/* ============================================================
   奇异果赛场 · 共享样式 /assets/site.css
   纸奶白 + 籽墨黑 + 果肉绿 + 荧光果绿 + 暖橙日光
   ============================================================ */

/* ---------- 01 reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}

body,
h1, h2, h3, h4,
p, ul, ol, li, figure, blockquote, dl, dd {
  margin: 0;
}

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

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

a { color: inherit; }

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

table { border-collapse: collapse; }

[hidden] { display: none !important; }

/* ---------- 02 设计令牌 ---------- */
:root {
  /* 色彩 */
  --paper: #F4EEE2;
  --salt: #FCFBF7;
  --seed: #131310;
  --night: #1E1D17;
  --flesh: #7BC043;
  --neon: #C8FF57;
  --sun: #F0782D;
  --brown: #3A3128;
  --vein: #8A8C79;
  --mist: #DCEBC8;
  --cream: #E8E4D8;

  --hair: rgba(58, 49, 40, .16);
  --hair-strong: rgba(58, 49, 40, .32);
  --hair-dark: rgba(200, 255, 87, .18);

  /* 九级字阶 */
  --t-12: .75rem;
  --t-14: .875rem;
  --t-17: 1.0625rem;
  --t-21: 1.3125rem;
  --t-28: 1.75rem;
  --t-40: 2.5rem;
  --t-64: clamp(2.25rem, 4.6vw, 4rem);
  --t-96: clamp(2.75rem, 7vw, 6rem);
  --t-144: clamp(3.25rem, 10vw, 9rem);

  /* 字体 */
  --font-display: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --font-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", SimSun, serif;
  --font-mono: "JetBrains Mono", "Roboto Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  /* 形状与动效 */
  --ease: cubic-bezier(.22, 1, .36, 1);
  --radius-pill: 999px;
  --radius-card: 20px;
  --radius-soft: 26px;
  --shell: 1240px;
  --shadow-float: 0 12px 34px -24px rgba(19, 19, 16, .85);
}

/* ---------- 03 基础排版 ---------- */
body {
  background-color: var(--paper);
  background-image:
    radial-gradient(90% 60% at 8% -10%, rgba(220, 235, 200, .75), transparent 62%),
    radial-gradient(70% 50% at 108% 6%, rgba(240, 120, 45, .07), transparent 60%);
  background-repeat: no-repeat;
  color: var(--brown);
  font-family: var(--font-body);
  font-size: var(--t-17);
  font-weight: 400;
  line-height: 1.85;
  letter-spacing: .01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 900;
  line-height: 1.06;
  letter-spacing: -.02em;
  color: var(--brown);
  overflow-wrap: break-word;
  text-wrap: balance;
}

h1 { font-size: var(--t-64); }
h2 { font-size: var(--t-40); }
h3 { font-size: var(--t-28); }
h4 { font-size: var(--t-21); font-weight: 800; line-height: 1.3; }

p { overflow-wrap: break-word; }

strong, b { font-weight: 800; }

::selection {
  background: var(--flesh);
  color: var(--seed);
}

/* ---------- 04 无障碍 ---------- */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

:focus-visible {
  outline: 2px solid var(--flesh);
  outline-offset: 3px;
  border-radius: 4px;
}

.panel--dark :focus-visible,
.site-footer :focus-visible,
.skip-link:focus-visible {
  outline-color: var(--neon);
}

/* ---------- 05 布局骨架 ---------- */
.wrap {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: clamp(18px, 4vw, 40px);
}

.wrap--narrow { max-width: 880px; }

.section { padding-block: clamp(44px, 6vw, 84px); }
.section--loose { padding-block: clamp(64px, 9vw, 132px); }

.hairline {
  height: 1px;
  border: 0;
  margin-block: clamp(24px, 4vw, 52px);
  background: var(--hair);
}

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(16px, 2vw, 28px);
}

.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; }

/* ---------- 06 排版组件 ---------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: .7em;
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: var(--t-14);
  letter-spacing: .18em;
  color: var(--brown);
  margin-bottom: .9em;
}

.eyebrow::before {
  content: "";
  width: 26px;
  height: 2px;
  flex: none;
  background: var(--flesh);
  border-radius: 2px;
}

.section-head { max-width: 46ch; margin-bottom: clamp(24px, 4vw, 44px); }

.section-title {
  font-size: var(--t-64);
  font-weight: 900;
  letter-spacing: -.025em;
}

.lede {
  font-size: var(--t-21);
  line-height: 1.75;
  max-width: 30em;
  color: var(--brown);
}

