:root {
    --black: #0a0a0f;
    --deep: #0d1117;
    --card: #12161e;
    --border: #1e2530;
    --accent: #00e5ff;
    --accent2: #7c3aed;
    --accent3: #f59e0b;
    --text: #e2e8f0;
    --muted: #64748b;
    --glow: 0 0 40px rgba(0,229,255,0.15);
  }

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

  html { scroll-behavior: smooth; }

  body {
    background: var(--black);
    color: var(--text);
    font-family: 'Noto Sans SC', sans-serif;
    overflow-x: hidden;
    line-height: 1.6;
  }

  /* ── NAV ── */
  nav {
    position: fixed; top: 0; left: 0; right: 0; z-index: 100;
    display: flex; align-items: center; justify-content: space-around;
    padding: 18px 60px;
    background: rgba(10,10,15,0.85);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
  }
  .nav-logo {
    font-family: 'Space Mono', monospace;
    font-size: 1rem; color: var(--accent);
    letter-spacing: 2px;
  }
  .nav-logo span { color: var(--text); }
  .nav-links { display: flex; gap: 32px; }
  .nav-links a {
    color: var(--muted); text-decoration: none;
    font-size: 0.85rem; letter-spacing: 1px;
    transition: color 0.2s;
  }
  .nav-links a:hover { color: var(--accent); }
  .nav-cta {
    background: var(--accent); color: var(--black);
    padding: 9px 22px; border-radius: 4px;
    font-weight: 700; font-size: 0.82rem;
    text-decoration: none; letter-spacing: 1px;
    transition: opacity 0.2s;
  }
  .nav-cta:hover { opacity: 0.85; }

  /* ── HERO ── */
  .hero {
    min-height: 100vh;
    display: flex; align-items: center; justify-content: center;
    position: relative;
    overflow: hidden;
    padding: 100px 60px 60px;
  }

  .hero-grid {
    position: absolute; inset: 0;
    background-image:
      linear-gradient(rgba(0,229,255,0.04) 1px, transparent 1px),
      linear-gradient(90deg, rgba(0,229,255,0.04) 1px, transparent 1px);
    background-size: 60px 60px;
    animation: gridPulse 6s ease-in-out infinite;
  }
  @keyframes gridPulse {
    0%,100% { opacity: 0.5; } 50% { opacity: 1; }
  }

  .hero-glow {
    position: absolute;
    width: 600px; height: 600px;
    border-radius: 50%;
    filter: blur(120px);
    pointer-events: none;
  }
  .glow-blue {
    background: radial-gradient(circle, rgba(0,229,255,0.12) 0%, transparent 70%);
    top: -100px; left: -100px;
    animation: float1 8s ease-in-out infinite;
  }
  .glow-purple {
    background: radial-gradient(circle, rgba(124,58,237,0.1) 0%, transparent 70%);
    bottom: -200px; right: -100px;
    animation: float2 10s ease-in-out infinite;
  }
  @keyframes float1 { 0%,100%{transform:translate(0,0)} 50%{transform:translate(40px,30px)} }
  @keyframes float2 { 0%,100%{transform:translate(0,0)} 50%{transform:translate(-30px,-40px)} }

  .hero-content {
    position: relative; z-index: 2;
    max-width: 900px; text-align: center;
  }

  .hero-badge {
    display: inline-flex; align-items: center; gap: 8px;
    border: 1px solid rgba(0,229,255,0.3);
    background: rgba(0,229,255,0.05);
    padding: 6px 16px; border-radius: 100px;
    font-size: 0.78rem; letter-spacing: 2px;
    color: var(--accent); margin-bottom: 32px;
    animation: fadeDown 0.8s ease both;
  }
  .hero-badge::before {
    content: ''; width: 6px; height: 6px;
    background: var(--accent); border-radius: 50%;
    animation: blink 1.5s ease infinite;
  }
  @keyframes blink { 0%,100%{opacity:1} 50%{opacity:0.2} }

  .hero-title {
    font-size: clamp(2.8rem, 6vw, 5rem);
    font-weight: 900;
    line-height: 1.1;
    margin-bottom: 12px;
    animation: fadeUp 0.8s 0.2s ease both;
  }
  .hero-title .line1 { display: block; color: var(--text); }
  .hero-title .line2 {
    display: block;
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent2) 60%, var(--accent3) 100%);
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    background-clip: text;
  }

  .hero-sub {
    font-size: 1.1rem; color: var(--muted);
    max-width: 620px; margin: 0 auto 48px;
    animation: fadeUp 0.8s 0.4s ease both;
  }

