/* ============================================================
   企鹅课堂-免费分享 · 主站样式（方案 A · 精修升级）
   2026-10-11 视觉改版：统一设计令牌 / 内联 SVG 图标 / 分类色彩编码
   约束：强制浅色主题 / 弹性自适应 / 无黑底黑框 / 无装饰控件

   ★ 主色一律走 --accent / --accent-soft —— 后台「主色调」设置由
     app.js 的 applyBranding() 覆盖这两个变量，此处只提供默认值。
   ============================================================ */

:root {
  /* —— 品牌主色（默认＝后台 theme 设置值；被 JS 覆盖后以此为准）—— */
  --accent: #2f7cf6;
  --accent-soft: rgba(47, 124, 246, 0.10);

  /* —— 中性色 —— */
  --bg: #f5f7fb;
  --bg-2: #fafbfe;
  --card: #ffffff;
  --text: #111827;
  --text-2: #4b5563;
  --text-3: #98a1ae;
  --line: #e8ecf3;
  --line-2: #dce3ee;

  /* —— 语义色 —— */
  --ok: #16a34a;
  --ok-soft: rgba(22, 163, 74, 0.12);
  --warn: #d97706;
  --warn-soft: rgba(217, 119, 6, 0.14);
  --danger: #dc2626;
  --danger-soft: rgba(220, 38, 38, 0.10);
  --star: #f59e0b;
  --star-soft: rgba(245, 158, 11, 0.16);

  /* —— 形状与阴影 —— */
  --radius-l: 20px;
  --radius-m: 14px;
  --radius-s: 10px;
  --shadow-s: 0 1px 2px rgba(16, 24, 40, 0.04), 0 2px 8px rgba(16, 24, 40, 0.05);
  --shadow-m: 0 4px 10px rgba(16, 24, 40, 0.06), 0 16px 32px rgba(16, 24, 40, 0.09);

  /* —— 布局 —— */
  --topbar-h: 62px;
  --pad-x: 24px;
  --pad-y: 22px;
  --font: -apple-system, BlinkMacSystemFont, "SF Pro SC", "SF Pro Text",
          "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI",
          Roboto, "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; touch-action: manipulation; }

/* 内联 SVG 图标统一规格（替代 emoji / 几何符号，跨设备渲染一致） */
svg { display: block; fill: none; stroke: currentColor; stroke-width: 1.8;
      stroke-linecap: round; stroke-linejoin: round; }
.ic { width: 17px; height: 17px; flex: 0 0 auto; }

html, body {
  margin: 0; padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 15px; line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }
img { display: block; max-width: 100%; }
::selection { background: var(--accent-soft); }

/* ---------------- 顶部栏 ---------------- */
.topbar {
  position: sticky; top: 0; z-index: 60;
  height: var(--topbar-h);
  display: flex; align-items: center; gap: 16px;
  padding: 0 var(--pad-x);
  padding-left: max(var(--pad-x), env(safe-area-inset-left));
  padding-right: max(var(--pad-x), env(safe-area-inset-right));
  background: rgba(255, 255, 255, 0.86);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--line);
}

.brand { display: flex; align-items: center; gap: 11px; flex: 0 0 auto; }
.brand-logo {
  width: 38px; height: 38px;
  display: grid; place-items: center;
  font-size: 20px; line-height: 1;
  background: linear-gradient(158deg, #eaf1ff, #dce8ff);
  border-radius: 12px;
  box-shadow: inset 0 0 0 1px rgba(47, 124, 246, 0.14);
}
.brand-logo svg { width: 27px; height: 27px; stroke: none; }
.brand-text { display: flex; flex-direction: column; line-height: 1.18; min-width: 0; }
.brand-name { font-size: 16px; font-weight: 700; letter-spacing: 0.2px; }
.brand-sub { font-size: 11.5px; color: var(--text-3); }

