/* ============================================================
   凯时平台中心 · /assets/site.css
   共享层：reset / 变量 / 中文排版 / 页头 / 页脚 / 基础组件
   ============================================================ */

/* ---------- 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, figcaption, dl, dd, dt, blockquote {
  margin: 0;
}

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

body {
  min-height: 100vh;
  background-color: var(--ink-900);
  color: var(--ice-50);
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 400;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

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

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

input, textarea, select { font: inherit; }

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-head);
  font-weight: 800;
  letter-spacing: -0.035em;
  line-height: 1.2;
}

strong, b { font-weight: 700; }

::selection {
  background-color: var(--cyan-500);
  color: var(--ink-900);
}

/* ---------- 变量 ---------- */
:root {
  --ink-900: #071426;
  --ink-800: #0B1E36;
  --ink-700: #102A4A;
  --cyan-500: #22D3EE;
  --cyan-300: #7DE8F7;
  --ice-50: #EAF6FF;
  --slate-300: #A9BDD3;
  --orange-500: #FF8A3D;
  --orange-300: #FFB27A;
  --line-400: #244366;
  --mint-500: #2DD4BF;
  --void: #030A14;

  --font-head: "HarmonyOS Sans SC", "Source Han Sans SC", "Noto Sans SC", sans-serif;
  --font-body: "Source Han Sans SC", "Noto Sans SC", system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, monospace;

  --shadow-brut: 6px 6px 0 0 var(--void);
  --shadow-lift: 9px 11px 0 0 var(--void);
  --shadow-soft: 0 18px 36px -24px rgba(0, 0, 0, 0.92);

  --dur: 180ms;
  --ease: cubic-bezier(0.22, 0.7, 0.3, 1);

  --wrap: 1240px;
  --pad: clamp(16px, 4vw, 40px);
  --header-h: 0px;
}

/* ---------- 通用容器与排版 ---------- */
.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--pad);
}

.mono {
  font-family: var(--font-mono);
  font-weight: 500;
  letter-spacing: 0.02em;
  font-variant-numeric: tabular-nums;
}

.muted { color: var(--slate-300); }

.prose {
  max-width: 68ch;
  color: var(--slate-300);
  font-size: 16.5px;
  line-height: 1.85;
}

.prose p + p { margin-top: 1em; }
.prose a {
  color: var(--cyan-300);
  border-bottom: 1px solid rgba(34, 211, 238, 0.45);
}
.prose a:hover { color: var(--cyan-500); border-bottom-color: var(--cyan-500); }

.section { padding-block: clamp(44px, 6vw, 88px); }

.section-head {
  display: grid;
  gap: 10px;
  padding-top: 18px;
  border-top: 2px solid var(--line-400);
  margin-bottom: clamp(22px, 3vw, 34px);
}

.section-head__index {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.2em;
  color: var(--cyan-500);
}

.section-head__title {
  font-size: clamp(22px, 3.2vw, 32px);
  color: var(--ice-50);
}

.section-head__note {
  max-width: 62ch;
  color: var(--slate-300);
  font-size: 15px;
}

/* ---------- 焦点 ---------- */
:focus-visible {
  outline: 2px solid var(--cyan-500);
  outline-offset: 2px;
}

/* ---------- 跳过链接 ---------- */
.skip-link {
  position: absolute;
  top: -100px;
  left: 12px;
  z-index: 120;
  display: inline-block;
  padding: 10px 18px;
  background-color: var(--orange-500);
  color: var(--ink-900);
  font-weight: 700;
  font-size: 14px;
  border: 2px solid var(--ink-900);
  box-shadow: var(--shadow-brut);
  transition: top var(--dur) var(--ease);
}

.skip-link:focus,
.skip-link:focus-visible {
  top: 10px;
}

/* ============================================================
   页头
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background-image: linear-gradient(180deg, #05101F 0%, var(--ink-900) 100%);
  border-bottom: 2px solid var(--line-400);
}

/* 阅读进度条 */
.progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 3px;
  background-color: rgba(36, 67, 102, 0.55);
  overflow: hidden;
}

