/* ════════════════════════════════════════════════════════
   空灵邮箱官网
   约束：仅黑白灰 · 小圆角 · 细体大字 · 克制的玻璃质感
   ════════════════════════════════════════════════════════ */

/* 自带 Inter 可变字体（拉丁部分），中文回退系统黑体 */
@font-face {
  font-family: 'Inter Local';
  src: url('assets/fonts/inter-var.woff2') format('woff2');
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
}

:root {
  /* 纯黑主调 */
  --bg: #08080a;
  --ink: #f5f5f6;
  --ink-soft: rgba(245, 245, 246, 0.6);
  --ink-faint: rgba(245, 245, 246, 0.36);

  /* 极克制的玻璃层 */
  --surface: rgba(255, 255, 255, 0.032);
  --surface-2: rgba(255, 255, 255, 0.055);
  --line: rgba(255, 255, 255, 0.1);
  --line-soft: rgba(255, 255, 255, 0.06);
  --line-strong: rgba(255, 255, 255, 0.2);

  /* 按钮光扫颜色（深色主题下主按钮是白底，光扫用暗色才看得见） */
  --btn-bg: #f5f5f6;
  --btn-fg: #08080a;
  --btn-sheen: rgba(0, 0, 0, 0.26);

  /* 小圆角 */
  --r-xs: 6px;
  --r-sm: 8px;
  --r-md: 11px;
  --r-lg: 14px;
  --r-xl: 18px;
  --r-pill: 999px;

  --shadow-sm: 0 6px 18px -14px rgba(0, 0, 0, 0.9);
  --shadow: 0 24px 60px -34px rgba(0, 0, 0, 0.95);

  --max: 1240px;
  --gutter: 40px;
  --section-y: 132px;

  color-scheme: dark;
}

:root[data-theme='light'] {
  --bg: #fafafa;
  --ink: #0a0a0b;
  --ink-soft: rgba(10, 10, 11, 0.6);
  --ink-faint: rgba(10, 10, 11, 0.42);

  --surface: rgba(255, 255, 255, 0.72);
  --surface-2: rgba(255, 255, 255, 0.9);
  --line: rgba(10, 10, 11, 0.1);
  --line-soft: rgba(10, 10, 11, 0.06);
  --line-strong: rgba(10, 10, 11, 0.2);

  --btn-bg: #0a0a0b;
  --btn-fg: #ffffff;
  --btn-sheen: rgba(255, 255, 255, 0.4);

  --shadow-sm: 0 6px 16px -14px rgba(10, 10, 11, 0.4);
  --shadow: 0 22px 54px -32px rgba(10, 10, 11, 0.32);

  color-scheme: light;
}

* {
  box-sizing: border-box;
}

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: 'Inter Local', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC',
    'Hiragino Sans GB', 'Microsoft YaHei', 'Noto Sans CJK SC', 'Source Han Sans SC', sans-serif;
  /* 整体字重偏细，标题更细 */
  font-weight: 380;
  font-size: 16px;
  line-height: 1.7;
  letter-spacing: -0.005em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  font-synthesis-weight: none;
}

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

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

h1,
h2,
h3,
h4 {
  font-weight: 300;
}

code,
pre {
  font-family: 'JetBrains Mono', 'SFMono-Regular', Consolas, Menlo, monospace;
  font-size: 0.88em;
}

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

::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  border: 4px solid transparent;
  border-radius: var(--r-pill);
  background: var(--line-strong);
  background-clip: content-box;
}

/* ── 背景氛围 ─────────────────────────────────────────── */
.glow {
  position: fixed;
  z-index: 0;
  border-radius: 50%;
  filter: blur(140px);
  pointer-events: none;
  opacity: 0.42;
}

.glow-a {
  width: 720px;
  height: 720px;
  top: -340px;
  left: -180px;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.09), transparent 66%);
}

.glow-b {
  width: 600px;
  height: 600px;
  top: 40%;
  right: -280px;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.055), transparent 68%);
}

:root[data-theme='light'] .glow-a {
  background: radial-gradient(circle, rgba(10, 10, 11, 0.05), transparent 64%);
}