.prose { max-width: 38em; }

.prose > * + * { margin-top: 1.15em; }

.prose p,
.prose li {
  max-width: 34em;
  line-height: 1.85;
}

.prose h2 { font-size: var(--t-40); margin-top: 1.6em; }
.prose h3 { font-size: var(--t-28); margin-top: 1.5em; }

.prose ul,
.prose ol {
  padding-left: 1.15em;
  list-style: disc;
}

.prose ol { list-style: decimal; }

.prose a {
  color: var(--brown);
  text-decoration: underline;
  text-decoration-color: var(--flesh);
  text-decoration-thickness: 2px;
  text-underline-offset: .22em;
}

.prose a:hover { background: var(--mist); }

.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: -.01em;
  margin-inline-end: .18em;
}

/* ---------- 07 按钮与标签 ---------- */
.btn {
  --btn-bg: var(--flesh);
  --btn-fg: var(--seed);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5em;
  padding: .8em 1.45em;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  background: var(--btn-bg);
  color: var(--btn-fg);
  font-family: var(--font-display);
  font-size: var(--t-14);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: .02em;
  text-decoration: none;
  cursor: pointer;
  transition: transform .18s var(--ease), box-shadow .18s var(--ease), background-color .18s var(--ease), color .18s var(--ease);
}

.btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 14px 26px -18px rgba(19, 19, 16, .8);
}

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

.btn--cta { --btn-bg: var(--sun); --btn-fg: var(--seed); }
.btn--solid { --btn-bg: var(--flesh); --btn-fg: var(--seed); }

.btn--ghost {
  --btn-bg: transparent;
  --btn-fg: var(--brown);
  border-color: var(--hair-strong);
}

.btn--ghost:hover { background: var(--mist); border-color: var(--flesh); }

.btn--sm {
  padding: .58em 1.1em;
  font-size: var(--t-12);
  letter-spacing: .04em;
}

.chip,
.tag {
  display: inline-flex;
  align-items: center;
  gap: .4em;
  padding: .28em .8em;
  border-radius: var(--radius-pill);
  border: 1px solid var(--hair);
  background: var(--salt);
  color: var(--brown);
  font-size: var(--t-12);
  font-weight: 700;
  letter-spacing: .06em;
  line-height: 1.7;
}

.tag {
  background: var(--mist);
  border-color: transparent;
}

.tag--sun {
  background: rgba(240, 120, 45, .16);
  color: #8a3d08;
}

.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: clamp(20px, 3vw, 32px);
}

.filter-btn {
  padding: .5em 1.05em;
  border-radius: var(--radius-pill);
  border: 1px solid var(--hair-strong);
  background: transparent;
  color: var(--brown);
  font-family: var(--font-display);
  font-size: var(--t-14);
  font-weight: 700;
  line-height: 1.4;
  cursor: pointer;
  transition: background-color .16s var(--ease), color .16s var(--ease), border-color .16s var(--ease);
}

.filter-btn:hover { background: var(--mist); }

.filter-btn[aria-pressed="true"] {
  background: var(--seed);
  border-color: var(--seed);
  color: var(--neon);
}

/* ---------- 08 面包屑 ---------- */
.crumbs {
  font-size: var(--t-12);
  letter-spacing: .06em;
  color: var(--vein);
  padding-block: clamp(16px, 2vw, 24px);
}

.crumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .55em;
}

.crumbs li + li::before {
  content: "/";
  margin-inline-end: .55em;
  color: var(--hair-strong);
}

.crumbs a {
  text-decoration: none;
  color: var(--vein);
  border-bottom: 1px solid transparent;
}

.crumbs a:hover { color: var(--brown); border-bottom-color: var(--flesh); }

.crumbs [aria-current="page"] { color: var(--brown); font-weight: 700; }

/* ---------- 09 面板 / 卡片 / 数据表 ---------- */
.panel {
  background: var(--salt);
  border: 1px solid var(--hair);
  border-radius: var(--radius-card);
  padding: clamp(18px, 2.6vw, 30px);
}

.panel--pad { padding: clamp(24px, 4vw, 48px); }

.panel--dark {
  background-color: var(--seed);
  background-image:
    radial-gradient(120% 90% at 88% -12%, rgba(123, 192, 67, .26), transparent 62%),
    radial-gradient(80% 60% at -10% 110%, rgba(240, 120, 45, .16), transparent 60%);
  border-color: rgba(200, 255, 87, .18);
  color: var(--cream);
  border-radius: var(--radius-card);
  padding: clamp(18px, 2.6vw, 30px);
}

.panel--dark h2,
.panel--dark h3,
.panel--dark h4 { color: var(--salt); }

.panel--dark .num { color: var(--neon); }
.panel--dark .eyebrow { color: var(--cream); }