.progress__bar {
  display: block;
  width: 0;
  height: 100%;
  background-image: linear-gradient(90deg, var(--cyan-500) 0%, var(--cyan-300) 62%, var(--orange-500) 100%);
  transition: width 120ms linear;
}

/* 上层：品牌铭牌 */
.header__strip {
  border-bottom: 1px solid rgba(36, 67, 102, 0.8);
  background-image: radial-gradient(120% 180% at 8% 0%, rgba(34, 211, 238, 0.1), transparent 62%);
}

.header__strip-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  min-height: 58px;
  padding-block: 10px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}

.brand__mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  flex: 0 0 auto;
  background-color: var(--orange-500);
  color: var(--ink-900);
  font-family: var(--font-mono);
  font-size: 17px;
  font-weight: 700;
  line-height: 1;
  border: 2px solid var(--void);
  box-shadow: 3px 3px 0 0 var(--void);
  transition: transform var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.brand:hover .brand__mark {
  background-color: var(--orange-300);
  transform: translateY(-2px);
}

.brand__text {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}

.brand__name {
  font-family: var(--font-head);
  font-size: 18px;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--ice-50);
  white-space: nowrap;
}

.brand__line {
  font-size: 12px;
  line-height: 1.4;
  color: var(--slate-300);
  letter-spacing: 0.01em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.header__meta {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
}

.header__meta-text {
  font-size: 12px;
  color: var(--slate-300);
  border-bottom: 1px solid rgba(34, 211, 238, 0.45);
}

/* 下层：主导航 + 工具入口 */
.header__nav-inner {
  display: flex;
  align-items: center;
  gap: 16px;
  min-height: 62px;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 9px 14px;
  border: 2px solid var(--line-400);
  background-color: var(--ink-700);
  color: var(--ice-50);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.06em;
  box-shadow: 3px 3px 0 0 var(--void);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.nav-toggle:hover { border-color: var(--cyan-500); color: var(--cyan-300); }

.nav-toggle__bars {
  display: grid;
  gap: 3px;
  width: 16px;
}

.nav-toggle__bars i {
  display: block;
  height: 2px;
  background-color: currentColor;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(2) { opacity: 0; }

.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(1) { transform: translateY(5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }

.nav {
  display: flex;
  align-items: center;
  gap: clamp(12px, 2vw, 28px);
  flex: 1 1 auto;
  min-width: 0;
}

.nav__list {
  display: flex;
  align-items: center;
  gap: clamp(10px, 1.8vw, 24px);
  flex-wrap: wrap;
}

.nav__link {
  position: relative;
  display: inline-block;
  padding: 6px 2px 8px;
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--ice-50);
  border-bottom: 2px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.nav__link::before {
  content: "";
  position: absolute;
  left: -10px;
  top: 50%;
  width: 4px;
  height: 4px;
  background-color: var(--orange-500);
  transform: translateY(-50%) scale(0);
  transition: transform var(--dur) var(--ease);
}

.nav__link:hover,
.nav__link:focus-visible {
  color: var(--cyan-300);
  border-bottom-color: rgba(34, 211, 238, 0.55);
}

.nav__link:hover::before { transform: translateY(-50%) scale(1); }

.nav__link[aria-current="page"] {
  color: var(--cyan-300);
  border-bottom-color: var(--cyan-500);
}

.nav__link[aria-current="page"]::before { transform: translateY(-50%) scale(1); }

.nav__tools {
  display: flex;
  align-items: center;
  gap: 6px;
  flex: 0 0 auto;
  margin-left: auto;
  padding-left: clamp(12px, 2vw, 22px);
  border-left: 1px solid var(--line-400);
}

.nav__tool {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 10px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--slate-300);
  border: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.nav__tool:hover,
.nav__tool:focus-visible {
  color: var(--ink-900);
  background-color: var(--cyan-300);
  border-color: var(--cyan-300);
}

.nav__tool-dot {
  width: 5px;
  height: 5px;
  background-color: var(--cyan-500);
  flex: 0 0 auto;
  transition: background-color var(--dur) var(--ease);
}

