/* =========================
扭蛋 niudan 官网（www.niudan.cc）
版式参考 DeepSeek：浅色云雾背景、居中标题、玻璃面板、胶囊入口。
扭蛋自己的部分：暖色云雾里藏着胶囊的红与灰、可筛选的产品面板、扭蛋红只给 Logo 和行动点。
=========================== */
:root {
  --bg: #f9f8f7;
  --ink: #1a1a1c;
  --ink-2: rgb(26 26 28 / 0.72);
  --ink-3: rgb(26 26 28 / 0.5);
  --ink-4: rgb(26 26 28 / 0.32);
  --line: rgb(26 26 28 / 0.08);
  --glass: rgb(255 255 255 / 0.62);
  --glass-line: rgb(255 255 255 / 0.9);
  --red: #e8402f;
  --red-soft: #fdecea;
  --green: #16b67f;

  --font: 'HarmonyOS Sans SC', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', system-ui, -apple-system, sans-serif;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 72px;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  overflow-x: clip;
  background: var(--bg);
  color: var(--ink-2);
  font-family: var(--font);
  font-size: 15px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
p,
ul {
  margin: 0;
}

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

a {
  color: inherit;
  text-decoration: none;
}

svg {
  display: block;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

:focus-visible {
  outline: 2px solid var(--red);
  outline-offset: 2px;
}

/* =============== 容器宽度（与 DeepSeek 一致） =============== */
/* <768：两侧各 24；768~1559：最宽 1140；≥1560：最宽 1280 */
.nav-bar,
.wrap,
.footer-inner,
.footer-bottom {
  width: min(100% - 48px, 1140px);
  margin-inline: auto;
}
@media (min-width: 768px) {
  .nav-bar,
  .wrap,
  .footer-inner,
  .footer-bottom {
    width: min(100% - 144px, 1140px);
  }
}
@media (min-width: 1560px) {
  .nav-bar,
  .wrap,
  .footer-inner,
  .footer-bottom {
    width: min(100% - 160px, 1280px);
  }
}

/* =============== Logo =============== */
.logo {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--ink);
}
.logo-mark {
  width: 26px;
  height: 26px;
}
.logo-word {
  font-size: 21px;
  font-weight: 700;
  letter-spacing: -0.02em;
}

/* =============== 导航：滚动后收成悬浮胶囊 =============== */
.nav {
  position: fixed;
  inset: 0 0 auto;
  z-index: 50;
  padding: 8px 0 0;
  pointer-events: none;
}
.nav-bar {
  /* 尺寸与 DeepSeek 实测一致：展开跟随容器，收起 980（≥1560 时 1180），高 46 */
  display: flex;
  align-items: center;
  gap: 40px;
  max-width: 1280px;
  height: 46px;
  padding: 4px 0;
  border: 1px solid transparent;
  border-radius: 100px;
  pointer-events: auto;
  transition:
    max-width 0.5s var(--ease),
    padding 0.5s var(--ease),
    background-color 0.3s,
    border-color 0.3s,
    backdrop-filter 0.3s;
}
.nav.is-floating .nav-bar {
  max-width: 980px;
  padding: 4px 6px 4px 16px;
  background: rgb(255 255 255 / 0.45);
  border-color: rgb(0 0 0 / 0.1);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}
@media (min-width: 1560px) {
  .nav.is-floating .nav-bar {
    max-width: 1180px;
  }
}
.nav-links {
  display: flex;
  gap: 28px;
  margin-left: auto;
  font-size: 14px;
}
.nav-links a {
  color: var(--ink-2);
  transition: color 0.2s;
}
.nav-links a:hover {
  color: var(--ink);
}
.nav-cta {
  padding: 7px 16px;
  border-radius: 999px;
  background: var(--ink);
  color: #fff;
  font-size: 13px;
  font-weight: 500;
  transition: background-color 0.3s;
}
.nav-cta:hover {
  background: var(--red);
}

