/* =====================================================================
   MERIDIAN · 子午  —  Design System
   A personal journal. Editorial brutalism × soft light.
   ===================================================================== */

/* ---------- 1. Tokens ---------- */
:root {
  /* palette — dark (default) */
  --void: #06060a;
  --ink: #0b0b10;
  --surface: #101018;
  --surface-2: #16161f;
  --line: rgba(236, 231, 223, 0.12);
  --line-strong: rgba(236, 231, 223, 0.26);
  --bone: #ece7df;
  --dim: #8b867e;
  --dimmer: #5d5952;
  --ember: #ff5a1f;
  --ember-soft: #ff8a4c;
  --iris: #6c5ce7;
  --jade: #38d6a4;

  --bg: var(--void);
  --fg: var(--bone);
  --muted: var(--dim);
  --accent: var(--ember);
  --card: var(--surface);

  /* type */
  --display: "Fraunces", "Instrument Serif", "Times New Roman", "Songti SC", "SimSun", serif;
  --sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --mono: "JetBrains Mono", "SFMono-Regular", ui-monospace, "Cascadia Mono", monospace;

  /* stable type scale; responsive adjustments live in explicit breakpoints */
  --step--2: 0.72rem;
  --step--1: 0.88rem;
  --step-0: 1rem;
  --step-1: 1.25rem;
  --step-2: 1.75rem;
  --step-3: 2.55rem;
  --step-4: 3.7rem;
  --step-5: 5rem;
  --step-6: 6.5rem;
  --step-7: 8.2rem;

  /* space */
  --gap: clamp(1rem, 0.6rem + 1.6vw, 2rem);
  --pad: clamp(1.15rem, 0.5rem + 4vw, 5.5rem);
  --section: clamp(5rem, 3rem + 9vw, 12rem);

  /* motion */
  --e-out: cubic-bezier(0.16, 1, 0.3, 1);
  --e-in-out: cubic-bezier(0.76, 0, 0.24, 1);
  --e-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
  --t-fast: 0.24s;
  --t: 0.55s;
  --t-slow: 1.1s;

  --radius: 2px;
  --maxw: 1600px;
}

[data-theme="light"] {
  --void: #f2efe9;
  --ink: #eae6de;
  --surface: #ffffff;
  --surface-2: #f6f3ed;
  --line: rgba(11, 11, 16, 0.13);
  --line-strong: rgba(11, 11, 16, 0.3);
  --bone: #14141a;
  --dim: #6a655e;
  --dimmer: #9b968e;
  --bg: var(--void);
  --fg: var(--bone);
  --muted: var(--dim);
  --card: var(--surface);
}

/* ---------- 2. Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; padding: 0; }
html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scrollbar-color: var(--dimmer) transparent;
}
body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  font-size: var(--step-0);
  line-height: 1.6;
  font-feature-settings: "kern", "liga", "calt", "ss01";
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
  transition: background-color 0.7s var(--e-out), color 0.7s var(--e-out);
}
img, svg, video, canvas { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
button, input, textarea, select { font: inherit; color: inherit; background: none; border: none; }
button { cursor: pointer; }
ul, ol { list-style: none; }
::selection { background: var(--accent); color: #fff; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

/* thin scrollbar */
::-webkit-scrollbar { width: 9px; height: 9px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--dimmer); border-radius: 9px; }
::-webkit-scrollbar-thumb:hover { background: var(--accent); }

/* ---------- 3. Typographic primitives ---------- */
.display {
  font-family: var(--display);
  font-weight: 300;
  font-variation-settings: "SOFT" 0, "WONK" 1, "opsz" 100;
  line-height: 0.92;
  letter-spacing: 0;
  text-wrap: balance;
}
.display em { font-style: italic; font-variation-settings: "SOFT" 60, "WONK" 1; color: var(--accent); }
.h-xl { font-size: var(--step-7); }
.h-lg { font-size: var(--step-6); }
.h-md { font-size: var(--step-5); }
.h-sm { font-size: var(--step-4); }
.h-xs { font-size: var(--step-3); }

