/* =========================================================
   凤凰体育主站 / site.css
   画框导航 · 展览画册 · 深空蓝墨数据作战室
   ========================================================= */

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

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

body {
  margin: 0;
  min-height: 100vh;
}

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

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

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

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

a { color: inherit; }

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

address { font-style: normal; }

/* ---------- 2. TOKENS ---------- */
:root {
  --ink: #081222;        /* 深空蓝墨 */
  --ink-2: #12203A;      /* 深空蓝阶 */
  --bone: #F3EEE3;       /* 骨白 */
  --flame: #F4531F;      /* 凤凰焰火橙 */
  --copper: #C99A46;     /* 铜金 */
  --jade: #2FA37A;       /* 云南高原翠绿 */
  --crimson: #C0422E;    /* 绛霞红 */
  --mist: #7F90A8;       /* 雾蓝灰 */
  --ember: #3A4252;      /* 余烬灰 */

  --rail-w: 236px;
  --topbar-h: 56px;

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

  --pad-x: clamp(18px, 3.4vw, 56px);
  --gap: clamp(16px, 2vw, 28px);
  --ease: cubic-bezier(.22, .7, .2, 1);
}

::selection { background: var(--flame); color: var(--ink); }

/* ---------- 3. BASE & 中文排版 ---------- */
body {
  background-color: var(--ink);
  background-image:
    linear-gradient(rgba(127, 144, 168, .055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(127, 144, 168, .055) 1px, transparent 1px);
  background-size: 72px 72px, 72px 72px;
  color: var(--bone);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.8;
  letter-spacing: .01em;
  padding-top: var(--topbar-h);
  -webkit-font-smoothing: antialiased;
}

body.is-nav-open { overflow: hidden; }

@media (min-width: 1024px) {
  body { padding-left: var(--rail-w); }
}

h1, h2, h3, h4 {
  font-weight: 900;
  letter-spacing: -.025em;
  line-height: 1.15;
}

p { max-width: 72ch; }

a, button, [tabindex] { transition: color .2s var(--ease), background-color .2s var(--ease), border-color .2s var(--ease); }

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

.site-main { display: block; min-height: 60vh; }

/* ---------- 4. SKIP LINK ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 12px;
  z-index: 120;
  padding: 10px 16px;
  background: var(--bone);
  color: var(--ink);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .06em;
  text-decoration: none;
  border: 1px solid var(--flame);
  transform: translateY(-220%);
  transition: transform .2s var(--ease);
}

.skip-link:focus { transform: translateY(0); }

/* ---------- 5. 画框头部 ---------- */
.site-frame {
  position: fixed;
  z-index: 90;
  background: var(--ink);
  border-color: var(--ember);
}

.frame-top { display: none; }

/* --- 桌面：左侧竖向导轨 --- */
@media (min-width: 1024px) {
  .site-frame {
    top: 0;
    left: 0;
    bottom: 0;
    width: var(--rail-w);
    display: flex;
    flex-direction: column;
    padding: 24px 20px 20px;
    border-right: 1px solid var(--ember);
    background-image: linear-gradient(180deg, rgba(18, 32, 58, .95), rgba(8, 18, 34, 1));
  }

  .frame-top {
    display: flex;
    position: fixed;
    top: 0;
    left: var(--rail-w);
    right: 0;
    height: var(--topbar-h);
    z-index: 80;
    align-items: center;
    gap: 22px;
    padding: 0 var(--pad-x);
    background: rgba(8, 18, 34, .92);
    border-bottom: 1px solid var(--ember);
    backdrop-filter: blur(6px);
  }

  .frame-top__ticks {
    flex: 1;
    height: 10px;
    background-image: repeating-linear-gradient(90deg, var(--ember) 0 1px, transparent 1px 22px);
    -webkit-mask-image: linear-gradient(90deg, transparent, #000 10%, #000 90%, transparent);
    mask-image: linear-gradient(90deg, transparent, #000 10%, #000 90%, transparent);
  }

  .frame-top__meta {
    display: flex;
    align-items: center;
    gap: 16px;
  }

  .frame-rail {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-height: 0;
  }

  .frame-nav {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-height: 0;
    margin-top: 30px;
    overflow-y: auto;
  }

