/* ==========================================================================
   完美体育 · 共享样式 /assets/site.css
   夜间数据作战室：墨蓝底、玻璃刊头、等宽数据、青橙双信号色
   ========================================================================== */

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

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

body,
h1, h2, h3, h4, h5, h6,
p, figure, blockquote, dl, dd, ul, ol { margin: 0; }

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

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

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

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

input, select, textarea { font: inherit; }

[hidden] { display: none !important; }

/* ---------- 2. 设计变量 ---------- */
:root {
  /* 墨蓝底 · 深舱蓝 · 边框蓝 */
  --ink-0: #071523;
  --ink-1: #0C2238;
  --ink-2: #10293F;
  --ink-3: #14324A;
  --line: #1E3A52;
  --line-soft: rgba(30, 58, 82, 0.55);

  /* 信号色 */
  --cyan: #35F2D0;
  --orange: #FF7A3D;
  --moss: #6F8B72;
  --clay: #B66A4A;

  /* 文本 */
  --paper: #F4F0E8;
  --stone: #8C948F;
  --text: #D7E2EA;
  --text-dim: #9FB0BC;

  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;

  --shell-max: 1320px;
  --pad: clamp(16px, 4vw, 44px);
  --radius: 2px;

  --ease: cubic-bezier(0.4, 0.15, 0.15, 1);
  --dur: 160ms;

  --header-line: 48px;
}

/* ---------- 3. 基础排版 ---------- */
body {
  min-height: 100vh;
  background-color: var(--ink-0);
  background-image:
    radial-gradient(1100px 560px at 84% -8%, rgba(53, 242, 208, 0.07), transparent 62%),
    radial-gradient(820px 460px at 4% 1%, rgba(255, 122, 61, 0.05), transparent 58%),
    repeating-linear-gradient(0deg, rgba(30, 58, 82, 0.2) 0 1px, transparent 1px 88px),
    repeating-linear-gradient(90deg, rgba(30, 58, 82, 0.2) 0 1px, transparent 1px 88px);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  font-weight: 400;
  letter-spacing: 0.01em;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  color: var(--paper);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.01em;
}

h1 {
  font-size: clamp(34px, 5.4vw, 68px);
  font-weight: 600;
  letter-spacing: -0.025em;
  line-height: 1.08;
}

h2 {
  font-size: clamp(24px, 3vw, 36px);
  letter-spacing: -0.015em;
}

h3 {
  font-size: clamp(17px, 1.9vw, 21px);
  font-weight: 800;
}

h4 {
  font-size: 16px;
  font-weight: 800;
}

strong, b { font-weight: 800; color: var(--paper); }

::selection {
  background: rgba(53, 242, 208, 0.28);
  color: var(--paper);
}

:where(h1, h2, h3, h4, [id]) { scroll-margin-top: 140px; }

/* ---------- 4. 焦点可见 ---------- */
a:focus-visible,
button:focus-visible,
summary:focus-visible,
[tabindex]:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: var(--radius);
}

/* ---------- 5. 容器与节奏 ---------- */
.shell {
  width: 100%;
  max-width: var(--shell-max);
  margin-inline: auto;
  padding-inline: var(--pad);
}

.section {
  padding-block: clamp(48px, 7vw, 96px);
}

.divider {
  height: 1px;
  border: 0;
  background: var(--line);
  margin-block: clamp(24px, 4vw, 48px);
}

/* ---------- 6. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.06em;
  line-height: 1.2;
  border: 1px solid transparent;
  border-radius: var(--radius);
  white-space: nowrap;
  transition: background-color var(--dur) var(--ease),
    color var(--dur) var(--ease),
    border-color var(--dur) var(--ease),
    transform var(--dur) var(--ease);
}

.btn--primary {
  background: var(--orange);
  color: #1B0A02;
  box-shadow: 0 0 0 1px rgba(255, 122, 61, 0.35), 0 10px 26px -14px rgba(255, 122, 61, 0.95);
}

.btn--primary:hover {
  background: #FF9463;
  transform: translateY(-1px);
}

.btn--ghost {
  border-color: var(--line);
  background: rgba(12, 34, 56, 0.6);
  color: #C9D8E2;
}

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

.btn--cyan {
  background: var(--cyan);
  color: #04121C;
}

.btn--cyan:hover {
  background: #6BF7DF;
}

/* ---------- 7. 页头 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(7, 21, 35, 0.84);
  -webkit-backdrop-filter: blur(18px) saturate(140%);
  backdrop-filter: blur(18px) saturate(140%);
  border-bottom: 1px solid var(--line);
  transition: box-shadow var(--dur) var(--ease);
}