/* =============== 首屏 =============== */
.hero {
  /* 不设定位：背景层相对整页定位，可以一路延伸到下一屏再淡出 */
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: max(100svh, 760px);
  padding: 120px 0 96px;
}

/* 云雾：一层缓慢旋转的极光 + 五团沿各自路径流动的模糊色块，整体再跟随指针轻微视差。
   暖白里带一点胶囊的红与灰；只动 transform，交给合成层，不重排 */
.sky {
  /* 从页面顶部铺到第二屏，颜色在首屏最浓，往下缓缓淡出到浅色底 */
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: max(170svh, 1400px);
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
  -webkit-mask-image: linear-gradient(to bottom, #000 0%, #000 38%, rgb(0 0 0 / 0.78) 54%, rgb(0 0 0 / 0.46) 70%, rgb(0 0 0 / 0.16) 86%, transparent 100%);
  mask-image: linear-gradient(to bottom, #000 0%, #000 38%, rgb(0 0 0 / 0.78) 54%, rgb(0 0 0 / 0.46) 70%, rgb(0 0 0 / 0.16) 86%, transparent 100%);
  transform: translate3d(calc(var(--px, 0) * -24px), calc(var(--py, 0) * -16px), 0);
  transition: transform 1.2s var(--ease);
}
.sky::before {
  /* 极光：大幅锥形渐变慢慢旋转，模糊后像一层流动的光 */
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 140vmax;
  height: 140vmax;
  margin: -70vmax 0 0 -70vmax;
  background: conic-gradient(from 0deg, #f7dcd3, #eceaf3, #fbeee6, #e4e6ef, #f9e1da, #f1efea, #f7dcd3);
  filter: blur(60px);
  opacity: 0.75;
  animation: spin 48s linear infinite;
}
.cloud {
  position: absolute;
  z-index: 1;
  border-radius: 50%;
  filter: blur(64px);
  will-change: transform;
  animation: flow-a 18s ease-in-out infinite;
}
.c1 {
  top: 2%;
  left: 2%;
  width: 46vw;
  height: 36vw;
  background: #e3e5ef;
}
.c2 {
  top: 4%;
  right: 0;
  width: 42vw;
  height: 34vw;
  background: #f5d6cc;
  animation-name: flow-b;
  animation-duration: 22s;
}
.c3 {
  top: 40%;
  left: 22%;
  width: 30vw;
  height: 20vw;
  background: #fbe4db;
  animation-name: flow-c;
  animation-duration: 16s;
}
.c4 {
  top: 30%;
  right: 14%;
  width: 24vw;
  height: 18vw;
  background: #e8e6e1;
  animation-name: flow-b;
  animation-duration: 20s;
  animation-direction: reverse;
}
.c5 {
  /* 一点胶囊红，最淡的一团，在标题后面来回游动 */
  top: 22%;
  left: 40%;
  width: 20vw;
  height: 14vw;
  background: #f3b9ab;
  opacity: 0.45;
  animation-name: flow-c;
  animation-duration: 24s;
  animation-direction: reverse;
}
/* WebGL 流动背景（flow.js）；跑起来后隐藏 CSS 云雾兜底 */
.flow {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  filter: blur(8px);
  transform: scale(1.03);
}
.has-flow .sky {
  transform: none;
}
.has-flow .sky::before,
.has-flow .cloud {
  display: none;
}
.sky:not(:has(.flow)) .flow,
.hero:not(.has-flow) .flow {
  display: none;
}

.hero-inner {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
  max-width: 1080px;
  padding: 0 24px;
  text-align: center;
}
.hero-inner > * {
  animation: rise 0.8s var(--ease) both;
  animation-delay: calc(var(--i, 0) * 0.06s + 0.05s);
}