.eyebrow {
  font-family: var(--mono);
  font-size: var(--step--2);
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--muted);
  display: flex;
  align-items: center;
  gap: 0.75em;
}
.eyebrow::before {
  content: "";
  width: 1.9em; height: 1px;
  background: var(--accent);
  flex: none;
}
.eyebrow.no-rule::before { display: none; }
.mono { font-family: var(--mono); font-size: var(--step--2); letter-spacing: 0.14em; text-transform: uppercase; }
.lede { font-size: var(--step-1); line-height: 1.5; color: var(--fg); max-width: 30ch; text-wrap: pretty; }
.dim { color: var(--muted); }
.cn { font-family: var(--sans); letter-spacing: 0.02em; }

/* ---------- 4. Layout ---------- */
.shell { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: var(--pad); }
.section { padding-block: var(--section); position: relative; }
.grid { display: grid; gap: var(--gap); grid-template-columns: repeat(12, 1fr); }
.rule { height: 1px; background: var(--line); border: 0; width: 100%; transform-origin: left; }
.stack { display: flex; flex-direction: column; }
.row { display: flex; align-items: center; gap: var(--gap); }
.between { display: flex; align-items: flex-end; justify-content: space-between; gap: var(--gap); flex-wrap: wrap; }

/* ---------- 5. Grain + vignette ---------- */
.grain {
  position: fixed; inset: -50%;
  z-index: 9000;
  pointer-events: none;
  opacity: 0.05;
  mix-blend-mode: overlay;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='200' height='200'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4'/%3E%3C/filter%3E%3Crect width='200' height='200' filter='url(%23n)'/%3E%3C/svg%3E");
  animation: grainShift 0.7s steps(3) infinite;
  will-change: transform;
}
@keyframes grainShift {
  0% { transform: translate(0, 0); }
  33% { transform: translate(-2%, 1.5%); }
  66% { transform: translate(1.5%, -1%); }
  100% { transform: translate(0, 0); }
}
.vignette {
  position: fixed; inset: 0; z-index: 8999; pointer-events: none;
  background: none;
}

/* ---------- 6. Cursor ---------- */
@media (hover: hover) and (pointer: fine) {
  body.has-cursor, body.has-cursor a, body.has-cursor button { cursor: none; }
  .cursor {
    position: fixed; top: 0; left: 0; z-index: 9500;
    pointer-events: none;
    mix-blend-mode: difference;
    opacity: 0;
    transition: opacity 0.4s;
    will-change: transform;
  }
  .cursor.live { opacity: 1; }
  .cursor__dot {
    position: absolute; width: 7px; height: 7px; margin: -3.5px;
    border-radius: 50%; background: #fff;
    transition: opacity 0.3s, transform 0.3s var(--e-out);
  }
  .cursor__ring {
    position: absolute; width: 40px; height: 40px; margin: -20px;
    border: 1px solid #fff; border-radius: 50%;
    display: grid; place-items: center;
    transition: width 0.45s var(--e-spring), height 0.45s var(--e-spring),
                margin 0.45s var(--e-spring), background-color 0.4s, border-color 0.4s;
  }
  .cursor__label {
    font-family: var(--mono); font-size: 9px; letter-spacing: 0.16em;
    text-transform: uppercase; color: #000; opacity: 0;
    transition: opacity 0.25s; white-space: nowrap;
  }
  .cursor.is-hover .cursor__ring { width: 70px; height: 70px; margin: -35px; background: rgba(255,255,255,0.12); }
  .cursor.is-media .cursor__ring { width: 92px; height: 92px; margin: -46px; background: #fff; border-color: #fff; }
  .cursor.is-media .cursor__label { opacity: 1; }
  .cursor.is-media .cursor__dot { opacity: 0; }
  .cursor.is-down .cursor__ring { width: 26px; height: 26px; margin: -13px; }
}
.cursor { display: none; }
@media (hover: hover) and (pointer: fine) { .cursor { display: block; } }

/* ---------- 7. Preloader ---------- */
.loader {
  position: fixed; inset: 0; z-index: 9800;
  background: var(--void);
  display: grid; place-items: center;
  transition: opacity 0.6s;
}
.loader__inner { width: min(78vw, 640px); text-align: center; }
.loader__word {
  font-family: var(--display); font-size: var(--step-5); letter-spacing: 0;
  overflow: hidden; display: block;
}
.loader__word span { display: block; transform: translateY(105%); }
.loader__bar { height: 1px; background: var(--line-strong); margin-top: 1.6rem; overflow: hidden; }
.loader__bar i { display: block; height: 100%; width: 0; background: var(--accent); }
.loader__num {
  font-family: var(--mono); font-size: var(--step--2); letter-spacing: 0.2em;
  color: var(--muted); margin-top: 0.8rem; display: block; text-align: right;
}
/* the intro only plays once per session */
[data-seen="1"] .loader { display: none; }
.loader.done { pointer-events: none; }
/* self-healing: if JS never boots, the loader still gets out of the way */
.loader { animation: loaderFail 0.01s linear 3.2s forwards; }
@keyframes loaderFail { to { opacity: 0; visibility: hidden; } }