.card {
  background: var(--salt);
  border: 1px solid var(--hair);
  border-radius: var(--radius-card);
  padding: clamp(16px, 2.2vw, 26px);
  transition: border-color .18s var(--ease), box-shadow .18s var(--ease), transform .18s var(--ease);
}

.card:hover {
  border-color: var(--flesh);
  box-shadow: 0 18px 34px -28px rgba(19, 19, 16, .9);
}

.data-table {
  width: 100%;
  font-size: var(--t-14);
  font-variant-numeric: tabular-nums;
}

.data-table th {
  padding: 10px 12px;
  text-align: left;
  font-size: var(--t-12);
  font-weight: 700;
  letter-spacing: .09em;
  color: var(--vein);
  border-bottom: 1px solid var(--hair);
  white-space: nowrap;
}

.data-table td {
  padding: 12px;
  border-bottom: 1px solid var(--hair);
  color: inherit;
  vertical-align: middle;
}

.data-table td.num,
.data-table th.num {
  font-family: var(--font-mono);
  text-align: right;
}

.data-table tbody tr { transition: background-color .16s var(--ease); }
.data-table tbody tr:hover { background: rgba(123, 192, 67, .14); }

.panel--dark .data-table th {
  color: rgba(232, 228, 216, .62);
  border-bottom-color: var(--hair-dark);
}

.panel--dark .data-table td { border-bottom-color: rgba(200, 255, 87, .1); }
.panel--dark .data-table tbody tr:hover { background: rgba(200, 255, 87, .08); }

/* ---------- 10 媒体容器（页面阶段放置图片） ---------- */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  isolation: isolate;
  border-radius: var(--radius-card);
  border: 1px solid rgba(19, 19, 16, .4);
  background-color: var(--night);
  background-image:
    repeating-linear-gradient(115deg, rgba(200, 255, 87, .07) 0 1px, transparent 1px 26px),
    radial-gradient(120% 100% at 20% 0%, rgba(123, 192, 67, .3), transparent 62%);
  color: var(--cream);
}

.media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media--square { aspect-ratio: 1 / 1; }
.media--portrait { aspect-ratio: 3 / 4; }
.media--wide { aspect-ratio: 16 / 9; }

.media--neon { box-shadow: inset 0 0 0 1px var(--neon); }

.media__ph {
  display: grid;
  place-items: center;
  width: 100%;
  height: 100%;
  min-height: 120px;
  padding: 18px;
  font-family: var(--font-mono);
  font-size: var(--t-12);
  letter-spacing: .12em;
  color: rgba(200, 255, 87, .78);
  text-align: center;
}

.media__tag {
  position: absolute;
  left: 14px;
  bottom: 14px;
  z-index: 2;
  padding: .26em .78em;
  border-radius: var(--radius-pill);
  background: var(--neon);
  color: var(--seed);
  font-family: var(--font-display);
  font-size: var(--t-12);
  font-weight: 800;
  letter-spacing: .05em;
}

/* ---------- 11 悬浮胶囊头部 ---------- */
.skip-link {
  position: fixed;
  top: 14px;
  left: 14px;
  z-index: 300;
  padding: .7em 1.3em;
  border-radius: var(--radius-pill);
  background: var(--seed);
  color: var(--neon);
  font-family: var(--font-display);
  font-size: var(--t-14);
  font-weight: 800;
  text-decoration: none;
  transform: translateY(-160%);
  transition: transform .2s var(--ease);
}

.skip-link:focus {
  transform: translateY(0);
  outline: 2px solid var(--neon);
  outline-offset: 3px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 90;
  padding: 20px clamp(14px, 3vw, 28px) 0;
  transition: padding-top .22s var(--ease);
}

.site-header[data-scrolled] { padding-top: 8px; }

.masthead {
  position: relative;
  display: flex;
  align-items: center;
  gap: clamp(10px, 1.8vw, 26px);
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding: 10px 10px 10px 18px;
  border-radius: var(--radius-soft);
  border: 1px solid var(--hair);
  background: rgba(252, 251, 247, .88);
  box-shadow: var(--shadow-float);
  backdrop-filter: blur(12px) saturate(1.1);
  -webkit-backdrop-filter: blur(12px) saturate(1.1);
  transition: padding .22s var(--ease), box-shadow .22s var(--ease), border-radius .22s var(--ease);
}

.site-header[data-scrolled] .masthead {
  padding: 6px 8px 6px 14px;
  border-radius: 18px;
  box-shadow: 0 16px 36px -26px rgba(19, 19, 16, .95);
}

