/* ============================================================
   AI Engineers Academy — LAUNCH EXPERIENCE
   Cinematic scroll-journey. Theme + atmosphere shift per chapter.
   ============================================================ */
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth;background:#05060e}
body{
  background:transparent;color:var(--text);
  font-family:'Inter',system-ui,sans-serif;font-size:16px;line-height:1.6;
  -webkit-font-smoothing:antialiased;overflow-x:hidden;
  transition:color .9s var(--ease);
}
:root{
  --ease:cubic-bezier(.4,.14,.2,1);
  --maxw:1080px;
  --text:#eef2fb;--muted:#9fb0cf;--accent:#6f9cff;
}
a{color:inherit;text-decoration:none}
button{font-family:inherit;cursor:pointer;border:none;background:none;color:inherit}
::selection{background:color-mix(in srgb,var(--accent) 38%, transparent)}
::-webkit-scrollbar{width:0}

/* ── Foreground theme tokens (drive text/accent; bg comes from stage) ── */
[data-dir="a"]{--accent:#52e89f;--text:#dcf4e7;--muted:#8cae9d;--chip:rgba(82,232,159,.12);--line:rgba(120,165,142,.2);--mono-accent:#52e89f}
[data-dir="d"]{--accent:#2dd4a7;--text:#eaf1f8;--muted:#94a3b8;--chip:rgba(45,212,167,.13);--line:rgba(120,140,170,.2);--mono-accent:#2dd4a7}
[data-dir="b"]{--accent:#7aa2ff;--text:#eef3fc;--muted:#a4b4d2;--chip:rgba(122,162,255,.14);--line:rgba(125,145,185,.22);--mono-accent:#7aa2ff}
[data-dir="c"]{--accent:#3ee6ff;--text:#f2f0ff;--muted:#b7afe0;--chip:rgba(62,230,255,.14);--line:rgba(150,135,235,.28);--mono-accent:#c08bff}

h1,h2,h3{font-family:'Space Grotesk','Inter',sans-serif;font-weight:700;letter-spacing:-.025em;line-height:1.04}
.mono{font-family:'JetBrains Mono',ui-monospace,monospace}

/* ============================================================
   STAGE — fixed atmospheric background, layers cross-fade
   ============================================================ */
.stage{position:fixed;inset:0;z-index:-2;overflow:hidden}
.layer{position:absolute;inset:0;opacity:0;transform:scale(1.06);transition:opacity .85s var(--ease),transform 1.4s var(--ease);will-change:opacity,transform}
.layer.on{transform:scale(1)}
.layer.on{opacity:1}
.grain{position:fixed;inset:0;z-index:-1;pointer-events:none;opacity:.04;mix-blend-mode:overlay;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='120' height='120'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='2'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E")}

/* L0 — SPARK (terminal) */
.l-spark{background:
  radial-gradient(900px 620px at 80% -2%, rgba(82,232,159,.18), transparent 56%),
  radial-gradient(760px 560px at 12% 104%, rgba(82,232,159,.09), transparent 60%),
  radial-gradient(1100px 760px at 78% -5%, #0a1512, #05080a 62%)}
.l-spark::before{content:"";position:absolute;inset:0;
  background:
    radial-gradient(820px 520px at 80% 2%, rgba(82,232,159,.13), transparent 58%),
    linear-gradient(rgba(82,232,159,.05) 1px,transparent 1px),
    linear-gradient(90deg,rgba(82,232,159,.05) 1px,transparent 1px);
  background-size:100% 100%,32px 32px,32px 32px;
  -webkit-mask:radial-gradient(125% 110% at 50% 0%,#000 48%,transparent 100%);
          mask:radial-gradient(125% 110% at 50% 0%,#000 48%,transparent 100%)}
.l-spark::after{content:"";position:absolute;left:0;right:0;height:34%;top:0;
  background:linear-gradient(transparent,rgba(82,232,159,.08),transparent);
  animation:sweepDown 7s linear infinite}