.notice {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  max-width: 100%;
  padding: 6px 14px 6px 8px;
  border: 1px solid rgb(255 255 255 / 0.9);
  border-radius: 999px;
  background: rgb(255 255 255 / 0.55);
  color: var(--ink-2);
  font-size: 13px;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  transition: background-color 0.3s;
}
.notice:hover {
  background: rgb(255 255 255 / 0.85);
}
.notice span {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.notice-mark {
  flex: none;
  width: 16px;
  height: 16px;
}
.notice i {
  font-style: normal;
  color: var(--ink-3);
  transition: transform 0.3s var(--ease);
}
.notice:hover i {
  transform: translateX(3px);
}

.hero h1 {
  width: 100%;
  margin-top: 28px;
  white-space: nowrap;
  color: var(--ink);
  font-size: 46px;
  font-weight: 500;
  line-height: 1.5;
  --ls: 0.12em;
  letter-spacing: var(--ls);
  /* 字距会在最后一个字后多出一截，用缩进抵消，保持视觉居中 */
  text-indent: var(--ls);
}
/* 打字机：两句标语轮换，光标是一根细细的扭蛋红竖线 */
.type::after {
  content: '';
  display: inline-block;
  width: 2px;
  height: 0.9em;
  /* 抵掉末字后的字距，再留一点空隙 */
  margin-left: calc(0.06em - var(--ls));
  vertical-align: -0.08em;
  background: var(--red);
  animation: caret 1s steps(1) infinite;
}
.type.is-typing::after {
  animation: none;
}
.hero-sub {
  margin-top: 10px;
  color: var(--ink-3);
  font-size: 16px;
  letter-spacing: 0.12em;
}

/* =============== 产品面板 =============== */
.panel {
  width: 100%;
  max-width: 880px;
  margin-top: 40px;
  padding: 8px;
  border: 1px solid var(--glass-line);
  border-radius: 24px;
  background: var(--glass);
  box-shadow:
    0 1px 0 rgb(255 255 255 / 0.8) inset,
    0 24px 60px -30px rgb(60 40 30 / 0.22);
  backdrop-filter: saturate(1.4) blur(22px);
  -webkit-backdrop-filter: saturate(1.4) blur(22px);
  text-align: left;
}
.panel-search {
  display: flex;
  align-items: center;
  gap: 10px;
  height: 52px;
  padding: 0 14px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 6px;
  color: var(--ink-3);
}
.panel-search svg {
  flex: none;
  width: 18px;
  height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
}
.panel-search input {
  flex: 1;
  min-width: 0;
  border: 0;
  outline: 0;
  background: transparent;
  color: var(--ink);
  font: inherit;
  font-size: 15px;
}
.panel-search input::placeholder {
  color: var(--ink-4);
}
.panel-search kbd {
  padding: 1px 7px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: rgb(255 255 255 / 0.7);
  color: var(--ink-3);
  font: inherit;
  font-size: 12px;
}

.item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 12px 14px;
  border-radius: 16px;
  outline: none;
  transition: background-color 0.2s;
}
.item.is-current {
  background: rgb(255 255 255 / 0.85);
}
.item-icon {
  display: grid;
  flex: none;
  place-items: center;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgb(255 255 255 / 0.8);
  color: var(--ink-2);
}
.item-icon svg {
  width: 20px;
  height: 20px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.6;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.item-icon.is-solid svg {
  width: 26px;
  height: 26px;
}
.item-icon.is-dashed {
  border-style: dashed;
  border-color: var(--ink-4);
  background: transparent;
}
.item-main {
  display: flex;
  flex: 1;
  flex-direction: column;
  min-width: 0;
  line-height: 1.45;
}
.item-main strong {
  color: var(--ink);
  font-size: 15px;
  font-weight: 500;
}
.item-main small {
  overflow: hidden;
  color: var(--ink-3);
  font-size: 13px;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.item-domain {
  color: var(--ink-4);
  font-size: 13px;
  white-space: nowrap;
}
.item-state {
  flex: none;
  min-width: 64px;
  padding: 2px 10px;
  border-radius: 999px;
  background: rgb(26 26 28 / 0.05);
  color: var(--ink-3);
  font-size: 12px;
  text-align: center;
}
.item-state.is-live {
  background: color-mix(in oklab, var(--green) 12%, white);
  color: var(--green);
}
.item-go {
  display: grid;
  flex: none;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--red);
  color: #fff;
  transition: transform 0.3s var(--ease);
}
.item-go svg {
  width: 16px;
  height: 16px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.item.is-current .item-go {
  transform: translate(2px, -2px);
}
.panel-empty {
  padding: 18px 14px 20px;
  color: var(--ink-3);
  font-size: 14px;
}