.site-header[data-scrolled] {
  box-shadow: 0 22px 48px -34px #000;
}

/* 跳转链接 */
.skip-link {
  position: fixed;
  left: var(--pad);
  top: 8px;
  z-index: 200;
  padding: 10px 18px;
  background: var(--cyan);
  color: #04121C;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.04em;
  border-radius: var(--radius);
  transform: translateY(-180%);
  transition: transform var(--dur) var(--ease);
}

.skip-link:focus-visible {
  transform: translateY(0);
  outline-offset: 2px;
}

/* 7.1 同步带 */
.sync-strip {
  background: linear-gradient(90deg, #0A1B2B, #0C2238 52%, #0A1B2B);
  border-bottom: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--stone);
}

.sync-strip__inner {
  display: flex;
  align-items: center;
  gap: 18px;
  min-height: 38px;
  padding-block: 6px;
}

.sync-strip__status {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  color: var(--paper);
  white-space: nowrap;
}

.sync-strip__time {
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.pulse-dot {
  width: 7px;
  height: 7px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 0 rgba(53, 242, 208, 0.55);
  animation: pulse-ring 2.6s var(--ease) infinite;
}

@keyframes pulse-ring {
  0% { box-shadow: 0 0 0 0 rgba(53, 242, 208, 0.5); }
  70% { box-shadow: 0 0 0 9px rgba(53, 242, 208, 0); }
  100% { box-shadow: 0 0 0 0 rgba(53, 242, 208, 0); }
}

.sync-strip__note {
  flex: 1;
  text-align: center;
  color: var(--stone);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.sync-strip__link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--orange);
  font-weight: 700;
  letter-spacing: 0.06em;
  white-space: nowrap;
  transition: color var(--dur) var(--ease);
}

.sync-strip__link:hover { color: var(--paper); }

.sync-strip__arrow {
  transition: transform var(--dur) var(--ease);
}

.sync-strip__link:hover .sync-strip__arrow { transform: translateX(3px); }

/* 7.2 刊头 */
.masthead {
  position: relative;
  background: linear-gradient(180deg, rgba(12, 34, 56, 0.7), rgba(7, 21, 35, 0.45));
}

.masthead::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    90deg,
    rgba(30, 58, 82, 0.5) 0 1px,
    transparent 1px 46px
  );
  opacity: 0.32;
}

.masthead__inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: clamp(12px, 2vw, 32px);
  min-height: 78px;
  padding-block: 12px;
  transition: min-height var(--dur) var(--ease);
}

.site-header[data-scrolled] .masthead__inner { min-height: 62px; }

/* 7.3 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  justify-self: start;
}

.brand__mark {
  display: flex;
  align-items: flex-end;
  gap: 3px;
  height: 26px;
  width: 21px;
  flex: 0 0 auto;
}

.brand__mark span {
  display: block;
  width: 5px;
  border-radius: 1px;
  background: var(--cyan);
  transition: height var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.brand__mark span:nth-child(1) { height: 52%; opacity: 0.6; }
.brand__mark span:nth-child(2) { height: 100%; }
.brand__mark span:nth-child(3) { height: 74%; background: var(--orange); }

.brand:hover .brand__mark span:nth-child(2) { background: var(--paper); }
.brand:hover .brand__mark span:nth-child(3) { height: 100%; }

.brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}

.brand__name {
  font-size: 19px;
  font-weight: 800;
  letter-spacing: 0.06em;
  color: var(--paper);
}

.brand__sub {
  margin-top: 3px;
  font-family: var(--font-mono);
  font-size: 9.5px;
  letter-spacing: 0.28em;
  color: var(--stone);
}

/* 7.4 居中栏目 */
.nav {
  justify-self: center;
  position: relative;
}

.nav__list {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(4px, 1.2vw, 20px);
}

.nav__link {
  position: relative;
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 10px 4px;
  font-size: 15px;
  font-weight: 500;
  color: #BFD3DF;
  letter-spacing: 0.02em;
  transition: color var(--dur) var(--ease);
}

.nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 2px;
  height: 2px;
  background: var(--orange);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.nav__link:hover { color: var(--paper); }
.nav__link:hover::after { transform: scaleX(1); background: var(--cyan); }

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

.nav__link[aria-current="page"]::after { transform: scaleX(1); }

.nav__index {
  font-family: var(--font-mono);
  font-size: 9.5px;
  letter-spacing: 0.1em;
  color: var(--stone);
  transition: color var(--dur) var(--ease);
}

.nav__link[aria-current="page"] .nav__index { color: var(--orange); }
.nav__link:hover .nav__index { color: var(--cyan); }

.nav__label { display: inline-block; }

/* 7.5 右侧动作 */
.masthead__actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 10px;
  justify-self: end;
}