.search { margin-left: auto; position: relative; flex: 0 1 268px; min-width: 130px; }
.search input {
  width: 100%; height: 38px;
  padding: 0 34px 0 36px;
  border-radius: 11px;
  border: 1px solid transparent;
  background: rgba(120, 128, 140, 0.10);
  color: var(--text);
  font-size: 14px; outline: none;
  -webkit-appearance: none; appearance: none;
  transition: background .18s, border-color .18s, box-shadow .18s;
}
.search input::-webkit-search-cancel-button { display: none; }
.search input::placeholder { color: var(--text-3); }
.search input:focus {
  background: #fff;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}
.search .ico {
  position: absolute; left: 12px; top: 50%;
  transform: translateY(-50%);
  width: 16px; height: 16px;
  color: var(--text-3); pointer-events: none; stroke-width: 1.9;
}
.search .clear {
  position: absolute; right: 8px; top: 50%; transform: translateY(-50%);
  width: 20px; height: 20px; border-radius: 50%;
  display: none; place-items: center;
  background: rgba(120, 128, 140, 0.22);
  color: #fff;
}
.search .clear svg { width: 12px; height: 12px; stroke-width: 2.4; }
.search.has-value .clear { display: grid; }

.topbar-right { display: flex; align-items: center; gap: 9px; flex: 0 0 auto; }
.icon-btn {
  height: 38px; padding: 0 13px;
  display: inline-flex; align-items: center; justify-content: center; gap: 7px;
  border-radius: 11px;
  background: rgba(120, 128, 140, 0.10);
  color: var(--text-2);
  font-size: 13px; font-weight: 550;
  white-space: nowrap; flex: 0 0 auto;
  transition: background .16s, color .16s;
}
.icon-btn .ic { width: 16px; height: 16px; color: var(--accent); }
.icon-btn:hover { background: rgba(120, 128, 140, 0.18); color: var(--text); }

/* ---------------- 分类导航 ---------------- */
.navwrap {
  position: sticky; top: var(--topbar-h); z-index: 55;
  background: rgba(245, 247, 251, 0.92);
  backdrop-filter: saturate(180%) blur(18px);
  -webkit-backdrop-filter: saturate(180%) blur(18px);
  border-bottom: 1px solid var(--line);
}

.nav-main {
  display: flex; align-items: center; gap: 8px;
  flex: 1 1 auto; min-width: 0;
  overflow-x: auto; scrollbar-width: none;
  padding: 0 2px;
  justify-content: flex-start;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
  mask-image: linear-gradient(90deg, #000 0, #000 calc(100% - 26px), transparent 100%);
  -webkit-mask-image: linear-gradient(90deg, #000 0, #000 calc(100% - 26px), transparent 100%);
}
.nav-main::-webkit-scrollbar { display: none; }

.tab {
  flex: 0 0 auto; height: 36px; padding: 0 14px;
  display: inline-flex; align-items: center; gap: 7px;
  border-radius: 999px;
  font-size: 14px; font-weight: 550;
  color: var(--text-2);
  background: #fff;
  box-shadow: inset 0 0 0 1px var(--line);
  transition: background .16s, color .16s, box-shadow .16s, transform .12s;
  white-space: nowrap; scroll-snap-align: center;
}
.tab .ic { width: 16px; height: 16px; }
.tab:hover { color: var(--text); box-shadow: inset 0 0 0 1px var(--line-2); }
.tab.on {
  background: var(--accent); color: #fff;
  box-shadow: 0 3px 12px var(--accent-soft), 0 1px 2px rgba(16, 24, 40, 0.10);
}
.tab .cnt { font-size: 11px; opacity: .66; font-variant-numeric: tabular-nums; }
.tab.on .cnt { opacity: .88; }

.nav-sub {
  display: flex; align-items: center; gap: 7px;
  padding: 8px var(--pad-x) 9px;
  padding-left: max(var(--pad-x), env(safe-area-inset-left));
  padding-right: max(var(--pad-x), env(safe-area-inset-right));
  overflow-x: auto; scrollbar-width: none;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}
.nav-sub::-webkit-scrollbar { display: none; }
.nav-sub:empty { display: none; }

