:root {
    --ink:#0a1628; --deep:#071020; --teal:#00c4a7; --teal-dim:#009e86;
    --amber:#f5a623; --slate:#1e3a5f; --white:#f9fbfc; --gray:#8fa8c0;
    --mono:'Space Mono',monospace; --sans:'Sora',sans-serif;
  }
  * { margin:0; padding:0; box-sizing:border-box; }
  body { background:var(--deep); color:var(--white); font-family:var(--sans); overflow-x:hidden; }
  nav { position:fixed; top:0; left:0; right:0; z-index:999; display:flex; align-items:center; justify-content:space-between; padding:1rem 4rem; background:rgba(7,16,32,0.9); backdrop-filter:blur(12px); border-bottom:1px solid rgba(0,196,167,0.15); }
  .nav-logo { font-family:var(--mono); font-size:1.1rem; color:var(--teal); text-decoration:none; letter-spacing:0.08em; }
  .nav-logo span { color:var(--white); }
  .nav-links { display:flex; gap:2rem; list-style:none; }
  .nav-links a { color:var(--gray); text-decoration:none; font-size:0.85rem; font-weight:600; letter-spacing:0.1em; text-transform:uppercase; transition:color 0.2s; }
  .nav-links a:hover { color:var(--teal); }
  .nav-cta { background:var(--teal); color:var(--deep)!important; padding:0.5rem 1.2rem; border-radius:4px; font-weight:700!important; }

  /* HERO */
  .course-hero {
    min-height:60vh; padding:8rem 4rem 4rem;
    background:linear-gradient(135deg, #2a1a0a, #5a3010);
    position:relative; overflow:hidden;
    display:grid; grid-template-columns:1fr 1fr; gap:4rem; align-items:center;
  }
  .course-hero::before { content:''; position:absolute; inset:0; background:linear-gradient(to right, rgba(7,16,32,0.85) 50%, rgba(7,16,32,0.3) 100%); }
  .course-hero-grid { position:absolute; inset:0; background-image:linear-gradient(rgba(0,196,167,0.04) 1px,transparent 1px),linear-gradient(90deg,rgba(0,196,167,0.04) 1px,transparent 1px); background-size:60px 60px; pointer-events:none; }
  .hero-left { position:relative; z-index:1; }
  .breadcrumb { display:flex; align-items:center; gap:0.5rem; font-size:0.78rem; color:var(--gray); margin-bottom:1.5rem; font-family:var(--mono); }
  .breadcrumb a { color:var(--gray); text-decoration:none; } .breadcrumb a:hover { color:var(--teal); }
  .breadcrumb span { color:rgba(255,255,255,0.3); }
  .course-badge { display:inline-block; background:#00c4a7; color:#071020; font-family:var(--mono); font-size:0.65rem; font-weight:700; padding:0.25rem 0.75rem; border-radius:3px; letter-spacing:0.12em; margin-bottom:1rem; }
  .course-hero h1 { font-size:clamp(1.8rem,3.5vw,2.8rem); font-weight:800; letter-spacing:-0.02em; line-height:1.15; margin-bottom:0.75rem; }
  .course-subtitle { color:var(--teal); font-size:1rem; margin-bottom:1.25rem; }
  .course-hero p { color:var(--gray); line-height:1.8; font-size:0.95rem; margin-bottom:2rem; }
  .hero-meta { display:flex; gap:2rem; flex-wrap:wrap; margin-bottom:2rem; }
  .meta-item { display:flex; flex-direction:column; gap:0.2rem; }
  .meta-label { font-family:var(--mono); font-size:0.62rem; color:var(--gray); letter-spacing:0.15em; text-transform:uppercase; }
  .meta-value { font-size:0.9rem; font-weight:700; color:var(--white); }
  .hero-tags { display:flex; flex-wrap:wrap; gap:0.4rem; }
  .htag { background:rgba(0,0,0,0.4); border:1px solid rgba(255,255,255,0.15); color:var(--gray); padding:0.25rem 0.7rem; border-radius:3px; font-size:0.72rem; font-family:var(--mono); }

