/* =========================================================
   亚富赛场 / 共享站点样式  assets/site.css
   深夜赛场控制台 · 粗野主义面板 · 荧光青强调
   ========================================================= */

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 96px;
}

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

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

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

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

a { color: inherit; }

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

/* ---------- 2. 变量 ---------- */
:root {
  --yf-bg: #05130F;
  --yf-panel: #0B1F19;
  --yf-cyan: #2FE8C6;
  --yf-cyan-soft: #8CF3E2;
  --yf-orange: #FF4E2B;
  --yf-amber: #FFB347;
  --yf-line: #1C3A31;
  --yf-ink: #E9FFF8;
  --yf-muted: #7CA296;
  --yf-deep: #12463A;

  --yf-wrap: 1280px;
  --yf-gutter: clamp(16px, 4vw, 48px);
  --yf-header-h: 68px;

  --yf-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --yf-cond: "Oswald", "Archivo Narrow", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --yf-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;

  --yf-ease: cubic-bezier(.22, .61, .36, 1);
  --yf-hard-shadow: 5px 5px 0 rgba(0, 0, 0, .52);
  --yf-hard-shadow-lg: 10px 10px 0 rgba(0, 0, 0, .58);
}

/* ---------- 3. 基础排版 ---------- */
body {
  min-height: 100vh;
  background-color: var(--yf-bg);
  background-image:
    radial-gradient(920px 540px at 10% -10%, rgba(18, 70, 58, .58), transparent 72%),
    radial-gradient(780px 480px at 94% 4%, rgba(47, 232, 198, .10), transparent 74%),
    repeating-linear-gradient(0deg, rgba(28, 58, 49, .26) 0 1px, transparent 1px 68px),
    repeating-linear-gradient(90deg, rgba(28, 58, 49, .18) 0 1px, transparent 1px 68px);
  background-attachment: fixed;
  color: var(--yf-ink);
  font-family: var(--yf-sans);
  font-size: 16px;
  line-height: 1.7;
  letter-spacing: .01em;
  overflow-x: hidden;
}

body.yf-no-scroll { overflow: hidden; }

h1, h2, h3, h4, h5, h6 {
  font-family: var(--yf-cond);
  font-weight: 200;
  line-height: 1.1;
  letter-spacing: .015em;
}

p { max-width: 82ch; }

strong, b { font-weight: 700; color: var(--yf-cyan-soft); }

small { font-size: 12px; color: var(--yf-muted); }

code, kbd, samp, .yf-num {
  font-family: var(--yf-mono);
  font-variant-numeric: tabular-nums;
}

::selection { background: var(--yf-cyan); color: #04120E; }

:focus-visible {
  outline: 2px solid var(--yf-cyan);
  outline-offset: 3px;
}

/* ---------- 4. 容器与栅格 ---------- */
.yf-container {
  width: min(calc(100% - var(--yf-gutter) * 2), var(--yf-wrap));
  margin-inline: auto;
}

.yf-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(16px, 2vw, 28px);
}

.yf-prose { max-width: 70ch; }
.yf-prose p + p { margin-top: 1em; }
.yf-prose > * + h2,
.yf-prose > * + h3 { margin-top: 2em; }

.yf-rule {
  height: 2px;
  border: 0;
  background: linear-gradient(90deg, var(--yf-orange), var(--yf-cyan) 55%, transparent);
  opacity: .8;
}

.yf-eyebrow {
  font-family: var(--yf-mono);
  font-size: 11px;
  letter-spacing: .26em;
  text-transform: uppercase;
  color: var(--yf-muted);
}

.yf-display {
  font-family: var(--yf-cond);
  font-weight: 200;
  font-size: clamp(46px, 9vw, 118px);
  line-height: .94;
  letter-spacing: -.01em;
}
.yf-display strong { font-weight: 800; color: var(--yf-cyan); }

/* ---------- 5. Skip link ---------- */
.yf-skip {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 300;
  transform: translateY(-240%);
  padding: 11px 18px;
  background: var(--yf-cyan);
  color: #04120E;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .1em;
  text-decoration: none;
  border: 2px solid #04120E;
  transition: transform .22s var(--yf-ease);
}
.yf-skip:focus { transform: translateY(0); }