  .hero-stats {
    display: flex; justify-content: center; gap: 48px;
    margin-bottom: 48px;
    animation: fadeUp 0.8s 0.5s ease both;
  }
  .stat-item { text-align: center; }
  .stat-num {
    display: block;
    font-family: 'Space Mono', monospace;
    font-size: 2rem; font-weight: 700;
    color: var(--accent);
  }
  .stat-label { font-size: 0.78rem; color: var(--muted); letter-spacing: 1px; }

  .hero-buttons {
    display: flex; justify-content: center; gap: 16px;
    animation: fadeUp 0.8s 0.6s ease both;
  }
  .btn-primary {
    background: linear-gradient(135deg, var(--accent), var(--accent2));
    color: #fff; padding: 14px 36px;
    border-radius: 6px; font-weight: 700;
    text-decoration: none; font-size: 0.95rem;
    transition: transform 0.2s, box-shadow 0.2s;
    box-shadow: 0 0 30px rgba(0,229,255,0.2);
  }
  .btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 0 40px rgba(0,229,255,0.35);
  }
  .btn-outline {
    border: 1px solid var(--border);
    color: var(--text); padding: 14px 36px;
    border-radius: 6px; font-weight: 500;
    text-decoration: none; font-size: 0.95rem;
    transition: border-color 0.2s, background 0.2s;
  }
  .btn-outline:hover { border-color: var(--accent); background: rgba(0,229,255,0.05); }

  /* ── SCROLL INDICATOR ── */
  .scroll-hint {
    position: absolute; bottom: 32px; left: 50%; transform: translateX(-50%);
    display: flex; flex-direction: column; align-items: center; gap: 8px;
    color: var(--muted); font-size: 0.72rem; letter-spacing: 2px;
    animation: fadeUp 1s 1s ease both;
  }
  .scroll-line {
    width: 1px; height: 40px;
    background: linear-gradient(to bottom, var(--accent), transparent);
    animation: scrollDown 2s ease infinite;
  }
  @keyframes scrollDown { 0%{transform:scaleY(0);transform-origin:top} 100%{transform:scaleY(1);transform-origin:top} }

  @keyframes fadeDown { from{opacity:0;transform:translateY(-20px)} to{opacity:1;transform:translateY(0)} }
  @keyframes fadeUp { from{opacity:0;transform:translateY(30px)} to{opacity:1;transform:translateY(0)} }

  /* ── SECTION COMMON ── */
  section { padding: 100px 60px; max-width: 1200px; margin: 0 auto; }
  .section-tag {
    font-family: 'Space Mono', monospace;
    font-size: 0.72rem; letter-spacing: 3px;
    color: var(--accent); margin-bottom: 12px;
    display: flex; align-items: center; gap: 12px;
  }
  .section-tag::after {
    content: ''; flex: 0 0 40px; height: 1px; background: var(--accent);
  }
  h2 {
    font-size: clamp(1.8rem, 3.5vw, 2.8rem);
    font-weight: 900; line-height: 1.2;
    margin-bottom: 16px;
  }
  .section-desc {
    color: var(--muted); font-size: 1rem;
    max-width: 580px; margin-bottom: 56px;
    line-height: 1.8;
  }

  /* ── HIGHLIGHTS ── */
  .highlights-wrap { background: var(--deep); }
  .highlights-inner { max-width: 1200px; margin: 0 auto; padding: 100px 60px; }
  .highlights-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 24px;
  }
  .hl-card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 32px;
    position: relative;
    overflow: hidden;
    transition: border-color 0.3s, transform 0.3s;
  }
  .hl-card::before {
    content: '';
    position: absolute; top: 0; left: 0; right: 0; height: 2px;
    background: linear-gradient(90deg, var(--accent), var(--accent2));
    transform: scaleX(0); transform-origin: left;
    transition: transform 0.4s ease;
  }
  .hl-card:hover { border-color: rgba(0,229,255,0.3); transform: translateY(-4px); }
  .hl-card:hover::before { transform: scaleX(1); }
  .hl-icon {
    font-size: 2rem; margin-bottom: 16px;
    width: 52px; height: 52px;
    display: flex; align-items: center; justify-content: center;
    background: rgba(0,229,255,0.08);
    border-radius: 10px;
  }
  .hl-title { font-size: 1.05rem; font-weight: 700; margin-bottom: 10px; }
  .hl-desc { color: var(--muted); font-size: 0.88rem; line-height: 1.7; }

  /* ── COURSE DAYS ── */
  .days-section { background: var(--black); }
  .days-tabs {
    display: flex; gap: 0; margin-bottom: 40px;
    border-bottom: 1px solid var(--border);
  }
  .day-tab {
    padding: 14px 32px;
    background: none; border: none;
    color: var(--muted); font-size: 0.9rem;
    font-family: 'Noto Sans SC', sans-serif;
    cursor: pointer; position: relative;
    transition: color 0.2s;
    letter-spacing: 0.5px;
  }
  .day-tab.active { color: var(--accent); }
  .day-tab.active::after {
    content: ''; position: absolute;
    bottom: -1px; left: 0; right: 0; height: 2px;
    background: var(--accent);
  }
  .day-tab:hover { color: var(--text); }