  .frame-rail__foot {
    margin-top: auto;
    padding-top: 20px;
  }

  .frame-cta { width: 100%; justify-content: center; }

  .nav-toggle { display: none; }
}

.frame-top__season,
.frame-top__meta .label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .22em;
}

.frame-top__season { color: var(--mist); text-transform: uppercase; }

/* --- 品牌 --- */
.brand {
  position: relative;
  display: block;
  padding-left: 14px;
  color: var(--bone);
  text-decoration: none;
}

.brand::before {
  content: "";
  position: absolute;
  left: 0;
  top: 3px;
  bottom: 3px;
  width: 3px;
  background: var(--flame);
}

.brand__mark {
  display: block;
  font-size: 20px;
  font-weight: 900;
  letter-spacing: -.02em;
  line-height: 1.25;
}

.brand__sub {
  display: block;
  margin-top: 7px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .26em;
  color: var(--mist);
}

.brand:hover .brand__mark { color: var(--flame); }

/* --- 导航 --- */
.frame-nav__list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.frame-nav__link {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 11px 12px;
  color: var(--bone);
  font-size: 14.5px;
  letter-spacing: .02em;
  text-decoration: none;
  border: 1px solid transparent;
}

.frame-nav__link::before {
  content: attr(data-index);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .12em;
  color: var(--mist);
}

.frame-nav__link:hover {
  background: rgba(243, 238, 227, .06);
  border-color: var(--ember);
}

.frame-nav__link[aria-current="page"] {
  background: var(--flame);
  border-color: var(--flame);
  color: var(--ink);
  font-weight: 700;
}

.frame-nav__link[aria-current="page"]::before { color: var(--ink); opacity: .7; }

/* --- 移动：顶部栏 + 抽屉 --- */
@media (max-width: 1023px) {
  .site-frame {
    top: 0;
    left: 0;
    right: 0;
    height: var(--topbar-h);
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 0 16px;
    background: rgba(8, 18, 34, .96);
    border-bottom: 1px solid var(--ember);
    backdrop-filter: blur(8px);
  }

  .frame-rail {
    display: flex;
    flex: 1;
    min-width: 0;
    align-items: center;
    justify-content: space-between;
  }

  .brand { padding-left: 12px; }

  .brand__mark { font-size: 17px; white-space: nowrap; }

  .brand__sub { display: none; }

  .frame-nav {
    position: fixed;
    top: var(--topbar-h);
    left: 0;
    right: 0;
    max-height: 0;
    overflow: hidden;
    padding: 0 16px;
    opacity: 0;
    visibility: hidden;
    background: linear-gradient(180deg, #0E1B30, var(--ink));
    border-bottom: 1px solid var(--ember);
    transition: max-height .34s var(--ease), opacity .22s var(--ease), visibility .22s;
  }

  [data-frame][data-open="true"] .frame-nav {
    max-height: 78vh;
    overflow-y: auto;
    padding: 12px 16px 24px;
    opacity: 1;
    visibility: visible;
  }

  .frame-nav__link {
    padding: 15px 10px;
    font-size: 16px;
    border-bottom: 1px solid rgba(58, 66, 82, .55);
  }

  .frame-nav__link[aria-current="page"] { border-color: var(--flame); }

  .frame-rail__foot { margin-top: 20px; }

  .frame-cta { width: 100%; justify-content: center; }
}

/* --- 汉堡按钮 --- */
.nav-toggle {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 9px 12px;
  border: 1px solid var(--ember);
  color: var(--bone);
  font-size: 12px;
  letter-spacing: .22em;
  cursor: pointer;
}

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

.nav-toggle__bars {
  position: relative;
  display: block;
  width: 18px;
  height: 2px;
  background: currentColor;
  transition: background-color .2s var(--ease);
}

.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: currentColor;
  transition: transform .25s var(--ease), top .25s var(--ease);
}

.nav-toggle__bars::before { top: -6px; }
.nav-toggle__bars::after { top: 6px; }

[data-frame][data-open="true"] .nav-toggle__bars { background: transparent; }
[data-frame][data-open="true"] .nav-toggle__bars::before { top: 0; transform: rotate(45deg); }
[data-frame][data-open="true"] .nav-toggle__bars::after { top: 0; transform: rotate(-45deg); }

