/* ============================================================
   GOGO赛势 · /assets/site.css
   共享外壳：reset / 变量 / 中文排版 / 头部 / 页脚 / 通用组件
   ============================================================ */

/* ---------- 1. reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body,
h1, h2, h3, h4, h5, h6,
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%; }

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

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

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

/* ---------- 2. 设计变量 ---------- */
:root {
  --arena: #0B1B33;
  --arena-2: #12294A;
  --arena-3: #17395f;
  --paper: #F4EBD9;
  --paper-2: #EADFC8;
  --ink: #241C17;
  --haze: #9FB3C8;
  --lime: #B6FF3B;
  --orange: #FF6A2A;
  --violet: #8B5CF6;
  --green: #2ED47A;
  --warn: #FFC247;

  --line: rgba(159, 179, 200, 0.18);
  --line-strong: rgba(159, 179, 200, 0.34);
  --line-ink: rgba(36, 28, 23, 0.18);

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

  --radius-pill: 999px;
  --radius-s: 4px;
  --radius-m: 10px;

  --shell-max: 1320px;
  --shell: clamp(24px, 6vw, 96px);

  --shadow-lift: 0 22px 60px -28px rgba(0, 0, 0, 0.78);
}

/* ---------- 3. 基础排版 ---------- */
body {
  min-height: 100vh;
  background: var(--arena);
  color: var(--paper);
  font-family: var(--font-body);
  font-size: clamp(15px, 0.55vw + 13px, 17px);
  line-height: 1.75;
  letter-spacing: 0.01em;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.01em;
}

#main-content { display: block; scroll-margin-top: 128px; }

/* ---------- 4. 头部 ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 90;
  padding: clamp(10px, 1.4vw, 18px) clamp(12px, 2.4vw, 28px) clamp(12px, 1.6vw, 20px);
  pointer-events: none;
  background: linear-gradient(180deg, rgba(11, 27, 51, 0.95) 0%, rgba(11, 27, 51, 0.68) 58%, rgba(11, 27, 51, 0) 100%);
  transition: padding 0.28s ease, background 0.28s ease;
}

.site-header[data-shrink="true"] {
  padding-top: 6px;
  padding-bottom: 10px;
  background: linear-gradient(180deg, rgba(11, 27, 51, 0.98) 0%, rgba(11, 27, 51, 0.8) 70%, rgba(11, 27, 51, 0) 100%);
}

.header-track {
  position: relative;
  max-width: 1360px;
  margin-inline: auto;
  display: flex;
  align-items: center;
  gap: clamp(8px, 1.2vw, 16px);
  pointer-events: auto;
}

/* 品牌岛 */
.brand-island {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 7px 18px 7px 7px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--line-strong);
  background: linear-gradient(135deg, rgba(23, 57, 95, 0.98), rgba(11, 27, 51, 0.98));
  box-shadow: var(--shadow-lift);
  transition: border-color 0.25s ease;
}

.brand-island:hover { border-color: rgba(182, 255, 59, 0.55); }

.brand-mark {
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  border-radius: 12px;
  background: var(--lime);
  color: var(--arena);
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 800;
  letter-spacing: -0.06em;
  transform: skewX(-6deg);
  transition: transform 0.25s ease, width 0.25s ease, height 0.25s ease, font-size 0.25s ease;
}

.brand-island:hover .brand-mark { transform: skewX(-9deg) translateY(-1px); }

.site-header[data-shrink="true"] .brand-mark {
  width: 32px;
  height: 32px;
  border-radius: 9px;
  font-size: 12px;
}

.brand-lockup {
  display: flex;
  flex-direction: column;
  gap: 1px;
  line-height: 1.15;
}

.brand-name {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(15px, 0.5vw + 13px, 17px);
  letter-spacing: 0.02em;
  color: var(--paper);
}

.brand-tag {
  font-size: 10.5px;
  letter-spacing: 0.14em;
  color: var(--haze);
}

.site-header[data-shrink="true"] .brand-tag { display: none; }

/* 导航岛 */
.nav-island {
  margin-left: auto;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 6px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--line-strong);
  background: rgba(18, 41, 74, 0.86);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  box-shadow: var(--shadow-lift);
  pointer-events: auto;
}

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

.nav-list a {
  display: inline-block;
  padding: 9px 14px;
  border-radius: var(--radius-pill);
  font-size: 13.5px;
  font-weight: 500;
  white-space: nowrap;
  color: rgba(244, 235, 217, 0.78);
  transition: background 0.2s ease, color 0.2s ease, box-shadow 0.2s ease;
}