  .day-panel { display: none; }
  .day-panel.active { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }

  .day-info { }
  .day-number {
    font-family: 'Space Mono', monospace;
    font-size: 0.72rem; letter-spacing: 3px;
    color: var(--accent); margin-bottom: 10px;
  }
  .day-title { font-size: 1.5rem; font-weight: 700; margin-bottom: 16px; }
  .day-desc { color: var(--muted); font-size: 0.9rem; line-height: 1.8; margin-bottom: 24px; }
  .day-outcomes {
    display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 28px;
  }
  .outcome-tag {
    background: rgba(0,229,255,0.08);
    border: 1px solid rgba(0,229,255,0.2);
    color: var(--accent);
    padding: 4px 12px; border-radius: 100px;
    font-size: 0.78rem;
  }

  .day-modules { }
  .module-group {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    margin-bottom: 12px;
    overflow: hidden;
  }
  .module-header {
    padding: 16px 20px;
    display: flex; align-items: center; gap: 12px;
    cursor: pointer;
    transition: background 0.2s;
  }
  .module-header:hover { background: rgba(255,255,255,0.02); }
  .module-dot {
    width: 8px; height: 8px; border-radius: 50%;
    background: var(--accent); flex-shrink: 0;
  }
  .module-name { font-size: 0.92rem; font-weight: 500; flex: 1; }
  .module-arrow {
    color: var(--muted); font-size: 0.7rem;
    transition: transform 0.3s;
  }
  .module-group.open .module-arrow { transform: rotate(90deg); }
  .module-items {
    display: none;
    padding: 0 20px 14px 40px;
  }
  .module-group.open .module-items { display: block; }
  .module-item {
    color: var(--muted); font-size: 0.83rem;
    padding: 4px 0;
    display: flex; align-items: flex-start; gap: 8px;
  }
  .module-item::before {
    content: '—'; color: var(--border); flex-shrink: 0; margin-top: 1px;
  }

  /* ── CASES ── */
  .cases-wrap { background: var(--deep); }
  .cases-inner { max-width: 1200px; margin: 0 auto; padding: 100px 60px; }
  .cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 16px;
  }
  .case-card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 22px;
    transition: border-color 0.3s, transform 0.3s;
    position: relative;
    overflow: hidden;
  }
  .case-card::after {
    content: '';
    position: absolute; bottom: 0; left: 0; right: 0; height: 3px;
    background: linear-gradient(90deg, var(--accent2), var(--accent3));
    transform: scaleX(0); transform-origin: left;
    transition: transform 0.3s;
  }
  .case-card:hover { border-color: rgba(124,58,237,0.4); transform: translateY(-3px); }
  .case-card:hover::after { transform: scaleX(1); }
  .case-emoji { font-size: 1.5rem; margin-bottom: 12px; display: block; }
  .case-title { font-size: 0.88rem; font-weight: 600; line-height: 1.5; color: var(--text); }
  .case-day {
    margin-top: 10px;
    font-size: 0.72rem; color: var(--muted);
    font-family: 'Space Mono', monospace;
  }

  /* ── TECH STACK ── */
  .tech-section { }
  .tech-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 12px;
  }
  .tech-item {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 16px 20px;
    display: flex; align-items: center; gap: 12px;
    transition: border-color 0.2s;
  }
  .tech-item:hover { border-color: rgba(0,229,255,0.3); }
  .tech-icon { font-size: 1.4rem; }
  .tech-name { font-size: 0.82rem; font-weight: 500; }

  /* ── AUDIENCE ── */
  .audience-section { background: var(--deep); }
  .audience-inner { max-width: 1200px; margin: 0 auto; padding: 100px 60px; }
  .audience-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
  }
  .audience-card {
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 28px;
    position: relative;
  }
  .audience-number {
    position: absolute; top: 20px; right: 24px;
    font-family: 'Space Mono', monospace;
    font-size: 2.5rem; font-weight: 700;
    color: rgba(255,255,255,0.04);
  }
  .audience-icon { font-size: 1.8rem; margin-bottom: 16px; }
  .audience-title { font-size: 1rem; font-weight: 700; margin-bottom: 8px; }
  .audience-desc { color: var(--muted); font-size: 0.85rem; line-height: 1.7; }