.quick {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  margin-top: 28px;
}
.quick a {
  padding: 8px 18px;
  border: 1px solid rgb(255 255 255 / 0.95);
  border-radius: 999px;
  background: rgb(255 255 255 / 0.6);
  color: var(--ink-2);
  font-size: 14px;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  transition:
    background-color 0.3s,
    color 0.3s;
}
.quick a:hover {
  background: #fff;
  color: var(--ink);
}

/* =============== 关于 / 常见问题 =============== */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--ink-3);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.16em;
}
.eyebrow::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--red);
}

/* 关于、FAQ 与收起后的导航同宽：980，≥1560 时 1180 */
.about .wrap,
.faq .wrap {
  max-width: 980px;
}
@media (min-width: 1560px) {
  .about .wrap,
  .faq .wrap {
    max-width: 1180px;
  }
}
.about {
  padding: 72px 0 128px;
}
/* 字号阶梯：首屏 46 > 板块标题 32 > 小标题 16~18 > 正文 14~15 > 辅助 12~13 */
.faq .sec-center h2 {
  margin-top: 16px;
  color: var(--ink);
  font-size: 32px;
  font-weight: 500;
  line-height: 1.3;
  letter-spacing: 0.01em;
}

/* 标题区居中，和首屏同一条中轴 */
.sec-center {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}
.sec-center .eyebrow {
  margin: 0;
}
.manifesto {
  margin-top: 16px;
  color: var(--ink);
  font-size: 32px;
  font-weight: 500;
  line-height: 1.3;
  letter-spacing: 0.02em;
}
.manifesto br {
  /* 桌面一行，手机在逗号后换行 */
  display: none;
}
.sec-sub {
  margin-top: 12px;
  color: var(--ink-3);
  font-size: 15px;
  text-wrap: balance;
}

/* 一张卡片：上面是聚合关系图（AI → 扭蛋 → 旗下产品，连线上有光点流动），下面一栏三条原则 */
.hub {
  margin: 48px 0 0;
  padding: 44px 40px 0;
  border: 1px solid rgb(255 255 255 / 0.9);
  border-radius: 28px;
  background: rgb(255 255 255 / 0.6);
  box-shadow:
    0 1px 0 rgb(255 255 255 / 0.9) inset,
    0 30px 60px -40px rgb(60 40 30 / 0.25);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}
.hub-grid {
  position: relative;
  display: grid;
  grid-template-columns: 1fr auto 1.3fr;
  align-items: center;
  gap: 96px;
}
.hub-lines {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  overflow: visible;
  pointer-events: none;
}
.hub-lines path {
  fill: none;
  stroke: rgb(26 26 28 / 0.12);
  stroke-width: 1;
}
.hub-lines path.is-dashed {
  stroke-dasharray: 3 5;
}
.hub-lines path.pulse {
  stroke: var(--red);
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-dasharray: 7 93;
  animation: pulse-run 3.2s linear infinite;
}
.hub-src,
.hub-dst {
  position: relative;
  display: grid;
  gap: 14px;
}
.hub-src {
  justify-items: start;
}
.hub-src li {
  padding: 8px 16px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  color: var(--ink-2);
  font-size: 13px;
}
.hub-core {
  position: relative;
  display: grid;
  place-items: center;
  align-content: center;
  gap: 6px;
  width: 128px;
  height: 128px;
  border: 1px solid var(--line);
  border-radius: 36px;
  background: #fff;
  box-shadow: 0 24px 48px -24px rgb(232 64 47 / 0.35);
}
.hub-core svg {
  width: 52px;
  height: 52px;
}
.hub-core span {
  color: var(--ink);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: -0.01em;
}
.hub-dst li {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  column-gap: 12px;
  padding: 12px 16px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: #fff;
}
.hub-dst li.is-ghost {
  border-style: dashed;
  background: transparent;
}
.hub-dst strong {
  color: var(--ink);
  font-size: 14px;
  font-weight: 500;
}
.hub-dst small {
  grid-row: 2;
  color: var(--ink-4);
  font-size: 12px;
}
.hub-dst em {
  grid-row: 1 / span 2;
  grid-column: 2;
  padding: 2px 10px;
  border-radius: 999px;
  background: rgb(26 26 28 / 0.05);
  color: var(--ink-3);
  font-size: 12px;
  font-style: normal;
}
.hub-dst em.is-live {
  background: color-mix(in oklab, var(--green) 12%, white);
  color: var(--green);
}