.nav__tool:hover .nav__tool-dot { background-color: var(--ink-900); }

/* ============================================================
   按钮
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 22px;
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.01em;
  line-height: 1.3;
  color: var(--ice-50);
  background-color: var(--ink-700);
  border: 2px solid var(--line-400);
  box-shadow: 4px 4px 0 0 var(--void);
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease),
              border-color var(--dur) var(--ease), background-color var(--dur) var(--ease),
              color var(--dur) var(--ease);
}

.btn:hover {
  transform: translateY(-2px);
  border-color: var(--cyan-500);
  box-shadow: 6px 6px 0 0 var(--void);
}

.btn:active {
  transform: translateY(0);
  box-shadow: 2px 2px 0 0 var(--void);
}

.btn--accent {
  background-color: var(--orange-500);
  border-color: var(--ink-900);
  color: var(--ink-900);
}

.btn--accent:hover {
  background-color: var(--orange-300);
  border-color: var(--ink-900);
}

.btn--line {
  background-color: transparent;
  border-color: var(--cyan-500);
  color: var(--cyan-300);
}

.btn--line:hover {
  background-color: rgba(34, 211, 238, 0.12);
  color: var(--cyan-500);
}

.btn--ghost {
  background-color: transparent;
  border-color: transparent;
  box-shadow: none;
  color: var(--slate-300);
  padding-inline: 4px;
}

.btn--ghost:hover {
  color: var(--cyan-300);
  border-color: transparent;
  box-shadow: none;
  transform: none;
}

/* ============================================================
   面包屑
   ============================================================ */
.breadcrumb {
  padding-block: 14px;
  border-bottom: 1px solid rgba(36, 67, 102, 0.7);
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--slate-300);
}

.breadcrumb__item {
  display: inline-flex;
  align-items: center;
}

.breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  margin-inline: 10px;
  color: var(--line-400);
}

.breadcrumb__link {
  color: var(--slate-300);
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.breadcrumb__link:hover {
  color: var(--cyan-300);
  border-bottom-color: var(--cyan-500);
}

.breadcrumb__item[aria-current="page"] { color: var(--cyan-300); }

/* ============================================================
   网格
   ============================================================ */
.grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(16px, 2vw, 26px);
}

.span-3 { grid-column: span 3; }
.span-4 { grid-column: span 4; }
.span-5 { grid-column: span 5; }
.span-6 { grid-column: span 6; }
.span-7 { grid-column: span 7; }
.span-8 { grid-column: span 8; }
.span-9 { grid-column: span 9; }
.span-12 { grid-column: span 12; }
.offset-1 { grid-column-start: 2; }

/* ============================================================
   卡片
   ============================================================ */
.card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: clamp(18px, 2.4vw, 26px);
  background-color: var(--ink-700);
  border: 2px solid var(--line-400);
  box-shadow: var(--shadow-brut);
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease),
              border-color var(--dur) var(--ease);
}

.card:hover {
  transform: translateY(-2px);
  border-color: var(--cyan-500);
  box-shadow: var(--shadow-lift);
}

.card--raised {
  transform: translateY(-10px);
  box-shadow: var(--shadow-lift);
}

.card--raised:hover { transform: translateY(-12px); }

.card__label {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: 0.16em;
  color: var(--cyan-500);
}

.card__title {
  font-family: var(--font-head);
  font-size: clamp(18px, 2vw, 21px);
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--ice-50);
}

.card__body {
  font-size: 15px;
  line-height: 1.8;
  color: var(--slate-300);
}

/* ============================================================
   图片与媒体容器（页面阶段放占位图）
   ============================================================ */
.media-frame {
  position: relative;
  display: block;
  width: 100%;
  overflow: hidden;
  border: 2px solid var(--line-400);
  background-color: var(--ink-800);
  background-image:
    radial-gradient(115% 115% at 18% 12%, rgba(34, 211, 238, 0.18), transparent 58%),
    linear-gradient(135deg, var(--ink-700) 0%, var(--ink-800) 58%, var(--ink-900) 100%);
  box-shadow: var(--shadow-brut);
  transition: border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease),
              transform var(--dur) var(--ease);
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(125, 232, 247, 0.09) 1px, transparent 1px),
    linear-gradient(90deg, rgba(125, 232, 247, 0.09) 1px, transparent 1px);
  background-size: 34px 34px;
  pointer-events: none;
}