:root[data-theme='light'] .glow-b {
  background: radial-gradient(circle, rgba(10, 10, 11, 0.035), transparent 66%);
}

.grid-bg {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image: linear-gradient(var(--line-soft) 1px, transparent 1px),
    linear-gradient(90deg, var(--line-soft) 1px, transparent 1px);
  background-size: 84px 84px;
  -webkit-mask-image: radial-gradient(ellipse 120% 52% at 50% 0%, #000 22%, transparent 72%);
  mask-image: radial-gradient(ellipse 120% 52% at 50% 0%, #000 22%, transparent 72%);
}

/* ── 公告条 ───────────────────────────────────────────── */
.announce {
  position: relative;
  z-index: 2;
  border-bottom: 1px solid var(--line-soft);
}

.announce-inner {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  max-width: var(--max);
  margin: 0 auto;
  padding: 8px var(--gutter);
  font-size: 12.5px;
  color: var(--ink-faint);
}

.announce-tag {
  padding: 1px 8px;
  border: 1px solid var(--line);
  border-radius: var(--r-xs);
  color: var(--ink);
  font-size: 11px;
  font-weight: 500;
}

.announce a {
  color: var(--ink);
  transition: opacity 0.2s ease;
}

.announce a:hover {
  opacity: 0.6;
}

/* ── 导航 ─────────────────────────────────────────────── */
.nav {
  position: sticky;
  top: 0;
  z-index: 60;
  display: flex;
  align-items: center;
  gap: 24px;
  max-width: var(--max);
  margin: 0 auto;
  padding: 14px var(--gutter);
  transition: background 0.4s ease, box-shadow 0.4s ease;
}

.nav.is-scrolled {
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(20px) saturate(150%);
  -webkit-backdrop-filter: blur(20px) saturate(150%);
  box-shadow: 0 1px 0 var(--line-soft);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: var(--r-sm);
  background: var(--ink);
  color: var(--bg);
}

.brand-text {
  font-size: 15px;
  font-weight: 480;
  letter-spacing: -0.01em;
}

.nav-links {
  display: flex;
  gap: 2px;
  margin-left: auto;
}

.nav-links a {
  padding: 7px 13px;
  border-radius: var(--r-xs);
  color: var(--ink-soft);
  font-size: 14px;
  transition: color 0.2s ease, background 0.2s ease;
}

.nav-links a:hover {
  color: var(--ink);
  background: var(--surface);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 14px;
}

.nav-src {
  font-size: 14px;
  color: var(--ink-soft);
  transition: color 0.2s ease;
}

.nav-src:hover {
  color: var(--ink);
}

.icon-btn {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: var(--r-sm);
  border: 1px solid var(--line-soft);
  background: transparent;
  color: var(--ink-soft);
  cursor: pointer;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.icon-btn:hover {
  color: var(--ink);
  border-color: var(--line);
}

.icon-btn .ico-sun {
  display: none;
}

:root[data-theme='light'] .icon-btn .ico-sun {
  display: block;
}

:root[data-theme='light'] .icon-btn .ico-moon {
  display: none;
}

.nav-toggle {
  display: none;
  width: 34px;
  height: 34px;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-sm);
  background: transparent;
  cursor: pointer;
  position: relative;
  padding: 0;
}

.nav-toggle span {
  position: absolute;
  left: 10px;
  width: 14px;
  height: 1.5px;
  background: var(--ink);
}

.nav-toggle span:first-child {
  top: 13px;
}

.nav-toggle span:last-child {
  top: 19px;
}

/* ── 按钮：小巧、小圆角、hover 光扫 ───────────────────── */
.btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  padding: 8px 16px;
  border-radius: var(--r-sm);
  border: 1px solid transparent;
  font-size: 13.5px;
  font-weight: 460;
  letter-spacing: -0.005em;
  cursor: pointer;
  white-space: nowrap;
  overflow: hidden;
  transition: transform 0.22s ease, opacity 0.22s ease, border-color 0.22s ease,
    background 0.22s ease;
}

.btn-block {
  width: 100%;
}

/* 光带：默认藏在左侧，hover 时从左边扫过 */
.btn::after {
  content: '';
  position: absolute;
  top: -10%;
  left: 0;
  width: 42%;
  height: 120%;
  background: linear-gradient(100deg, transparent, var(--btn-sheen), transparent);
  transform: translateX(-180%) skewX(-20deg);
  pointer-events: none;
}

