/* ==========================================================================
   TITAN哨响 / 6688体育 · 共享样式表  /assets/site.css
   色序：深空蓝 36% · 炭黑 16% · 岩灰 9% · 冷银系 16% · 警示橙 9% · 雾绿/日晒黄 6%
   ========================================================================== */

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

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

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

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

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

button, input, select, textarea { font: inherit; color: inherit; }

table { border-collapse: collapse; width: 100%; }

a { color: inherit; }

/* ---------- 2. 变量 ---------- */
:root {
  --tt-space: #0B1524;
  --tt-carbon: #14171C;
  --tt-rock: #2A3138;
  --tt-silver: #C6CDD6;
  --tt-silver-2: #E9EDF2;
  --tt-orange: #FF5A1F;
  --tt-orange-deep: #C63C0E;
  --tt-mist: #6E8B7A;
  --tt-moss: #3F5A4B;
  --tt-sun: #E8B23A;
  --tt-cream: #F2EFE7;

  --tt-line: rgba(198, 205, 214, 0.16);
  --tt-line-strong: rgba(198, 205, 214, 0.38);
  --tt-line-ink: rgba(20, 23, 28, 0.14);

  --tt-shell: 1280px;
  --tt-gutter: clamp(18px, 5vw, 56px);
  --tt-radius: 16px 4px 16px 4px;
  --tt-radius-soft: 20px 6px 16px 8px;

  --tt-font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", sans-serif;
  --tt-font-narrow: "Arial Narrow", "Helvetica Neue Condensed", "Roboto Condensed", "PingFang SC", system-ui, sans-serif;
  --tt-font-num: ui-monospace, "SFMono-Regular", Menlo, Consolas, "Roboto Mono", "Courier New", monospace;
}

/* ---------- 3. 中文排版基座 ---------- */
body {
  background-color: var(--tt-space);
  color: var(--tt-silver-2);
  font-family: var(--tt-font);
  font-size: 17px;
  line-height: 1.85;
  letter-spacing: 0.01em;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1, h2, h3, h4 {
  font-weight: 800;
  line-height: 1.22;
  letter-spacing: -0.01em;
  color: var(--tt-silver-2);
}

h1 { font-size: clamp(30px, 4.4vw, 44px); }
h2 { font-size: clamp(26px, 3.4vw, 36px); }
h3 { font-size: clamp(20px, 2.2vw, 28px); }
h4 { font-size: 18px; }

p { max-width: 64ch; }

::selection { background: var(--tt-orange); color: var(--tt-space); }

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

/* ---------- 4. 跳转链接 ---------- */
.tt-skip {
  position: fixed;
  left: -9999px;
  top: 0;
  z-index: 200;
  padding: 12px 22px;
  background: var(--tt-orange);
  color: var(--tt-space);
  font-weight: 700;
  letter-spacing: 0.06em;
  text-decoration: none;
  border-radius: 0 0 14px 0;
}
.tt-skip:focus { left: 0; }

/* ---------- 5. 布局容器 ---------- */
.tt-shell {
  width: 100%;
  max-width: var(--tt-shell);
  margin-inline: auto;
  padding-inline: var(--tt-gutter);
}

.tt-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(16px, 2.2vw, 28px);
}

.tt-section { padding-block: clamp(48px, 7vw, 104px); }
.tt-section--cream { background: var(--tt-cream); color: #14171C; }
.tt-section--cream h1,
.tt-section--cream h2,
.tt-section--cream h3,
.tt-section--cream h4 { color: #14171C; }
.tt-section--carbon { background: var(--tt-carbon); }
.tt-section--rock { background: var(--tt-rock); }

.tt-prose {
  max-width: 64ch;
  font-size: 17px;
  line-height: 1.88;
  color: var(--tt-silver-2);
}
.tt-prose > * + * { margin-top: 1.1em; }
.tt-prose a { color: var(--tt-orange); text-decoration: none; border-bottom: 1px solid rgba(255, 90, 31, 0.45); }
.tt-prose a:hover { border-bottom-color: var(--tt-orange); }
.tt-prose--ink { color: #14171C; }
.tt-prose--ink a { color: var(--tt-moss); border-bottom-color: rgba(63, 90, 75, 0.5); }

