/* ==========================================================================
   IMTOKEN钱包 · 共享外壳样式 /assets/site.css
   深空底 + 电光青/琥珀橙语义色 + 纵向长卷章节体系
   ========================================================================== */

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

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

body {
  margin: 0;
  background: var(--vt-base);
  color: var(--vt-text);
  font-family: var(--vt-font-body);
  font-size: 16px;
  line-height: 1.75;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6, p, ul, ol, figure, blockquote { margin: 0; padding: 0; }
ul, ol { list-style: none; }
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
table { width: 100%; border-collapse: collapse; }
hr { border: 0; }

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

::selection { background: rgba(59, 224, 210, .28); color: #ffffff; }

/* 2. 变量 ---------------------------------------------------------------- */
:root {
  --vt-base: #05070C;
  --vt-raised: #0B1220;
  --vt-grid: #1C2738;
  --vt-strong: #2B3A50;
  --vt-text: #E8EFF7;
  --vt-muted: #93A2B5;
  --vt-confirmed: #3BE0D2;
  --vt-confirmed-dim: #14867F;
  --vt-pending: #FFAE47;
  --vt-pending-dim: #A6601B;
  --vt-paper: #F1EDE3;
  --vt-paper-ink: #1A1712;

  --vt-max: 1280px;
  --vt-prose: 720px;

  --vt-font-display: "Helvetica Neue", "Arial Narrow", "Noto Sans SC",
    "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --vt-font-body: "Noto Sans SC", "Source Han Sans SC", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --vt-font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace,
    SFMono-Regular, Menlo, Consolas, "Courier New", monospace;

  --vt-gap-chapter: clamp(64px, 10vw, 128px);
}

/* 3. 基础排版 ------------------------------------------------------------ */
h1, h2, h3, h4 {
  font-family: var(--vt-font-display);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.015em;
  color: var(--vt-text);
}

h1 { font-size: clamp(32px, 5vw, 58px); }
h2 { font-size: clamp(24px, 3.2vw, 36px); }
h3 { font-size: clamp(19px, 2.2vw, 24px); }
h4 { font-size: 16px; letter-spacing: .04em; }

p { text-wrap: pretty; }
strong { color: var(--vt-text); font-weight: 700; }

/* 4. 跳转链接 ------------------------------------------------------------ */
.vt-skip {
  position: absolute;
  left: 16px;
  top: -80px;
  z-index: 200;
  padding: 12px 22px;
  background: var(--vt-confirmed);
  color: #04211F;
  font-family: var(--vt-font-mono);
  font-size: 13px;
  letter-spacing: .08em;
  transition: top .2s ease;
}
.vt-skip:focus { top: 16px; }

/* 5. 报头 ---------------------------------------------------------------- */
.vt-header {
  position: relative;
  z-index: 60;
  background: var(--vt-base);
  border-bottom: 1px solid var(--vt-grid);
}

.vt-statusbar {
  background: #070B14;
  border-bottom: 1px solid var(--vt-grid);
}

.vt-statusbar__inner {
  display: flex;
  justify-content: space-between;
  gap: 28px;
  max-width: var(--vt-max);
  margin: 0 auto;
  padding: 9px 24px;
  overflow-x: auto;
  scrollbar-width: none;
  font-family: var(--vt-font-mono);
  font-size: 11px;
  letter-spacing: .07em;
  color: var(--vt-muted);
  white-space: nowrap;
}
.vt-statusbar__inner::-webkit-scrollbar { display: none; }

.vt-statusbar__item { display: inline-flex; align-items: center; gap: 8px; }

.vt-dot {
  flex: none;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--vt-strong);
}
.vt-dot--confirmed { background: var(--vt-confirmed); box-shadow: 0 0 0 3px rgba(59, 224, 210, .14); }
.vt-dot--pending { background: var(--vt-pending); box-shadow: 0 0 0 3px rgba(255, 174, 71, .16); }

.vt-masthead {
  position: relative;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 24px;
  max-width: var(--vt-max);
  margin: 0 auto;
  padding: 28px 24px 22px;
}

.vt-masthead__note,
.vt-masthead__legend {
  font-family: var(--vt-font-mono);
  font-size: 11px;
  letter-spacing: .09em;
  color: var(--vt-muted);
}
.vt-masthead__note { justify-self: start; }
.vt-masthead__legend { justify-self: end; text-align: right; }