/* curtain used by loader exit + page transitions */
.curtain {
  position: fixed; inset: 0; z-index: 9700; pointer-events: none;
  display: grid; grid-auto-flow: column; grid-auto-columns: 1fr;
  overflow: hidden;
}
.curtain i {
  min-width: 0;
  margin-inline: -1px;
  background: var(--ink);
  transform: scaleY(0);
  transform-origin: bottom;
  backface-visibility: hidden;
  will-change: transform;
}
.curtain.up i { transform-origin: top; }
/* entry cover — driven by the html[data-nav] flag set in <head>, so the
   incoming page is already masked on first paint. Pure CSS: a JS failure
   can never trap the visitor behind it. */
[data-nav="1"] .curtain i {
  transform: scaleY(1);
  transform-origin: top;
  animation: curtainOut 0.85s cubic-bezier(0.76, 0, 0.24, 1) forwards;
}
[data-nav="1"] .curtain i:nth-child(1) { animation-delay: 0.02s; }
[data-nav="1"] .curtain i:nth-child(2) { animation-delay: 0.07s; }
[data-nav="1"] .curtain i:nth-child(3) { animation-delay: 0.12s; }
[data-nav="1"] .curtain i:nth-child(4) { animation-delay: 0.17s; }
[data-nav="1"] .curtain i:nth-child(5) { animation-delay: 0.22s; }
[data-nav="1"] .curtain i:nth-child(6) { animation-delay: 0.27s; }
[data-nav="1"] .curtain i:nth-child(7) { animation-delay: 0.32s; }
@keyframes curtainOut { from { transform: scaleY(1); } to { transform: scaleY(0); } }

/* ---------- 8. Header ---------- */
.hdr {
  position: fixed; top: 0; left: 0; right: 0; z-index: 8000;
  padding: clamp(0.9rem, 2vw, 1.6rem) var(--pad);
  display: flex; align-items: center; justify-content: space-between;
  gap: var(--gap);
  mix-blend-mode: normal;
  transition: transform 0.6s var(--e-out), background-color 0.5s, backdrop-filter 0.5s, border-color 0.5s;
  border-bottom: 1px solid transparent;
}
.hdr.pinned { background: color-mix(in srgb, var(--bg) 72%, transparent); backdrop-filter: blur(18px) saturate(1.4); border-bottom-color: var(--line); }
.hdr.hidden { transform: translateY(-104%); }

.brand { display: flex; align-items: baseline; gap: 0.55rem; }
.brand__mark {
  width: 26px; height: 26px; flex: none; align-self: center;
  border: 1px solid var(--fg); border-radius: 50%;
  position: relative; overflow: hidden;
}
.brand__mark::after {
  content: ""; position: absolute; inset: 0;
  background: var(--accent);
  transform: translateY(52%);
  transition: transform 0.8s var(--e-out);
}
.brand:hover .brand__mark::after { transform: translateY(0); }
.brand__name { font-family: var(--display); font-size: 1.22rem; letter-spacing: 0; }
.brand__cn { font-size: var(--step--2); color: var(--muted); letter-spacing: 0.3em; }

.nav { display: flex; align-items: center; gap: clamp(1rem, 2.2vw, 2.4rem); }
.nav a {
  font-family: var(--mono); font-size: var(--step--2);
  letter-spacing: 0.16em; text-transform: uppercase;
  position: relative; padding-block: 0.3rem;
  color: var(--muted); transition: color 0.35s;
}
.nav a::after {
  content: ""; position: absolute; left: 0; bottom: 0;
  width: 100%; height: 1px; background: var(--accent);
  transform: scaleX(0); transform-origin: left;
  transition: transform 0.5s var(--e-out);
}
.nav a:hover, .nav a[aria-current="page"] { color: var(--fg); }
.nav a:hover::after, .nav a[aria-current="page"]::after { transform: scaleX(1); }
.nav a[aria-current="page"] { color: var(--fg); }

