*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,h5,p,ul,ol,li,figure,blockquote,dl,dd{margin:0}
ul,ol{padding:0;list-style:none}
a{color:inherit}
button{font:inherit;color:inherit}
img,svg,video{max-width:100%}
img{display:block}

:root{
  --ink:#0C1F1A;
  --ink-deep:#08150F;
  --panel:#111418;
  --paper:#F3E9D2;
  --spring:#39D98A;
  --summer:#FF8A3D;
  --autumn:#E8B84B;
  --winter:#4AA8FF;
  --cyan:#5EF2E8;
  --gold:#FFC857;
  --grid:#5B6B66;
  --line:rgba(91,107,102,.38);
  --line-soft:rgba(91,107,102,.18);
  --text:#E9F0EC;
  --text-dim:#A7B7B0;
  --paper-ink:#16211D;
  --font-display:"PingFang SC","Noto Sans SC","Source Han Sans SC","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-body:"PingFang SC","Noto Sans SC","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-mono:ui-monospace,"JetBrains Mono","Roboto Mono","SFMono-Regular",Menlo,Consolas,monospace;
  --shell:1240px;
  --gap:clamp(1rem,2.4vw,2rem);
  --radius:16px;
  --radius-lg:26px;
  --radius-pill:999px;
  --shadow-lift:0 26px 48px -32px rgba(0,0,0,.9);
}

body{
  min-height:100vh;
  background-color:var(--ink);
  background-image:
    linear-gradient(var(--line-soft) 1px,transparent 1px),
    linear-gradient(90deg,var(--line-soft) 1px,transparent 1px),
    radial-gradient(circle at 88% -12%,rgba(74,168,255,.13),transparent 58%),
    radial-gradient(circle at 6% 4%,rgba(57,217,138,.09),transparent 46%);
  background-size:64px 64px,64px 64px,100% 100%,100% 100%;
  color:var(--text);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.7;
  letter-spacing:.01em;
}

h1,h2,h3,h4{
  font-family:var(--font-display);
  font-weight:900;
  line-height:1.08;
  letter-spacing:-.02em;
}
h1{font-size:clamp(2.4rem,6vw,4.6rem)}
h2{font-size:clamp(1.6rem,3.4vw,2.6rem)}
h3{font-size:clamp(1.15rem,2vw,1.5rem)}
p{max-width:70ch}

:focus-visible{
  outline:2px solid var(--cyan);
  outline-offset:3px;
  border-radius:6px;
}

/* ---------- shell / layout ---------- */
.shell{
  width:min(var(--shell),100% - 2.5rem);
  margin-inline:auto;
}
.section{padding-block:clamp(2.5rem,6vw,5rem)}
.section-head{
  display:flex;
  flex-wrap:wrap;
  align-items:flex-end;
  gap:clamp(.75rem,2vw,1.5rem);
  margin-bottom:clamp(1.25rem,3vw,2rem);
}
.section-title{
  font-family:var(--font-display);
  font-weight:900;
  font-size:clamp(1.5rem,3vw,2.35rem);
  letter-spacing:-.02em;
}
.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:.6rem;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.22em;
  text-transform:uppercase;
  color:var(--cyan);
}
.eyebrow::before{content:"";width:26px;height:1px;background:currentColor}
.section-index{
  font-family:var(--font-mono);
  font-weight:700;
  font-size:clamp(4rem,12vw,9.5rem);
  line-height:.78;
  letter-spacing:-.04em;
  color:transparent;
  -webkit-text-stroke:1px var(--grid);
  user-select:none;
}

.grid-12{
  display:grid;
  grid-template-columns:repeat(12,minmax(0,1fr));
  gap:var(--gap);
}
.col-3{grid-column:span 3}
.col-4{grid-column:span 4}
.col-5{grid-column:span 5}
.col-6{grid-column:span 6}
.col-7{grid-column:span 7}
.col-8{grid-column:span 8}
.col-12{grid-column:span 12}

.stack{display:grid;gap:1rem;align-content:start}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums;letter-spacing:.02em}
.text-dim{color:var(--text-dim)}
.sr-only{
  position:absolute;width:1px;height:1px;padding:0;margin:-1px;
  overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0;
}