/* ---------- 6. 头部 ---------- */
.yf-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: linear-gradient(180deg, rgba(5, 19, 15, .97), rgba(5, 19, 15, .88));
  border-bottom: 2px solid var(--yf-line);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.yf-header__inner {
  width: min(calc(100% - var(--yf-gutter) * 2), var(--yf-wrap));
  margin-inline: auto;
  display: flex;
  align-items: center;
  gap: clamp(12px, 2vw, 30px);
  padding-block: 14px;
  transition: padding-block .24s var(--yf-ease);
}

.yf-header--slim .yf-header__inner { padding-block: 8px; }
.yf-header--slim .yf-brand__tagline { display: none; }

/* 品牌 */
.yf-brand {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--yf-ink);
}

.yf-brand__mark {
  width: 34px;
  height: 34px;
  flex: 0 0 auto;
  background: linear-gradient(135deg, var(--yf-cyan) 0 38%, var(--yf-deep) 38% 62%, var(--yf-orange) 62% 100%);
  border: 2px solid var(--yf-line);
  box-shadow: 4px 4px 0 rgba(0, 0, 0, .5);
  clip-path: polygon(0 0, 100% 0, 100% 68%, 68% 100%, 0 100%);
  transition: transform .22s var(--yf-ease);
}
.yf-brand:hover .yf-brand__mark { transform: rotate(-6deg); }

.yf-brand__text { display: flex; flex-direction: column; line-height: 1.12; }

.yf-brand__name {
  font-family: var(--yf-cond);
  font-size: 19px;
  font-weight: 800;
  letter-spacing: .16em;
}

.yf-brand__tagline {
  font-size: 10.5px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--yf-muted);
}

/* 轮次状态 */
.yf-season {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 11px;
  font-family: var(--yf-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--yf-cyan);
  background: rgba(11, 31, 25, .82);
  border: 1px solid var(--yf-line);
  white-space: nowrap;
}

.yf-season__dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--yf-cyan);
  box-shadow: 0 0 0 4px rgba(47, 232, 198, .16);
  animation: yf-pulse 2.4s var(--yf-ease) infinite;
}

@keyframes yf-pulse {
  0%, 100% { box-shadow: 0 0 0 4px rgba(47, 232, 198, .16); }
  50% { box-shadow: 0 0 0 8px rgba(47, 232, 198, .04); }
}

/* ---------- 7. 导航 ---------- */
.yf-nav { margin-left: auto; }

.yf-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(2px, .7vw, 10px);
}

.yf-nav__item { display: block; }

.yf-nav__link {
  display: inline-block;
  padding: 8px 10px;
  font-size: 13.5px;
  letter-spacing: .04em;
  text-decoration: none;
  color: var(--yf-ink);
  border-bottom: 2px solid transparent;
  transition: color .22s var(--yf-ease), background-color .22s var(--yf-ease), border-color .22s var(--yf-ease);
}

.yf-nav__link:hover { color: var(--yf-cyan); background: rgba(47, 232, 198, .08); }

.yf-nav__link[aria-current="page"] {
  color: var(--yf-cyan);
  border-bottom-color: var(--yf-orange);
  background: rgba(47, 232, 198, .1);
}

.yf-nav__foot { display: none; }

/* 右侧工具区 */
.yf-header__tools {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 12px;
}

.yf-nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 9px 12px;
  background: var(--yf-panel);
  border: 2px solid var(--yf-line);
  color: var(--yf-ink);
  font-size: 12px;
  letter-spacing: .16em;
  box-shadow: var(--yf-hard-shadow);
  transition: border-color .2s var(--yf-ease), color .2s var(--yf-ease);
}
.yf-nav-toggle:hover { border-color: var(--yf-cyan); color: var(--yf-cyan); }
.yf-nav-toggle[aria-expanded="true"] { border-color: var(--yf-orange); color: var(--yf-orange); }