.hdr__tools { display: flex; align-items: center; gap: 0.65rem; }
.icon-btn {
  width: 38px; height: 38px; display: grid; place-items: center;
  border: 1px solid var(--line); border-radius: 50%;
  color: var(--fg);
  transition: border-color 0.4s, background-color 0.4s, transform 0.4s var(--e-spring);
}
.icon-btn:hover { border-color: var(--fg); transform: scale(1.08); }
.icon-btn svg { width: 15px; height: 15px; }
.icon-btn .sun { display: none; }
[data-theme="light"] .icon-btn .sun { display: block; }
[data-theme="light"] .icon-btn .moon { display: none; }

.burger { display: none; }
.burger i { display: block; width: 17px; height: 1px; background: var(--fg); transition: transform 0.4s var(--e-out), opacity 0.3s; }
.burger i + i { margin-top: 4px; }
body.menu-open .burger i:first-child { transform: translateY(2.5px) rotate(45deg); }
body.menu-open .burger i:last-child { transform: translateY(-2.5px) rotate(-45deg); }

/* mobile drawer */
.drawer {
  position: fixed; inset: 0; z-index: 7900;
  background: var(--ink);
  padding: 24vh var(--pad) var(--pad);
  display: flex; flex-direction: column; justify-content: space-between;
  clip-path: inset(0 0 100% 0);
  pointer-events: none;
  transition:
    clip-path 0.85s var(--e-in-out),
    visibility 0s linear 0.85s;
  visibility: hidden;
}
body.menu-open .drawer {
  clip-path: inset(0 0 0 0);
  pointer-events: auto;
  transition-delay: 0s;
  visibility: visible;
}
.drawer__nav a {
  font-family: var(--display); font-size: var(--step-4);
  display: block; padding-block: 0.18em;
  border-bottom: 1px solid var(--line);
  opacity: 0; transform: translateY(30px);
  transition: opacity 0.6s var(--e-out), transform 0.7s var(--e-out), color 0.3s;
}
body.menu-open .drawer__nav a { opacity: 1; transform: none; }
.drawer__nav a span { font-family: var(--mono); font-size: var(--step--2); color: var(--muted); margin-right: 1em; letter-spacing: 0.2em; }
.drawer__nav a:hover { color: var(--accent); }

@media (max-width: 860px) {
  .nav { display: none; }
  .burger { display: block; width: 38px; height: 38px; display: grid; place-items: center; border: 1px solid var(--line); border-radius: 50%; }
}

/* ---------- 9. Buttons / links ---------- */
.btn {
  --btn-fg: var(--fg);
  position: relative; display: inline-flex; align-items: center; gap: 0.8em;
  font-family: var(--mono); font-size: var(--step--2);
  letter-spacing: 0.18em; text-transform: uppercase;
  padding: 1.05em 1.9em;
  border: 1px solid var(--line-strong); border-radius: 100px;
  color: var(--btn-fg); overflow: hidden; isolation: isolate;
  transition: color 0.45s var(--e-out), border-color 0.45s;
}
.btn::before {
  content: ""; position: absolute; inset: 0; z-index: -1;
  background: var(--accent);
  transform: translateY(101%);
  transition: transform 0.6s var(--e-out);
}
.btn:hover { color: #fff; border-color: var(--accent); }
.btn:hover::before { transform: translateY(0); }
.btn--solid { background: var(--fg); color: var(--bg); border-color: var(--fg); }
.btn--solid::before { background: var(--accent); }
.btn--solid:hover { color: #fff; }
.btn svg { width: 13px; height: 13px; }

.link {
  position: relative; display: inline-flex; align-items: center; gap: 0.5em;
  padding-bottom: 2px;
}
.link::after {
  content: ""; position: absolute; left: 0; bottom: 0; height: 1px; width: 100%;
  background: currentColor; transform-origin: right; transform: scaleX(1);
  transition: transform 0.45s var(--e-out);
}
.link:hover::after { transform: scaleX(0); transform-origin: left; }

