ position:absolute; border-radius:16px; pointer-events:none; }
.online-media .stack.layer-a{ width:86%; height:84%; left:-18px; top:-18px; background: linear-gradient(135deg, rgba(4,53,132,.12), rgba(156,0,65,.12)); transform: rotate(-4deg); filter: blur(2px); }
.online-media .stack.layer-b{ width:86%; height:84%; right:-16px; bottom:-16px; background: linear-gradient(135deg, rgba(156,0,65,.10), rgba(4,53,132,.10)); transform: rotate(3deg); filter: blur(1px); }
.online-media .stack.layer-c{ width:70%; height:68%; left:8%; top:10%; background: rgba(255,255,255,.4); backdrop-filter: blur(0.5px); mix-blend-mode: overlay; border-radius:14px; }

/* Steps (flow cards) */
.steps-flow { display: grid; grid-template-columns: 1fr auto 1fr auto 1fr auto 1fr; gap: 18px; align-items: stretch; position: relative; }
.step-card { background: #fff; border: 1px solid #e2e8f0; border-radius: 16px; padding: 18px; text-align: center; box-shadow: 0 8px 18px rgba(2,6,23,.06); display: grid; gap: 8px; }
.step-icon { width: 56px; height: 56px; border-radius: 999px; background: var(--brand-blue); display: grid; place-items: center; margin: 0 auto 6px; box-shadow: 0 8px 18px rgba(11,93,170,.25); }
.step-meta { font-size: 12px; color: var(--brand-blue); font-weight: 700; letter-spacing: .4px; text-transform: uppercase; }
.step-arrow { display: grid; place-items: center; color: #94a3b8; font-size: 22px; width: 24px; }

/* FAQ */
.section-faq details { border: 1px solid #e2e8f0; border-radius: 12px; padding: 12px 16px; background: #fff; }
.section-faq details + details { margin-top: 12px; }
.section-faq summary { cursor: pointer; font-weight: 600; }
.section-faq summary::-webkit-details-marker { display: none; }

/* CTA */
.section-cta { background: linear-gradient(180deg, #f8fafc, #ffffff); }
.cta-inner { display: grid; grid-template-columns: 1.2fr 1fr; gap: 18px; align-items: center; border: 1px solid #e2e8f0; border-radius: 16px; padding: 22px; background: #ffffff; }
.cta-form .form-row { display: flex; gap: 12px; flex-wrap: wrap; }
.cta-form input, .cta-form select { flex: 1; min-width: 200px; padding: 12px 14px; border-radius: 10px; border: 1px solid #cbd5e1; }
.cta-form button { white-space: nowrap; }
.form-note { color: #64748b; font-size: 12px; margin: 8px 0 0; }

/* Footer */
.site-footer { border-top: 1px solid #e2e8f0; background: #f8fafc; }
.footer-inner { display: grid; grid-template-columns: 1.2fr 1fr 1fr; gap: 18px; padding: 24px 0; }
.footer-links nav { display: grid; gap: 8px; }
.footer-links a { color: #0f172a; text-decoration: none; }
.footer-links a:hover { text-decoration: underline; }
.footer-meta { color: #64748b; }

/* Responsive */
@media (max-width: 1024px) {
  .hero-inner { grid-template-columns: 1fr; }
  .cta-inner { grid-template-columns: 1fr; }
  .steps-flow { grid-template-columns: repeat(2, 1fr); }
  .benefit-grid { grid-template-columns: repeat(2, 1fr); }
  .course-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-inner { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 640px) {
  .nav-toggle { display: inline-block; }
  .nav-menu { display: none; position: absolute; right: 20px; top: 60px; background: #ffffff; border: 1px solid #e2e8f0; border-radius: 12px; padding: 10px; box-shadow: 0 10px 24px rgba(2,6,23,.08); }
  .nav-menu.open { display: grid; gap: 6px; }
  .course-grid { grid-template-columns: 1fr; }
  .steps-flow { grid-template-columns: 1fr; }
  .step-arrow { display: none; }
  .footer-inner { grid-template-columns: 1fr; }
  