.media-frame:hover {
  border-color: var(--cyan-500);
  box-shadow: var(--shadow-lift);
}

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

.media-frame--wide { aspect-ratio: 16 / 9; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame--tall { aspect-ratio: 4 / 5; }

.media-frame__tag {
  position: absolute;
  top: 12px;
  left: 12px;
  z-index: 2;
}

.media-frame__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
  padding: 26px 16px 12px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.06em;
  color: var(--slate-300);
  background-image: linear-gradient(180deg, transparent, rgba(3, 10, 20, 0.9));
}

/* ============================================================
   标签
   ============================================================ */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 9px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.12em;
  line-height: 1.5;
  text-transform: uppercase;
  color: var(--slate-300);
  background-color: rgba(16, 42, 74, 0.72);
  border: 1px solid var(--line-400);
}

.tag--cyan {
  color: var(--ink-900);
  background-color: var(--cyan-500);
  border-color: var(--cyan-500);
}

.tag--accent {
  color: var(--ink-900);
  background-color: var(--orange-500);
  border-color: var(--orange-500);
}

.tag--mint {
  color: #04231F;
  background-color: var(--mint-500);
  border-color: var(--mint-500);
}

.tag--ghost {
  color: var(--cyan-300);
  background-color: transparent;
  border-color: var(--line-400);
}

/* ============================================================
   页脚
   ============================================================ */
.site-footer {
  position: relative;
  margin-top: clamp(48px, 7vw, 96px);
  border-top: 4px solid var(--line-400);
  background-image: linear-gradient(180deg, var(--ink-800) 0%, #050F1D 100%);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -4px;
  left: 0;
  width: min(260px, 42%);
  height: 4px;
  background-color: var(--orange-500);
}

.footer__top {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1.35fr;
  gap: clamp(24px, 3.4vw, 44px);
  padding-block: clamp(40px, 5.5vw, 66px) clamp(28px, 4vw, 44px);
}

.footer__brand {
  display: flex;
  flex-direction: column;
  gap: 14px;
  align-items: flex-start;
}

.brand--footer .brand__mark {
  background-color: var(--ink-700);
  color: var(--cyan-500);
  border-color: var(--cyan-500);
}

.brand--footer:hover .brand__mark {
  background-color: var(--cyan-500);
  color: var(--ink-900);
}

.footer__line {
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--ice-50);
  max-width: 26ch;
}

.footer__note {
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--slate-300);
  max-width: 30ch;
}

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

.footer__title {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cyan-500);
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line-400);
}

.footer__links {
  display: grid;
  gap: 9px;
}

.footer__link {
  display: inline-block;
  font-size: 14px;
  color: var(--slate-300);
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.footer__link:hover,
.footer__link:focus-visible {
  color: var(--cyan-300);
  border-bottom-color: var(--cyan-500);
}

.footer__contact {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer__contact-row {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px;
  font-size: 13.5px;
  color: var(--ice-50);
}

.footer__label {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--slate-300);
  padding: 2px 6px;
  border: 1px solid var(--line-400);
}

.footer__contact-row .mono {
  color: var(--cyan-300);
  font-size: 13px;
  border-bottom: 1px solid rgba(34, 211, 238, 0.4);
  word-break: break-all;
}

.copy-btn {
  padding: 3px 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--ink-900);
  background-color: var(--cyan-500);
  border: 1px solid var(--cyan-500);
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease),
              border-color var(--dur) var(--ease);
}

.copy-btn:hover {
  background-color: var(--cyan-300);
  border-color: var(--cyan-300);
}

.copy-hint {
  min-height: 1.2em;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.03em;
  color: var(--mint-500);
}

.footer__service {
  font-size: 12.5px;
  line-height: 1.75;
  color: var(--slate-300);
  padding-top: 10px;
  border-top: 1px dashed var(--line-400);
}

.footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding-block: 18px 26px;
  border-top: 1px solid var(--line-400);
}

.footer__legal {
  font-size: 12.5px;
  color: var(--slate-300);
}

.footer__legal .mono {
  color: var(--ice-50);
  font-size: 12px;
  border-bottom: 1px solid rgba(34, 211, 238, 0.4);
}

.footer__legal-links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px;
}

.to-top {
  padding: 8px 14px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--ice-50);
  background-color: var(--ink-700);
  border: 2px solid var(--line-400);
  box-shadow: 3px 3px 0 0 var(--void);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease),
              color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.to-top:hover {
  transform: translateY(-2px);
  color: var(--ink-900);
  background-color: var(--cyan-500);
  border-color: var(--cyan-500);
}

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 1080px) {
  .footer__top { grid-template-columns: 1fr 1fr; }
  .footer__brand { grid-column: 1 / -1; }
}

@media (max-width: 980px) {
  .nav-toggle { display: inline-flex; }

  .nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    z-index: 70;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 12px var(--pad) 22px;
    background-color: var(--ink-800);
    background-image: linear-gradient(180deg, var(--ink-800), #06121F);
    border-top: 2px solid var(--line-400);
    border-bottom: 2px solid var(--line-400);
    box-shadow: 0 26px 44px -26px rgba(0, 0, 0, 0.95);
    max-height: calc(100vh - 120px);
    overflow-y: auto;
  }

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

  .nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    flex-wrap: nowrap;
  }

  .nav__item { border-bottom: 1px solid rgba(36, 67, 102, 0.55); }

  .nav__link {
    display: block;
    padding: 13px 4px;
    font-size: 16px;
    border-bottom: 0;
    border-left: 3px solid transparent;
  }

  .nav__link:hover,
  .nav__link:focus-visible,
  .nav__link[aria-current="page"] {
    border-bottom-color: transparent;
    border-left-color: var(--cyan-500);
    padding-left: 10px;
  }

  .nav__link::before { display: none; }

  .nav__tools {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
    margin: 16px 0 0;
    padding: 16px 0 0;
    border-left: 0;
    border-top: 1px solid var(--line-400);
  }

  .nav__tool {
    justify-content: flex-start;
    padding: 9px 10px;
    border-color: var(--line-400);
    background-color: rgba(16, 42, 74, 0.6);
  }

  .header__strip-inner { min-height: 54px; }

  .grid { grid-template-columns: repeat(6, minmax(0, 1fr)); }
  .span-3, .span-4, .span-5 { grid-column: span 3; }
  .span-6, .span-7, .span-8, .span-9, .span-12 { grid-column: span 6; }
  .offset-1 { grid-column-start: auto; }
  .card--raised { transform: none; }
  .card--raised:hover { transform: translateY(-2px); }
}

@media (max-width: 640px) {
  body { font-size: 15.5px; }

  .brand__line { display: none; }
  .brand__name { font-size: 16.5px; }
  .header__meta-text { display: none; }
  .header__strip-inner { min-height: 50px; }

  .footer__top { grid-template-columns: 1fr; gap: 28px; }
  .footer__bottom { flex-direction: column; align-items: flex-start; gap: 12px; }
  .footer__legal-links { gap: 14px; }

  .grid { grid-template-columns: minmax(0, 1fr); }
  .span-3, .span-4, .span-5, .span-6, .span-7, .span-8, .span-9, .span-12 {
    grid-column: span 1;
  }

  .btn { width: 100%; }
  .nav .btn { width: auto; }
}

/* ============================================================
   动效偏好
   ============================================================ */
@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;
  }

  .card:hover,
  .card--raised,
  .card--raised:hover,
  .btn:hover,
  .media-frame:hover,
  .to-top:hover,
  .brand:hover .brand__mark {
    transform: none;
  }
}

/* 打印 */
@media print {
  .site-header,
  .site-footer,
  .skip-link,
  .progress,
  .to-top { display: none !important; }

  body { background: #fff; color: #071426; }
  .card, .media-frame { box-shadow: none; border-color: #244366; }
}