.yf-nav-toggle__bars {
  position: relative;
  display: inline-block;
  width: 18px;
  height: 12px;
}
.yf-nav-toggle__bars::before,
.yf-nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 2px;
  background: currentColor;
  transition: transform .24s var(--yf-ease);
}
.yf-nav-toggle__bars::before { top: 1px; }
.yf-nav-toggle__bars::after { bottom: 1px; }
.yf-nav-toggle[aria-expanded="true"] .yf-nav-toggle__bars::before { transform: translateY(4px) rotate(45deg); }
.yf-nav-toggle[aria-expanded="true"] .yf-nav-toggle__bars::after { transform: translateY(-4px) rotate(-45deg); }

/* ---------- 8. 阅读进度 ---------- */
.yf-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 3px;
  background: rgba(28, 58, 49, .8);
  overflow: hidden;
}

.yf-progress__bar {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--yf-orange), var(--yf-amber) 38%, var(--yf-cyan));
  transition: width .12s linear;
}

/* ---------- 9. 按钮与标签 ---------- */
.yf-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 18px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .1em;
  text-decoration: none;
  color: var(--yf-ink);
  background: var(--yf-panel);
  border: 2px solid var(--yf-line);
  box-shadow: var(--yf-hard-shadow);
  transition: transform .2s var(--yf-ease), box-shadow .2s var(--yf-ease), border-color .2s var(--yf-ease), color .2s var(--yf-ease);
}

.yf-btn:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--yf-hard-shadow-lg);
  border-color: var(--yf-cyan);
  color: var(--yf-cyan);
}

.yf-btn--primary {
  background: linear-gradient(120deg, var(--yf-cyan), #17B79C);
  color: #04120E;
  border-color: #04120E;
}
.yf-btn--primary:hover { color: #04120E; border-color: var(--yf-orange); }

.yf-btn--ghost { background: transparent; }

.yf-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  font-family: var(--yf-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--yf-cyan);
  border: 1px solid rgba(47, 232, 198, .4);
  background: rgba(47, 232, 198, .08);
  white-space: nowrap;
}
.yf-tag--hot { color: var(--yf-orange); border-color: rgba(255, 78, 43, .45); background: rgba(255, 78, 43, .1); }
.yf-tag--warn { color: var(--yf-amber); border-color: rgba(255, 179, 71, .45); background: rgba(255, 179, 71, .1); }
.yf-tag--cool { color: var(--yf-muted); border-color: var(--yf-line); background: rgba(28, 58, 49, .5); }

/* ---------- 10. 章节体系 ---------- */
.yf-section { padding-block: clamp(40px, 7vw, 88px); }

.yf-section__band {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 14px;
  padding-top: 12px;
  margin-bottom: 24px;
  border-top: 3px solid transparent;
  border-image: linear-gradient(90deg, var(--yf-orange), var(--yf-cyan) 70%, transparent) 1;
}

.yf-section__num {
  font-family: var(--yf-mono);
  font-size: 12px;
  letter-spacing: .24em;
  color: var(--yf-orange);
}

.yf-section__title {
  font-family: var(--yf-cond);
  font-weight: 200;
  font-size: clamp(28px, 4vw, 38px);
  letter-spacing: .02em;
}

.yf-section__kicker {
  margin-left: auto;
  font-family: var(--yf-mono);
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--yf-muted);
}

/* ---------- 11. 锚点栏 ---------- */
.yf-anchor {
  position: sticky;
  top: calc(var(--yf-header-h) + 28px);
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding-left: 14px;
  border-left: 2px solid var(--yf-line);
}

.yf-anchor__link {
  display: block;
  padding: 5px 0;
  font-family: var(--yf-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--yf-muted);
  text-decoration: none;
  transition: color .2s var(--yf-ease), transform .2s var(--yf-ease);
}
.yf-anchor__link:hover { color: var(--yf-ink); transform: translateX(3px); }
.yf-anchor__link[aria-current="true"] { color: var(--yf-cyan); }

/* ---------- 12. 面板与数据 ---------- */
.yf-panel {
  position: relative;
  padding: clamp(18px, 2.2vw, 28px);
  background: var(--yf-panel);
  border: 2px solid var(--yf-line);
  transition: border-color .22s var(--yf-ease), transform .22s var(--yf-ease);
}
.yf-panel:hover { border-color: rgba(47, 232, 198, .55); }
.yf-panel--raised { box-shadow: var(--yf-hard-shadow-lg); }