/* 卡片底栏：三条原则，竖线分隔 */
.principles {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  margin: 44px -40px 0;
  border-top: 1px solid var(--line);
}
.principles li {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 24px 32px 28px;
}
.principles li + li {
  border-left: 1px solid var(--line);
}
.principles svg {
  flex: none;
  width: 20px;
  height: 20px;
  margin-top: 2px;
  fill: none;
  stroke: var(--ink-2);
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.principles h3 {
  color: var(--ink);
  font-size: 15px;
  font-weight: 500;
}
.principles p {
  margin-top: 2px;
  color: var(--ink-3);
  font-size: 13px;
}

/* 常见问题 */
.faq {
  padding: 0 0 128px;
}
/* 问答卡片：和「关于」的卡片同一种玻璃质感，底栏放联系入口 */
.faq-card {
  margin-top: 48px;
  padding: 8px 40px 0;
  border: 1px solid rgb(255 255 255 / 0.9);
  border-radius: 28px;
  background: rgb(255 255 255 / 0.6);
  box-shadow:
    0 1px 0 rgb(255 255 255 / 0.9) inset,
    0 30px 60px -40px rgb(60 40 30 / 0.25);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}
.faq-foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin: 0 -40px;
  padding: 20px 40px;
  border-top: 1px solid var(--line);
  color: var(--ink-3);
  font-size: 14px;
}
.faq-contact {
  display: inline-flex;
  flex: none;
  align-items: center;
  gap: 8px;
  padding: 9px 18px;
  border-radius: 999px;
  background: var(--ink);
  color: #fff;
  font-size: 14px;
  font-weight: 500;
  transition: background-color 0.3s;
}
.faq-contact i {
  font-style: normal;
  transition: transform 0.3s var(--ease);
}
.faq-contact:hover {
  background: var(--red);
}
.faq-contact:hover i {
  transform: translateX(3px);
}
.faq details:last-child {
  border-bottom: 0;
}
.faq details {
  border-bottom: 1px solid var(--line);
}
.faq summary {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 22px 0;
  color: var(--ink);
  font-size: 16px;
  font-weight: 500;
  list-style: none;
  cursor: pointer;
}
.faq summary::-webkit-details-marker {
  display: none;
}
.q-no {
  flex: none;
  width: 28px;
  color: var(--ink-4);
  font-size: 13px;
  font-weight: 500;
  transition: color 0.3s;
}
.q-text {
  flex: 1;
  transition: color 0.3s;
}
.faq summary:hover .q-text {
  color: var(--red);
}
.q-icon {
  position: relative;
  flex: none;
  width: 28px;
  height: 28px;
  border: 1px solid var(--line);
  border-radius: 50%;
  transition:
    background-color 0.3s,
    border-color 0.3s,
    transform 0.4s var(--ease);
}
.q-icon::before,
.q-icon::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 10px;
  height: 1.5px;
  margin: -0.75px 0 0 -5px;
  background: var(--ink-2);
  transition: background-color 0.3s;
}
.q-icon::after {
  transform: rotate(90deg);
}
.faq details[open] .q-no {
  color: var(--red);
}
.faq details[open] .q-icon {
  border-color: var(--ink);
  background: var(--ink);
  transform: rotate(45deg);
}
.faq details[open] .q-icon::before,
.faq details[open] .q-icon::after {
  background: #fff;
}
.faq details p {
  max-width: 620px;
  padding: 0 48px 26px;
  color: var(--ink-2);
}
.faq details a {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-color: var(--ink-4);
  text-underline-offset: 3px;
}
.faq details a:hover {
  color: var(--red);
  text-decoration-color: currentColor;
}
/* 支持的浏览器里展开收起带高度过渡 */
@supports (interpolate-size: allow-keywords) {
  :root {
    interpolate-size: allow-keywords;
  }
  .faq details::details-content {
    height: 0;
    overflow: hidden;
    transition:
      height 0.45s var(--ease),
      content-visibility 0.45s allow-discrete;
  }
  .faq details[open]::details-content {
    height: auto;
  }
}