/* 品牌：纯 CSS 奇异果切面 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: .7em;
  flex: none;
  text-decoration: none;
  color: var(--brown);
}

.brand__mark {
  position: relative;
  display: block;
  flex: none;
  width: 1em;
  height: 1em;
  font-size: 38px;
  border-radius: 50%;
  background-image:
    radial-gradient(circle at 50% 50%, #F0F8DC 0 9%, transparent 10%),
    radial-gradient(circle at 50% 50%, var(--flesh) 0 56%, #68A336 57% 74%, var(--brown) 75% 100%);
  box-shadow: inset 0 0 0 1px rgba(19, 19, 16, .28);
  transition: font-size .22s var(--ease);
}

.brand__mark::before {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: .085em;
  height: .085em;
  border-radius: 50%;
  background: var(--seed);
  transform: translate(-50%, -50%);
  box-shadow:
    0 -.3em 0 0 var(--seed),
    0 .3em 0 0 var(--seed),
    -.3em 0 0 0 var(--seed),
    .3em 0 0 0 var(--seed),
    .21em .21em 0 0 var(--seed),
    -.21em .21em 0 0 var(--seed),
    .21em -.21em 0 0 var(--seed),
    -.21em -.21em 0 0 var(--seed);
}

.brand__mark--lg { font-size: 56px; }

.site-header[data-scrolled] .brand__mark { font-size: 30px; }

.brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1.25;
}

.brand__name {
  font-family: var(--font-display);
  font-size: var(--t-17);
  font-weight: 900;
  letter-spacing: -.015em;
  color: var(--seed);
}

.brand__sub {
  font-size: var(--t-12);
  letter-spacing: .12em;
  color: var(--vein);
}

/* 导航 */
.primary-nav { margin-inline: auto; }

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.nav-list a {
  display: block;
  padding: 9px 14px;
  border-radius: var(--radius-pill);
  font-family: var(--font-display);
  font-size: var(--t-14);
  font-weight: 700;
  letter-spacing: .01em;
  line-height: 1.4;
  color: var(--brown);
  text-decoration: none;
  white-space: nowrap;
  transition: background-color .16s var(--ease), color .16s var(--ease);
}

.nav-list a:hover { background: var(--mist); color: var(--seed); }

.nav-list a[aria-current="page"] {
  background: var(--seed);
  color: var(--neon);
}

/* 右侧入口 */
.masthead__side {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-left: auto;
  flex: none;
}

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

.utility__link {
  font-size: var(--t-12);
  font-weight: 700;
  letter-spacing: .04em;
  color: var(--vein);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  padding-bottom: 1px;
  transition: color .16s var(--ease), border-color .16s var(--ease);
}

.utility__link:hover {
  color: var(--brown);
  border-bottom-color: var(--sun);
}

/* 移动开关 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--hair-strong);
  background: var(--salt);
  color: var(--brown);
  font-family: var(--font-display);
  font-size: var(--t-12);
  font-weight: 800;
  letter-spacing: .08em;
  cursor: pointer;
  transition: background-color .18s var(--ease), color .18s var(--ease), border-color .18s var(--ease);
}

.nav-toggle__bars {
  display: grid;
  gap: 4px;
  width: 16px;
}

.nav-toggle__bars span {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: var(--seed);
  transition: transform .18s var(--ease), background-color .18s var(--ease);
}

.site-header[data-open] .nav-toggle {
  background: var(--seed);
  border-color: var(--seed);
  color: var(--neon);
}

.site-header[data-open] .nav-toggle__bars span { background: var(--neon); }
.site-header[data-open] .nav-toggle__bars span:first-child { transform: translateY(3px) rotate(45deg); }
.site-header[data-open] .nav-toggle__bars span:last-child { transform: translateY(-3px) rotate(-45deg); }

/* ---------- 12 深色页脚 ---------- */
.site-footer {
  position: relative;
  overflow: hidden;
  margin-top: clamp(64px, 9vw, 140px);
  background-color: var(--seed);
  background-image:
    radial-gradient(60% 70% at 4% 0%, rgba(123, 192, 67, .24), transparent 64%),
    radial-gradient(50% 60% at 100% 100%, rgba(240, 120, 45, .14), transparent 62%);
  color: var(--cream);
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(200, 255, 87, .45), transparent);
  pointer-events: none;
}

.footer__inner {
  display: grid;
  grid-template-columns: 1.1fr 1.9fr;
  gap: clamp(32px, 5vw, 72px);
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding: clamp(48px, 7vw, 92px) clamp(18px, 4vw, 40px) clamp(28px, 4vw, 44px);
}

.footer__brand .brand__mark {
  margin-bottom: 18px;
  box-shadow: inset 0 0 0 1px rgba(200, 255, 87, .35);
}