.yf-panel--grad {
  background:
    linear-gradient(150deg, rgba(18, 70, 58, .9), rgba(11, 31, 25, .95) 55%, rgba(5, 19, 15, 1)),
    var(--yf-panel);
}

.yf-stat { display: flex; flex-direction: column; gap: 4px; }

.yf-stat__value {
  font-family: var(--yf-mono);
  font-size: clamp(44px, 6vw, 112px);
  font-weight: 700;
  line-height: .9;
  letter-spacing: -.02em;
  color: var(--yf-ink);
}
.yf-stat__value--hot { color: var(--yf-orange); }
.yf-stat__value--cyan { color: var(--yf-cyan); }

.yf-stat__label {
  font-family: var(--yf-mono);
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--yf-muted);
}

.yf-stat__delta {
  font-family: var(--yf-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--yf-amber);
  border-bottom: 2px solid var(--yf-orange);
  align-self: flex-start;
}

.yf-data-bar {
  position: relative;
  height: 8px;
  background: rgba(28, 58, 49, .75);
  overflow: hidden;
}
.yf-data-bar__fill {
  display: block;
  height: 100%;
  width: var(--fill, 50%);
  background: linear-gradient(90deg, var(--yf-cyan), var(--yf-cyan-soft));
  transition: width .32s var(--yf-ease);
}
.yf-data-bar--hot .yf-data-bar__fill { background: linear-gradient(90deg, var(--yf-orange), var(--yf-amber)); }

/* ---------- 13. 表格 ---------- */
.yf-table-wrap {
  width: 100%;
  overflow-x: auto;
  border: 2px solid var(--yf-line);
  background: var(--yf-panel);
}

.yf-table { min-width: 560px; font-size: 14px; }

.yf-table th,
.yf-table td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: 1px solid var(--yf-line);
}

.yf-table th {
  font-family: var(--yf-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--yf-muted);
  background: rgba(18, 70, 58, .45);
  white-space: nowrap;
}

.yf-table tbody tr:hover { background: rgba(47, 232, 198, .06); }
.yf-table td.yf-num { color: var(--yf-cyan); font-weight: 700; }

/* ---------- 14. 步骤 ---------- */
.yf-steps { display: grid; gap: 14px; }

.yf-step {
  display: grid;
  grid-template-columns: 54px minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  padding: 16px 18px;
  background: var(--yf-panel);
  border: 2px solid var(--yf-line);
  border-left: 4px solid var(--yf-cyan);
}

.yf-step__index {
  font-family: var(--yf-mono);
  font-size: 26px;
  font-weight: 700;
  line-height: 1;
  color: var(--yf-orange);
}

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

.yf-step__title { font-size: 17px; font-weight: 700; letter-spacing: .02em; }

/* ---------- 15. 横向主题带 ---------- */
.yf-track {
  display: flex;
  gap: 16px;
  overflow-x: auto;
  padding: 4px 2px 18px;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}
.yf-track::-webkit-scrollbar { height: 6px; }
.yf-track::-webkit-scrollbar-track { background: rgba(28, 58, 49, .6); }
.yf-track::-webkit-scrollbar-thumb { background: var(--yf-cyan); }

.yf-track__item {
  flex: 0 0 min(320px, 78vw);
  scroll-snap-align: start;
}

/* ---------- 16. 更新日志 / 时间轴 ---------- */
.yf-log { display: grid; gap: 0; }

.yf-log__item {
  position: relative;
  padding: 18px 0 18px 30px;
  border-left: 2px solid var(--yf-line);
}

.yf-log__item:last-child { border-left-color: transparent; }

.yf-log__mark {
  position: absolute;
  left: -7px;
  top: 24px;
  width: 12px;
  height: 12px;
  background: var(--yf-bg);
  border: 2px solid var(--yf-cyan);
  transform: rotate(45deg);
}
.yf-log__item--hot .yf-log__mark { border-color: var(--yf-orange); }