  /* STICKY CARD */
  .hero-right { position:relative; z-index:1; }
  .price-card {
    background:var(--ink); border:1px solid rgba(0,196,167,0.25);
    border-radius:8px; overflow:hidden;
    box-shadow:0 24px 64px rgba(0,0,0,0.5);
  }
  .price-card-top { padding:1.5rem 2rem; border-bottom:1px solid rgba(255,255,255,0.07); }
  .price-big { font-family:var(--mono); font-size:2.5rem; color:var(--teal); font-weight:700; }
  .price-old { font-size:1rem; color:var(--gray); text-decoration:line-through; margin-left:0.75rem; }
  .price-save { font-size:0.78rem; color:var(--amber); background:rgba(245,166,35,0.1); padding:0.2rem 0.5rem; border-radius:3px; margin-left:0.5rem; }
  .price-card-body { padding:1.5rem 2rem; }
  .btn-enroll { display:block; background:var(--teal); color:var(--deep); font-family:var(--sans); font-weight:700; font-size:1rem; padding:1rem; border-radius:4px; text-align:center; text-decoration:none; margin-bottom:1rem; transition:all 0.2s; cursor:pointer; border:none; width:100%; }
  .btn-enroll:hover { background:var(--teal-dim); }
  .guarantee { text-align:center; font-size:0.78rem; color:var(--gray); margin-bottom:1.5rem; }
  .includes { list-style:none; }
  .includes li { font-size:0.85rem; color:var(--gray); padding:0.4rem 0; border-bottom:1px solid rgba(255,255,255,0.05); display:flex; align-items:center; gap:0.6rem; }
  .includes li::before { content:'\\2192'; color:var(--teal); font-weight:700; flex-shrink:0; }

  /* VIDEO SECTION */
  .video-section { padding:5rem 4rem; background:var(--ink); }
  .section-inner { max-width:1100px; margin:0 auto; }
  .section-tag { font-family:var(--mono); font-size:0.72rem; color:var(--teal); letter-spacing:0.25em; text-transform:uppercase; margin-bottom:1rem; display:flex; align-items:center; gap:0.75rem; }
  .section-tag::before { content:''; display:inline-block; width:2rem; height:1px; background:var(--teal); }
  h2 { font-size:1.8rem; font-weight:800; margin-bottom:2rem; }
  h2 em { font-style:normal; color:var(--teal); }

  .video-wrapper {
    position:relative; width:100%; max-width:800px; margin:0 auto;
    border-radius:8px; overflow:hidden;
    border:1px solid rgba(0,196,167,0.2);
    box-shadow:0 16px 64px rgba(0,0,0,0.5);
  }
  .video-wrapper::before { content:''; display:block; padding-top:56.25%; }
  .video-wrapper iframe {
    position:absolute; top:0; left:0; width:100%; height:100%;
    border:none;
  }
  .video-placeholder {
    position:absolute; top:0; left:0; width:100%; height:100%;
    background:linear-gradient(135deg, #2a1a0a, #5a3010);
    display:flex; flex-direction:column; align-items:center; justify-content:center;
    gap:1rem; cursor:pointer;
  }
  .play-btn {
    width:72px; height:72px; border-radius:50%;
    background:rgba(0,196,167,0.9); display:flex; align-items:center; justify-content:center;
    font-size:1.8rem; transition:transform 0.2s; text-decoration:none;
  }
  .play-btn:hover { transform:scale(1.1); }
  .video-label { font-family:var(--mono); font-size:0.78rem; color:var(--gray); letter-spacing:0.1em; }
  .yt-link { font-family:var(--mono); font-size:0.75rem; color:var(--teal); text-decoration:none; margin-top:0.5rem; }
  .yt-link:hover { text-decoration:underline; }

  /* WHAT YOU LEARN */
  .learn-section { padding:5rem 4rem; background:var(--deep); }
  .learn-grid { display:grid; grid-template-columns:1fr 1fr; gap:1rem; margin-top:2rem; }
  .learn-item { display:flex; align-items:flex-start; gap:0.75rem; padding:1rem; background:var(--ink); border:1px solid rgba(0,196,167,0.08); border-radius:4px; }
  .learn-check { color:var(--teal); font-size:1rem; flex-shrink:0; margin-top:0.1rem; }
  .learn-text { font-size:0.875rem; color:var(--gray); line-height:1.6; }