.btn:hover::after {
  transform: translateX(320%) skewX(-20deg);
  transition: transform 0.72s cubic-bezier(0.33, 0, 0.2, 1);
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--btn-bg);
  color: var(--btn-fg);
  border-color: transparent;
}

.btn-ghost {
  background: transparent;
  border-color: var(--line);
  color: var(--ink);
}

.btn-ghost:hover {
  border-color: var(--line-strong);
  background: var(--surface);
}

/* 文字型 CTA：无按钮外观，hover 浮起 + 下划线展开 */
.cta {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 4px 0;
  font-size: 16.5px;
  font-weight: 440;
  letter-spacing: -0.015em;
  transition: transform 0.34s cubic-bezier(0.22, 1, 0.36, 1), opacity 0.25s ease;
}

.cta::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s cubic-bezier(0.22, 1, 0.36, 1);
}

.cta:hover {
  transform: translateY(-3px);
}

.cta:hover::after {
  transform: scaleX(1);
}

.cta svg {
  transition: transform 0.34s cubic-bezier(0.22, 1, 0.36, 1);
}

.cta:hover svg {
  transform: translateX(4px);
}

.cta-quiet {
  color: var(--ink-soft);
  font-weight: 380;
}

.cta-quiet:hover {
  color: var(--ink);
}

/* ── Hero：左对齐、超大、细体 ─────────────────────────── */
.hero {
  position: relative;
  z-index: 1;
  max-width: var(--max);
  margin: 0 auto;
  padding: 108px var(--gutter) 92px;
}

.hero-inner {
  max-width: 100%;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  margin-bottom: 34px;
  padding: 6px 14px 6px 11px;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-pill);
  font-size: 12.5px;
  color: var(--ink-soft);
}

.pill .dot {
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--ink);
  opacity: 0.7;
}

.hero h1 {
  margin: 0 0 32px;
  /* 一进页面就占满整屏的感受：字号随视口放大 */
  font-size: clamp(46px, 10.4vw, 168px);
  line-height: 0.95;
  letter-spacing: -0.055em;
  font-weight: 250;
}

.hero h1 em {
  font-style: normal;
  color: var(--ink-faint);
}

.lede {
  margin: 0 0 44px;
  max-width: 40em;
  font-size: 17.5px;
  line-height: 1.75;
  color: var(--ink-soft);
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 30px;
}

/* ── 横向轮播（幻灯片） ───────────────────────────────── */
.marquee {
  position: relative;
  overflow: hidden;
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 5%, #000 95%, transparent);
  mask-image: linear-gradient(90deg, transparent, #000 5%, #000 95%, transparent);
}

.marquee-track {
  display: flex;
  gap: 20px;
  width: max-content;
  will-change: transform;
  animation: marquee-slide 60s linear infinite;
}

.marquee.is-reverse .marquee-track {
  animation-direction: reverse;
}

.marquee:hover .marquee-track {
  animation-play-state: paused;
}

@keyframes marquee-slide {
  to {
    transform: translateX(-50%);
  }
}

/* 截图轮播 */
.shots {
  position: relative;
  z-index: 1;
  padding: 0 0 var(--section-y);
}

.shots-head {
  max-width: var(--max);
  margin: 0 auto 44px;
  padding: 0 var(--gutter);
}

.shots-head h2 {
  margin: 0 0 10px;
  font-size: clamp(28px, 3.4vw, 42px);
  letter-spacing: -0.04em;
}

.shots-head p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 16px;
}

.shots-marquee {
  padding: 0 var(--gutter);
}

.shot {
  flex: 0 0 auto;
  width: min(660px, 76vw);
  margin: 0;
}

.shot img {
  width: 100%;
  height: auto;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-lg);
  background: var(--surface);
  transition: transform 0.45s cubic-bezier(0.22, 1, 0.36, 1), border-color 0.3s ease;
}

.shot:hover img {
  transform: translateY(-4px) scale(1.008);
  border-color: var(--line);
}

