/* ==========================================================================
   壹乐游艺 · 共享外壳样式  /assets/site.css
   ========================================================================== */

:root {
  --ink-900: #0B1020;
  --ink-800: #141B33;
  --violet: #7A5CFF;
  --magenta: #FF4D8D;
  --cyan: #2FE0C8;
  --amber: #FFA53D;
  --paper: #E8ECF5;
  --mute: #8D96B2;

  --grad-cyan-violet: linear-gradient(135deg, #2FE0C8 0%, #7A5CFF 100%);
  --grad-edge: linear-gradient(90deg, rgba(47, 224, 200, .7), rgba(122, 92, 255, .5) 42%, rgba(255, 77, 141, 0) 88%);

  --font-display: "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", ui-monospace, "Cascadia Mono", Consolas, "Liberation Mono", monospace;

  --rail-w: 76px;
  --topbar-h: 62px;
  --content-max: 1180px;

  --radius-lg: 28px;
  --radius-md: 20px;
  --radius-sm: 14px;
  --radius-pill: 999px;

  --dur: 200ms;
  --ease: cubic-bezier(.2, .7, .3, 1);
}

/* ------------------------------ reset ---------------------------------- */

*,
*::before,
*::after { box-sizing: border-box; }

html {
  background-color: var(--ink-900);
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  padding-left: var(--rail-w);
  background-color: transparent;
  color: var(--paper);
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 400;
  line-height: 1.85;
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(110% 70% at 78% -8%, rgba(122, 92, 255, .18), transparent 62%),
    radial-gradient(80% 55% at -6% 104%, rgba(47, 224, 200, .10), transparent 62%),
    radial-gradient(70% 45% at 50% 116%, rgba(255, 165, 61, .07), transparent 60%);
}

h1, h2, h3, h4, h5 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -.02em;
}

p { margin: 0 0 1.1em; }
p:last-child { margin-bottom: 0; }

ul, ol { margin: 0; padding: 0; list-style: none; }

a { color: inherit; text-decoration: none; }

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
}

img, svg, video { display: block; max-width: 100%; }

hr { border: 0; }

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

#main-content { display: block; scroll-margin-top: 24px; }

/* --------------------------- 排版工具类 -------------------------------- */

.display-xl {
  font-size: clamp(44px, 8.6vw, 96px);
  line-height: 1.02;
  letter-spacing: -.02em;
  font-stretch: semi-condensed;
}

.display-lg {
  font-size: clamp(34px, 5vw, 60px);
  line-height: 1.08;
  letter-spacing: -.02em;
  font-stretch: semi-condensed;
}

.display-md {
  font-size: clamp(24px, 3.2vw, 38px);
  line-height: 1.18;
}

.lede {
  max-width: 42ch;
  font-size: clamp(16px, 1.5vw, 18px);
  line-height: 1.9;
  color: var(--mute);
}

.mono {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--mute);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.eyebrow::before {
  content: "";
  width: 26px;
  height: 2px;
  border-radius: 2px;
  background: var(--grad-cyan-violet);
}

.v-note {
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .3em;
  color: var(--mute);
  text-transform: uppercase;
}

/* ---------------------------- 布局工具类 -------------------------------- */

.shell {
  width: 100%;
  max-width: var(--content-max);
  margin-inline: auto;
  padding-inline: clamp(20px, 4vw, 48px);
}

.section { padding-block: clamp(44px, 6vw, 84px); }

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: clamp(24px, 3vw, 40px);
}

.rule {
  height: 1px;
  background: linear-gradient(90deg, rgba(141, 150, 178, .34), rgba(141, 150, 178, 0));
}

.grid {
  display: grid;
  gap: clamp(18px, 2.4vw, 30px);
}

.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }

.grid--stagger > *:nth-child(even) { translate: 0 var(--stagger, 32px); }

/* ------------------------------ 按钮 ----------------------------------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 24px;
  border-radius: var(--radius-pill);
  border: 1px solid rgba(141, 150, 178, .2);
  background: var(--ink-800);
  color: var(--paper);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: .02em;
  transition: transform var(--dur) var(--ease),
              box-shadow var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              background-color var(--dur) var(--ease);
}

.btn:hover {
  transform: translateY(-2px);
  border-color: rgba(122, 92, 255, .6);
  box-shadow: 0 10px 26px rgba(122, 92, 255, .24);
}