.chip {
  flex: 0 0 auto; height: 30px; padding: 0 13px;
  display: inline-flex; align-items: center; gap: 6px;
  border-radius: 999px;
  font-size: 13px; font-weight: 500;
  color: var(--text-2);
  background: #fff;
  box-shadow: inset 0 0 0 1px var(--line);
  transition: all .16s; white-space: nowrap; scroll-snap-align: center;
}
.chip:hover { color: var(--text); box-shadow: inset 0 0 0 1px var(--line-2); }
.chip.on { background: var(--accent-soft); color: var(--accent); font-weight: 650; box-shadow: inset 0 0 0 1px var(--accent-soft); }
.chip .cnt { font-size: 11px; opacity: .68; font-variant-numeric: tabular-nums; }
.chip.on .cnt { opacity: .85; }

/* ---------------- 主体 ---------------- */
main {
  padding: var(--pad-y) var(--pad-x) 60px;
  padding-left: max(var(--pad-x), env(safe-area-inset-left));
  padding-right: max(var(--pad-x), env(safe-area-inset-right));
  max-width: 1680px; margin: 0 auto;
}

.statline {
  display: flex; align-items: center; gap: 10px;
  margin: 0 2px 14px;
  font-size: 13px; color: var(--text-2);
}
.statline b { color: var(--text); font-weight: 650; font-variant-numeric: tabular-nums; }

.announce {
  display: flex; align-items: flex-start; gap: 9px;
  margin: 0 0 16px;
  padding: 12px 15px 12px 14px;
  border-radius: var(--radius-m);
  background: linear-gradient(180deg, #eef4ff, #e8f0ff);
  border: 1px solid rgba(47, 124, 246, 0.16);
  border-left: 4px solid var(--accent);
  color: #24549e;
  font-size: 13.5px; line-height: 1.6;
  white-space: pre-wrap;
  overflow-wrap: anywhere; word-break: break-word;
}

.section-title {
  margin: 6px 2px 12px;
  font-size: 16px; font-weight: 700; color: var(--text);
  display: flex; align-items: center; gap: 9px;
}
.section-title .dot { width: 4px; height: 17px; border-radius: 2px; background: var(--accent); }

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(212px, 1fr));
  gap: 17px;
}

/* ---------------- 卡片 ---------------- */
.card {
  position: relative;
  background: var(--card);
  border-radius: var(--radius-m);
  overflow: hidden;
  box-shadow: var(--shadow-s);
  border: 1px solid var(--line);
  transition: transform .2s cubic-bezier(.22,.8,.36,1), box-shadow .2s, border-color .2s;
  cursor: pointer;
  display: flex; flex-direction: column;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-m); border-color: var(--line-2); }
.card:active { transform: translateY(-1px) scale(.995); }

.thumb {
  position: relative; width: 100%;
  aspect-ratio: 16 / 9;
  background: linear-gradient(140deg, #eef3fb, #e4ebf7);
  overflow: hidden;
}
.thumb img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform .35s cubic-bezier(.22,.8,.36,1);
}
.card:hover .thumb img { transform: scale(1.045); }
.thumb .ph {
  position: absolute; inset: 0;
  display: grid; place-items: center;
  color: var(--text-3);
}
.thumb .ph svg { width: 34px; height: 34px; stroke-width: 1.5; }

.thumb .play { position: absolute; inset: 0; display: grid; place-items: center; }
.thumb .play span {
  width: 44px; height: 44px; border-radius: 50%;
  display: grid; place-items: center;
  background: rgba(255, 255, 255, 0.94);
  color: var(--accent);
  box-shadow: 0 4px 14px rgba(16, 24, 40, 0.18);
  opacity: 0; transform: scale(.82);
  transition: all .22s cubic-bezier(.22,.8,.36,1);
}
.thumb .play svg { width: 17px; height: 17px; margin-left: 2px; stroke: none; fill: currentColor; }
.card:hover .thumb .play span { opacity: 1; transform: scale(1); }

.meta { padding: 12px 13px 13px; display: flex; flex-direction: column; gap: 9px; flex: 1; }