.yf-log__meta {
  font-family: var(--yf-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--yf-muted);
}

.yf-log__title { font-size: 18px; font-weight: 700; margin: 4px 0 6px; }

/* ---------- 17. 图片容器 ---------- */
.yf-media {
  position: relative;
  overflow: hidden;
  border: 2px solid var(--yf-line);
  background: linear-gradient(140deg, var(--yf-panel), var(--yf-deep) 62%, var(--yf-bg));
}

.yf-media--wide { aspect-ratio: 16 / 9; }
.yf-media--band { aspect-ratio: 21 / 9; }
.yf-media--tall { aspect-ratio: 3 / 4; }
.yf-media--square { aspect-ratio: 1 / 1; }

.yf-media__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.86) contrast(1.06) brightness(.9);
}

.yf-media__grid {
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(0deg, rgba(47, 232, 198, .09) 0 1px, transparent 1px 42px),
    repeating-linear-gradient(90deg, rgba(47, 232, 198, .07) 0 1px, transparent 1px 42px),
    linear-gradient(180deg, rgba(5, 19, 15, .1), rgba(5, 19, 15, .88));
  pointer-events: none;
}

.yf-media__label {
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 12px;
  z-index: 2;
  font-family: var(--yf-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--yf-cyan-soft);
}

/* ---------- 18. 面包屑 ---------- */
.yf-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 18px 0 0;
  font-family: var(--yf-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--yf-muted);
}
.yf-breadcrumb a { text-decoration: none; color: var(--yf-muted); }
.yf-breadcrumb a:hover { color: var(--yf-cyan); }
.yf-breadcrumb span[aria-hidden="true"] { color: var(--yf-line); }

/* ---------- 19. 页脚 ---------- */
.yf-footer {
  position: relative;
  margin-top: clamp(48px, 8vw, 110px);
  background: linear-gradient(180deg, var(--yf-panel), var(--yf-bg) 68%);
  border-top: 2px solid var(--yf-line);
}

.yf-footer__stripe {
  height: 6px;
  background: linear-gradient(90deg, var(--yf-orange), var(--yf-amber) 28%, var(--yf-cyan) 68%, var(--yf-deep));
}

.yf-footer__inner {
  width: min(calc(100% - var(--yf-gutter) * 2), var(--yf-wrap));
  margin-inline: auto;
  display: grid;
  grid-template-columns: minmax(230px, 1fr) 2.1fr;
  gap: clamp(24px, 4vw, 64px);
  padding: clamp(32px, 5vw, 64px) 0 clamp(24px, 3vw, 40px);
}

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

.yf-brand--footer .yf-brand__name { font-size: 21px; }

.yf-footer__line { font-size: 13px; color: var(--yf-muted); max-width: 26ch; }

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

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

.yf-footer__title {
  font-family: var(--yf-mono);
  font-size: 11px;
  font-weight: 400;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--yf-cyan);
}

.yf-footer__list { display: grid; gap: 8px; }

.yf-footer__link {
  font-size: 13.5px;
  text-decoration: none;
  color: var(--yf-ink);
  border-bottom: 1px solid transparent;
  transition: color .2s var(--yf-ease), border-color .2s var(--yf-ease);
}
.yf-footer__link:hover { color: var(--yf-cyan); border-bottom-color: var(--yf-orange); }

.yf-footer__text { font-size: 13.5px; line-height: 1.85; color: var(--yf-muted); }
.yf-footer__col--contact .yf-footer__text { color: var(--yf-ink); }

.yf-footer__bottom {
  width: min(calc(100% - var(--yf-gutter) * 2), var(--yf-wrap));
  margin-inline: auto;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 22px;
  padding: 18px 0 30px;
  border-top: 1px solid var(--yf-line);
  font-size: 12px;
  color: var(--yf-muted);
}

.yf-footer__legal {
  font-family: var(--yf-mono);
  letter-spacing: .1em;
  color: var(--yf-cyan-soft);
}

.yf-footer__note { flex: 1 1 320px; max-width: 60ch; }

.yf-footer__copy { font-family: var(--yf-mono); letter-spacing: .08em; }

/* ---------- 20. 显现与返回顶部 ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity .5s var(--yf-ease), transform .5s var(--yf-ease);
}
[data-reveal].is-in { opacity: 1; transform: none; }