/* ---------- buttons ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:.5rem;
  padding:.62rem 1.15rem;
  border-radius:var(--radius-pill);
  border:1px solid transparent;
  font-family:var(--font-display);
  font-weight:700;
  font-size:.9rem;
  letter-spacing:.02em;
  text-decoration:none;
  cursor:pointer;
  transition:transform .18s ease,background-color .18s ease,color .18s ease,border-color .18s ease,box-shadow .18s ease;
}
.btn-primary{
  background:var(--gold);
  border-color:var(--gold);
  color:#241806;
  box-shadow:0 0 0 1px rgba(255,200,87,.22),0 14px 26px -18px rgba(255,200,87,.8);
}
.btn-primary:hover,.btn-primary:focus-visible{
  background:#FFD druck;
  background:#FFD780;
  border-color:#FFD780;
  transform:translateY(-1px);
}
.btn-ghost{
  background:transparent;
  border-color:rgba(94,242,232,.45);
  color:var(--cyan);
}
.btn-ghost:hover,.btn-ghost:focus-visible{
  background:rgba(94,242,232,.12);
  border-color:var(--cyan);
  transform:translateY(-1px);
}

/* ---------- skip link ---------- */
.skip-link{
  position:fixed;
  top:.5rem;
  left:50%;
  z-index:200;
  transform:translate(-50%,-160%);
  padding:.6rem 1.1rem;
  border-radius:var(--radius-pill);
  background:var(--cyan);
  color:var(--ink-deep);
  font-weight:700;
  font-size:.88rem;
  text-decoration:none;
  transition:transform .2s ease;
}
.skip-link:focus,.skip-link:focus-visible{transform:translate(-50%,0)}

/* ---------- header ---------- */
.site-header{
  position:sticky;
  top:0;
  z-index:80;
  background:linear-gradient(180deg,rgba(8,21,15,.985),rgba(12,31,26,.94));
  border-bottom:1px solid var(--line);
  backdrop-filter:blur(10px);
  transition:box-shadow .2s ease,background-color .2s ease;
}
.site-header[data-stuck="true"]{
  box-shadow:0 22px 38px -30px #000;
  background:linear-gradient(180deg,rgba(6,17,12,.995),rgba(12,31,26,.97));
}
.header-rail{position:relative}
.rail-inner{
  display:flex;
  align-items:center;
  gap:clamp(.75rem,2vw,1.75rem);
  padding-block:.8rem;
}
.brand{
  display:inline-flex;
  align-items:center;
  gap:.7rem;
  text-decoration:none;
  color:var(--text);
  min-width:0;
}
.brand-mark{
  flex:0 0 auto;
  width:46px;
  height:46px;
  border-radius:14px;
  display:grid;
  place-items:center;
  font-family:var(--font-mono);
  font-weight:700;
  font-size:.92rem;
  letter-spacing:.04em;
  color:#07130E;
  background:conic-gradient(from 215deg,var(--spring) 0 25%,var(--summer) 25% 50%,var(--autumn) 50% 75%,var(--winter) 75% 100%);
  box-shadow:inset 0 0 0 3px var(--ink),0 10px 20px -14px rgba(0,0,0,.9);
}
.brand-text{display:grid;gap:2px;min-width:0}
.brand-name{
  font-family:var(--font-display);
  font-weight:900;
  font-size:clamp(1rem,1.6vw,1.16rem);
  letter-spacing:.01em;
  line-height:1.1;
  white-space:nowrap;
}
.brand-sub{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.1em;
  color:var(--text-dim);
  white-space:nowrap;
}
.header-announce{
  display:inline-flex;
  align-items:center;
  gap:.5rem;
  max-width:none;
  padding:.32rem .85rem;
  border:1px solid var(--line);
  border-radius:var(--radius-pill);
  font-size:12.5px;
  letter-spacing:.04em;
  color:var(--gold);
  background:rgba(255,200,87,.07);
  white-space:nowrap;
}
.dot{
  width:8px;
  height:8px;
  border-radius:50%;
  background:var(--spring);
  box-shadow:0 0 0 3px rgba(57,217,138,.18);
  flex:0 0 auto;
}
.header-cta{margin-left:auto}

/* mobile nav toggle */
.nav-toggle{
  display:none;
  align-items:center;
  gap:.55rem;
  padding:.5rem .85rem;
  background:rgba(17,20,24,.85);
  border:1px solid var(--line);
  border-radius:var(--radius-pill);
  color:var(--text);
  font-size:.85rem;
  font-weight:700;
  cursor:pointer;
  transition:border-color .18s ease,color .18s ease;
}
.nav-toggle:hover,.nav-toggle:focus-visible{border-color:var(--cyan);color:var(--cyan)}
.nav-toggle-box{display:inline-grid;gap:4px;width:18px}
.nav-toggle-box > span{
  display:block;
  height:2px;
  border-radius:2px;
  background:currentColor;
  transition:transform .2s ease,opacity .2s ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-box > span:nth-child(1){transform:translateY(6px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-box > span:nth-child(2){opacity:0}
.nav-toggle[aria-expanded="true"] .nav-toggle-box > span:nth-child(3){transform:translateY(-6px) rotate(-45deg)}