.masthead__actions .btn { padding: 10px 16px; font-size: 13.5px; }

/* 7.6 移动端开关 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 9px 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

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

.nav-toggle__bars {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  width: 16px;
  height: 12px;
}

.nav-toggle__bars span {
  display: block;
  width: 100%;
  height: 2px;
  background: currentColor;
  border-radius: 1px;
  transition: transform var(--dur) var(--ease);
}

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

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

.nav-toggle__label { line-height: 1; }

/* 7.7 阅读进度仪表 */
.read-meter {
  position: absolute;
  left: 0;
  bottom: -1px;
  z-index: 3;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--cyan), var(--orange));
  transform: scaleX(0);
  transform-origin: 0 50%;
  pointer-events: none;
}

/* ---------- 8. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(48px, 8vw, 120px);
  background: linear-gradient(180deg, #081826 0%, #050F19 62%, #040D15 100%);
  border-top: 1px solid var(--line);
  color: var(--stone);
  font-size: 14px;
  padding-block: clamp(40px, 6vw, 72px) clamp(24px, 4vw, 40px);
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: -1px 0 auto 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--cyan) 20%, var(--orange) 68%, transparent 96%);
  opacity: 0.75;
}

.footer-top {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 2fr);
  gap: clamp(28px, 5vw, 72px);
  align-items: start;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 14px;
  max-width: 34ch;
}

.footer-brand .brand { justify-self: start; }

.footer-brand__note {
  color: var(--text-dim);
  font-size: 14.5px;
  line-height: 1.7;
}

.footer-brand__meta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--moss);
}

.footer-brand__dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--moss);
  box-shadow: 0 0 0 3px rgba(111, 139, 114, 0.16);
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 44px);
}

.fcol { min-width: 0; }

.fcol__toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  width: 100%;
  padding: 0 0 12px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  cursor: default;
}

.fcol__title {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.fcol__chev { display: none; }

.fcol__body { padding-top: 16px; }

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

.fcol__item {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.fcol__key {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  color: var(--stone);
  text-transform: uppercase;
}

.fcol__val {
  color: #C9D8E2;
  font-size: 14px;
  line-height: 1.6;
  word-break: break-word;
}

.fcol__val--mono {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0;
  color: var(--paper);
}

.fcol__note {
  margin-top: 14px;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--stone);
}

.fcol__note--mono {
  margin-top: 16px;
  font-family: var(--font-mono);
  letter-spacing: 0.06em;
  color: var(--text-dim);
}

.fcol__links {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.fcol__link {
  display: inline-block;
  padding: 5px 0;
  color: var(--text-dim);
  font-size: 14.5px;
  transition: color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.fcol__link:hover {
  color: var(--cyan);
  transform: translateX(3px);
}

.footer-base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-top: clamp(28px, 4vw, 48px);
  padding-top: 20px;
  border-top: 1px solid var(--line-soft);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--stone);
}

.footer-base__copy,
.footer-base__meta { line-height: 1.7; }

/* ---------- 9. 通用内容组件 ---------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--cyan);
}

.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: var(--orange);
  flex: 0 0 auto;
}

.prose { max-width: 68ch; }

.prose > * + * { margin-top: 1.05em; }

.prose h2,
.prose h3 {
  margin-top: 2em;
  margin-bottom: 0.6em;
  color: var(--paper);
}

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

.prose ol { list-style: decimal; }

.prose li + li { margin-top: 0.4em; }

.prose strong { color: var(--cyan); }

.prose a {
  color: var(--orange);
  border-bottom: 1px solid rgba(255, 122, 61, 0.36);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.prose a:hover {
  color: var(--paper);
  border-color: var(--paper);
}

.prose blockquote {
  padding-left: 18px;
  border-left: 2px solid var(--orange);
  color: var(--text-dim);
}

/* 面包屑 */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--stone);
}

.breadcrumb a { color: var(--stone); transition: color var(--dur) var(--ease); }
.breadcrumb a:hover { color: var(--cyan); }
.breadcrumb__sep { color: var(--line); }
.breadcrumb [aria-current="page"] { color: var(--paper); }

/* 栅格 */
.grid {
  display: grid;
  gap: clamp(14px, 2vw, 26px);
  grid-template-columns: minmax(0, 1fr);
}

/* 卡片 */
.card {
  position: relative;
  padding: clamp(16px, 2vw, 24px);
  background: linear-gradient(180deg, rgba(16, 41, 63, 0.92), rgba(12, 34, 56, 0.76));
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.card--flush { padding: 0; }

/* 标签 */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--stone);
  border: 1px solid var(--line);
  border-radius: 999px;
  line-height: 1.6;
  white-space: nowrap;
}