.nav-list a:hover {
  background: rgba(159, 179, 200, 0.14);
  color: var(--paper);
}

.nav-list a[aria-current="page"] {
  background: rgba(182, 255, 59, 0.14);
  color: var(--lime);
  font-weight: 700;
  box-shadow: inset 0 0 0 1px rgba(182, 255, 59, 0.42);
}

.nav-tools {
  display: flex;
  align-items: center;
  gap: 10px;
  padding-left: 10px;
  margin-left: 4px;
  border-left: 1px solid var(--line);
}

.nav-announce {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.12em;
  color: var(--orange);
  white-space: nowrap;
}

.nav-cta {
  display: inline-block;
  padding: 9px 16px;
  border-radius: var(--radius-pill);
  background: var(--lime);
  color: var(--arena);
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 800;
  white-space: nowrap;
  transition: background 0.2s ease, transform 0.2s ease;
}

.nav-cta:hover {
  background: #caff6a;
  transform: translateY(-1px);
}

/* 汉堡按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  margin-left: auto;
  border-radius: 50%;
  border: 1px solid var(--line-strong);
  background: rgba(18, 41, 74, 0.92);
  color: var(--paper);
  pointer-events: auto;
}

.nav-toggle-bars {
  display: flex;
  flex-direction: column;
  gap: 4px;
  width: 18px;
}

.nav-toggle-bars span {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform 0.25s ease, opacity 0.2s ease;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* 滚动进度 */
.scroll-meter {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 3px;
  background: rgba(159, 179, 200, 0.14);
  pointer-events: none;
  overflow: hidden;
}

.scroll-meter-fill {
  display: block;
  height: 100%;
  width: 100%;
  transform: scaleX(0);
  transform-origin: left center;
  background: linear-gradient(90deg, var(--lime) 0%, var(--orange) 58%, var(--violet) 100%);
  transition: transform 0.08s linear;
}

/* 跳过链接 */
.skip-link {
  position: absolute;
  top: 8px;
  left: 50%;
  z-index: 200;
  padding: 10px 18px;
  border-radius: var(--radius-pill);
  background: var(--lime);
  color: var(--arena);
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 800;
  transform: translate(-50%, -180%);
  transition: transform 0.2s ease;
  pointer-events: auto;
}

.skip-link:focus { transform: translate(-50%, 0); }

/* ---------- 5. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(56px, 8vw, 120px);
  padding: clamp(40px, 5vw, 72px) 0 clamp(24px, 3vw, 36px);
  overflow: hidden;
  color: var(--paper);
  border-top: 1px solid var(--line);
  background:
    radial-gradient(120% 110% at 6% -20%, rgba(139, 92, 246, 0.28), transparent 58%),
    radial-gradient(90% 90% at 96% -10%, rgba(182, 255, 59, 0.12), transparent 52%),
    linear-gradient(180deg, #0E2240 0%, #081426 100%);
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(159, 179, 200, 0.07) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(159, 179, 200, 0.07) 1px, transparent 1px);
  background-size: 56px 56px;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.95), transparent 80%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.95), transparent 80%);
}

.footer-grid {
  position: relative;
  z-index: 1;
  width: min(var(--shell-max), 100% - var(--shell));
  margin-inline: auto;
  display: grid;
  grid-template-columns: minmax(230px, 1.55fr) minmax(130px, 0.7fr) minmax(130px, 0.7fr) minmax(230px, 1.15fr);
  gap: clamp(24px, 3.4vw, 56px);
}

.footer-brand { min-width: 0; }

.footer-mark {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 900;
  letter-spacing: 0.02em;
}

.footer-mark::before {
  content: "GO";
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 9px;
  background: var(--lime);
  color: var(--arena);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: -0.06em;
  transform: skewX(-6deg);
}

.footer-summary {
  margin-top: 16px;
  max-width: 34ch;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(244, 235, 217, 0.72);
}

.footer-note {
  margin-top: 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--orange);
}

.footer-col { min-width: 0; }

.footer-title {
  margin-bottom: 16px;
  font-family: var(--font-serif);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.18em;
  color: var(--haze);
}

.footer-title::after {
  content: "";
  display: block;
  width: 26px;
  height: 2px;
  margin-top: 10px;
  background: var(--orange);
}