.vt-masthead__brand {
  display: inline-flex;
  align-items: baseline;
  gap: .12em;
  justify-self: center;
}
.vt-masthead__brand-en {
  font-family: var(--vt-font-display);
  font-weight: 800;
  font-size: clamp(30px, 5.4vw, 60px);
  line-height: 1;
  letter-spacing: -0.02em;
  text-transform: uppercase;
  color: var(--vt-text);
  transition: color .25s ease;
}
.vt-masthead__brand-cn {
  font-family: var(--vt-font-display);
  font-weight: 800;
  font-size: clamp(15px, 2.2vw, 25px);
  letter-spacing: .06em;
  color: var(--vt-confirmed);
}
.vt-masthead__brand:hover .vt-masthead__brand-en { color: var(--vt-confirmed); }

.vt-navtoggle {
  display: none;
  position: absolute;
  right: 18px;
  top: 50%;
  transform: translateY(-50%);
  align-items: center;
  gap: 9px;
  padding: 9px 12px;
  border: 1px solid var(--vt-strong);
  font-family: var(--vt-font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--vt-muted);
  transition: border-color .2s ease, color .2s ease;
}
.vt-navtoggle__bars,
.vt-navtoggle__bars::before,
.vt-navtoggle__bars::after {
  display: block;
  width: 16px;
  height: 1px;
  background: currentColor;
}
.vt-navtoggle__bars { position: relative; }
.vt-navtoggle__bars::before,
.vt-navtoggle__bars::after { content: ""; position: absolute; left: 0; }
.vt-navtoggle__bars::before { top: -5px; }
.vt-navtoggle__bars::after { top: 5px; }
.vt-navtoggle[aria-expanded="true"] {
  border-color: var(--vt-pending);
  color: var(--vt-pending);
}

.vt-nav {
  background: var(--vt-raised);
  border-top: 1px solid var(--vt-grid);
}

.vt-nav__list {
  position: relative;
  display: flex;
  justify-content: center;
  max-width: var(--vt-max);
  margin: 0 auto;
  padding: 0 24px;
}

.vt-nav__list::before {
  content: "";
  position: absolute;
  left: 24px;
  right: 24px;
  top: 21px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--vt-grid) 10%, var(--vt-grid) 90%, transparent);
}

.vt-nav__list::after {
  content: "";
  position: absolute;
  left: 24px;
  right: 24px;
  top: 12px;
  height: 6px;
  background-image: repeating-linear-gradient(90deg, var(--vt-grid) 0 1px, transparent 1px 26px);
  opacity: .8;
  pointer-events: none;
}

.vt-nav__item { position: relative; flex: 0 0 auto; }

.vt-nav__link {
  position: relative;
  display: block;
  padding: 32px 20px 16px;
  font-family: var(--vt-font-display);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .16em;
  color: var(--vt-muted);
  transition: color .22s ease;
}

.vt-nav__link::before {
  content: "";
  position: absolute;
  top: 17px;
  left: 50%;
  transform: translateX(-50%);
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--vt-base);
  border: 1px solid var(--vt-strong);
  transition: background .22s ease, border-color .22s ease, box-shadow .22s ease;
}

.vt-nav__link:hover { color: var(--vt-text); }
.vt-nav__link:hover::before { border-color: var(--vt-confirmed); }

.vt-nav__link[aria-current="page"] { color: var(--vt-confirmed); }
.vt-nav__link[aria-current="page"]::before {
  background: var(--vt-confirmed);
  border-color: var(--vt-confirmed);
  box-shadow: 0 0 0 4px rgba(59, 224, 210, .16);
}

/* 6. 页脚 ---------------------------------------------------------------- */
.vt-footer {
  position: relative;
  background: #04060A;
  border-top: 1px solid var(--vt-grid);
}

.vt-footer__band {
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--vt-confirmed-dim) 18%, var(--vt-confirmed) 46%, var(--vt-pending-dim) 76%, transparent);
  opacity: .75;
}

.vt-footer__inner {
  max-width: var(--vt-max);
  margin: 0 auto;
  padding: clamp(48px, 7vw, 88px) 24px clamp(32px, 4vw, 56px);
  display: grid;
  grid-template-columns: 1fr;
  gap: 48px;
}

.vt-footer__brandname {
  font-family: var(--vt-font-display);
  font-size: 22px;
  font-weight: 800;
  letter-spacing: .04em;
  color: var(--vt-text);
}
.vt-footer__brandnote {
  margin-top: 8px;
  font-family: var(--vt-font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--vt-muted);
}
.vt-footer__legend {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}
.vt-legend-key {
  display: inline-flex;
  align-items: center;
  padding: 4px 10px;
  font-family: var(--vt-font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  border: 1px solid;
}
.vt-legend-key--confirmed {
  color: var(--vt-confirmed);
  border-color: rgba(59, 224, 210, .4);
  background: rgba(59, 224, 210, .07);
}
.vt-legend-key--pending {
  color: var(--vt-pending);
  border-color: rgba(255, 174, 71, .4);
  background: rgba(255, 174, 71, .08);
}