/* L1 — CUBES (poleret terminal) */
.l-cubes{background:
  radial-gradient(880px 600px at 24% 10%, rgba(45,212,167,.20), transparent 56%),
  radial-gradient(760px 560px at 86% 92%, rgba(91,140,255,.13), transparent 60%),
  radial-gradient(1200px 820px at 22% 0%, #0e1622, #080b12 64%)}
.l-cubes::before{content:"";position:absolute;inset:-10%;opacity:.85;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='60' height='60' viewBox='0 0 60 60'%3E%3Cg fill='%2382a0c0'%3E%3Ccircle cx='15' cy='15' r='1.4' fill-opacity='.34'/%3E%3Ccircle cx='45' cy='45' r='1.4' fill-opacity='.34'/%3E%3Ccircle cx='45' cy='15' r='1' fill-opacity='.18'/%3E%3Ccircle cx='15' cy='45' r='1' fill-opacity='.18'/%3E%3C/g%3E%3C/svg%3E");
  background-size:60px 60px;animation:drift 90s linear infinite}
.l-cubes::after{content:"";position:absolute;inset:0;
  background:radial-gradient(640px 480px at 26% 16%, rgba(45,212,167,.18), transparent 60%);
  animation:breathe 9s ease-in-out infinite}

/* L2 — AURORA (poleret) */
.l-aurora{background:
  radial-gradient(900px 640px at 16% 10%, rgba(59,99,216,.34), transparent 56%),
  radial-gradient(840px 600px at 84% 26%, rgba(110,150,255,.30), transparent 56%),
  radial-gradient(820px 620px at 50% 110%, rgba(124,92,255,.28), transparent 60%),
  radial-gradient(1200px 820px at 50% 120%, #111c3a, #080d1c 62%)}
.l-aurora .blob{position:absolute;border-radius:50%;filter:blur(55px);opacity:.4;will-change:transform}
.l-aurora .b1{width:620px;height:620px;left:-8%;top:6%;background:radial-gradient(circle,#3b63d8,transparent 66%);animation:floatA 24s ease-in-out infinite}
.l-aurora .b2{width:560px;height:560px;right:-6%;top:30%;background:radial-gradient(circle,#5b8cff,transparent 66%);animation:floatB 30s ease-in-out infinite}
.l-aurora .b3{width:480px;height:480px;left:34%;bottom:-12%;background:radial-gradient(circle,#7c5cff,transparent 66%);animation:floatA 27s ease-in-out infinite reverse}

/* L3 — NEON (frontier) */
.l-neon{background:
  radial-gradient(900px 640px at 10% 4%, rgba(34,211,238,.34), transparent 54%),
  radial-gradient(880px 640px at 90% 12%, rgba(168,85,247,.34), transparent 54%),
  radial-gradient(1200px 520px at 50% 118%, rgba(34,211,238,.22), transparent 60%),
  radial-gradient(1200px 900px at 50% 8%, #0b0b20, #05060e 60%)}
.l-neon .blob{position:absolute;border-radius:50%;filter:blur(58px);opacity:.4;will-change:transform}
.l-neon .n1{width:640px;height:640px;left:-10%;top:-6%;background:radial-gradient(circle,#22d3ee,transparent 64%);animation:floatB 26s ease-in-out infinite}
.l-neon .n2{width:600px;height:600px;right:-12%;top:8%;background:radial-gradient(circle,#a855f7,transparent 64%);animation:floatA 32s ease-in-out infinite}
.l-neon .horizon{position:absolute;left:0;right:0;bottom:0;height:42%;
  background:linear-gradient(transparent, rgba(34,211,238,.16) 60%, rgba(168,85,247,.22));
  -webkit-mask:linear-gradient(transparent,#000);mask:linear-gradient(transparent,#000)}
.l-neon .stars{position:absolute;inset:0}
.l-neon .stars i{position:absolute;width:2px;height:2px;border-radius:50%;background:#cfe6ff;opacity:.5;animation:twinkle 4s ease-in-out infinite}

@keyframes sweepDown{0%{transform:translateY(-120%)}100%{transform:translateY(420%)}}
@keyframes drift{to{background-position:60px 60px}}
@keyframes breathe{0%,100%{opacity:.45}50%{opacity:.95}}
@keyframes floatA{0%,100%{transform:translate(0,0) scale(1)}50%{transform:translate(6%,-5%) scale(1.12)}}
@keyframes floatB{0%,100%{transform:translate(0,0) scale(1)}50%{transform:translate(-7%,6%) scale(1.16)}}
@keyframes twinkle{0%,100%{opacity:.18}50%{opacity:.85}}