.tt-lede {
  max-width: 52ch;
  font-size: clamp(18px, 2vw, 22px);
  line-height: 1.7;
  color: var(--tt-silver);
}

/* ---------- 6. 排版组件 ---------- */
.tt-label {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-size: 11.5px;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--tt-mist);
}
.tt-label::before {
  content: "";
  width: 16px;
  height: 1px;
  background: currentColor;
}
.tt-label--ink { color: var(--tt-moss); }
.tt-label--hot { color: var(--tt-orange); }

.tt-display {
  display: block;
  font-family: var(--tt-font-narrow);
  font-weight: 900;
  font-size: clamp(56px, 13vw, 160px);
  line-height: 0.86;
  letter-spacing: -0.02em;
  text-transform: uppercase;
  color: var(--tt-silver-2);
}
.tt-display--hot { color: var(--tt-orange); }
.tt-display--ghost {
  color: transparent;
  -webkit-text-stroke: 1px var(--tt-line-strong);
}

.tt-num {
  font-family: var(--tt-font-num);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.06em;
  font-style: normal;
}

/* ---------- 7. 按钮 ---------- */
.tt-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 24px;
  font-size: 14.5px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-decoration: none;
  border: 1px solid transparent;
  border-radius: var(--tt-radius);
  cursor: pointer;
  transition: background-color 0.24s ease, color 0.24s ease, border-color 0.24s ease, transform 0.24s ease;
}
.tt-btn::after {
  content: "\2192";
  font-size: 15px;
  line-height: 1;
  transition: transform 0.24s ease;
}
.tt-btn:hover::after { transform: translateX(3px); }
.tt-btn--solid { background: var(--tt-orange); color: var(--tt-space); }
.tt-btn--solid:hover { background: var(--tt-orange-deep); color: var(--tt-silver-2); }
.tt-btn--ghost {
  border-color: var(--tt-line-strong);
  color: var(--tt-silver-2);
  background: rgba(198, 205, 214, 0.03);
}
.tt-btn--ghost:hover { border-color: var(--tt-orange); color: var(--tt-orange); }
.tt-btn--quiet {
  padding: 8px 0;
  color: var(--tt-orange);
  background: none;
  border: 0;
}
.tt-btn--quiet:hover { color: var(--tt-sun); }

/* ---------- 8. 面包屑 ---------- */
.tt-crumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  padding-block: 20px;
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--tt-mist);
}
.tt-crumb a {
  text-decoration: none;
  border-bottom: 1px solid var(--tt-line);
  transition: color 0.2s ease, border-color 0.2s ease;
}
.tt-crumb a:hover { color: var(--tt-orange); border-bottom-color: var(--tt-orange); }
.tt-crumb__sep { opacity: 0.5; }
.tt-crumb [aria-current="page"] { color: var(--tt-silver-2); }

/* ---------- 9. 卡片 / 证据列 / 状态 ---------- */
.tt-card {
  position: relative;
  background: var(--tt-rock);
  border: 1px solid var(--tt-line);
  border-radius: var(--tt-radius-soft);
  padding: clamp(20px, 3vw, 34px);
}
.tt-card--paper {
  background: var(--tt-cream);
  color: #14171C;
  border-color: var(--tt-line-ink);
}
.tt-card--paper h1, .tt-card--paper h2, .tt-card--paper h3, .tt-card--paper h4 { color: #14171C; }
.tt-card--flat { background: transparent; border-style: dashed; }

.tt-evidence { display: flex; flex-direction: column; gap: 6px; }
.tt-evidence__num {
  font-family: var(--tt-font-num);
  font-variant-numeric: tabular-nums;
  font-size: clamp(28px, 4vw, 44px);
  font-weight: 700;
  letter-spacing: 0.03em;
  line-height: 1.1;
  color: var(--tt-silver-2);
}
.tt-evidence__tag {
  font-size: 11.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--tt-mist);
}
.tt-evidence--hot .tt-evidence__num { color: var(--tt-orange); }