.btn:active { transform: translateY(0); }

.btn--primary {
  background: var(--grad-cyan-violet);
  color: #0B1020;
  border-color: transparent;
  box-shadow: 0 10px 30px rgba(122, 92, 255, .28);
}

.btn--primary:hover { box-shadow: 0 14px 36px rgba(122, 92, 255, .44); }

.btn--ghost {
  background: transparent;
  border-color: rgba(141, 150, 178, .34);
  color: var(--paper);
}

.btn--ghost:hover { border-color: rgba(47, 224, 200, .7); }

.btn--sm { padding: 9px 18px; font-size: 13px; }

/* --------------------------- 标签 / 角标 -------------------------------- */

.chip {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 5px 14px;
  border-radius: var(--radius-pill);
  border: 1px solid rgba(141, 150, 178, .18);
  background: rgba(141, 150, 178, .12);
  color: var(--mute);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  transition: color var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              background-color var(--dur) var(--ease);
}

.chip--cyan { color: var(--cyan); border-color: rgba(47, 224, 200, .4); background: rgba(47, 224, 200, .1); }
.chip--violet { color: #B3A4FF; border-color: rgba(122, 92, 255, .45); background: rgba(122, 92, 255, .12); }
.chip--amber { color: var(--amber); border-color: rgba(255, 165, 61, .4); background: rgba(255, 165, 61, .1); }
.chip--magenta { color: #FF87B3; border-color: rgba(255, 77, 141, .42); background: rgba(255, 77, 141, .12); }

.chip--grad {
  background: var(--grad-cyan-violet);
  border-color: transparent;
  color: #0B1020;
  font-weight: 700;
}

.chip:hover { border-color: currentColor; }

.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  border-radius: 8px;
  background: var(--magenta);
  color: #0B1020;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .1em;
}

.badge--soft {
  background: rgba(255, 77, 141, .16);
  color: #FF87B3;
}

/* ------------------------------ 卡片 ----------------------------------- */

.card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: clamp(20px, 2.4vw, 30px);
  border-radius: var(--radius-lg);
  border: 1px solid rgba(141, 150, 178, .16);
  background: linear-gradient(160deg, rgba(20, 27, 51, .94), rgba(11, 16, 32, .94));
  transition: transform var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              box-shadow var(--dur) var(--ease);
}

.card:hover {
  transform: translateY(-4px);
  border-color: rgba(122, 92, 255, .62);
  box-shadow: 0 18px 44px rgba(122, 92, 255, .22);
}

.card__label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--mute);
}

.card__title { font-size: clamp(20px, 2.2vw, 26px); }

.card__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mute);
}

.card__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: auto;
  padding-top: 4px;
}

/* ----------------------------- 面包屑 ---------------------------------- */

.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--mute);
}

.crumbs__item { color: var(--mute); }
.crumbs__item a { color: var(--mute); transition: color var(--dur) var(--ease); }
.crumbs__item a:hover { color: var(--cyan); }
.crumbs__sep { color: rgba(141, 150, 178, .5); }
.crumbs [aria-current="page"] { color: var(--paper); }

/* --------------------------- 图片容器基类 ------------------------------- */

.figure {
  display: grid;
  gap: 12px;
  margin: 0;
}

.figure__media {
  position: relative;
  aspect-ratio: 16 / 10;
  overflow: hidden;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(141, 150, 178, .16);
  background:
    linear-gradient(135deg, rgba(122, 92, 255, .28), rgba(47, 224, 200, .16)),
    var(--ink-800);
}

.figure__media > img,
.figure__media > video,
.figure__media > svg,
.figure__media > picture {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.figure__media::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: .35;
  background-image:
    linear-gradient(rgba(47, 224, 200, .16) 1px, transparent 1px),
    linear-gradient(90deg, rgba(47, 224, 200, .16) 1px, transparent 1px);
  background-size: 46px 46px;
}

.figure__caption {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--mute);
}

.figure--wide .figure__media { aspect-ratio: 21 / 9; }
.figure--tall .figure__media { aspect-ratio: 4 / 5; }
.figure--square .figure__media { aspect-ratio: 1 / 1; }

/* ==========================================================================
   头部
   ========================================================================== */