/* ============================================================
   HEADER
   ============================================================ */
.lx-header{position:fixed;top:0;left:0;right:0;z-index:60;height:64px;display:flex;align-items:center;background:color-mix(in srgb,#05060e 62%,transparent);backdrop-filter:blur(14px) saturate(140%);-webkit-backdrop-filter:blur(14px) saturate(140%);border-bottom:1px solid var(--line);
  background:linear-gradient(180deg, rgba(5,6,14,.62), transparent);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px)}
.lx-header .inner{max-width:1280px;margin:0 auto;padding:0 26px;width:100%;display:flex;align-items:center;gap:18px}
.lx-brand{display:flex;align-items:center;gap:11px;font-family:'Space Grotesk';font-weight:700;font-size:16px;letter-spacing:-.01em}
.lx-brand .mark{width:30px;height:30px;border-radius:8px;display:grid;place-items:center;color:#04130c;font-weight:700;font-size:13px;
  background:linear-gradient(140deg,var(--accent),color-mix(in srgb,var(--accent) 55%, #fff));box-shadow:0 0 0 1px color-mix(in srgb,var(--accent) 45%, transparent),0 0 22px color-mix(in srgb,var(--accent) 40%, transparent);transition:.9s var(--ease)}
.lx-brand .ac{color:var(--accent);transition:color .9s var(--ease)}
.lx-spacer{flex:1}
.journey-switch{display:flex;gap:3px;padding:4px;border-radius:11px;background:rgba(255,255,255,.05);border:1px solid var(--line)}
.journey-switch button{display:flex;align-items:center;gap:7px;font-size:12.5px;font-weight:600;font-family:'JetBrains Mono';
  padding:7px 13px;border-radius:8px;color:var(--muted);transition:.18s;white-space:nowrap}
.journey-switch button .jd{width:8px;height:8px;border-radius:50%;background:currentColor;opacity:.45}
.journey-switch button:hover{color:var(--text)}
.journey-switch button.on{background:color-mix(in srgb,var(--accent) 18%, transparent);color:var(--accent)}
.journey-switch button.on .jd{opacity:1;box-shadow:0 0 10px var(--accent)}
.lx-enter{display:inline-flex;align-items:center;gap:8px;height:40px;padding:0 17px;border-radius:9px;font-weight:600;font-size:14px;
  background:var(--accent);color:#05060e;transition:.9s var(--ease),transform .15s,filter .15s;min-height:40px}
.lx-enter:hover{transform:translateY(-1px);filter:brightness(1.08)}
.lx-enter svg{width:16px;height:16px}
@media(max-width:860px){.journey-switch .jl{display:none}.lx-enter .el{display:none}}

/* ── chapter rail ───────────────────────────────────────────── */
.rail{position:fixed;right:26px;top:50%;transform:translateY(-50%);z-index:55;display:flex;flex-direction:column;gap:18px}
.rail button{display:flex;align-items:center;gap:11px;color:var(--muted);transition:.2s;flex-direction:row-reverse}
.rail .rl{font-family:'JetBrains Mono';font-size:11px;letter-spacing:.04em;opacity:0;transform:translateX(6px);transition:.2s;white-space:nowrap}
.rail .rd{width:9px;height:9px;border-radius:50%;border:1.5px solid currentColor;flex-shrink:0;transition:.2s}
.rail button:hover{color:var(--text)}
.rail button:hover .rl{opacity:1;transform:none}
.rail button.on{color:var(--accent)}
.rail button.on .rd{background:var(--accent);border-color:var(--accent);box-shadow:0 0 12px var(--accent);transform:scale(1.15)}
.rail button.on .rl{opacity:1;transform:none}
@media(max-width:760px){.rail{display:none}}

/* ============================================================
   CHAPTERS
   ============================================================ */
.chapter{position:relative;min-height:100vh;display:flex;align-items:center;
  padding:120px 26px;scroll-snap-align:center}
.chapter .wrap{max-width:var(--maxw);margin:0 auto;width:100%;position:relative;z-index:2}
.ch-num{position:absolute;z-index:1;font-family:'Space Grotesk';font-weight:700;
  font-size:clamp(170px,32vw,400px);line-height:.8;color:var(--accent);opacity:.06;
  right:2%;top:50%;transform:translateY(-50%);pointer-events:none;user-select:none;letter-spacing:-.04em;
  transition:color .9s var(--ease)}
.eyebrow{display:inline-flex;align-items:center;gap:9px;font-family:'JetBrains Mono';font-size:13px;font-weight:600;
  color:var(--accent);letter-spacing:.04em;margin-bottom:22px;transition:color .9s var(--ease)}
.eyebrow .cursor{display:inline-block;width:8px;height:15px;background:var(--accent);animation:blink 1.1s steps(1) infinite;transform:translateY(2px)}
@keyframes blink{0%,49%{opacity:1}50%,100%{opacity:0}}
.chapter h1{font-size:clamp(40px,6.6vw,82px);max-width:15ch}
.chapter h2{font-size:clamp(34px,5.4vw,66px);max-width:15ch}
.chapter h1 .ac,.chapter h2 .ac{color:var(--accent);transition:color .9s var(--ease)}
.chapter .lead{color:var(--muted);font-size:clamp(17px,2vw,21px);line-height:1.6;max-width:52ch;margin-top:26px;transition:color .9s var(--ease)}