/* track navigation */
.track-nav{
  border-top:1px solid var(--line-soft);
  background:rgba(17,20,24,.5);
}
.track-inner{
  display:flex;
  align-items:center;
  gap:clamp(.75rem,2vw,1.5rem);
  padding-block:.5rem;
}
.track-note{
  max-width:none;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.12em;
  color:var(--grid);
  white-space:nowrap;
}
.track-list{
  display:flex;
  align-items:center;
  flex-wrap:wrap;
  gap:.2rem;
  margin-left:auto;
}
.track-list a{
  display:inline-flex;
  align-items:center;
  gap:.45rem;
  padding:.42rem .78rem;
  border-radius:var(--radius-pill);
  border:1px solid transparent;
  color:var(--text-dim);
  font-size:.92rem;
  font-weight:600;
  text-decoration:none;
  transition:color .18s ease,background-color .18s ease,border-color .18s ease;
}
.lap{
  font-family:var(--font-mono);
  font-size:10.5px;
  letter-spacing:.08em;
  color:var(--grid);
  transition:color .18s ease;
}
.track-list li:nth-child(1) .lap{color:var(--spring)}
.track-list li:nth-child(2) .lap{color:var(--summer)}
.track-list li:nth-child(3) .lap{color:var(--autumn)}
.track-list li:nth-child(4) .lap{color:var(--winter)}
.track-list li:nth-child(5) .lap{color:var(--spring)}
.track-list li:nth-child(6) .lap{color:var(--summer)}
.track-list a:hover,
.track-list a:focus-visible{
  color:var(--cyan);
  background:rgba(94,242,232,.1);
  border-color:rgba(94,242,232,.32);
}
.track-list a:hover .lap,
.track-list a:focus-visible .lap{color:var(--cyan)}
.track-list a[aria-current="page"]{
  background:var(--cyan);
  border-color:var(--cyan);
  color:var(--ink-deep);
  box-shadow:0 12px 22px -18px var(--cyan);
}
.track-list a[aria-current="page"] .lap{color:#0A2B25}
.track-label{white-space:nowrap}

.track-progress{
  position:absolute;
  left:0;
  right:0;
  bottom:-1px;
  height:2px;
  background:rgba(91,107,102,.22);
  pointer-events:none;
}
.track-progress-fill{
  display:block;
  width:0;
  height:100%;
  background:linear-gradient(90deg,var(--spring),var(--summer),var(--autumn),var(--winter),var(--cyan));
  transition:width .12s linear;
}

/* ---------- breadcrumbs ---------- */
.breadcrumbs{
  font-size:13px;
  color:var(--text-dim);
  margin-bottom:clamp(1rem,2vw,1.5rem);
}
.breadcrumbs ol{display:flex;flex-wrap:wrap;align-items:center;gap:.5rem}
.breadcrumbs li{display:flex;align-items:center;gap:.5rem}
.breadcrumbs li + li::before{content:"/";color:var(--grid);font-family:var(--font-mono);font-size:11px}
.breadcrumbs a{
  color:var(--text-dim);
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color .18s ease,border-color .18s ease;
}
.breadcrumbs a:hover,.breadcrumbs a:focus-visible{color:var(--cyan);border-color:currentColor}
.breadcrumbs [aria-current="page"]{color:var(--paper)}

/* ---------- panels / prose ---------- */
.panel{
  background:var(--panel);
  border:1px solid var(--line);
  border-radius:var(--radius-lg);
  padding:clamp(1.25rem,3vw,2rem);
}
.panel--paper{
  background:var(--paper);
  color:var(--paper-ink);
  border-color:rgba(12,31,26,.16);
}
.panel--paper a{color:#0C1F1A}
.prose{max-width:40rem;line-height:1.8;font-size:1rem}
.prose h2,.prose h3{margin-bottom:.6em}
.prose p + p{margin-top:1.05em}
.prose ul,.prose ol{margin-top:.75em;display:grid;gap:.5em}
.prose li{position:relative;padding-left:1.3rem}
.prose li::before{
  content:"";
  position:absolute;
  left:0;
  top:.72em;
  width:6px;
  height:6px;
  border-radius:2px;
  background:var(--cyan);
}
.prose--paper{
  background:var(--paper);
  color:var(--paper-ink);
  border-radius:var(--radius-lg);
  padding:clamp(1.5rem,3.5vw,2.5rem);
  border:1px solid rgba(12,31,26,.16);
  max-width:44rem;
}
.prose--paper li::before{background:#0C1F1A}