.vt-footer__cols {
  display: grid;
  grid-template-columns: 1fr;
  gap: 36px;
}

.vt-footer__coltitle {
  font-family: var(--vt-font-display);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .18em;
  color: var(--vt-muted);
  padding-bottom: 12px;
  border-bottom: 1px solid var(--vt-grid);
}

.vt-footer__list { margin-top: 14px; }

.vt-footer__item { margin-bottom: 9px; }

.vt-footer__link {
  font-size: 14px;
  color: var(--vt-text);
  border-bottom: 1px solid transparent;
  transition: color .2s ease, border-color .2s ease;
}
.vt-footer__link:hover { color: var(--vt-confirmed); border-color: var(--vt-confirmed); }

.vt-footer__text {
  font-family: var(--vt-font-mono);
  font-size: 12px;
  letter-spacing: .02em;
  color: var(--vt-muted);
  line-height: 1.7;
}

.vt-footer__legal {
  grid-column: 1 / -1;
  padding-top: 28px;
  border-top: 1px solid var(--vt-grid);
}
.vt-footer__addr {
  font-size: 14px;
  color: var(--vt-text);
}
.vt-footer__update {
  margin-top: 10px;
  max-width: 62ch;
  font-size: 13px;
  color: var(--vt-muted);
}

.vt-footer__base {
  max-width: var(--vt-max);
  margin: 0 auto;
  padding: 18px 24px 32px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 26px;
  align-items: center;
  justify-content: space-between;
  border-top: 1px solid var(--vt-grid);
}
.vt-footer__baseline,
.vt-footer__icp {
  font-family: var(--vt-font-mono);
  font-size: 11px;
  letter-spacing: .06em;
  color: var(--vt-muted);
}
.vt-footer__icp { color: var(--vt-pending); }

/* 7. 按钮 ---------------------------------------------------------------- */
.vt-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 26px;
  font-family: var(--vt-font-display);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .16em;
  color: var(--vt-text);
  background: transparent;
  border: 1px solid var(--vt-strong);
  transition: color .22s ease, border-color .22s ease, background .22s ease;
}
.vt-btn:hover { color: var(--vt-confirmed); border-color: var(--vt-confirmed); }

.vt-btn--primary {
  color: #04211F;
  background: var(--vt-confirmed);
  border-color: var(--vt-confirmed);
}
.vt-btn--primary:hover { color: #04211F; background: #66EBDF; border-color: #66EBDF; }

.vt-btn--warn {
  color: var(--vt-pending);
  border-color: rgba(255, 174, 71, .5);
}
.vt-btn--warn:hover {
  color: #1A1004;
  background: var(--vt-pending);
  border-color: var(--vt-pending);
}

/* 8. 面包屑 -------------------------------------------------------------- */
.vt-crumbs {
  border-bottom: 1px solid var(--vt-grid);
  background: var(--vt-base);
}
.vt-crumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  max-width: var(--vt-max);
  margin: 0 auto;
  padding: 16px 24px;
  font-family: var(--vt-font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--vt-muted);
}
.vt-crumbs__item { display: inline-flex; align-items: center; gap: 10px; }
.vt-crumbs__sep { color: var(--vt-strong); }
.vt-crumbs__link { transition: color .2s ease; }
.vt-crumbs__link:hover { color: var(--vt-confirmed); }

/* 9. 布局容器 ------------------------------------------------------------ */
.vt-shell {
  width: 100%;
  max-width: var(--vt-max);
  margin: 0 auto;
  padding: 0 24px;
}
.vt-shell--narrow { max-width: 960px; }

.vt-prose {
  max-width: var(--vt-prose);
  font-size: 17px;
  line-height: 1.78;
  color: var(--vt-text);
}
.vt-prose p { margin-bottom: 18px; }
.vt-prose p:last-child { margin-bottom: 0; }
.vt-prose h2 { margin: 42px 0 14px; font-size: clamp(22px, 2.6vw, 30px); }
.vt-prose h3 { margin: 32px 0 12px; }
.vt-prose ul { margin: 0 0 18px; }
.vt-prose li {
  position: relative;
  padding-left: 20px;
  margin-bottom: 8px;
}
.vt-prose li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 8px;
  height: 1px;
  background: var(--vt-confirmed);
}