.tt-signal {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 6px 14px;
  font-size: 11.5px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--tt-silver);
  border: 1px solid var(--tt-line-strong);
  border-radius: 999px 6px 999px 6px;
  background: linear-gradient(120deg, rgba(198, 205, 214, 0.14), rgba(198, 205, 214, 0.02));
}
.tt-signal::before {
  content: "";
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--tt-sun);
  box-shadow: 0 0 0 3px rgba(232, 178, 58, 0.16);
}
.tt-signal--live::before {
  background: var(--tt-orange);
  box-shadow: 0 0 0 3px rgba(255, 90, 31, 0.18);
}

/* ---------- 10. 章节轨道 / 赛道带 ---------- */
.tt-rail {
  position: relative;
  padding-left: 26px;
  border-left: 1px solid var(--tt-line-strong);
}
.tt-rail__item {
  position: relative;
  padding: 11px 0;
  font-size: 14px;
  letter-spacing: 0.05em;
  color: var(--tt-mist);
  transition: color 0.24s ease;
}
.tt-rail__item a { text-decoration: none; }
.tt-rail__item.is-active { color: var(--tt-silver-2); }
.tt-rail__item.is-active::before {
  content: "";
  position: absolute;
  left: -31px;
  top: 50%;
  width: 9px;
  height: 9px;
  margin-top: -5px;
  background: var(--tt-orange);
  border-radius: 50%;
}

.tt-track {
  display: flex;
  gap: 16px;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  padding-bottom: 16px;
  scrollbar-width: thin;
  scrollbar-color: var(--tt-rock) transparent;
}
.tt-track::-webkit-scrollbar { height: 4px; }
.tt-track::-webkit-scrollbar-thumb { background: var(--tt-rock); }
.tt-track__item {
  flex: 0 0 clamp(240px, 32vw, 350px);
  scroll-snap-align: start;
}

/* ---------- 11. 图片容器（页面阶段放置占位或 img） ---------- */
.tt-media {
  position: relative;
  aspect-ratio: 16 / 10;
  overflow: hidden;
  border-radius: var(--tt-radius-soft);
  background:
    linear-gradient(135deg, rgba(110, 139, 122, 0.16), transparent 60%),
    linear-gradient(315deg, rgba(255, 90, 31, 0.10), transparent 55%),
    var(--tt-rock);
}
.tt-media > img,
.tt-media > picture,
.tt-media > video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.tt-media--wide { aspect-ratio: 21 / 9; }
.tt-media--tall { aspect-ratio: 4 / 5; }
.tt-media--square { aspect-ratio: 1 / 1; }
.tt-media__frame {
  position: absolute;
  inset: 10px;
  border: 1px dashed var(--tt-line);
  border-radius: 12px 3px 12px 3px;
  pointer-events: none;
}
.tt-media__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 20px 22px 16px;
  font-size: 13px;
  letter-spacing: 0.05em;
  color: var(--tt-silver);
  background: linear-gradient(to top, rgba(11, 21, 36, 0.94), rgba(11, 21, 36, 0));
}

/* ---------- 12. 页头 ---------- */
.tt-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(11, 21, 36, 0.95);
  border-bottom: 1px solid var(--tt-line);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}
.tt-header__glow {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(112deg, rgba(110, 139, 122, 0.13) 0 13%, transparent 13.1%),
    linear-gradient(90deg, transparent 64%, rgba(255, 90, 31, 0.07) 64.1% 100%);
}

.tt-header__inner {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding-block: 18px;
  transition: padding 0.28s ease;
}
.tt-header[data-scrolled="true"] .tt-header__inner { padding-block: 11px; }