/* boot console (ch0) */
.console{font-family:'JetBrains Mono';font-size:14.5px;line-height:2;color:var(--accent);margin-bottom:30px;min-height:88px;transition:color .9s var(--ease)}
.console .ln{opacity:.92}.console .dim{color:var(--muted)}
.scroll-hint{position:absolute;left:50%;bottom:38px;transform:translateX(-50%);display:flex;flex-direction:column;align-items:center;gap:9px;
  color:var(--muted);font-family:'JetBrains Mono';font-size:11px;letter-spacing:.18em;text-transform:uppercase;z-index:3}
.scroll-hint .mouse{width:22px;height:34px;border:1.5px solid var(--muted);border-radius:12px;position:relative}
.scroll-hint .mouse::after{content:"";position:absolute;left:50%;top:7px;width:3px;height:6px;border-radius:2px;background:var(--muted);transform:translateX(-50%);animation:wheel 1.6s var(--ease) infinite}
@keyframes wheel{0%{opacity:0;transform:translate(-50%,0)}40%{opacity:1}80%,100%{opacity:0;transform:translate(-50%,9px)}}

/* facet chips (ch1) */
.facets{display:flex;flex-wrap:wrap;gap:11px;margin-top:34px;max-width:60ch}
.facet{font-family:'JetBrains Mono';font-size:13.5px;font-weight:500;padding:9px 15px;border-radius:999px;
  background:var(--chip);border:1px solid var(--line);color:var(--text);transition:.9s var(--ease),transform .2s}
.facet:hover{transform:translateY(-3px) scale(1.04);border-color:var(--accent)}

/* journey demo (ch2) */
.theme-cards{display:grid;grid-template-columns:repeat(4,1fr);gap:13px;margin-top:38px}
@media(max-width:760px){.theme-cards{grid-template-columns:repeat(2,1fr)}}
.tc{padding:0;border-radius:14px;overflow:hidden;border:1px solid var(--line);background:rgba(255,255,255,.03);
  transition:.9s var(--ease),transform .22s,box-shadow .22s;cursor:pointer}
.tc:hover{transform:translateY(-5px);box-shadow:0 18px 50px rgba(0,0,0,.5)}
.tc .swatch{height:74px;display:flex;align-items:flex-end;padding:11px;gap:5px}
.tc .swatch span{width:18px;height:18px;border-radius:5px}
.tc .meta{padding:13px 15px}
.tc .tn{font-family:'Space Grotesk';font-weight:600;font-size:14.5px}
.tc .tg{font-family:'JetBrains Mono';font-size:11px;color:var(--muted);margin-top:3px}

/* stats + CTA (ch3) */
.stat-row{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;margin-top:42px;border-radius:16px;overflow:hidden;
  background:var(--line);border:1px solid var(--line)}
@media(max-width:680px){.stat-row{grid-template-columns:1fr}}
.stat{background:rgba(8,10,20,.55);backdrop-filter:blur(8px);padding:26px 24px}
.stat .sv{font-family:'Space Grotesk';font-size:clamp(32px,4vw,46px);font-weight:700;letter-spacing:-.03em;color:var(--accent);transition:color .9s var(--ease)}
.stat .sl{color:var(--muted);font-size:14px;margin-top:8px;font-family:'JetBrains Mono';transition:color .9s var(--ease)}
.cta-row{display:flex;gap:14px;margin-top:42px;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;height:54px;padding:0 28px;border-radius:12px;
  font-weight:600;font-size:16px;transition:.9s var(--ease),transform .15s,box-shadow .2s,filter .15s;min-height:48px}
.btn svg{width:19px;height:19px}
.btn-primary{background:var(--accent);color:#05060e}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 16px 44px color-mix(in srgb,var(--accent) 40%, transparent);filter:brightness(1.06)}
.btn-primary:active{transform:translateY(0) scale(.98)}
.btn-ghost{background:rgba(255,255,255,.05);border:1px solid var(--line);color:var(--text)}
.btn-ghost:hover{border-color:var(--accent);color:var(--accent)}