.arrow-link {
  display: inline-flex; align-items: center; gap: 0.7em;
  font-family: var(--mono); font-size: var(--step--2);
  letter-spacing: 0.18em; text-transform: uppercase;
}
.arrow-link i {
  width: 26px; height: 26px; border-radius: 50%; border: 1px solid var(--line-strong);
  display: grid; place-items: center; flex: none;
  transition: background-color 0.4s, border-color 0.4s, transform 0.5s var(--e-spring);
}
.arrow-link:hover i { background: var(--accent); border-color: var(--accent); transform: rotate(45deg) scale(1.1); }
.arrow-link i::after { content: "→"; font-family: var(--sans); font-size: 11px; line-height: 1; }
.arrow-link:hover i::after { color: #fff; }

/* ---------- 10. Reveal primitives ---------- */
[data-reveal] { will-change: transform, opacity; }
.r-up { opacity: 0; transform: translateY(38px); transition: opacity 0.9s var(--e-out), transform 1.05s var(--e-out); }
.r-up.in { opacity: 1; transform: none; }
.r-fade { opacity: 0; transition: opacity 1.1s var(--e-out); }
.r-fade.in { opacity: 1; }
.r-clip { clip-path: inset(0 0 100% 0); transition: clip-path 1.15s var(--e-in-out); }
.r-clip.in { clip-path: inset(0 0 0 0); }
.r-scale img, .r-scale .media__img { transform: scale(1.22); transition: transform 1.6s var(--e-out); }
.r-scale.in img, .r-scale.in .media__img { transform: scale(1); }
.r-line { transform: scaleX(0); transition: transform 1.2s var(--e-in-out); }
.r-line.in { transform: scaleX(1); }

/* char / line split */
.split-line { display: block; overflow: hidden; }
.split-line > span { display: block; transform: translateY(110%); transition: transform 1s var(--e-out); }
.in .split-line > span, .split-line.in > span { transform: none; }
.char { display: inline-block; will-change: transform; }

/* ---------- 11. Media ---------- */
.media {
  position: relative; overflow: hidden;
  background: var(--surface-2);
  border-radius: var(--radius);
}
.media::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(180deg, transparent 40%, rgba(0,0,0,0.45));
  opacity: 0; transition: opacity 0.6s;
}
.media:hover::after { opacity: 1; }
.media__img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform 1.2s var(--e-out), filter 0.8s;
}
.media:hover .media__img { transform: scale(1.045); }
.ar-1 { aspect-ratio: 1; }
.ar-43 { aspect-ratio: 4 / 3; }
.ar-34 { aspect-ratio: 3 / 4; }
.ar-169 { aspect-ratio: 16 / 9; }
.ar-32 { aspect-ratio: 3 / 2; }
.ar-tall { aspect-ratio: 2 / 3; }

/* generated gradient art (no external images needed) */
.art {
  position: relative; overflow: hidden;
  background: var(--surface-2);
  isolation: isolate;
}
.art::before, .art::after {
  content: ""; position: absolute; inset: -30%;
  background: conic-gradient(from 0deg, var(--c1), var(--c2), var(--c3), var(--c1));
  filter: blur(42px) saturate(1.3);
  animation: artSpin 22s linear infinite;
  opacity: 0.95;
}
.art::after {
  inset: 8%;
  background: radial-gradient(circle at 30% 30%, var(--c3), transparent 60%),
              radial-gradient(circle at 70% 70%, var(--c1), transparent 55%);
  filter: blur(28px);
  animation-duration: 16s; animation-direction: reverse;
  mix-blend-mode: screen; opacity: 0.7;
}
@keyframes artSpin { to { transform: rotate(360deg); } }
.art > * { position: relative; z-index: 2; }
.art--a { --c1: #ff5a1f; --c2: #2b1055; --c3: #ffb56b; }
.art--b { --c1: #6c5ce7; --c2: #0b0b10; --c3: #38d6a4; }
.art--c { --c1: #e8e2d6; --c2: #ff5a1f; --c3: #1a1a24; }
.art--d { --c1: #38d6a4; --c2: #06060a; --c3: #6c5ce7; }
.art--e { --c1: #ffd166; --c2: #ef476f; --c3: #26183f; }
.art--f { --c1: #118ab2; --c2: #073b4c; --c3: #06d6a0; }
.art__grid {
  position: absolute; inset: 0; z-index: 3; opacity: 0.35;
  background-image: linear-gradient(var(--line) 1px, transparent 1px), linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 40px 40px;
  mix-blend-mode: overlay;
}
.art__noise {
  position: absolute; inset: 0; z-index: 4; opacity: 0.18; 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='0.9' numOctaves='3'/%3E%3C/filter%3E%3Crect width='120' height='120' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ---------- 12. Marquee ---------- */
.marquee {
  --dur: 26s;
  display: flex; overflow: hidden; user-select: none;
  border-block: 1px solid var(--line);
  padding-block: clamp(0.7rem, 1.6vw, 1.4rem);
  gap: 0;
}
.marquee__track { display: flex; flex: none; gap: 2.4rem; padding-right: 2.4rem; animation: scrollX var(--dur) linear infinite; align-items: center; }
.marquee:hover .marquee__track { animation-play-state: paused; }
.marquee--rev .marquee__track { animation-direction: reverse; }
@keyframes scrollX { to { transform: translateX(-100%); } }
.marquee__item {
  font-family: var(--display); font-size: var(--step-4);
  letter-spacing: 0; display: flex; align-items: center; gap: 2.4rem;
  white-space: nowrap; color: var(--fg);
}
.marquee__item span { color: var(--accent); font-size: 0.5em; }
.marquee--sm .marquee__item { font-family: var(--mono); font-size: var(--step--1); letter-spacing: 0.2em; text-transform: uppercase; color: var(--muted); }
.marquee--outline .marquee__item {
  color: transparent; -webkit-text-stroke: 1px var(--line-strong);
}