/* 品牌锁 */
.tt-brand {
  display: inline-flex;
  align-items: center;
  gap: 13px;
  text-decoration: none;
  flex: 0 0 auto;
}
.tt-brand__mark {
  position: relative;
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border: 1px solid var(--tt-line-strong);
  border-radius: 11px 3px 11px 3px;
  background: linear-gradient(145deg, rgba(198, 205, 214, 0.18), rgba(11, 21, 36, 0));
  transition: width 0.28s ease, height 0.28s ease;
}
.tt-brand__mark::before {
  content: "";
  width: 13px;
  height: 13px;
  background: var(--tt-silver);
  clip-path: polygon(50% 0, 100% 50%, 50% 100%, 0 50%);
}
.tt-brand__pulse {
  position: absolute;
  right: -3px;
  top: -3px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--tt-orange);
  box-shadow: 0 0 0 3px rgba(255, 90, 31, 0.2);
}
.tt-brand__text { display: flex; flex-direction: column; gap: 2px; }
.tt-brand__name {
  font-size: 19px;
  font-weight: 900;
  letter-spacing: -0.01em;
  line-height: 1.1;
  color: var(--tt-silver-2);
}
.tt-brand__sub {
  font-size: 10.5px;
  letter-spacing: 0.14em;
  color: var(--tt-mist);
  max-height: 20px;
  overflow: hidden;
  transition: max-height 0.28s ease, opacity 0.24s ease;
}
.tt-header[data-scrolled="true"] .tt-brand__mark { width: 28px; height: 28px; }
.tt-header[data-scrolled="true"] .tt-brand__sub { max-height: 0; opacity: 0; }

/* 移动按钮 */
.tt-navtoggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 10px 15px;
  background: transparent;
  border: 1px solid var(--tt-line-strong);
  border-radius: var(--tt-radius);
  color: var(--tt-silver-2);
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: 0.14em;
  cursor: pointer;
  transition: border-color 0.24s ease, color 0.24s ease;
}
.tt-navtoggle:hover { border-color: var(--tt-orange); color: var(--tt-orange); }
.tt-navtoggle__bar {
  position: relative;
  display: block;
  width: 17px;
  height: 2px;
  background: currentColor;
  transition: background-color 0.24s ease;
}
.tt-navtoggle__bar::before,
.tt-navtoggle__bar::after {
  content: "";
  position: absolute;
  left: 0;
  width: 17px;
  height: 2px;
  background: currentColor;
  transition: transform 0.26s ease, top 0.26s ease;
}
.tt-navtoggle__bar::before { top: -5px; }
.tt-navtoggle__bar::after { top: 5px; }
.tt-navtoggle[aria-expanded="true"] .tt-navtoggle__bar { background: transparent; }
.tt-navtoggle[aria-expanded="true"] .tt-navtoggle__bar::before { top: 0; transform: rotate(45deg); }
.tt-navtoggle[aria-expanded="true"] .tt-navtoggle__bar::after { top: 0; transform: rotate(-45deg); }

/* 导航 */
.tt-nav {
  display: flex;
  align-items: center;
  gap: clamp(14px, 2.2vw, 28px);
}
.tt-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(12px, 1.9vw, 24px);
}
.tt-nav__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  padding: 8px 2px;
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--tt-silver);
  text-decoration: none;
  transition: color 0.2s ease;
}
.tt-nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 2px;
  height: 1px;
  background: var(--tt-orange);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.28s ease;
}
.tt-nav__link:hover { color: var(--tt-silver-2); }
.tt-nav__link:hover::after { transform: scaleX(1); }
.tt-nav__link[aria-current="page"] { color: var(--tt-silver-2); }
.tt-nav__link[aria-current="page"]::after { transform: scaleX(1); background: var(--tt-orange); }
.tt-nav__link[aria-current="page"]::before {
  content: "";
  width: 5px;
  height: 5px;
  margin-right: 7px;
  background: var(--tt-orange);
  clip-path: polygon(50% 0, 100% 50%, 50% 100%, 0 50%);
}

.tt-nav__quick {
  display: flex;
  align-items: center;
  gap: 7px;
  padding-left: 18px;
  border-left: 1px solid var(--tt-line);
}
.tt-quick {
  display: inline-flex;
  align-items: center;
  padding: 7px 12px;
  font-size: 12.5px;
  letter-spacing: 0.08em;
  color: var(--tt-silver);
  text-decoration: none;
  border: 1px solid var(--tt-line);
  border-radius: 14px 4px 14px 4px;
  background: rgba(198, 205, 214, 0.04);
  transition: color 0.22s ease, background-color 0.22s ease, border-color 0.22s ease;
}
.tt-quick:hover {
  color: var(--tt-space);
  background: var(--tt-orange);
  border-color: var(--tt-orange);
}