.skip-link {
  position: absolute;
  top: -120px;
  left: 12px;
  z-index: 200;
  padding: 12px 20px;
  border-radius: 0 0 var(--radius-sm) var(--radius-sm);
  background: var(--cyan);
  color: #0B1020;
  font-weight: 700;
  transition: top var(--dur) var(--ease);
}

.skip-link:focus { top: 0; }

.site-header {
  position: relative;
  z-index: 60;
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: var(--rail-w);
  right: 0;
  height: 3px;
  z-index: 90;
  background: rgba(141, 150, 178, .1);
  pointer-events: none;
}

.scroll-progress__bar {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--cyan), var(--violet) 55%, var(--magenta));
}

/* ------------------------------ 顶部条 ---------------------------------- */

.topbar { display: none; }

.topbar__brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.topbar__mark,
.footer__mark,
.rail-brand__glyph {
  display: grid;
  place-items: center;
  border-radius: 12px;
  background: var(--grad-cyan-violet);
  color: #0B1020;
  font-family: var(--font-display);
  font-weight: 900;
}

.topbar__mark { width: 30px; height: 30px; font-size: 14px; border-radius: 10px; }

.topbar__name {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 900;
  letter-spacing: .06em;
}

.topbar__side {
  display: inline-flex;
  align-items: center;
  gap: 12px;
}

.topbar__pulse {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 10px rgba(47, 224, 200, .9);
}

.topbar__meta {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--mute);
}

.nav-toggle {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 8px 14px 8px 16px;
  border-radius: var(--radius-pill);
  border: 1px solid rgba(122, 92, 255, .45);
  background: rgba(122, 92, 255, .14);
  color: var(--paper);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .06em;
  transition: background-color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.nav-toggle:hover { background: rgba(122, 92, 255, .26); }

.nav-toggle__bars,
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  display: block;
  width: 16px;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
}

.nav-toggle__bars { position: relative; transition: background-color var(--dur) var(--ease); }

.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  transition: top var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.nav-toggle__bars::before { top: -5px; }
.nav-toggle__bars::after { top: 5px; }

.site-header[data-open] .nav-toggle__bars { background: transparent; }
.site-header[data-open] .nav-toggle__bars::before { top: 0; transform: rotate(45deg); }
.site-header[data-open] .nav-toggle__bars::after { top: 0; transform: rotate(-45deg); }

.nav-scrim { display: none; }

/* ---------------------------- 侧边轨道导航 ------------------------------ */

.nav-shell {
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  width: var(--rail-w);
  z-index: 70;
  border-right: 1px solid rgba(141, 150, 178, .16);
  background: linear-gradient(180deg, rgba(20, 27, 51, .96), rgba(11, 16, 32, .99));
  backdrop-filter: blur(12px);
  transition: transform var(--dur) var(--ease);
}

.nav-shell__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
  height: 100%;
  padding: 22px 0 18px;
  overflow-y: auto;
  scrollbar-width: none;
}

.nav-shell__inner::-webkit-scrollbar { display: none; }

.rail-brand {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  width: 100%;
  padding-bottom: 14px;
  border-bottom: 1px solid rgba(141, 150, 178, .18);
}

.rail-brand__glyph { width: 34px; height: 34px; font-size: 16px; }

.rail-brand__word {
  writing-mode: vertical-rl;
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 900;
  letter-spacing: .22em;
  color: var(--paper);
}

.rail-nav {
  flex: 1;
  display: flex;
  justify-content: center;
  width: 100%;
}

.rail-nav__list {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
}

.rail-nav__item { display: flex; }

.rail-nav__link {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 7px;
  padding: 9px 6px;
  border-radius: 10px;
  color: var(--mute);
  transition: color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.rail-nav__num {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .08em;
  opacity: .7;
}

.rail-nav__text {
  writing-mode: vertical-rl;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: .18em;
}

.rail-nav__link::before {
  content: "";
  position: absolute;
  left: -8px;
  top: 50%;
  width: 2px;
  height: 22px;
  border-radius: 2px;
  background: var(--grad-cyan-violet);
  translate: 0 -50%;
  scale: 1 0;
  transition: scale var(--dur) var(--ease), opacity var(--dur) var(--ease);
}

.rail-nav__link:hover { color: var(--paper); }
.rail-nav__link:hover::before { scale: 1 1; }