  /* Mobile specific fixes - Reduced padding for better space utilization */
  .container { padding: 0 8px; }
  .hero { padding: 32px 0; }
  .hero h1 { font-size: 26px; line-height: 1.2; }
  .hero p { font-size: 15px; }
  .hero-actions { flex-direction: column; gap: 8px; }
  .hero-actions .btn { width: 100%; justify-content: center; }
  .hero-highlights { flex-direction: column; gap: 8px; }
  .hero-highlights li { text-align: center; }
  .benefit-grid { grid-template-columns: 1fr; gap: 12px; }
  .online-inner { grid-template-columns: 1fr; gap: 20px; }
  .online-stats { grid-template-columns: 1fr; gap: 12px; }
  .cta-inner { grid-template-columns: 1fr; gap: 20px; }
  .cta-form .form-row { flex-direction: column; gap: 8px; }
  .cta-form input, .cta-form select { min-width: auto; }
  
  /* Additional mobile optimizations */
  .section { padding: 40px 0; }
  .benefit-item { padding: 16px; }
  .course-card { padding: 14px; }
  .step-card { padding: 16px; }
  .stat { padding: 14px; }
}

/* Mobile overflow prevention */
html, body { 
  overflow-x: hidden; 
  max-width: 100vw;
}

/* Mobile-specific optimizations for better space utilization */
@media (max-width: 640px) {
  /* Reduce overall padding and margins */
  .container { 
    padding: 0 6px !important; 
    max-width: 100%;
  }
  
  /* Optimize hero section for mobile */
  .hero { 
    padding: 24px 0 !important; 
  }
  
  .hero h1 { 
    font-size: 24px !important; 
    line-height: 1.1 !important;
    margin-bottom: 12px !important;
  }
  
  .hero p { 
    font-size: 14px !important; 
    margin-bottom: 16px !important;
  }
  
  /* Optimize sections */
  .section { 
    padding: 32px 0 !important; 
  }
  
  /* Reduce card padding */
  .benefit-item, 
  .course-card, 
  .step-card, 
  .stat { 
    padding: 12px !important; 
  }
  
  /* Optimize form elements */
  .cta-form input, 
  .cta-form select { 
    padding: 10px 12px !important; 
  }
  
  /* Reduce gaps between elements */
  .benefit-grid, 
  .course-grid { 
    gap: 10px !important; 
  }
  
  .hero-highlights { 
    gap: 6px !important; 
  }
  
  .hero-highlights li { 
    padding: 6px 10px !important; 
    font-size: 13px !important;
  }
}

/* Ensure all media elements are responsive */
img, video, iframe { 
  max-width: 100%;
  height: auto;
  display: block;
}

/* Full-bleed backgrounds for sections */
.section.theme-soft-blue,
.section.theme-dots,
.section.theme-grid,
.section.theme-stripes { 
  position: relative; 
  overflow-x: hidden;
}

/* Harmonious background system - Full-bleed implementation */
/* All backgrounds now use consistent gradient base with different pattern overlays */

/* Content above background */
.section > .container,
.hero > .container { 
  position: relative; 
  z-index: 1; 
}
/* Desktop ≥ 1200px: 4 cột */
#khoa-hoc .course-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 24px; /* hoặc giá trị hiện có */
}

/* Tablet: 2 cột */
@media (max-width: 1199px) {
  #khoa-hoc .course-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* Mobile: 1 cột */
@media (max-width: 767px) {
  #khoa-hoc .course-grid {
    grid-template-columns: 1fr;
  }
}

/* Đảm bảo thẻ con không tự đặt width làm hỏng grid */
#khoa-hoc .course-grid .course-card {
  width: 100%;
}

/* Giữ tỉ lệ ảnh đồng đều (nếu cần) */
#khoa-hoc .course-grid .card-media {
  padding-top: 56.25%; /* 16:9 */
  background-size: cover;
  background-position: center;
}