/* 推送细带 */
.tt-ticker {
  position: relative;
  z-index: 1;
  background: var(--tt-carbon);
  border-top: 1px solid var(--tt-line);
}
.tt-ticker__inner {
  display: flex;
  align-items: center;
  gap: 12px;
  padding-block: 9px;
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--tt-silver);
}
.tt-ticker__dot {
  flex: 0 0 auto;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--tt-sun);
  box-shadow: 0 0 0 3px rgba(232, 178, 58, 0.14);
}
.tt-ticker__text {
  flex: 1 1 auto;
  min-width: 0;
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
}
.tt-ticker__link {
  flex: 0 0 auto;
  color: var(--tt-orange);
  text-decoration: none;
  white-space: nowrap;
  border-bottom: 1px solid rgba(255, 90, 31, 0.42);
}
.tt-ticker__link:hover { color: var(--tt-sun); border-bottom-color: var(--tt-sun); }

/* ---------- 13. 页脚 ---------- */
.tt-footer {
  position: relative;
  overflow: hidden;
  background: var(--tt-carbon);
  color: var(--tt-silver);
  border-top: 1px solid var(--tt-line);
}
.tt-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(115deg, rgba(110, 139, 122, 0.10) 0 20%, transparent 20.1%),
    linear-gradient(295deg, rgba(255, 90, 31, 0.08) 0 14%, transparent 14.1%);
}
.tt-footer .tt-shell { position: relative; z-index: 1; }

.tt-footer__top {
  display: grid;
  grid-template-columns: minmax(230px, 1.05fr) minmax(0, 1.5fr) minmax(250px, 1fr);
  gap: clamp(26px, 4vw, 58px);
  padding-block: clamp(40px, 6vw, 74px) clamp(32px, 4vw, 50px);
}

.tt-footer__brand { display: flex; flex-direction: column; gap: 10px; }
.tt-footer__mark {
  width: 30px;
  height: 30px;
  border: 1px solid var(--tt-line-strong);
  border-radius: 10px 3px 10px 3px;
  background:
    linear-gradient(135deg, rgba(255, 90, 31, 0.22), transparent 60%),
    rgba(198, 205, 214, 0.06);
}
.tt-footer__lockup {
  font-size: 22px;
  font-weight: 900;
  letter-spacing: -0.01em;
  color: var(--tt-silver-2);
}
.tt-footer__suffix {
  font-size: 10.5px;
  letter-spacing: 0.14em;
  color: var(--tt-mist);
  max-width: 30ch;
}
.tt-footer__tagline {
  margin-top: 6px;
  max-width: 22ch;
  font-size: 15px;
  line-height: 1.7;
  color: var(--tt-silver);
}

.tt-footer__cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px 24px;
}
.tt-footer__title {
  margin-bottom: 12px;
  font-size: 11.5px;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--tt-mist);
}
.tt-footer__list { display: flex; flex-direction: column; gap: 2px; }
.tt-footer__link {
  display: inline-block;
  padding: 5px 0;
  font-size: 14.5px;
  color: var(--tt-silver);
  text-decoration: none;
  transition: color 0.2s ease, transform 0.2s ease;
}
.tt-footer__link:hover { color: var(--tt-orange); transform: translateX(3px); }

.tt-footer__contact { display: flex; flex-direction: column; gap: 10px; }
.tt-footer__line {
  max-width: 34ch;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--tt-silver);
}
.tt-footer__line--dim { color: var(--tt-mist); letter-spacing: 0.04em; }

.tt-copy {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
}
.tt-copy__value {
  font-family: var(--tt-font-num);
  font-size: 13.5px;
  letter-spacing: 0.04em;
  color: var(--tt-silver-2);
  word-break: break-all;
}
.tt-copy__btn {
  padding: 5px 12px;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--tt-silver);
  background: rgba(198, 205, 214, 0.05);
  border: 1px solid var(--tt-line-strong);
  border-radius: 12px 3px 12px 3px;
  cursor: pointer;
  transition: color 0.2s ease, border-color 0.2s ease, background-color 0.2s ease;
}
.tt-copy__btn:hover { color: var(--tt-orange); border-color: var(--tt-orange); }
.tt-copy__btn[data-state="done"] {
  color: var(--tt-space);
  background: var(--tt-sun);
  border-color: var(--tt-sun);
}