/* 状态栏说明 */
.tray-note {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 26px;
  max-width: var(--max);
  margin: 46px auto 0;
  padding: 0 var(--gutter);
}

.tray-shot {
  flex: 0 0 auto;
  padding: 14px 18px;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-lg);
  background: var(--surface);
}

.tray-shot img {
  width: min(420px, 62vw);
  height: auto;
  border-radius: var(--r-xs);
}

.tray-note p {
  flex: 1 1 320px;
  margin: 0;
  max-width: 46em;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--ink-soft);
}

.tray-note b {
  color: var(--ink);
  font-weight: 560;
}

/* ── 关键数据 ─────────────────────────────────────────── */
.metrics {
  position: relative;
  z-index: 1;
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.metrics-inner {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  border-top: 1px solid var(--line-soft);
  border-bottom: 1px solid var(--line-soft);
}

.metric {
  padding: 34px 24px;
  border-right: 1px solid var(--line-soft);
}

.metric:last-child {
  border-right: none;
}

.metric b {
  display: block;
  font-size: clamp(32px, 3.6vw, 48px);
  font-weight: 260;
  letter-spacing: -0.05em;
  line-height: 1.05;
}

.metric b small {
  font-size: 0.48em;
  font-weight: 300;
  color: var(--ink-faint);
}

.metric span {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  color: var(--ink-faint);
}

/* ── 区块骨架 ─────────────────────────────────────────── */
.section {
  position: relative;
  z-index: 1;
  max-width: var(--max);
  margin: 0 auto;
  padding: var(--section-y) var(--gutter);
}

.section-alt {
  max-width: none;
  border-top: 1px solid var(--line-soft);
  border-bottom: 1px solid var(--line-soft);
  background: color-mix(in srgb, var(--ink) 2.5%, transparent);
}

.section-alt > * {
  max-width: var(--max);
  margin-left: auto;
  margin-right: auto;
}

.section-head {
  max-width: 700px;
  margin-bottom: 60px;
}

.section-head h2 {
  margin: 0 0 14px;
  font-size: clamp(28px, 3.6vw, 48px);
  line-height: 1.14;
  letter-spacing: -0.045em;
}

.section-head p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 16.5px;
  line-height: 1.75;
}

/* ── 能力芯片卡：纯文字 + 关键字加粗 ──────────────────── */
.chips-marquee {
  margin-bottom: 20px;
}

.chips-marquee:last-child {
  margin-bottom: 0;
}

.chip {
  flex: 0 0 auto;
  width: 330px;
  padding: 26px 26px 24px;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-lg);
  background: var(--surface);
  transition: border-color 0.3s ease, background 0.3s ease;
}

.chip:hover {
  border-color: var(--line);
  background: var(--surface-2);
}

.chip h4 {
  margin: 0 0 10px;
  font-size: 16px;
  font-weight: 500;
  letter-spacing: -0.02em;
}

.chip p {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--ink-soft);
}

.chip b {
  color: var(--ink);
  font-weight: 620;
}

/* ── 解决方案 ─────────────────────────────────────────── */
.solutions {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1px;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-lg);
  background: var(--line-soft);
  overflow: hidden;
}

.solution {
  padding: 40px 34px 36px;
  background: var(--bg);
  transition: background 0.35s ease;
}

.solution:hover {
  background: color-mix(in srgb, var(--ink) 3%, var(--bg));
}

.solution-kicker {
  display: inline-block;
  margin-bottom: 20px;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--ink-faint);
}

.solution.is-major .solution-kicker {
  color: var(--ink);
}

.solution h3 {
  margin: 0 0 12px;
  font-size: 20px;
  font-weight: 400;
  letter-spacing: -0.03em;
  line-height: 1.35;
}

.solution > p {
  margin: 0 0 22px;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--ink-soft);
}

.solution ul {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.solution li {
  position: relative;
  padding-left: 18px;
  font-size: 13.5px;
  color: var(--ink-soft);
}

.solution li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 1px;
  background: var(--ink-faint);
}

/* ── 技术栈（描述列表，取代图标网格） ─────────────────── */
.stack-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 0;
  margin: 0;
  border-top: 1px solid var(--line-soft);
}