.yf-backtop {
  position: fixed;
  right: 18px;
  bottom: 18px;
  z-index: 90;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  background: var(--yf-panel);
  border: 2px solid var(--yf-line);
  color: var(--yf-cyan);
  font-family: var(--yf-mono);
  font-size: 12px;
  letter-spacing: .08em;
  box-shadow: var(--yf-hard-shadow);
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity .24s var(--yf-ease), transform .24s var(--yf-ease), visibility 0s linear .24s;
}
.yf-backtop.is-on {
  opacity: 1;
  visibility: visible;
  transform: none;
  transition: opacity .24s var(--yf-ease), transform .24s var(--yf-ease), visibility 0s;
}
.yf-backtop:hover { border-color: var(--yf-cyan); }

/* 页面区块滚动定位 */
[data-observe] { scroll-margin-top: calc(var(--yf-header-h) + 24px); }

/* ---------- 21. 响应式 ---------- */
@media (max-width: 1120px) {
  .yf-nav-toggle { display: inline-flex; }
  .yf-brand__tagline { display: none !important; }

  .yf-nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    z-index: 80;
    width: min(84vw, 340px);
    margin-left: 0;
    display: flex;
    flex-direction: column;
    padding: 96px var(--yf-gutter) var(--yf-gutter);
    background: linear-gradient(180deg, var(--yf-panel), var(--yf-bg));
    border-left: 2px solid var(--yf-line);
    overflow-y: auto;
    transform: translateX(103%);
    visibility: hidden;
    transition: transform .3s var(--yf-ease), visibility 0s linear .3s;
  }

  .yf-nav[data-open] {
    transform: none;
    visibility: visible;
    box-shadow: -100vmax 0 0 100vmax rgba(5, 19, 15, .72);
    transition: transform .3s var(--yf-ease), visibility 0s;
  }

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

  .yf-nav__link {
    display: block;
    padding: 14px 4px;
    font-size: 15px;
    border-bottom: 1px solid var(--yf-line);
    border-left: 3px solid transparent;
  }
  .yf-nav__link[aria-current="page"] {
    border-bottom-color: var(--yf-line);
    border-left-color: var(--yf-orange);
    background: rgba(47, 232, 198, .08);
  }

  .yf-nav__foot {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
    margin-top: auto;
    padding-top: 20px;
    border-top: 1px dashed var(--yf-line);
  }
  .yf-nav__foot-line {
    font-family: var(--yf-mono);
    font-size: 11px;
    letter-spacing: .14em;
    color: var(--yf-muted);
  }

  .yf-footer__inner { grid-template-columns: 1fr; }
}

@media (max-width: 820px) {
  body { font-size: 15.5px; }

  .yf-season { display: none; }
  .yf-header__cta { display: none; }
  .yf-header__inner { padding-block: 10px; }

  .yf-footer__cols { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .yf-footer__col--contact { grid-column: 1 / -1; }

  .yf-section__kicker { margin-left: 0; flex-basis: 100%; }

  .yf-step { grid-template-columns: 40px minmax(0, 1fr); gap: 12px; padding: 14px; }
  .yf-step__index { font-size: 22px; }
}

@media (max-width: 560px) {
  .yf-grid { grid-template-columns: repeat(6, minmax(0, 1fr)); }
  .yf-footer__cols { grid-template-columns: 1fr; }
  .yf-brand__mark { width: 30px; height: 30px; }
  .yf-nav-toggle__label { display: none; }
  .yf-backtop { right: 12px; bottom: 12px; }
  .yf-track__item { flex-basis: 82vw; }
}

/* ---------- 22. 无障碍与降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

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

  [data-reveal] { opacity: 1 !important; transform: none !important; }
  .yf-season__dot { animation: none; }
  .yf-progress__bar { transition: none; }
}

@media print {
  .yf-header, .yf-footer__stripe, .yf-nav-toggle, .yf-backtop { display: none; }
  body { background: #fff; color: #000; }
}