.title {
  font-size: 14px; font-weight: 600; line-height: 1.42;
  color: var(--text);
  /* ★ 必须保留：标题盒撑满整行，才能把编号顶到「标题那一行的最右端」 */
  flex: 1 1 auto; min-width: 0;
  display: -webkit-box; -webkit-line-clamp: 2; line-clamp: 2;
  -webkit-box-orient: vertical; overflow: hidden;
  min-height: 1.38em;
}
/* 兼容旧结构（若页面仍从旧脚本渲染出编号徽标） */
.title-row { display: flex; align-items: center; gap: 8px; min-width: 0; }
.card-idx {
  flex: 0 0 auto;
  font-size: 12px; font-weight: 700; letter-spacing: .3px;
  color: var(--accent); background: var(--accent-soft);
  padding: 2px 7px; border-radius: 7px; line-height: 1.3; white-space: nowrap;
  font-variant-numeric: tabular-nums;
}

.tags { display: flex; flex-wrap: wrap; gap: 5px; margin-top: auto; }
.tag {
  height: 22px; padding: 0 8px;
  display: inline-flex; align-items: center; gap: 4px;
  border-radius: 7px;
  font-size: 11px; font-weight: 500;
  background: rgba(120, 128, 140, 0.09);
  color: var(--text-2);
  white-space: nowrap;
}
.tag.hot { background: var(--accent-soft); color: var(--accent); }

.tags-row { display: flex; align-items: center; gap: 8px; min-width: 0; }
.tags-row .tags { flex: 1 1 auto; min-width: 0; margin-top: 0; }
.card-acts { display: inline-flex; align-items: center; gap: 6px; flex: 0 0 auto; }

.fav-btn {
  align-self: flex-start;
  height: 26px; padding: 0 10px;
  display: inline-flex; align-items: center; gap: 5px;
  border-radius: 8px;
  font-size: 12px; font-weight: 600;
  background: rgba(120, 128, 140, 0.08);
  color: var(--text-2);
  transition: all .16s;
  flex: 0 0 auto; position: relative;
}
.fav-btn .ic { width: 14px; height: 14px; }
.fav-btn:hover, .fav-btn.on { background: var(--star-soft); color: #a2690a; }
.fav-btn.on .ic { fill: var(--star); stroke: var(--star); }

.empty {
  grid-column: 1 / -1;
  padding: 70px 20px; text-align: center; color: var(--text-3);
}
.empty .big { font-size: 40px; margin-bottom: 10px; opacity: .75; }
.empty .big svg { width: 40px; height: 40px; margin: 0 auto; opacity: .55; stroke-width: 1.4; stroke: var(--text-3); }
.empty .sub { font-size: 13px; margin-top: 6px; line-height: 1.7; }

/* ---------------- 骨架屏 ---------------- */
.sk {
  position: relative; overflow: hidden;
  border-radius: var(--radius-m);
  background: #fff;
  border: 1px solid var(--line);
  min-height: 168px;
}
.sk::before {
  content: "";
  position: absolute; left: 0; right: 0; top: 0;
  height: 56.25%;
  background: linear-gradient(140deg, #eef3fb, #e4ebf7);
}
.sk::after {
  content: "";
  position: absolute; inset: 0;
  background: linear-gradient(100deg, rgba(120,128,140,0) 18%, rgba(120,128,140,.10) 42%, rgba(120,128,140,0) 66%);
  background-size: 240% 100%;
  animation: skmove 1.3s ease-in-out infinite;
}
@keyframes skmove { from { background-position: 130% 0; } to { background-position: -70% 0; } }

/* ---------------- 播放层 ---------------- */
.player {
  position: fixed; inset: 0; z-index: 200;
  display: none; flex-direction: column;
  background: #fff;
  height: 100vh;
  height: 100dvh;
}
.player.on { display: flex; }