@media (min-width: 1024px) {
  .nav-toggle { display: none; }
}

/* ---------- 6. 页脚 ---------- */
.site-foot {
  position: relative;
  margin-top: clamp(56px, 8vw, 120px);
  background-image: linear-gradient(180deg, rgba(18, 32, 58, .92), var(--ink) 70%);
  border-top: 1px solid var(--ember);
  color: var(--mist);
}

.site-foot__ruler {
  height: 12px;
  background-image: repeating-linear-gradient(90deg, var(--ember) 0 1px, transparent 1px 18px);
  opacity: .85;
  border-bottom: 1px solid rgba(58, 66, 82, .5);
}

.site-foot__inner {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr) minmax(0, 1.1fr);
  gap: clamp(26px, 3.4vw, 56px);
  padding-top: clamp(44px, 5vw, 78px);
  padding-bottom: clamp(40px, 5vw, 72px);
}

.foot-col__title {
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  letter-spacing: .3em;
  color: var(--copper);
  text-transform: uppercase;
  line-height: 1.4;
}

.foot-brand__mark {
  font-size: 22px;
  font-weight: 900;
  letter-spacing: -.02em;
  color: var(--bone);
  line-height: 1.3;
}

.foot-brand__desc {
  margin-top: 12px;
  max-width: 42ch;
  font-size: 14px;
  line-height: 1.85;
  color: var(--mist);
}

.foot-brand__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 18px;
}

.foot-nav__list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 9px 20px;
}

.foot-nav__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 2px 0;
  font-size: 14px;
  color: var(--bone);
  text-decoration: none;
}

.foot-nav__link::before {
  content: "";
  width: 10px;
  height: 1px;
  background: var(--copper);
  flex: none;
  transform: translateY(-4px);
}

.foot-nav__link:hover { color: var(--flame); }

.foot-contact__list { display: flex; flex-direction: column; }

.foot-contact__item {
  display: grid;
  grid-template-columns: 58px minmax(0, 1fr);
  gap: 10px;
  padding: 10px 0;
  border-bottom: 1px dashed rgba(58, 66, 82, .9);
  font-size: 13.5px;
}

.foot-contact__key {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .24em;
  color: var(--copper);
  padding-top: 5px;
}

.foot-contact__val { color: var(--bone); word-break: break-word; }

.foot-contact__note {
  margin-top: 14px;
  font-size: 12.5px;
  line-height: 1.8;
  color: var(--mist);
}

.site-foot__legal {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 10px 26px;
  padding: 18px var(--pad-x);
  border-top: 1px solid var(--ember);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--mist);
}

@media (max-width: 900px) {
  .site-foot__inner { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .foot-brand { grid-column: 1 / -1; }
}

@media (max-width: 600px) {
  .site-foot__inner { grid-template-columns: minmax(0, 1fr); }
  .foot-nav__list { grid-template-columns: minmax(0, 1fr); }
  .site-foot__legal { justify-content: flex-start; }
}

/* ---------- 7. 通用按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 12px 20px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .04em;
  line-height: 1.3;
  text-decoration: none;
  color: var(--bone);
  background: transparent;
  border: 1px solid var(--ember);
  cursor: pointer;
}

.btn:hover { background: rgba(243, 238, 227, .08); border-color: var(--bone); }

.btn--primary {
  background: var(--flame);
  border-color: var(--flame);
  color: var(--ink);
}

.btn--primary:hover { background: #FF6A34; border-color: #FF6A34; color: var(--ink); }

.btn--gold {
  border-color: var(--copper);
  color: var(--copper);
}

.btn--gold:hover { background: rgba(201, 154, 70, .14); border-color: var(--copper); }

.btn--ghost { border-color: rgba(127, 144, 168, .5); color: var(--mist); }

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

/* ---------- 8. 容器 / 网格 / 章节 ---------- */
.container {
  width: 100%;
  max-width: 1320px;
  margin-inline: auto;
  padding-inline: var(--pad-x);
}

.grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gap);
}

.col-3 { grid-column: span 3; }
.col-4 { grid-column: span 4; }
.col-6 { grid-column: span 6; }
.col-8 { grid-column: span 8; }
.col-12 { grid-column: span 12; }

.drop-1 { margin-top: clamp(0px, 3vw, 40px); }
.drop-2 { margin-top: clamp(0px, 6vw, 88px); }

@media (max-width: 1023px) {
  .grid { grid-template-columns: repeat(6, minmax(0, 1fr)); }
  .col-3, .col-4 { grid-column: span 3; }
  .col-6, .col-8 { grid-column: span 6; }
}