.vt-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 4vw, 56px);
}

/* 10. 章节长卷 ----------------------------------------------------------- */
.vt-chapter {
  position: relative;
  padding: var(--vt-gap-chapter) 0;
  border-top: 1px solid var(--vt-grid);
}
.vt-chapter:first-of-type { border-top: 0; }

.vt-chapter__num {
  display: block;
  font-family: var(--vt-font-mono);
  font-size: 12px;
  letter-spacing: .26em;
  color: var(--vt-confirmed);
}
.vt-chapter__title {
  margin-top: 12px;
  font-family: var(--vt-font-display);
  font-size: clamp(26px, 3.6vw, 38px);
  font-weight: 800;
  letter-spacing: -0.012em;
  line-height: 1.2;
}
.vt-chapter__lede {
  max-width: 38em;
  margin-top: 14px;
  font-size: 17px;
  color: var(--vt-muted);
}

.vt-band {
  height: 2px;
  border: 0;
  background: linear-gradient(90deg, var(--vt-confirmed-dim), var(--vt-confirmed) 24%, var(--vt-grid) 68%, transparent);
}

.vt-tickscale {
  height: 10px;
  border-bottom: 1px solid var(--vt-grid);
  background-image: repeating-linear-gradient(90deg, var(--vt-grid) 0 1px, transparent 1px 28px);
}

.vt-divider {
  height: 1px;
  background: var(--vt-grid);
}

/* 11. 参数与状态组件 ----------------------------------------------------- */
.vt-kv { border-top: 1px solid var(--vt-grid); }

.vt-kv__row {
  display: grid;
  grid-template-columns: minmax(110px, 190px) 1fr;
  gap: 8px 20px;
  align-items: baseline;
  padding: 14px 0;
  border-bottom: 1px solid var(--vt-grid);
}

.vt-kv__key {
  font-family: var(--vt-font-mono);
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--vt-confirmed);
}
.vt-kv__note {
  font-size: 15px;
  color: var(--vt-muted);
}

.vt-mono {
  font-family: var(--vt-font-mono);
  font-size: .95em;
  letter-spacing: .02em;
}

.vt-hl {
  font-family: var(--vt-font-mono);
  color: var(--vt-confirmed);
  background: rgba(59, 224, 210, .08);
  padding: .04em .34em;
}
.vt-hl--pending {
  color: var(--vt-pending);
  background: rgba(255, 174, 71, .1);
}

.vt-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  font-family: var(--vt-font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  border: 1px solid;
}
.vt-badge--confirmed {
  color: var(--vt-confirmed);
  border-color: rgba(59, 224, 210, .45);
  background: rgba(59, 224, 210, .08);
}
.vt-badge--pending {
  color: var(--vt-pending);
  border-color: rgba(255, 174, 71, .45);
  background: rgba(255, 174, 71, .09);
}

.vt-note {
  padding: 10px 0 10px 16px;
  border-left: 2px solid var(--vt-pending);
  font-size: 15px;
  color: var(--vt-muted);
}

.vt-paper {
  background: var(--vt-paper);
  color: var(--vt-paper-ink);
  padding: clamp(22px, 3vw, 34px);
  border: 1px solid #D7D0C0;
  box-shadow: 6px 6px 0 rgba(241, 237, 227, .07), 12px 12px 0 rgba(241, 237, 227, .03);
}
.vt-paper h2,
.vt-paper h3 { color: var(--vt-paper-ink); }
.vt-paper p { font-size: 15px; line-height: 1.7; }
.vt-paper .vt-mono { color: #4A4234; }

/* 12. 图片容器 ----------------------------------------------------------- */
.vt-figure { margin: 0; }

.vt-figure__frame {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: var(--vt-raised);
  border: 1px solid var(--vt-strong);
}
.vt-figure__frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  box-shadow: inset 0 0 0 1px rgba(5, 7, 12, .55);
}
.vt-figure__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.85) contrast(1.05);
}
.vt-figure__cap {
  margin-top: 12px;
  font-family: var(--vt-font-mono);
  font-size: 12px;
  letter-spacing: .03em;
  color: var(--vt-muted);
}
.vt-figure--wide .vt-figure__frame { aspect-ratio: 21 / 9; }
.vt-figure--tall .vt-figure__frame { aspect-ratio: 4 / 5; }