.player-bar {
  height: 56px; flex: 0 0 auto;
  display: flex; align-items: center; gap: 12px;
  padding: 0 14px;
  padding-left: max(14px, env(safe-area-inset-left));
  padding-right: max(14px, env(safe-area-inset-right));
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--line);
}
.pbtn {
  height: 36px; padding: 0 13px;
  display: inline-flex; align-items: center; gap: 6px;
  border-radius: 10px;
  background: rgba(120, 128, 140, 0.10);
  color: var(--text);
  font-size: 13.5px; font-weight: 550;
  transition: background .16s; flex: 0 0 auto;
}
.pbtn .ic { width: 16px; height: 16px; }
.pbtn:hover { background: rgba(120, 128, 140, 0.18); }
.pbtn.primary { background: var(--accent); color: #fff; }
.pbtn.primary:hover { filter: brightness(.94); }

.player-title {
  flex: 1; min-width: 0;
  font-size: 14.5px; font-weight: 650;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.player-body { flex: 1; position: relative; background: var(--bg); overscroll-behavior: contain; }
.player-body iframe { width: 100%; height: 100%; border: 0; display: block; background: #fff; }

/* 手机端提示条 */
.player-hint {
  flex: 0 0 auto;
  display: flex; align-items: center; gap: 9px;
  padding: 9px 12px;
  padding-left: max(12px, env(safe-area-inset-left));
  padding-right: max(12px, env(safe-area-inset-right));
  background: linear-gradient(180deg, #eef4ff, #e8f0ff);
  border-bottom: 1px solid rgba(47, 124, 246, 0.16);
  color: #24549e;
  font-size: 13px; line-height: 1.5;
}
.player-hint[hidden] { display: none; }
.player-hint .hint-ic { width: 18px; height: 18px; flex: 0 0 auto; stroke-width: 1.7; }
.player-hint .hint-txt { flex: 1 1 auto; min-width: 0; }
.player-hint .hint-btn {
  flex: 0 0 auto;
  display: inline-flex; align-items: center; gap: 5px;
  height: 32px; padding: 0 11px;
  border-radius: 8px;
  background: #fff; color: var(--accent);
  font-size: 12.5px; font-weight: 650;
  box-shadow: inset 0 0 0 1px rgba(47, 124, 246, 0.22);
}
.player-hint .hint-btn .ic { width: 14px; height: 14px; }
.player-hint .hint-x {
  flex: 0 0 auto; width: 30px; height: 30px;
  display: grid; place-items: center;
  border-radius: 8px; color: #6b86b4;
}
.player-hint .hint-x svg { width: 14px; height: 14px; stroke-width: 2.2; }

.loading-mask {
  position: absolute; inset: 0;
  display: grid; place-items: center;
  background: var(--bg);
  color: var(--text-2); font-size: 14px;
}
.spinner {
  width: 22px; height: 22px; margin: 0 auto 12px;
  border: 2.5px solid var(--line-2);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin .8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ---------------- 提示条 ---------------- */
.toast {
  position: fixed; left: 50%; bottom: calc(34px + env(safe-area-inset-bottom));
  transform: translate(-50%, 20px);
  z-index: 300;
  padding: 11px 18px;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.97);
  box-shadow: var(--shadow-m);
  border: 1px solid var(--line);
  font-size: 13.5px; color: var(--text);
  opacity: 0; pointer-events: none;
  transition: all .26s cubic-bezier(.22,.8,.36,1);
  max-width: calc(100vw - 32px);
  text-align: center;
}
.toast.on { opacity: 1; transform: translate(-50%, 0); }

.footer {
  max-width: 1680px; margin: 0 auto;
  padding: 0 var(--pad-x) calc(44px + env(safe-area-inset-bottom));
  padding-left: max(var(--pad-x), env(safe-area-inset-left));
  padding-right: max(var(--pad-x), env(safe-area-inset-right));
  color: var(--text-3); font-size: 12.5px;
  text-align: center;
}

/* ============================================================
   响应式 · 5 档
   ≥1281 桌面 / 1025–1280 小桌面 / 769–1024 平板 / 431–768 手机与小平板 / ≤430 手机竖
   ============================================================ */

@media (max-width: 1280px) {
  main { --pad-y: 18px; }
  .grid { grid-template-columns: repeat(auto-fill, minmax(190px, 1fr)) !important; gap: 14px; }
}