.footer-links li + li { margin-top: 10px; }

.footer-links a {
  display: inline-block;
  font-size: 14px;
  color: rgba(244, 235, 217, 0.8);
  border-bottom: 1px solid transparent;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.footer-links a:hover {
  color: var(--lime);
  border-bottom-color: rgba(182, 255, 59, 0.5);
}

.footer-contact li + li { margin-top: 14px; }

.footer-k {
  display: block;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.16em;
  color: var(--haze);
}

.footer-v {
  display: block;
  font-size: 13.5px;
  line-height: 1.6;
  color: rgba(244, 235, 217, 0.88);
  word-break: break-word;
}

.footer-base {
  position: relative;
  z-index: 1;
  width: min(var(--shell-max), 100% - var(--shell));
  margin: clamp(30px, 4vw, 52px) auto 0;
  padding-top: 20px;
  border-top: 1px solid var(--line);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 24px;
  font-size: 12.5px;
  color: rgba(244, 235, 217, 0.6);
}

.footer-copyright,
.footer-icp {
  font-family: var(--font-mono);
  letter-spacing: 0.06em;
}

/* ---------- 6. 通用布局组件 ---------- */
.wrap {
  width: min(var(--shell-max), 100% - var(--shell));
  margin-inline: auto;
}

.section { padding-block: clamp(40px, 6vw, 88px); }

.section--paper {
  background-color: var(--paper);
  background-image:
    linear-gradient(to right, rgba(36, 28, 23, 0.045) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(36, 28, 23, 0.045) 1px, transparent 1px);
  background-size: 72px 72px;
  color: var(--ink);
}

.rule {
  height: 1px;
  border: 0;
  margin: 0;
  background: var(--line);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--lime);
}

.eyebrow::before {
  content: "";
  display: block;
  width: 22px;
  height: 2px;
  background: currentColor;
}

.section--paper .eyebrow { color: var(--orange); }

.section-title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(26px, 3.2vw, 38px);
  line-height: 1.15;
  letter-spacing: -0.015em;
}

.tilt {
  transform: skewX(-5deg);
  transform-origin: left center;
  display: inline-block;
}

.lead {
  font-family: var(--font-serif);
  font-size: clamp(17px, 0.9vw + 14px, 21px);
  line-height: 1.8;
  color: rgba(244, 235, 217, 0.9);
}

.section--paper .lead { color: rgba(36, 28, 23, 0.82); }

.prose {
  max-width: 38em;
  font-size: clamp(15px, 0.55vw + 13px, 17px);
  line-height: 1.85;
  color: rgba(244, 235, 217, 0.86);
}

.prose p + p { margin-top: 1.1em; }

.prose h2,
.prose h3 {
  margin-top: 1.8em;
  margin-bottom: 0.6em;
  font-family: var(--font-serif);
  font-weight: 700;
  line-height: 1.35;
  color: var(--paper);
}

.prose--paper { color: rgba(36, 28, 23, 0.86); }

.prose--paper h2,
.prose--paper h3 { color: var(--ink); }

.prose a {
  color: inherit;
  border-bottom: 1px solid currentColor;
}

.mono {
  font-family: var(--font-mono);
  letter-spacing: 0.04em;
}

.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
}

/* ---------- 7. 网格与卡片 ---------- */
.grid {
  display: grid;
  gap: clamp(16px, 2.4vw, 32px);
}

.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

.card {
  position: relative;
  padding: clamp(18px, 2.2vw, 28px);
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: rgba(18, 41, 74, 0.72);
  transition: border-color 0.25s ease, transform 0.25s ease, background 0.25s ease;
}

.card:hover {
  border-color: rgba(182, 255, 59, 0.4);
  background: rgba(23, 57, 95, 0.82);
  transform: translateY(-3px);
}

.card--paper {
  background: var(--paper);
  color: var(--ink);
  border-color: var(--line-ink);
}

.card--paper:hover {
  background: var(--paper-2);
  border-color: rgba(255, 106, 42, 0.5);
}

/* ---------- 8. 按钮与标签 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 22px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 800;
  line-height: 1;
  letter-spacing: 0.02em;
  transition: transform 0.2s ease, background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn--lime {
  background: var(--lime);
  color: var(--arena);
}

.btn--lime:hover { background: #caff6a; }

.btn--ghost {
  background: transparent;
  color: var(--paper);
  border-color: var(--line-strong);
}

.btn--ghost:hover {
  border-color: var(--lime);
  color: var(--lime);
}

.btn--paper {
  background: var(--ink);
  color: var(--paper);
}

.btn--paper:hover { background: #3a2d24; }

.pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--haze);
  white-space: nowrap;
}