/* 13. 章节索引 / 进度 / 返回顶部 ---------------------------------------- */
.vt-rail {
  display: none;
  position: fixed;
  right: 26px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 45;
  width: 152px;
}
.vt-rail__title {
  font-family: var(--vt-font-mono);
  font-size: 10px;
  letter-spacing: .22em;
  color: var(--vt-muted);
  padding-bottom: 10px;
  border-bottom: 1px solid var(--vt-grid);
}
.vt-rail__list { border-left: 1px solid var(--vt-grid); }
.vt-rail__item { display: block; }
.vt-rail__btn {
  display: flex;
  align-items: baseline;
  gap: 8px;
  width: 100%;
  padding: 7px 0 7px 12px;
  text-align: left;
  border-left: 1px solid transparent;
  margin-left: -1px;
  transition: border-color .2s ease, color .2s ease;
}
.vt-rail__num {
  font-family: var(--vt-font-mono);
  font-size: 10px;
  color: var(--vt-strong);
}
.vt-rail__label {
  font-size: 12px;
  line-height: 1.5;
  color: var(--vt-muted);
}
.vt-rail__btn:hover .vt-rail__label { color: var(--vt-text); }
.vt-rail__btn.is-active { border-left-color: var(--vt-confirmed); }
.vt-rail__btn.is-active .vt-rail__num { color: var(--vt-confirmed); }
.vt-rail__btn.is-active .vt-rail__label { color: var(--vt-confirmed); }

.vt-progress {
  position: fixed;
  left: 0;
  right: 0;
  top: 0;
  height: 2px;
  z-index: 90;
  background: rgba(28, 39, 56, .5);
  pointer-events: none;
}
.vt-progress__bar {
  display: block;
  height: 100%;
  width: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--vt-confirmed-dim), var(--vt-confirmed) 70%, var(--vt-pending));
}

.vt-totop {
  position: fixed;
  right: 22px;
  bottom: 24px;
  z-index: 55;
  padding: 11px 16px;
  font-family: var(--vt-font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--vt-text);
  background: rgba(11, 18, 32, .94);
  border: 1px solid var(--vt-strong);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity .25s ease, transform .25s ease, visibility .25s ease,
    border-color .25s ease, color .25s ease;
}
.vt-totop[data-visible] {
  opacity: 1;
  visibility: visible;
  transform: none;
}
.vt-totop:hover { color: var(--vt-confirmed); border-color: var(--vt-confirmed); }

.vt-reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity .6s ease, transform .6s cubic-bezier(.2, .7, .3, 1);
}
.vt-reveal.is-in {
  opacity: 1;
  transform: none;
}

/* 14. 响应式 ------------------------------------------------------------- */
@media (min-width: 640px) {
  .vt-footer__cols { grid-template-columns: repeat(2, 1fr); }
  .vt-kv__row { grid-template-columns: minmax(140px, 200px) 1fr; }
}

@media (min-width: 900px) {
  .vt-footer__inner { grid-template-columns: 1fr 2.6fr; }
  .vt-footer__cols { grid-template-columns: repeat(4, 1fr); gap: 28px; }
  .vt-grid--2-7-3 { grid-template-columns: 2fr 7fr 3fr; }
  .vt-grid--3-6-3 { grid-template-columns: 3fr 6fr 3fr; }
}

@media (max-width: 899px) {
  .vt-masthead {
    grid-template-columns: 1fr;
    padding: 22px 74px 18px;
  }
  .vt-masthead__note,
  .vt-masthead__legend { display: none; }
  .vt-navtoggle { display: inline-flex; }

  .vt-nav { display: none; }
  .vt-nav[data-open] { display: block; }

  .vt-nav__list {
    flex-direction: column;
    padding: 6px 20px 20px;
  }
  .vt-nav__list::before,
  .vt-nav__list::after { display: none; }

  .vt-nav__item { width: 100%; }

  .vt-nav__link {
    padding: 14px 0 14px 26px;
    border-bottom: 1px solid var(--vt-grid);
    font-size: 14px;
  }
  .vt-nav__link::before {
    top: 50%;
    left: 4px;
    transform: translateY(-50%);
  }
}

@media (min-width: 1440px) {
  .vt-rail { display: block; }
}

@media (max-width: 400px) {
  .vt-statusbar__inner { font-size: 10px; gap: 18px; }
  .vt-totop { right: 14px; bottom: 14px; }
}

/* 15. 无障碍与动效降级 --------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
  .vt-reveal { opacity: 1; transform: none; }
  .vt-totop { transform: none; }
}