@media (max-width: 640px) {
  .grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .col-3, .col-4, .col-6, .col-8 { grid-column: 1 / -1; }
  .drop-1, .drop-2 { margin-top: 0; }
}

.section { padding-block: clamp(48px, 6.5vw, 108px); }

.section__head {
  position: relative;
  display: grid;
  gap: 12px;
  margin-bottom: clamp(24px, 3vw, 46px);
  padding-left: clamp(0px, 1.6vw, 26px);
  border-left: 1px solid var(--ember);
}

.section__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .3em;
  color: var(--flame);
}

.section__title {
  font-size: clamp(28px, 4.4vw, 52px);
  font-weight: 900;
  letter-spacing: -.025em;
  line-height: 1.12;
  color: var(--bone);
}

.section__note {
  max-width: 58ch;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--mist);
}

.page-head {
  position: relative;
  padding-top: clamp(36px, 5vw, 74px);
  padding-bottom: clamp(22px, 3vw, 44px);
}

.page-head__eyebrow {
  display: block;
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .3em;
  color: var(--flame);
  text-transform: uppercase;
}

.page-head__title {
  font-size: clamp(32px, 5.6vw, 64px);
  font-weight: 900;
  letter-spacing: -.025em;
  line-height: 1.1;
  color: var(--bone);
}

.page-head__lead {
  margin-top: 16px;
  max-width: 62ch;
  font-size: 16.5px;
  line-height: 1.85;
  color: var(--mist);
}

/* ---------- 9. 标签 / 面板 / 数据 ---------- */
.label {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 9px;
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.5;
  letter-spacing: .2em;
  color: var(--mist);
  border: 1px solid var(--ember);
  background: rgba(8, 18, 34, .5);
  white-space: nowrap;
}

.label--flame { color: var(--flame); border-color: rgba(244, 83, 31, .55); }
.label--gold { color: var(--copper); border-color: rgba(201, 154, 70, .55); }
.label--jade { color: var(--jade); border-color: rgba(47, 163, 122, .5); }
.label--crimson { color: var(--crimson); border-color: rgba(192, 66, 46, .55); }

.panel {
  position: relative;
  padding: clamp(18px, 2.4vw, 32px);
  background: var(--ink-2);
  border: 1px solid var(--ember);
}

.panel--paper {
  background: var(--bone);
  color: var(--ink);
  border-color: rgba(8, 18, 34, .18);
  box-shadow: 6px 6px 0 rgba(58, 66, 82, .55), 12px 12px 0 rgba(58, 66, 82, .22);
}

.panel--paper .section__title,
.panel--paper h2,
.panel--paper h3,
.panel--paper h4 { color: var(--ink); }

.panel--paper .section__note,
.panel--paper p { color: #4A5468; }

.rule-ticks {
  height: 10px;
  background-image: repeating-linear-gradient(90deg, var(--ember) 0 1px, transparent 1px 16px);
  opacity: .9;
}

.note-vertical {
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .32em;
  color: var(--mist);
  text-transform: uppercase;
}

.stat { display: flex; flex-direction: column; gap: 6px; }

.stat__value {
  font-family: var(--font-mono);
  font-size: clamp(30px, 4.6vw, 54px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--copper);
  font-variant-numeric: tabular-nums;
}

.stat__unit {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .24em;
  color: var(--mist);
}

.stat__label { font-size: 13.5px; color: var(--mist); }

.data-table { font-size: 14px; }

.data-table caption {
  padding-bottom: 12px;
  text-align: left;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .24em;
  color: var(--mist);
}

.data-table th {
  padding: 10px 12px;
  text-align: left;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .18em;
  color: var(--mist);
  border-bottom: 1px solid var(--ember);
  white-space: nowrap;
}

.data-table td {
  padding: 12px;
  color: var(--bone);
  border-bottom: 1px solid rgba(58, 66, 82, .6);
  font-variant-numeric: tabular-nums;
}

.data-table tbody tr:hover { background: rgba(244, 83, 31, .08); }

.data-table .num { font-family: var(--font-mono); color: var(--copper); }
.data-table .up { color: var(--jade); }
.data-table .down { color: var(--crimson); }

/* ---------- 10. 章节目录 ---------- */
.toc { position: relative; }

.toc__title {
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .3em;
  color: var(--copper);
  text-transform: uppercase;
}