.pill--lime {
  color: var(--lime);
  border-color: rgba(182, 255, 59, 0.45);
  background: rgba(182, 255, 59, 0.08);
}

.pill--orange {
  color: var(--orange);
  border-color: rgba(255, 106, 42, 0.45);
  background: rgba(255, 106, 42, 0.08);
}

.pill--violet {
  color: #c4b1fb;
  border-color: rgba(139, 92, 246, 0.5);
  background: rgba(139, 92, 246, 0.14);
}

.pill--live {
  color: var(--green);
  border-color: rgba(46, 212, 122, 0.45);
  background: rgba(46, 212, 122, 0.1);
}

.pill--live::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: currentColor;
  animation: pill-pulse 1.9s ease-in-out infinite;
}

@keyframes pill-pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.35; transform: scale(0.72); }
}

/* ---------- 9. 面包屑 ---------- */
.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--haze);
}

.crumbs li {
  display: flex;
  align-items: center;
  gap: 6px;
}

.crumbs li + li::before {
  content: "›";
  color: rgba(159, 179, 200, 0.5);
}

.crumbs a { transition: color 0.2s ease; }
.crumbs a:hover { color: var(--lime); }

.section--paper .crumbs { color: rgba(36, 28, 23, 0.55); }
.section--paper .crumbs a:hover { color: var(--orange); }

/* ---------- 10. 图片容器 ---------- */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: linear-gradient(135deg, #12294A 0%, #0B1B33 58%, #1c1040 100%);
}

.media-frame::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    135deg,
    rgba(159, 179, 200, 0.1) 0 1px,
    transparent 1px 14px
  );
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(180deg, rgba(11, 27, 51, 0) 42%, rgba(11, 27, 51, 0.66) 100%);
}

.media-frame > img,
.media-frame > picture > img {
  position: relative;
  z-index: 1;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s ease;
}

.media-frame:hover > img,
.media-frame:hover > picture > img { transform: scale(1.04); }

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

.media-frame__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
  padding: 12px 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--paper);
}

/* ---------- 11. 工具类 ---------- */
.is-active {
  color: var(--lime) !important;
  background: rgba(182, 255, 59, 0.12);
}

.section--paper .is-active {
  color: var(--ink) !important;
  background: rgba(255, 106, 42, 0.16);
}

.visually-hidden {
  position: absolute !important;
  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;
}

/* ---------- 12. 响应式 ---------- */
@media (max-width: 1180px) {
  .nav-announce { display: none; }
  .nav-list a { padding: 9px 11px; font-size: 13px; }
}

@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: minmax(220px, 1.4fr) repeat(2, minmax(120px, 0.8fr));
  }
  .footer-col--contact { grid-column: 1 / -1; }
  .footer-contact {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px 24px;
  }
  .footer-contact li + li { margin-top: 0; }
}

@media (max-width: 859px) {
  .nav-toggle { display: inline-flex; }

  .nav-island {
    position: absolute;
    top: calc(100% + 10px);
    left: 0;
    right: 0;
    margin-left: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 12px;
    border-radius: 22px;
    background: rgba(11, 27, 51, 0.98);
    box-shadow: 0 26px 60px -18px rgba(0, 0, 0, 0.7);
  }

  .nav-island[data-open="true"] { display: flex; }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
  }

  .nav-list a {
    padding: 13px 14px;
    border-radius: 14px;
    font-size: 15px;
  }

  .nav-tools {
    flex-direction: column;
    align-items: stretch;
    gap: 8px;
    margin: 10px 0 0;
    padding: 12px 0 0;
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .nav-announce {
    display: block;
    text-align: center;
  }

  .nav-cta {
    padding: 13px;
    text-align: center;
  }

  .site-header[data-shrink="true"] .brand-tag { display: none; }

  .grid--3,
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 720px) {
  .footer-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
  }

  .footer-contact {
    grid-template-columns: minmax(0, 1fr);
    gap: 12px;
  }

  .footer-base {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }
}

@media (max-width: 620px) {
  .grid--2,
  .grid--3,
  .grid--4 { grid-template-columns: minmax(0, 1fr); }

  .brand-tag { display: none; }

  #main-content { scroll-margin-top: 96px; }
}

/* ---------- 13. 减少动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }

  .btn:hover,
  .card:hover,
  .nav-cta:hover { transform: none; }

  .media-frame:hover > img,
  .media-frame:hover > picture > img { transform: none; }
}