/* ---------- tags / chips ---------- */
.tag{
  display:inline-flex;
  align-items:center;
  gap:.35rem;
  padding:.2rem .6rem;
  border-radius:var(--radius-pill);
  border:1px solid currentColor;
  font-size:12px;
  font-weight:700;
  letter-spacing:.04em;
  line-height:1.6;
  color:var(--text-dim);
  background:rgba(91,107,102,.12);
}
.tag--spring{color:var(--spring);background:rgba(57,217,138,.12)}
.tag--summer{color:var(--summer);background:rgba(255,138,61,.12)}
.tag--autumn{color:var(--autumn);background:rgba(232,184,75,.12)}
.tag--winter{color:var(--winter);background:rgba(74,168,255,.12)}

.chip-row{display:flex;flex-wrap:wrap;gap:.5rem}
.chip{
  appearance:none;
  cursor:pointer;
  padding:.4rem .95rem;
  border-radius:var(--radius-pill);
  border:1px solid var(--line);
  background:rgba(17,20,24,.7);
  color:var(--text-dim);
  font-family:var(--font-body);
  font-size:.85rem;
  font-weight:600;
  letter-spacing:.02em;
  transition:color .18s ease,border-color .18s ease,background-color .18s ease;
}
.chip:hover,.chip:focus-visible{color:var(--cyan);border-color:rgba(94,242,232,.55)}
.chip[aria-pressed="true"]{
  background:var(--cyan);
  border-color:var(--cyan);
  color:var(--ink-deep);
}

/* ---------- media ---------- */
.media-frame{
  position:relative;
  overflow:hidden;
  border-radius:var(--radius-lg);
  border:1px solid var(--line);
  background:linear-gradient(160deg,#12241E 0%,#0A1712 100%);
  aspect-ratio:16 / 10;
  isolation:isolate;
}
.media-frame img,.media-frame picture,.media-frame video,.media-frame svg{
  display:block;
  width:100%;
  height:100%;
  object-fit:cover;
}
.media-frame::after{
  content:"";
  position:absolute;
  inset:0;
  z-index:1;
  pointer-events:none;
  background-image:
    linear-gradient(rgba(94,242,232,.1) 1px,transparent 1px),
    linear-gradient(90deg,rgba(94,242,232,.1) 1px,transparent 1px);
  background-size:32px 32px;
  opacity:.6;
}
.media-frame--wide{aspect-ratio:21 / 9}
.media-frame--tall{aspect-ratio:4 / 5}
.media-index{
  position:absolute;
  top:.85rem;
  left:.85rem;
  z-index:2;
  padding:.18rem .55rem;
  border-radius:var(--radius-pill);
  background:rgba(8,21,15,.78);
  border:1px solid rgba(94,242,232,.5);
  color:var(--cyan);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.1em;
}
.media-caption{
  margin-top:.7rem;
  font-size:12.5px;
  color:var(--text-dim);
  letter-spacing:.02em;
}

/* ---------- footer ---------- */
.site-footer{
  position:relative;
  margin-top:clamp(3rem,7vw,6rem);
  background-color:var(--panel);
  background-image:
    linear-gradient(var(--line-soft) 1px,transparent 1px),
    linear-gradient(90deg,var(--line-soft) 1px,transparent 1px),
    radial-gradient(circle at 84% -18%,rgba(74,168,255,.16),transparent 60%),
    radial-gradient(circle at 4% 110%,rgba(232,184,75,.1),transparent 52%);
  background-size:64px 64px,64px 64px,100% 100%,100% 100%;
  border-top:1px solid var(--line);
  color:var(--text);
}
.footer-seasons{
  display:grid;
  grid-template-columns:repeat(4,1fr);
  height:6px;
}
.footer-seasons span:nth-child(1){background:var(--spring)}
.footer-seasons span:nth-child(2){background:var(--summer)}
.footer-seasons span:nth-child(3){background:var(--autumn)}
.footer-seasons span:nth-child(4){background:var(--winter)}