/* =============== 页脚（DeepSeek 式多列） =============== */
.footer {
  border-top: 1px solid var(--line);
  padding: 64px 0 32px;
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 48px;
}
.footer-brand p {
  margin-top: 14px;
  color: var(--ink-3);
  font-size: 13px;
}
.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(120px, auto));
  gap: 56px;
}
.footer-cols div {
  display: grid;
  align-content: start;
  gap: 12px;
  font-size: 13px;
}
.footer-cols h2 {
  margin-bottom: 4px;
  color: var(--ink);
  font-size: 13px;
  font-weight: 500;
}
.footer-cols a,
.footer-cols span {
  color: var(--ink-3);
  transition: color 0.2s;
}
.footer-cols a:hover {
  color: var(--ink);
}
.footer-bottom {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--line);
  color: var(--ink-4);
  font-size: 12px;
}

/* =============== 动画 =============== */
/* 全站统一的上浮：位移小、时间短 */
.rv {
  opacity: 0;
  transform: translateY(24px);
  transition:
    opacity 0.8s var(--ease),
    transform 0.8s var(--ease);
  transition-delay: var(--rv-delay, 0s);
}
.rv.is-in {
  opacity: 1;
  transform: none;
}
@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
}
@keyframes caret {
  50% {
    opacity: 0;
  }
}
@keyframes pulse-run {
  from {
    stroke-dashoffset: 100;
  }
  to {
    stroke-dashoffset: 0;
  }
}
@keyframes bob {
  50% {
    transform: translateY(-6px) rotate(-6deg);
  }
}
@keyframes spin {
  to {
    transform: rotate(1turn);
  }
}
@keyframes flow-a {
  0%,
  100% {
    transform: translate(0, 0) scale(1) rotate(0deg);
  }
  33% {
    transform: translate(9vw, 5vw) scale(1.15) rotate(18deg);
  }
  66% {
    transform: translate(3vw, 10vw) scale(0.92) rotate(-12deg);
  }
}
@keyframes flow-b {
  0%,
  100% {
    transform: translate(0, 0) scale(1) rotate(0deg);
  }
  40% {
    transform: translate(-10vw, 7vw) scale(1.12) rotate(-20deg);
  }
  75% {
    transform: translate(-4vw, -3vw) scale(0.95) rotate(10deg);
  }
}
@keyframes flow-c {
  0%,
  100% {
    transform: translate(0, 0) scale(1);
  }
  25% {
    transform: translate(12vw, -4vw) scale(1.2);
  }
  50% {
    transform: translate(4vw, 6vw) scale(0.9);
  }
  75% {
    transform: translate(-8vw, 2vw) scale(1.1);
  }
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  .sky::before,
  .cloud,
  .hero-inner > *,
  .hub-lines path.pulse,
  .type::after {
    animation: none;
  }
  .hub-lines path.pulse {
    display: none;
  }
  .sky {
    transform: none;
  }
}