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

.toc__link {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 9px 10px;
  font-size: 13.5px;
  color: var(--mist);
  text-decoration: none;
  border-left: 1px solid var(--ember);
}

.toc__link::before {
  content: attr(data-index);
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--ember);
}

.toc__link:hover { color: var(--bone); background: rgba(243, 238, 227, .05); }

.toc__link.is-current {
  color: var(--flame);
  border-left-color: var(--flame);
  background: rgba(244, 83, 31, .09);
}

@media (min-width: 1024px) {
  .toc--sticky { position: sticky; top: calc(var(--topbar-h) + 22px); }
}

/* ---------- 11. 面包屑 ---------- */
.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .16em;
  color: var(--mist);
}

.crumbs a { color: var(--mist); text-decoration: none; }
.crumbs a:hover { color: var(--flame); }
.crumbs__sep { color: var(--ember); }
.crumbs [aria-current="page"] { color: var(--bone); }

/* ---------- 12. 媒体容器（供页面阶段放图） ---------- */
.media {
  position: relative;
  overflow: hidden;
  aspect-ratio: var(--media-ratio, 16 / 9);
  background: var(--ink-2);
  border: 1px solid var(--ember);
}

.media > img,
.media > svg,
.media > picture,
.media > picture > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media--3x2 { --media-ratio: 3 / 2; }
.media--4x3 { --media-ratio: 4 / 3; }
.media--1x1 { --media-ratio: 1 / 1; }

.media--placeholder {
  background-image:
    linear-gradient(rgba(127, 144, 168, .14) 1px, transparent 1px),
    linear-gradient(90deg, rgba(127, 144, 168, .14) 1px, transparent 1px);
  background-size: 28px 28px, 28px 28px;
}

.media::after {
  content: "";
  position: absolute;
  inset: 0;
  border: 1px solid rgba(243, 238, 227, .09);
  pointer-events: none;
}

.media__cap {
  position: absolute;
  left: 0;
  bottom: 0;
  padding: 8px 12px;
  background: rgba(8, 18, 34, .88);
  border-top: 1px solid var(--ember);
  border-right: 1px solid var(--ember);
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .2em;
  color: var(--mist);
}

/* ---------- 13. 曲线（SVG） ---------- */
.curve { width: 100%; height: auto; overflow: visible; }
.curve__grid { fill: none; stroke: rgba(127, 144, 168, .18); stroke-width: 1; }
.curve__path { fill: none; stroke-width: 2.4; stroke-linecap: round; stroke-linejoin: round; }
.curve__path--main { stroke: var(--flame); }
.curve__path--up { stroke: var(--jade); }
.curve__path--down { stroke: var(--crimson); }
.curve__path--gold { stroke: var(--copper); }

.has-js [data-draw] {
  stroke-dasharray: var(--len, 1400);
  stroke-dashoffset: var(--len, 1400);
}

.has-js [data-draw].is-visible {
  stroke-dashoffset: 0;
  transition: stroke-dashoffset 1.1s var(--ease);
}

/* ---------- 14. 滚动动效 ---------- */
.has-js .reveal {
  opacity: 0;
  transform: translateY(16px);
}

.has-js .reveal.is-visible {
  opacity: 1;
  transform: none;
  transition: opacity .6s var(--ease), transform .6s var(--ease);
}

/* ---------- 15. JS 生成控件 ---------- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  z-index: 110;
  pointer-events: none;
}

.scroll-progress__bar {
  display: block;
  height: 100%;
  width: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--flame), var(--copper));
}

.to-top {
  position: fixed;
  right: clamp(14px, 2.4vw, 30px);
  bottom: clamp(14px, 2.4vw, 30px);
  z-index: 95;
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 11px 15px;
  background: rgba(8, 18, 34, .94);
  border: 1px solid var(--copper);
  color: var(--copper);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .2em;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity .3s var(--ease), transform .3s var(--ease), visibility .3s, background-color .2s var(--ease), color .2s var(--ease);
}

.to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.to-top:hover { background: var(--copper); color: var(--ink); }

/* ---------- 16. 降低动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }

  .has-js .reveal { opacity: 1; transform: none; }

  .has-js [data-draw] {
    stroke-dasharray: none;
    stroke-dashoffset: 0;
  }
}