.tag--cyan { color: var(--cyan); border-color: rgba(53, 242, 208, 0.35); }
.tag--orange { color: var(--orange); border-color: rgba(255, 122, 61, 0.42); }

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

/* 图片容器基础规则 */
.figure {
  position: relative;
  display: block;
  width: 100%;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(158deg, var(--ink-2), var(--ink-0));
}

.figure::before {
  content: "";
  display: block;
  padding-top: var(--figure-ratio, 62%);
}

.figure > img,
.figure > svg,
.figure > video,
.figure > .figure__ph {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.figure__ph {
  display: grid;
  place-items: center;
  padding: 12px;
  text-align: center;
  background-image:
    repeating-linear-gradient(90deg, rgba(30, 58, 82, 0.55) 0 1px, transparent 1px 32px),
    repeating-linear-gradient(0deg, rgba(30, 58, 82, 0.4) 0 1px, transparent 1px 32px);
  color: var(--stone);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.figure--wide { --figure-ratio: 42%; }
.figure--tall { --figure-ratio: 118%; }
.figure--square { --figure-ratio: 100%; }

/* ---------- 10. 响应式 ---------- */
@media (min-width: 640px) {
  .grid--2,
  .grid--3,
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 980px) {
  .grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}

@media (max-width: 1180px) {
  .nav__index { display: none; }
  .masthead__ghost { display: none; }
  .nav__link { font-size: 14.5px; padding-inline: 2px; }
}

@media (max-width: 980px) {
  .masthead__inner {
    grid-template-columns: 1fr auto;
    min-height: 66px;
  }

  .site-header[data-scrolled] .masthead__inner { min-height: 58px; }

  .nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: none;
    justify-self: stretch;
    z-index: 4;
    padding: 8px var(--pad) 24px;
    background: var(--ink-1);
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
    box-shadow: 0 34px 64px -36px #000;
    max-height: calc(100dvh - 120px);
    overflow-y: auto;
  }

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

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

  .nav__item + .nav__item { border-top: 1px solid var(--line-soft); }

  .nav__link {
    display: flex;
    align-items: baseline;
    padding: 15px 2px;
    font-size: 16.5px;
  }

  .nav__link::after {
    left: auto;
    right: 0;
    bottom: 50%;
    width: 3px;
    height: 0;
    transform: none;
    transition: height var(--dur) var(--ease);
  }

  .nav__link:hover::after,
  .nav__link[aria-current="page"]::after {
    transform: none;
    height: 18px;
    margin-bottom: -9px;
  }

  .nav__index { display: inline-block; font-size: 10.5px; color: var(--moss); }

  .nav-toggle { display: inline-flex; }

  .footer-top {
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
  }

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

  .fcol { border-top: 1px solid var(--line-soft); }

  .fcol__toggle {
    cursor: pointer;
    padding: 16px 0;
    border-bottom: 0;
  }

  .fcol__chev {
    display: block;
    width: 9px;
    height: 9px;
    border-right: 1.5px solid var(--stone);
    border-bottom: 1.5px solid var(--stone);
    transform: rotate(45deg);
    transition: transform var(--dur) var(--ease);
  }

  .fcol__toggle[aria-expanded="true"] .fcol__chev {
    transform: rotate(225deg);
    border-color: var(--cyan);
  }

  .fcol__body {
    display: none;
    padding-top: 0;
    padding-bottom: 20px;
  }

  .fcol__toggle[aria-expanded="true"] + .fcol__body { display: block; }
}

@media (max-width: 720px) {
  .sync-strip__inner {
    justify-content: space-between;
    gap: 10px;
    min-height: 32px;
    padding-block: 4px;
  }

  .sync-strip__note { display: none; }
  .sync-strip { font-size: 10.5px; }
  .brand__name { font-size: 17px; }
  .brand__sub { font-size: 8.5px; letter-spacing: 0.22em; }
  .brand__mark { height: 22px; }
}

@media (max-width: 560px) {
  .masthead__actions { gap: 8px; }
  .masthead__actions .btn { padding: 9px 12px; font-size: 13px; letter-spacing: 0.02em; }
  .nav-toggle { padding: 8px 10px; }
  .footer-base { flex-direction: column; align-items: flex-start; gap: 6px; }
}

/* ---------- 11. 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;
  }

  .pulse-dot { animation: none; box-shadow: 0 0 0 3px rgba(53, 242, 208, 0.22); }
  .nav__link:hover::after,
  .nav__link[aria-current="page"]::after { transform: none; }
  .fcol__link:hover { transform: none; }
  .btn--primary:hover { transform: none; }
}