.footer__name {
  font-family: var(--font-display);
  font-size: var(--t-28);
  font-weight: 900;
  letter-spacing: -.02em;
  line-height: 1.15;
  color: var(--salt);
}

.footer__tag {
  margin-top: 6px;
  font-size: var(--t-14);
  letter-spacing: .14em;
  color: rgba(200, 255, 87, .8);
}

.footer__note {
  margin-top: 16px;
  max-width: 26em;
  font-size: var(--t-14);
  line-height: 1.8;
  color: rgba(232, 228, 216, .68);
}

.footer__cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(18px, 3vw, 36px);
}

.footer__col-title {
  font-family: var(--font-serif);
  font-size: var(--t-14);
  font-weight: 500;
  letter-spacing: .18em;
  color: var(--salt);
  padding-bottom: 10px;
  margin-bottom: 12px;
  border-bottom: 1px solid var(--hair-dark);
}

.footer__links {
  display: grid;
  gap: 8px;
  font-size: var(--t-14);
}

.footer__links a {
  color: rgba(232, 228, 216, .76);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .16s var(--ease), border-color .16s var(--ease);
}

.footer__links a:hover,
.footer__links a:focus-visible {
  color: var(--neon);
  border-bottom-color: var(--neon);
}

.footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 28px;
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding: 20px clamp(18px, 4vw, 40px) clamp(28px, 4vw, 40px);
  border-top: 1px solid rgba(200, 255, 87, .14);
  font-family: var(--font-mono);
  font-size: var(--t-12);
  letter-spacing: .02em;
  color: rgba(232, 228, 216, .56);
}

.footer__legal { color: rgba(232, 228, 216, .72); }
.footer__contact { color: rgba(232, 228, 216, .56); }

.footer__mini {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
}

.footer__mini a {
  color: rgba(232, 228, 216, .62);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.footer__mini a:hover {
  color: var(--neon);
  border-bottom-color: var(--neon);
}

/* ---------- 13 显现协议 ---------- */
html.js [data-reveal] {
  opacity: 0;
  transform: translateY(8px);
  transition: opacity .24s var(--ease), transform .24s var(--ease);
}

html.js [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 14 平板 ---------- */
@media (max-width: 1080px) {
  .brand__sub { display: none; }
  .nav-list a { padding: 8px 11px; }
  .footer__inner { grid-template-columns: 1fr; }
}

@media (max-width: 960px) {
  .site-header { padding-top: 14px; }

  .nav-toggle {
    display: inline-flex;
    margin-left: auto;
  }

  .masthead { padding: 8px 10px 8px 14px; }

  .primary-nav {
    position: absolute;
    top: calc(100% + 12px);
    left: 0;
    right: 0;
    margin-inline: 0;
    display: none;
    padding: 10px;
    border-radius: var(--radius-card);
    border: 1px solid var(--hair);
    background: var(--salt);
    box-shadow: 0 30px 60px -38px rgba(19, 19, 16, .95);
    z-index: 95;
  }

  .site-header[data-open] .primary-nav { display: block; }

  .nav-list {
    display: grid;
    gap: 2px;
  }

  .nav-list a {
    padding: 12px 16px;
    border-radius: 14px;
    font-size: var(--t-17);
  }

  .masthead__side {
    margin-left: 0;
    gap: 10px;
  }

  .utility { display: none; }

  .col-4, .col-5, .col-6, .col-7, .col-8 { grid-column: span 6; }

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

/* ---------- 15 手机 ---------- */
@media (max-width: 640px) {
  body { font-size: var(--t-17); line-height: 1.8; }

  .grid-12 { gap: 14px; }

  .col-4, .col-5, .col-6, .col-7, .col-8, .col-12 { grid-column: 1 / -1; }

  .section-title { font-size: var(--t-40); }

  .lede { font-size: var(--t-17); }

  .footer__cols { grid-template-columns: 1fr 1fr; gap: 24px; }

  .footer__bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
    font-size: var(--t-12);
  }

  .btn--sm { padding: .55em .95em; }
}

@media (max-width: 480px) {
  .masthead__side { display: none; }
  .brand__name { font-size: var(--t-14); }
  .brand__mark { font-size: 32px; }
  .site-header[data-scrolled] .brand__mark { font-size: 28px; }
  .footer__cols { grid-template-columns: 1fr; }
}

/* ---------- 16 降低动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }

  html { scroll-behavior: auto; }

  html.js [data-reveal] {
    opacity: 1;
    transform: none;
  }

  .btn:hover { transform: none; }
  .skip-link { transition: none; }
}