@media (min-width: 769px) and (max-width: 1024px) {
  :root { --pad-x: 16px; }
  .grid { grid-template-columns: repeat(3, 1fr) !important; gap: 14px; }
}

@media (max-width: 900px) {
  :root { --pad-x: 14px; --pad-y: 16px; }
  .topbar { gap: 10px; }
  .brand-sub { display: none; }
  .search { flex: 1 1 auto; min-width: 0; }
  /* ★ 16px：iOS Safari 对 <16px 的输入框聚焦时会强制放大整页且不回弹 */
  .search input { height: 40px; font-size: 16px; }
  .nav-main { padding: 0 2px; }
  .grid { grid-template-columns: repeat(auto-fill, minmax(158px, 1fr)) !important; gap: 12px; }
  .title { font-size: 13.5px; }
  .footer { padding-bottom: calc(34px + env(safe-area-inset-bottom)); }
}

/* 761–900：3 列，避免这个区间卡片被切得过碎 */
@media (min-width: 761px) and (max-width: 900px) {
  .grid { grid-template-columns: repeat(3, 1fr) !important; }
}

/* ≤820：顶栏换两行（品牌 + 搜索/随机 → 分类条独占一行） */
@media (max-width: 820px) {
  .topbar {
    flex-wrap: wrap; height: auto;
    padding: 8px var(--pad-x) 6px;
    padding-left: max(var(--pad-x), env(safe-area-inset-left));
    padding-right: max(var(--pad-x), env(safe-area-inset-right));
    gap: 8px;
  }
  .brand { flex: 0 0 auto; }
  .topbar-right { flex: 1 1 0%; justify-content: flex-end; order: 2; min-width: 0; }
  .nav-main { order: 3; width: 100%; flex: 1 1 100%; padding: 2px 0 4px; }
  .nav-main .tab { height: 32px; font-size: 13px; padding: 0 12px; }
  .icon-btn span { display: none; }
  .icon-btn { padding: 0 10px; }
}

@media (max-width: 560px) {
  .grid { grid-template-columns: repeat(2, 1fr) !important; gap: 10px; }
  .meta { padding: 9px 10px 10px; }
  .player-title { font-size: 13px; }
  .pbtn .lbl { display: none; }
  .pbtn { padding: 0 11px; }
  .player-hint { padding: 8px 10px; gap: 7px; font-size: 12.5px; }
  .player-hint .hint-btn span { display: none; }
  .player-hint .hint-btn { padding: 0 9px; }
}

@media (max-width: 430px) {
  :root { --pad-x: 12px; --pad-y: 14px; }
  .brand-name { font-size: 15px; max-width: 116px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
  .brand-logo { width: 32px; height: 32px; border-radius: 10px; }
  .brand-logo svg { width: 23px; height: 23px; }
  .grid { gap: 9px; }
}

/* ============================================================
   触屏（无 hover / 粗指针）
   ============================================================ */
@media (hover: none), (pointer: coarse) {
  .thumb .play span { opacity: .92; transform: scale(1); }
  .card:hover { transform: none; }
  .card:hover .thumb img { transform: none; }
  .card:active { transform: scale(.985); }

  /* 触摸目标 ≥44px（Apple HIG 44pt / Material 48dp） */
  .tab { height: 38px; }
  .chip { min-height: 34px; }
  .icon-btn { min-height: 40px; min-width: 44px; justify-content: center; }
  .pbtn { min-height: 44px; }
  .player-hint .hint-btn { min-height: 36px; }
  .player-hint .hint-x { width: 40px; height: 40px; }

  /* 命中区撑到 44px，但视觉尺寸不变（伪元素扩展命中范围，不参与布局） */
  .fav-btn::after {
    content: "";
    position: absolute;
    left: 0; right: 0; top: 50%;
    transform: translateY(-50%);
    height: 44px;
  }
}

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: .001ms !important; transition-duration: .001ms !important; }
  .sk::after { animation: none; }
}