.rail-nav__link[aria-current="page"] { color: var(--paper); }
.rail-nav__link[aria-current="page"]::before { scale: 1 1; }
.rail-nav__link[aria-current="page"] .rail-nav__num { color: var(--cyan); opacity: 1; }

.rail-status {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  width: 100%;
  padding-top: 14px;
  border-top: 1px solid rgba(141, 150, 178, .18);
}

.rail-status__dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--cyan);
  animation: rail-pulse 2.4s var(--ease) infinite;
}

.rail-status__text {
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .22em;
  color: var(--mute);
}

@keyframes rail-pulse {
  0% { box-shadow: 0 0 0 0 rgba(47, 224, 200, .5); }
  70% { box-shadow: 0 0 0 8px rgba(47, 224, 200, 0); }
  100% { box-shadow: 0 0 0 0 rgba(47, 224, 200, 0); }
}

/* ==========================================================================
   页脚
   ========================================================================== */

.site-footer {
  position: relative;
  margin-top: clamp(64px, 9vw, 132px);
  padding-block: clamp(48px, 6vw, 88px) 32px;
  overflow: hidden;
  border-top: 1px solid rgba(141, 150, 178, .14);
  background: linear-gradient(180deg, rgba(20, 27, 51, 0) 0%, rgba(20, 27, 51, .72) 42%, rgba(11, 16, 32, 1) 100%);
}

.footer-deco {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(60% 140px at 14% 0%, rgba(122, 92, 255, .20), transparent 72%),
    radial-gradient(48% 120px at 82% 0%, rgba(47, 224, 200, .14), transparent 72%),
    repeating-linear-gradient(90deg, rgba(47, 224, 200, .05) 0 1px, transparent 1px 68px);
}

.footer__inner { position: relative; z-index: 1; }

.footer__grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1.25fr;
  gap: clamp(28px, 3vw, 52px);
}

.footer__col { display: flex; flex-direction: column; gap: 14px; }

.footer__brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
}

.footer__mark { width: 36px; height: 36px; font-size: 17px; }

.footer__word {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 900;
  letter-spacing: .1em;
}

.footer__tagline {
  max-width: 22ch;
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--mute);
}

.footer__record {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: rgba(141, 150, 178, .72);
}

.footer__title {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .18em;
  color: var(--cyan);
}

.footer__list {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.footer__list--contact { gap: 8px; }

.footer__link {
  display: inline-block;
  padding-block: 4px;
  font-size: 15px;
  color: var(--mute);
  transition: color var(--dur) var(--ease), translate var(--dur) var(--ease);
}

.footer__link:hover { color: var(--paper); translate: 4px 0; }

.footer__contact-item {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  line-height: 1.8;
  color: var(--mute);
}

.footer__rule {
  height: 1px;
  margin-block: clamp(32px, 4vw, 48px) 22px;
  background: var(--grad-edge);
}

.footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.footer__legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 22px;
}

.footer__legal-link {
  font-size: 14px;
  color: var(--mute);
  transition: color var(--dur) var(--ease);
}

.footer__legal-link:hover { color: var(--cyan); }

.footer__copy {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: rgba(141, 150, 178, .72);
}

/* ==========================================================================
   滚动显现（CSS 滚动驱动动画，渐进增强）
   ========================================================================== */

@supports (animation-timeline: view()) {
  @media (prefers-reduced-motion: no-preference) {
    [data-reveal] {
      animation: reveal-rise linear both;
      animation-timeline: view();
      animation-range: entry 6% entry 58%;
    }
  }
}

@keyframes reveal-rise {
  from { opacity: 0; translate: 0 12px; }
  to { opacity: 1; translate: 0 0; }
}

/* ==========================================================================
   响应式
   ========================================================================== */

/* 平板横向：轨道收窄 */
@media (max-width: 1279px) and (min-width: 1024px) {
  :root { --rail-w: 64px; }

  .rail-brand__word { font-size: 13px; letter-spacing: .18em; }
  .rail-nav__text { font-size: 12px; letter-spacing: .14em; }
  .rail-nav__link { padding: 8px 4px; }
  .rail-status__text { font-size: 9px; letter-spacing: .18em; }
}