/* ---------- 13. Footer ---------- */
.ftr { border-top: 1px solid var(--line); padding-block: clamp(3rem, 6vw, 6rem) 2rem; position: relative; }
.ftr__huge {
  font-family: var(--display); font-size: var(--step-7);
  line-height: 0.85; letter-spacing: 0;
  display: block;
}
.ftr__cols { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: var(--gap); margin-top: clamp(2.5rem, 6vw, 5rem); }
.ftr__col h4 { font-family: var(--mono); font-size: var(--step--2); letter-spacing: 0.2em; text-transform: uppercase; color: var(--muted); font-weight: 400; margin-bottom: 1.1rem; }
.ftr__col li + li { margin-top: 0.5rem; }
.ftr__col a { position: relative; transition: color 0.3s, padding-left 0.4s var(--e-out); }
.ftr__col a::before { content: "→"; position: absolute; left: -1.2em; opacity: 0; transition: opacity 0.3s; }
.ftr__col a:hover { color: var(--accent); padding-left: 0.4em; }
.ftr__col a:hover::before { opacity: 1; }
.ftr__base { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 1rem; margin-top: clamp(3rem, 7vw, 6rem); padding-top: 1.4rem; border-top: 1px solid var(--line); }
.ftr__base p { font-family: var(--mono); font-size: var(--step--2); color: var(--dimmer); letter-spacing: 0.1em; }

/* ---------- 14. Utility ---------- */
.sr { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.center { text-align: center; }
.mt-1 { margin-top: 0.6rem; } .mt-2 { margin-top: 1.2rem; } .mt-3 { margin-top: 2rem; }
.mt-4 { margin-top: 3.2rem; } .mt-5 { margin-top: clamp(3rem,7vw,6rem); }
.tabnum { font-variant-numeric: tabular-nums; }
.nowrap { white-space: nowrap; }
.sticky-top { position: sticky; top: calc(var(--pad) / 2 + 60px); }

/* scroll hint */
.scroll-hint { display: flex; align-items: center; gap: 0.8rem; font-family: var(--mono); font-size: var(--step--2); letter-spacing: 0.2em; text-transform: uppercase; color: var(--muted); }
.scroll-hint i { display: block; width: 1px; height: 46px; background: linear-gradient(var(--accent), transparent); position: relative; overflow: hidden; }
.scroll-hint i::after { content: ""; position: absolute; inset: 0; background: var(--accent); animation: hintRun 2s var(--e-in-out) infinite; }
@keyframes hintRun { 0% { transform: translateY(-100%); } 60%,100% { transform: translateY(100%); } }

/* progress bar */
.progress { position: fixed; top: 0; left: 0; height: 2px; background: var(--accent); z-index: 8500; width: 0; }

/* ---------- 15. Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
  .drawer { transition-delay: 0s !important; }
  html { scroll-behavior: auto; }
  .r-up, .r-fade { opacity: 1 !important; transform: none !important; }
  .r-clip { clip-path: none !important; }
  .split-line > span { transform: none !important; }
}