  /* CURRICULUM */
  .curriculum { padding:5rem 4rem; background:var(--ink); }
  .section-list { margin-top:2rem; }
  .sec-item { border:1px solid rgba(255,255,255,0.07); border-radius:4px; overflow:hidden; margin-bottom:0.75rem; }
  .sec-header { padding:1rem 1.5rem; background:rgba(255,255,255,0.03); display:flex; justify-content:space-between; align-items:center; cursor:pointer; user-select:none; }
  .sec-header:hover { background:rgba(0,196,167,0.05); }
  .sec-title { font-size:0.9rem; font-weight:700; }
  .sec-toggle { color:var(--teal); font-size:1.2rem; transition:transform 0.2s; }
  .sec-item.open .sec-toggle { transform:rotate(45deg); }
  .sec-lessons { display:none; padding:0.5rem 0; border-top:1px solid rgba(255,255,255,0.05); }
  .sec-item.open .sec-lessons { display:block; }
  .lesson-row { padding:0.6rem 1.5rem; display:flex; align-items:center; gap:0.75rem; font-size:0.85rem; color:var(--gray); border-bottom:1px solid rgba(255,255,255,0.04); }
  .lesson-icon { color:var(--teal); opacity:0.7; font-size:0.75rem; flex-shrink:0; }

  /* REQUIREMENTS */
  .req-section { padding:5rem 4rem; background:var(--deep); }
  .req-list { list-style:none; margin-top:1.5rem; }
  .req-list li { font-size:0.875rem; color:var(--gray); padding:0.6rem 0; border-bottom:1px solid rgba(255,255,255,0.06); display:flex; align-items:center; gap:0.75rem; }
  .req-list li::before { content:'\\2192'; color:var(--teal); font-size:0.5rem; }

  /* INSTRUCTOR */
  .instructor { padding:5rem 4rem; background:var(--ink); }
  .instructor-card { background:var(--deep); border:1px solid rgba(0,196,167,0.15); border-radius:8px; padding:2rem; display:flex; gap:2rem; align-items:flex-start; max-width:700px; }
  .instr-photo { width:80px; height:80px; border-radius:50%; background:linear-gradient(135deg, var(--slate), #2b5180); display:flex; align-items:center; justify-content:center; font-size:2rem; flex-shrink:0; border:2px solid rgba(0,196,167,0.3); }
  .instr-name { font-size:1.1rem; font-weight:700; margin-bottom:0.25rem; }
  .instr-title { font-size:0.83rem; color:var(--teal); font-family:var(--mono); margin-bottom:0.75rem; }
  .instr-bio { font-size:0.875rem; color:var(--gray); line-height:1.75; }

  /* RELATED */
  .related { padding:5rem 4rem; background:var(--deep); }
  .related-grid { display:grid; grid-template-columns:repeat(3,1fr); gap:1.5rem; margin-top:2rem; }
  .rel-card { background:var(--ink); border:1px solid rgba(0,196,167,0.1); border-radius:6px; padding:1.5rem; text-decoration:none; color:inherit; transition:all 0.3s; display:block; }
  .rel-card:hover { border-color:rgba(0,196,167,0.35); transform:translateY(-3px); }
  .rel-emoji { font-size:2rem; margin-bottom:0.75rem; display:block; }
  .rel-title { font-size:0.9rem; font-weight:700; margin-bottom:0.4rem; line-height:1.35; }
  .rel-price { font-family:var(--mono); font-size:0.9rem; color:var(--teal); }

  footer { background:var(--deep); border-top:1px solid rgba(0,196,167,0.1); padding:3rem 4rem; display:flex; justify-content:space-between; align-items:center; flex-wrap:wrap; gap:1.5rem; }
  .footer-logo { font-family:var(--mono); color:var(--teal); font-size:1rem; text-decoration:none; }
  .footer-copy { color:var(--gray); font-size:0.8rem; }
  .footer-links { display:flex; gap:1.5rem; }
  .footer-links a { color:var(--gray); text-decoration:none; font-size:0.8rem; transition:color 0.2s; }
  .footer-links a:hover { color:var(--teal); }

  @media(max-width:900px) {
    nav { padding:1rem 2rem; } .nav-links { display:none; }
    .course-hero { grid-template-columns:1fr; padding:7rem 2rem 3rem; }
    .hero-right { display:none; }
    .video-section,.learn-section,.curriculum,.req-section,.instructor,.related { padding:3rem 2rem; }
    .learn-grid,.related-grid { grid-template-columns:1fr; }
    footer { flex-direction:column; align-items:flex-start; padding:2rem; }
  }