/* =============== 响应式 =============== */
@media (max-width: 760px) {
  .nav {
    padding: 8px 0 0;
  }
  .nav-bar {
    padding: 4px 6px 4px 12px;
  }
  .nav-bar {
    gap: 16px;
  }
  .nav-links {
    display: none;
  }
  .nav-cta {
    margin-left: auto;
  }
  .hero {
    min-height: auto;
    padding: 112px 0 72px;
  }
  .hero-inner {
    padding: 0 24px;
  }
  .cloud {
    filter: blur(44px);
  }
  .c1 {
    width: 90vw;
    height: 70vw;
  }
  .c2 {
    width: 80vw;
    height: 70vw;
    top: 12%;
  }
  .c3 {
    width: 60vw;
    height: 44vw;
    top: 46%;
  }
  .c5 {
    width: 46vw;
    height: 34vw;
    left: 26%;
  }
  .hero h1 {
    margin-top: 24px;
    font-size: clamp(28px, 8.4vw, 40px);
    --ls: 0.08em;
  }
  .hero-sub {
    font-size: 15px;
  }
  .panel {
    margin-top: 32px;
    border-radius: 20px;
  }
  .panel-search kbd,
  .item-domain {
    display: none;
  }
  .item {
    gap: 12px;
    padding: 12px 10px;
  }
  .item-state {
    min-width: 0;
  }
  .item-go {
    display: none;
  }
  .about {
    padding: 24px 0 80px;
  }
  .manifesto,
  .faq .sec-center h2 {
    font-size: 26px;
  }
  .manifesto br {
    display: inline;
  }
  .sec-sub {
    font-size: 14px;
  }
  .hub {
    margin-top: 36px;
    padding: 28px 20px 0;
  }
  .hub-grid {
    grid-template-columns: 1fr;
    justify-items: center;
    gap: 28px;
  }
  .hub-lines {
    display: none;
  }
  .hub-src {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 8px;
  }
  .hub-src::after,
  .hub-core::after {
    /* 手机上用一根竖线把三层串起来 */
    content: '';
    position: absolute;
    left: 50%;
    bottom: -28px;
    width: 1px;
    height: 28px;
    background: linear-gradient(var(--line), var(--red));
  }
  .hub-core {
    width: 104px;
    height: 104px;
    border-radius: 30px;
  }
  .hub-dst {
    width: 100%;
  }
  .principles {
    grid-template-columns: 1fr;
    margin: 28px -20px 0;
  }
  .principles li {
    padding: 18px 20px;
  }
  .principles li + li {
    border-left: 0;
    border-top: 1px solid var(--line);
  }
  .faq {
    padding-bottom: 88px;
  }
  .faq-card {
    margin-top: 36px;
    padding: 0 20px;
  }
  .faq-foot {
    flex-direction: column;
    align-items: flex-start;
    margin: 0 -20px;
    padding: 18px 20px 20px;
  }
  .faq summary {
    gap: 14px;
    padding: 18px 0;
    font-size: 15px;
  }
  .q-no {
    width: 20px;
  }
  .faq details p {
    padding: 0 0 22px 34px;
  }
  .footer {
    padding: 48px 0 28px;
  }
  .footer-inner {
    flex-direction: column;
    gap: 36px;
  }
  .footer-cols {
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
  }
  .footer-bottom {
    flex-direction: column;
    gap: 6px;
    margin-top: 36px;
  }
}