  /* ── TIMELINE ── */
  .timeline-section { }
  .timeline {
    position: relative;
    padding-left: 32px;
  }
  .timeline::before {
    content: '';
    position: absolute; left: 8px; top: 8px; bottom: 8px;
    width: 1px;
    background: linear-gradient(to bottom, var(--accent), var(--accent2), var(--accent3));
  }
  .timeline-item {
    position: relative;
    margin-bottom: 40px;
    padding-left: 32px;
  }
  .timeline-dot {
    position: absolute; left: -32px; top: 6px;
    width: 14px; height: 14px;
    border-radius: 50%;
    border: 2px solid var(--accent);
    background: var(--black);
  }
  .timeline-day {
    font-family: 'Space Mono', monospace;
    font-size: 0.72rem; letter-spacing: 2px;
    color: var(--accent); margin-bottom: 6px;
  }
  .timeline-title { font-size: 1.1rem; font-weight: 700; margin-bottom: 10px; }
  .timeline-desc { color: var(--muted); font-size: 0.88rem; line-height: 1.8; }

  /* ── CTA BANNER ── */
  .cta-banner {
    background: var(--deep);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
  }
  .cta-inner {
    max-width: 1200px; margin: 0 auto;
    padding: 80px 60px;
    display: grid; grid-template-columns: 1fr auto;
    align-items: center; gap: 60px;
  }
  .cta-title { font-size: clamp(1.6rem, 3vw, 2.4rem); font-weight: 900; }
  .cta-title span { color: var(--accent); }
  .cta-desc { color: var(--muted); font-size: 0.95rem; margin-top: 12px; line-height: 1.7; }
  .cta-actions { display: flex; flex-direction: column; gap: 12px; align-items: flex-end; }
  .cta-price {
    font-family: 'Space Mono', monospace;
    font-size: 0.75rem; color: var(--muted); letter-spacing: 2px; margin-bottom: 4px;
  }

  /* ── FAQ ── */
  .faq-section { }
  .faq-list { max-width: 760px; }
  .faq-item {
    border-bottom: 1px solid var(--border);
    padding: 22px 0;
  }
  .faq-q {
    display: flex; align-items: center; justify-content: space-between;
    cursor: pointer;
    font-weight: 600; font-size: 0.95rem;
    gap: 16px;
  }
  .faq-q:hover { color: var(--accent); }
  .faq-toggle { color: var(--accent); font-size: 1.2rem; flex-shrink: 0; }
  .faq-a {
    color: var(--muted); font-size: 0.88rem;
    line-height: 1.8; padding-top: 14px;
    display: none;
  }
  .faq-item.open .faq-a { display: block; }
  .faq-item.open .faq-toggle { transform: rotate(45deg); display: inline-block; }

  /* ── FOOTER ── */
  footer {
    background: var(--black);
    border-top: 1px solid var(--border);
    padding: 48px 60px;
    display: flex; align-items: center; justify-content: space-between;
  }
  .footer-logo {
    font-family: 'Space Mono', monospace;
    font-size: 0.9rem; color: var(--accent);
  }
  .footer-logo span { color: var(--muted); }
  .footer-copy { color: var(--muted); font-size: 0.78rem; }

  /* ── FLOATING BTN ── */
  .float-btn {
    position: fixed; bottom: 120px; right: 40px; z-index: 50;
    background: linear-gradient(135deg, var(--accent), var(--accent2));
    color: #fff; padding: 14px 24px;
    border-radius: 50px; font-weight: 700; font-size: 0.88rem;
    text-decoration: none;
    box-shadow: 0 8px 30px rgba(0,229,255,0.25);
    transition: transform 0.2s, box-shadow 0.2s;
    display: flex; align-items: center; gap: 8px;
  }
  .float-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 40px rgba(0,229,255,0.35);
  }
  .float-pulse {
    width: 8px; height: 8px; border-radius: 50%;
    background: #fff;
    animation: pulse 1.5s ease infinite;
  }
  @keyframes pulse {
    0%,100%{transform:scale(1);opacity:1}
    50%{transform:scale(1.5);opacity:0.5}
  }

  /* ── RESPONSIVE ── */
  @media(max-width: 768px) {
    nav { padding: 14px 5px; }
    .nav-links { display: none; }
    section, .highlights-inner, .cases-inner, .audience-inner { padding: 60px 24px; }
    .hero { padding: 80px 24px 60px; }
    .hero-stats { gap: 24px; }
    .stat-num { font-size: 1.5rem; }
    .day-panel.active { grid-template-columns: 1fr; }
    .cta-inner { grid-template-columns: 1fr; }
    .cta-actions { align-items: flex-start; }
    footer { flex-direction: column; gap: 16px; text-align: center; }
    .float-btn { bottom: 24px; right: 24px; }
  }