.footer-grid{
  display:grid;
  grid-template-columns:minmax(0,1.05fr) minmax(0,1.6fr);
  gap:clamp(1.5rem,4vw,3.5rem);
  padding-block:clamp(2.25rem,5vw,3.5rem);
}
.footer-brand{display:grid;gap:1rem;align-content:start;justify-items:start}
.footer-summary{
  max-width:34ch;
  color:var(--text-dim);
  font-size:.95rem;
  line-height:1.75;
}
.footer-cta{justify-self:start}
.footer-cols{
  display:grid;
  grid-template-columns:repeat(3,minmax(0,1fr));
  gap:1.5rem;
}
.footer-col-title{
  margin-bottom:.85rem;
  font-family:var(--font-mono);
  font-size:11.5px;
  font-weight:700;
  letter-spacing:.16em;
  text-transform:uppercase;
  color:var(--cyan);
}
.footer-links{display:grid;gap:.55rem}
.footer-links a{
  display:inline-block;
  width:fit-content;
  padding-bottom:1px;
  border-bottom:1px solid transparent;
  color:var(--text-dim);
  font-size:.92rem;
  text-decoration:none;
  transition:color .18s ease,border-color .18s ease;
}
.footer-links a:hover,.footer-links a:focus-visible{
  color:var(--cyan);
  border-color:rgba(94,242,232,.6);
}
.footer-meta{
  display:flex;
  flex-wrap:wrap;
  align-items:flex-start;
  justify-content:space-between;
  gap:1rem 2rem;
  padding-block:1.5rem 2rem;
  border-top:1px solid var(--line-soft);
}
.footer-contact{
  display:grid;
  gap:.45rem;
  font-size:.88rem;
  color:var(--text-dim);
}
.footer-contact li{display:flex;flex-wrap:wrap;gap:.6rem;max-width:52ch}
.meta-key{
  min-width:4.6em;
  font-family:var(--font-mono);
  font-size:10.5px;
  letter-spacing:.14em;
  text-transform:uppercase;
  color:var(--grid);
  padding-top:.18em;
}
.footer-legal{
  max-width:none;
  font-size:.78rem;
  letter-spacing:.02em;
  color:var(--grid);
}
.footer-year{font-family:var(--font-mono);color:var(--text-dim)}

/* ---------- reveal ---------- */
.js [data-reveal]{
  opacity:0;
  transform:translateY(12px);
  transition:opacity .5s ease,transform .5s ease;
}
.js [data-reveal].is-visible{
  opacity:1;
  transform:none;
}

/* ---------- responsive ---------- */
@media (max-width:1024px){
  .header-announce{display:none}
  .footer-grid{grid-template-columns:minmax(0,1fr)}
}
@media (max-width:900px){
  .nav-toggle{display:inline-flex}
  .header-cta{margin-left:auto}
  .track-nav{display:none}
  .track-nav[data-open]{
    display:block;
    position:absolute;
    top:100%;
    left:0;
    right:0;
    z-index:5;
    background:#0B1A15;
    border-bottom:1px solid var(--line);
    box-shadow:var(--shadow-lift);
    padding-block:1rem 1.25rem;
    max-height:calc(100vh - 4.5rem);
    overflow-y:auto;
  }
  .track-inner{flex-direction:column;align-items:stretch;gap:.75rem}
  .track-note{white-space:normal;letter-spacing:.1em;padding-top:.1rem}
  .track-list{flex-direction:column;align-items:stretch;gap:.3rem;margin-left:0}
  .track-list a{
    justify-content:flex-start;
    padding:.72rem .9rem;
    border-radius:14px;
    font-size:1rem;
    border-color:var(--line-soft);
  }
  .track-list a[aria-current="page"]{border-color:var(--cyan)}
  .grid-12{grid-template-columns:repeat(6,minmax(0,1fr))}
  .col-7{grid-column:span 6}
  .col-8{grid-column:span 6}
  .footer-cols{grid-template-columns:repeat(2,minmax(0,1fr));gap:1.25rem 1.5rem}
}
@media (max-width:600px){
  .shell{width:min(var(--shell),100% - 1.6rem)}
  .rail-inner{gap:.6rem;padding-block:.65rem}
  .brand-mark{width:40px;height:40px;border-radius:12px;font-size:.82rem}
  .brand-sub{font-size:10px}
  .header-cta{display:none}
  .nav-toggle{margin-left:auto}
  .grid-12{grid-template-columns:1fr}
  .col-3,.col-4,.col-5,.col-6,.col-7,.col-8,.col-12{grid-column:1 / -1}
  .footer-cols{grid-template-columns:1fr}
  .footer-meta{flex-direction:column}
  .media-frame--wide{aspect-ratio:16 / 11}
}
@media (max-width:380px){
  .brand-name{font-size:.95rem}
  .nav-toggle-text{display:none}
}

/* ---------- motion / contrast preferences ---------- */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }
  .js [data-reveal]{opacity:1;transform:none}
  .btn:hover,.btn:focus-visible{transform:none}
}