.stack-list > div {
  display: flex;
  align-items: baseline;
  gap: 18px;
  padding: 20px 4px;
  border-bottom: 1px solid var(--line-soft);
}

.stack-list dt {
  flex: 0 0 108px;
  font-size: 13px;
  color: var(--ink-faint);
}

.stack-list dd {
  margin: 0;
  font-size: 15px;
  font-weight: 420;
}

/* ── 隐私区块 ─────────────────────────────────────────── */
.split {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
  gap: 64px;
  align-items: center;
}

.split-copy h2 {
  margin: 0 0 16px;
  font-size: clamp(28px, 3.4vw, 44px);
  line-height: 1.15;
  letter-spacing: -0.045em;
}

.split-copy > p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 16.5px;
  line-height: 1.78;
}

.checks {
  margin: 32px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 14px;
}

.checks li {
  position: relative;
  padding-left: 26px;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--ink-soft);
}

.checks li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 11px;
  width: 14px;
  height: 1px;
  background: var(--ink);
  opacity: 0.5;
}

.code-card {
  border: 1px solid var(--line-soft);
  border-radius: var(--r-lg);
  background: var(--surface);
  overflow: hidden;
}

.code-head {
  padding: 12px 16px;
  border-bottom: 1px solid var(--line-soft);
  font-size: 12px;
  color: var(--ink-faint);
}

.code-card pre {
  margin: 0;
  padding: 20px;
  overflow-x: auto;
  font-size: 13px;
  line-height: 1.95;
}

.code-card .c {
  color: var(--ink-faint);
}

/* ── 下载 ─────────────────────────────────────────────── */
.download-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
}

.dl-card {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 32px 30px;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-lg);
  background: var(--surface);
  transition: border-color 0.3s ease;
}

.dl-card:hover {
  border-color: var(--line);
}

.dl-card.is-featured {
  border-color: var(--line-strong);
}

.dl-head {
  display: flex;
  align-items: center;
  gap: 12px;
}

.dl-head h3 {
  margin: 0;
  font-size: 19px;
  font-weight: 420;
  letter-spacing: -0.025em;
}

.tag {
  padding: 2px 9px;
  border-radius: var(--r-xs);
  background: var(--ink);
  color: var(--bg);
  font-size: 11px;
  font-weight: 520;
}

.tag-quiet {
  background: transparent;
  border: 1px solid var(--line);
  color: var(--ink-faint);
  font-weight: 400;
}

.dl-card > p {
  margin: 0;
  font-size: 14.5px;
  color: var(--ink-soft);
}

.cmd {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 11px 13px;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-sm);
  background: color-mix(in srgb, var(--ink) 4%, transparent);
}

.cmd code {
  flex: 1;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  color: var(--ink-soft);
  font-size: 12.5px;
}

.copy {
  flex-shrink: 0;
  padding: 5px 11px;
  border-radius: var(--r-xs);
  border: 1px solid var(--line);
  background: transparent;
  color: var(--ink-soft);
  font-size: 12px;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease;
}

.copy:hover {
  background: var(--ink);
  color: var(--bg);
}

.ver-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.ver-list li {
  display: flex;
  align-items: baseline;
  gap: 14px;
  font-size: 13.5px;
  color: var(--ink-soft);
}

.ver-list b {
  color: var(--ink);
  font-weight: 520;
  min-width: 58px;
}

.ver-list a {
  color: var(--ink-soft);
  border-bottom: 1px solid var(--line-soft);
  transition: color 0.2s ease, border-color 0.2s ease;
}

.ver-list a:hover {
  color: var(--ink);
  border-color: var(--ink);
}

.dl-foot {
  margin: 30px 0 0;
  font-size: 13.5px;
  color: var(--ink-faint);
}

.dl-foot code {
  padding: 2px 7px;
  border-radius: var(--r-xs);
  border: 1px solid var(--line-soft);
  color: var(--ink-soft);
}

/* ── 上手步骤 ─────────────────────────────────────────── */
.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 0;
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line-soft);
}

.steps li {
  padding: 34px 30px 34px 0;
  border-right: 1px solid var(--line-soft);
}