.tt-footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 26px;
  padding-block: 20px 28px;
  border-top: 1px solid var(--tt-line);
}
.tt-footer__legal {
  margin: 0;
  max-width: none;
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--tt-mist);
}

/* ---------- 14. 脚本注入元素 ---------- */
.tt-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 90;
  width: 100%;
  height: 2px;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--tt-orange), var(--tt-sun));
  pointer-events: none;
}
.tt-totop {
  position: fixed;
  right: clamp(14px, 3vw, 30px);
  bottom: clamp(14px, 3vw, 30px);
  z-index: 70;
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  color: var(--tt-silver-2);
  background: var(--tt-carbon);
  border: 1px solid var(--tt-line-strong);
  border-radius: 14px 4px 14px 4px;
  font-size: 17px;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity 0.26s ease, transform 0.26s ease, visibility 0.26s, border-color 0.2s ease, color 0.2s ease;
}
.tt-totop[data-show="true"] { opacity: 1; visibility: visible; transform: translateY(0); }
.tt-totop:hover { border-color: var(--tt-orange); color: var(--tt-orange); }

/* ---------- 15. 显影 ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.42s ease-out, transform 0.42s ease-out;
}
[data-reveal].is-on { opacity: 1; transform: none; }

/* ---------- 16. 响应式 ---------- */
@media (max-width: 1180px) {
  .tt-nav__quick { display: none; }
}

@media (max-width: 1024px) {
  .tt-footer__top {
    grid-template-columns: minmax(220px, 1fr) minmax(0, 1.4fr);
  }
  .tt-footer__contact { grid-column: 1 / -1; }
  .tt-footer__line { max-width: 46ch; }
}

@media (max-width: 920px) {
  body { font-size: 16.5px; }

  .tt-navtoggle { display: inline-flex; }

  .tt-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: block;
    background: var(--tt-carbon);
    border-top: 1px solid var(--tt-line);
    border-bottom: 1px solid var(--tt-line);
    box-shadow: 0 26px 44px -22px rgba(0, 0, 0, 0.78);
    max-height: 0;
    overflow: hidden;
    visibility: hidden;
    padding: 0 var(--tt-gutter);
    transition: max-height 0.4s cubic-bezier(0.2, 0.7, 0.2, 1), padding 0.4s ease, visibility 0.4s;
  }
  .tt-nav[data-open="true"] {
    max-height: min(78vh, 620px);
    overflow-y: auto;
    visibility: visible;
    padding-block: 8px 26px;
  }
  .tt-nav__list { flex-direction: column; align-items: stretch; gap: 0; }
  .tt-nav__link {
    padding: 14px 0;
    font-size: 16px;
    border-bottom: 1px solid var(--tt-line);
  }
  .tt-nav__link::after { display: none; }
  .tt-nav__link[aria-current="page"] { color: var(--tt-orange); }
  .tt-nav__quick {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 18px;
    padding: 18px 0 0;
    border-left: 0;
    border-top: 1px dashed var(--tt-line);
  }
  .tt-ticker__inner { font-size: 12px; }
}

@media (max-width: 760px) {
  .tt-lede { max-width: 100%; }
  .tt-footer__cols { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .tt-footer__bottom { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 560px) {
  .tt-brand__sub { display: none; }
  .tt-navtoggle__label { display: none; }
  .tt-navtoggle { padding: 10px 12px; }
  .tt-ticker__text { font-size: 11.5px; }
  .tt-footer__cols { grid-template-columns: minmax(0, 1fr); gap: 22px; }
  .tt-footer__top { padding-block: 38px 30px; }
  .tt-footer__line,
  .tt-copy__value { max-width: 100%; }
}

/* ---------- 17. 可访问性与动效偏好 ---------- */
@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;
  }
  [data-reveal] { opacity: 1; transform: none; }
  .tt-totop { transform: none; }
}