/* 平板竖向 / 手机：顶部条 + 抽屉 */
@media (max-width: 1023px) {
  body {
    padding-left: 0;
    padding-top: var(--topbar-h);
  }

  #main-content { scroll-margin-top: calc(var(--topbar-h) + 16px); }

  .scroll-progress { left: 0; }

  .topbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 80;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: var(--topbar-h);
    padding-inline: 18px;
    border-bottom: 1px solid rgba(141, 150, 178, .16);
    background: rgba(11, 16, 32, .88);
    backdrop-filter: blur(14px);
  }

  .nav-scrim {
    position: fixed;
    inset: 0;
    z-index: 74;
    display: block;
    border: 0;
    background: rgba(5, 8, 18, .66);
    backdrop-filter: blur(3px);
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--dur) var(--ease);
  }

  .site-header[data-open] .nav-scrim {
    opacity: 1;
    pointer-events: auto;
  }

  .nav-shell {
    top: 0;
    bottom: 0;
    width: min(84vw, 360px);
    z-index: 78;
    transform: translateX(-102%);
    visibility: hidden;
    pointer-events: none;
    border-right: 1px solid rgba(122, 92, 255, .35);
    box-shadow: 18px 0 60px rgba(0, 0, 0, .55);
    transition: transform var(--dur) var(--ease), visibility 0s linear var(--dur);
  }

  .site-header[data-open] .nav-shell {
    transform: translateX(0);
    visibility: visible;
    pointer-events: auto;
    transition: transform var(--dur) var(--ease), visibility 0s;
  }

  .nav-shell__inner {
    align-items: flex-start;
    gap: 22px;
    padding: 24px 20px 28px;
  }

  .rail-brand {
    flex-direction: row;
    align-items: center;
    gap: 12px;
    padding-bottom: 18px;
  }

  .rail-brand__word {
    writing-mode: horizontal-tb;
    font-size: 18px;
    letter-spacing: .1em;
  }

  .rail-nav {
    flex: none;
    justify-content: flex-start;
    width: 100%;
  }

  .rail-nav__list {
    align-items: stretch;
    gap: 4px;
    width: 100%;
  }

  .rail-nav__item { display: block; }

  .rail-nav__link {
    flex-direction: row;
    align-items: center;
    justify-content: flex-start;
    gap: 14px;
    width: 100%;
    padding: 13px 14px;
    border-radius: var(--radius-sm);
  }

  .rail-nav__text {
    writing-mode: horizontal-tb;
    font-size: 16px;
    letter-spacing: .04em;
  }

  .rail-nav__num { font-size: 11px; }

  .rail-nav__link::before {
    left: 0;
    top: 0;
    bottom: 0;
    width: 3px;
    height: auto;
    translate: 0;
    scale: 1 1;
    opacity: 0;
    border-radius: 0 3px 3px 0;
    transition: opacity var(--dur) var(--ease);
  }

  .rail-nav__link:hover::before,
  .rail-nav__link[aria-current="page"]::before { opacity: 1; scale: 1 1; }

  .rail-nav__link[aria-current="page"] { background: rgba(122, 92, 255, .14); }

  .rail-status {
    flex-direction: row;
    align-items: center;
    gap: 10px;
    margin-top: auto;
    padding-top: 18px;
  }

  .rail-status__text {
    writing-mode: horizontal-tb;
    font-size: 11px;
    letter-spacing: .16em;
  }

  .footer__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }

  .grid--2,
  .grid--3 { grid-template-columns: 1fr; }

  .grid--stagger > *:nth-child(even) { translate: none; }
}

@media (max-width: 640px) {
  .topbar__meta { display: none; }

  .footer__grid { grid-template-columns: 1fr; gap: 32px; }

  .footer__bottom { flex-direction: column; align-items: flex-start; }

  .footer__legal { gap: 18px; }

  .btn { width: 100%; justify-content: center; }
}

@media (max-width: 380px) {
  .nav-toggle__label { display: none; }
}

/* ==========================================================================
   降低动效偏好
   ========================================================================== */

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }

  .rail-status__dot { animation: none; box-shadow: 0 0 8px rgba(47, 224, 200, .8); }

  [data-reveal] { opacity: 1 !important; translate: none !important; }

  .card:hover,
  .btn:hover,
  .footer__link:hover { transform: none; translate: none; }
}