.steps li:last-child {
  border-right: none;
}

.step-no {
  display: block;
  margin-bottom: 16px;
  font-size: 13px;
  color: var(--ink-faint);
  letter-spacing: 0.14em;
}

.steps h3 {
  margin: 0 0 10px;
  font-size: 18px;
  font-weight: 420;
  letter-spacing: -0.025em;
}

.steps p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--ink-soft);
}

.steps strong {
  color: var(--ink);
  font-weight: 560;
}

/* ── 页脚 ─────────────────────────────────────────────── */
.footer {
  position: relative;
  z-index: 1;
  max-width: var(--max);
  margin: 0 auto;
  padding: 72px var(--gutter) 44px;
}

.footer-cols {
  display: grid;
  grid-template-columns: minmax(0, 1.7fr) repeat(3, minmax(0, 1fr));
  gap: 40px;
  padding-bottom: 44px;
  border-bottom: 1px solid var(--line-soft);
}

.footer-col {
  display: flex;
  flex-direction: column;
  gap: 11px;
}

.footer-col > b {
  margin-bottom: 4px;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.1em;
  color: var(--ink-faint);
}

.footer-col a,
.footer-col p {
  font-size: 13.5px;
  color: var(--ink-soft);
  transition: color 0.2s ease;
}

.footer-col a:hover {
  color: var(--ink);
}

.footer-col.is-brand p {
  max-width: 34em;
  line-height: 1.75;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 11px;
}

.footer-brand b {
  font-size: 15.5px;
  font-weight: 460;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  justify-content: space-between;
  padding-top: 26px;
  font-size: 12.5px;
  color: var(--ink-faint);
}

/* ── 进场动画 ─────────────────────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.8s cubic-bezier(0.22, 1, 0.36, 1),
    transform 0.8s cubic-bezier(0.22, 1, 0.36, 1);
}

.reveal.is-visible {
  opacity: 1;
  transform: none;
}

.no-js .reveal {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .marquee-track {
    animation: none;
  }

  html {
    scroll-behavior: auto;
  }
}

/* ── 响应式 ───────────────────────────────────────────── */
@media (max-width: 1080px) {
  :root {
    --section-y: 100px;
    --gutter: 28px;
  }

  .hero {
    padding: 76px var(--gutter) 72px;
  }

  .split {
    grid-template-columns: 1fr;
    gap: 40px;
  }
}

@media (max-width: 880px) {
  .nav {
    position: relative;
  }

  .nav-links {
    position: absolute;
    top: 100%;
    right: var(--gutter);
    left: var(--gutter);
    flex-direction: column;
    gap: 2px;
    padding: 12px;
    border: 1px solid var(--line);
    border-radius: var(--r-lg);
    background: color-mix(in srgb, var(--bg) 96%, var(--ink));
    box-shadow: var(--shadow);
    display: none;
  }

  .nav.is-open .nav-links {
    display: flex;
  }

  .nav-toggle {
    display: block;
    margin-left: auto;
  }

  .nav-src {
    display: none;
  }

  .metrics-inner {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .metric:nth-child(2) {
    border-right: none;
  }

  .metric:nth-child(1),
  .metric:nth-child(2) {
    border-bottom: 1px solid var(--line-soft);
  }

  .steps li {
    border-right: none;
    border-bottom: 1px solid var(--line-soft);
    padding-right: 0;
  }
}

@media (max-width: 760px) {
  :root {
    --section-y: 76px;
    --gutter: 20px;
  }

  .hero {
    padding: 52px var(--gutter) 48px;
  }

  .hero h1 {
    font-size: clamp(38px, 12.5vw, 62px);
  }

  .footer-cols {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 28px;
  }

  .footer-col.is-brand {
    grid-column: 1 / -1;
  }

  .chip {
    width: 280px;
  }

  .shot {
    width: 84vw;
  }

  .announce-inner {
    flex-wrap: wrap;
    text-align: center;
    font-size: 12px;
  }
}

@media (max-width: 480px) {
  .metrics-inner {
    grid-template-columns: 1fr;
  }

  .metric {
    border-right: none;
    border-bottom: 1px solid var(--line-soft);
  }

  .hero-cta {
    gap: 20px;
  }
}