/* reveal */
body.reveal-ready [data-reveal]{opacity:0;transform:translateY(34px);transition:opacity .8s var(--ease),transform .8s var(--ease)}
body.reveal-ready [data-reveal].in{opacity:1;transform:none}
[data-d="1"]{transition-delay:.1s}[data-d="2"]{transition-delay:.2s}[data-d="3"]{transition-delay:.3s}[data-d="4"]{transition-delay:.4s}

/* footer */
.lx-footer{position:relative;z-index:2;padding:40px 26px;border-top:1px solid var(--line);
  color:var(--muted);font-size:13px;font-family:'JetBrains Mono'}
.lx-footer .fi{max-width:1280px;margin:0 auto;display:flex;justify-content:space-between;gap:20px;flex-wrap:wrap;align-items:center}
.lx-footer a{color:var(--muted)}.lx-footer a:hover{color:var(--accent)}

/* video chapter */
.lx-video{position:relative;max-width:760px;margin-top:34px;border-radius:16px;overflow:hidden;border:1px solid var(--line);
  box-shadow:0 24px 70px rgba(0,0,0,.5);aspect-ratio:16/9;background:linear-gradient(160deg, rgba(255,255,255,.05), rgba(0,0,0,.35))}
.lx-video video{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.lx-video-ov{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:14px;cursor:pointer;
  background:radial-gradient(420px 280px at 50% 45%, rgba(0,0,0,.15), rgba(4,6,12,.5));transition:opacity .4s var(--ease);z-index:2}
.lx-video.playing .lx-video-ov{opacity:0;pointer-events:none}
.lx-play{width:74px;height:74px;border-radius:50%;display:grid;place-items:center;background:var(--accent);color:#05060e;
  box-shadow:0 0 0 10px color-mix(in srgb,var(--accent) 16%, transparent),0 14px 40px color-mix(in srgb,var(--accent) 40%, transparent);transition:transform .2s var(--ease)}
.lx-play:hover{transform:scale(1.07)}.lx-play svg{width:28px;height:28px;margin-left:3px}
.lx-vcap{font-family:'JetBrains Mono';font-size:12px;color:var(--text);background:rgba(8,10,18,.5);padding:5px 12px;border-radius:999px;border:1px solid var(--line)}

@media(prefers-reduced-motion:reduce){*{animation:none!important;scroll-behavior:auto!important}
  html{scroll-snap-type:none}.layer{transition:opacity .3s}}
@media(max-width:760px){.chapter{scroll-snap-align:none}}

/* dramatic theme-change flash + pulse */
#lx-flash{position:fixed;inset:0;z-index:-1;opacity:0;pointer-events:none}
#lx-flash.go{animation:lxFlash 1.1s var(--ease)}
@keyframes lxFlash{0%{opacity:0}18%{opacity:.9}100%{opacity:0}}
body.theme-pulse main{animation:themePulse 1.2s var(--ease)}
@keyframes themePulse{0%{filter:saturate(1)}30%{filter:saturate(1.5) brightness(1.06)}100%{filter:saturate(1)}}
/* user guide hint */
.lx-guide{position:fixed;left:50%;bottom:26px;transform:translateX(-50%);z-index:58;display:flex;align-items:center;gap:9px;
  font-family:'JetBrains Mono';font-size:12px;color:var(--text);background:color-mix(in srgb,#05060e 70%,transparent);
  backdrop-filter:blur(10px);border:1px solid var(--line);border-radius:999px;padding:9px 16px;animation:guidePulse 2.4s ease-in-out infinite}
.lx-guide b{color:var(--accent)}.lx-guide.hide{display:none}
@keyframes guidePulse{0%,100%{box-shadow:0 0 0 0 color-mix(in srgb,var(--accent) 30%,transparent)}50%{box-shadow:0 0 0 7px transparent}}
@media(max-width:760px){.lx-guide{font-size:11px;padding:8px 13px}}
.lx-libcta{display:flex;gap:14px;flex-wrap:wrap;margin-top:22px}
.lx-libcta a{display:inline-flex;align-items:center;gap:8px;font-family:'JetBrains Mono';font-size:13px;color:var(--accent);border:1px solid color-mix(in srgb,var(--accent) 35%,var(--line));border-radius:10px;padding:9px 15px;transition:.15s}
.lx-libcta a:hover{background:color-mix(in srgb,var(--accent) 12%,transparent);transform:translateY(-1px)}