/* ==========================================================================
   WhatsApp网页版 · 静态官网样式表（纯手写，零第三方依赖）
   作者：本站前端
   配色：品牌绿 + 中性灰白，浅色为主
   ========================================================================== */

/* ---------- 1. 设计变量 ---------- */
:root {
  --brand: #1faf5f;
  --brand-strong: #0f8a4a;
  --brand-deep: #0a3d2c;
  --brand-soft: #e8f7ee;
  --brand-glow: rgba(31, 175, 95, 0.18);

  --ink: #0e211b;
  --ink-2: #24382f;
  --muted: #5d7069;
  --muted-2: #849a92;

  --bg: #ffffff;
  --bg-soft: #f5f9f7;
  --bg-tint: #eff7f3;
  --line: #e2ece7;
  --line-strong: #cfe0d8;

  --warn: #b4690e;
  --warn-bg: #fdf6e9;
  --warn-line: #f0e0c2;

  --radius-sm: 8px;
  --radius: 14px;
  --radius-lg: 22px;
  --shadow-sm: 0 1px 2px rgba(14, 33, 27, 0.05), 0 4px 12px rgba(14, 33, 27, 0.04);
  --shadow: 0 2px 4px rgba(14, 33, 27, 0.04), 0 12px 32px rgba(14, 33, 27, 0.07);
  --shadow-lg: 0 4px 8px rgba(14, 33, 27, 0.05), 0 24px 56px rgba(14, 33, 27, 0.1);

  --maxw: 1160px;
  --header-h: 66px;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Courier New", monospace;
}

/* ---------- 2. 基础重置 ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 16px);
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

a {
  color: var(--brand-strong);
  text-decoration: none;
  transition: color 0.18s ease;
}

a:hover {
  color: var(--brand);
  text-decoration: underline;
  text-underline-offset: 3px;
}

h1,
h2,
h3,
h4 {
  margin: 0 0 0.6em;
  line-height: 1.3;
  color: var(--ink);
  letter-spacing: -0.01em;
  font-weight: 700;
}

h1 {
  font-size: clamp(1.75rem, 3.4vw, 2.7rem);
  letter-spacing: -0.02em;
}

h2 {
  font-size: clamp(1.35rem, 2.2vw, 1.85rem);
}

h3 {
  font-size: 1.15rem;
}

p {
  margin: 0 0 1em;
}

ul,
ol {
  padding-left: 1.35em;
  margin: 0 0 1em;
}

li {
  margin-bottom: 0.4em;
}

strong {
  color: var(--ink);
  font-weight: 600;
}

code {
  font-family: var(--mono);
  font-size: 0.9em;
  background: var(--bg-tint);
  border: 1px solid var(--line);
  border-radius: 5px;
  padding: 0.1em 0.4em;
  color: var(--brand-deep);
}

:focus-visible {
  outline: 3px solid var(--brand);
  outline-offset: 2px;
  border-radius: 4px;
}

::selection {
  background: var(--brand-glow);
  color: var(--brand-deep);
}

/* ---------- 3. 布局工具 ---------- */
.wrap {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 20px;
}

.section {
  padding: 64px 0;
}

.section--soft {
  background: var(--bg-soft);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.section-head {
  max-width: 720px;
  margin-bottom: 36px;
}

.section-head p {
  color: var(--muted);
  margin-bottom: 0;
  font-size: 1.02rem;
}

.eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--brand-strong);
  background: var(--brand-soft);
  border-radius: 999px;
  padding: 4px 12px;
  margin-bottom: 14px;
}

.lead {
  font-size: 1.08rem;
  color: var(--ink-2);
}

.muted {
  color: var(--muted);
}

.grid {
  display: grid;
  gap: 20px;
}

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

.grid-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

/* ---------- 4. 头部导航 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  min-height: var(--header-h);
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--ink);
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.logo:hover {
  color: var(--ink);
  text-decoration: none;
}

.logo-mark {
  width: 32px;
  height: 32px;
  border-radius: 9px;
  background: linear-gradient(145deg, #34d073, var(--brand-strong));
  display: grid;
  place-items: center;
  box-shadow: 0 4px 12px var(--brand-glow);
  flex: 0 0 auto;
}

.logo-mark svg {
  width: 18px;
  height: 18px;
}

.logo small {
  display: block;
  font-size: 0.68rem;
  font-weight: 500;
  color: var(--muted-2);
  letter-spacing: 0.04em;
  line-height: 1;
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 38px;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 10px;
  cursor: pointer;
  padding: 0;
  place-items: center;
}

.nav-toggle span,
.nav-toggle span::before,
.nav-toggle span::after {
  content: "";
  display: block;
  width: 18px;
  height: 2px;
  background: var(--ink);
  border-radius: 2px;
  position: relative;
  transition: transform 0.2s ease;
}

.nav-toggle span::before {
  position: absolute;
  top: -6px;
}

.nav-toggle span::after {
  position: absolute;
  top: 6px;
}

.nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav a {
  display: block;
  padding: 8px 12px;
  border-radius: 9px;
  font-size: 0.93rem;
  font-weight: 500;
  color: var(--ink-2);
  white-space: nowrap;
}

.nav a:hover {
  background: var(--bg-tint);
  color: var(--brand-strong);
  text-decoration: none;
}

.nav a[aria-current="page"] {
  color: var(--brand-strong);
  background: var(--brand-soft);
  font-weight: 600;
}

.header-cta {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 9px 16px;
  border-radius: 999px;
  background: var(--brand);
  color: #fff !important;
  font-size: 0.9rem;
  font-weight: 600;
  box-shadow: 0 4px 14px var(--brand-glow);
  white-space: nowrap;
}

.header-cta:hover {
  background: var(--brand-strong);
  text-decoration: none;
  color: #fff;
}

/* ---------- 5. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 24px;
  border-radius: 999px;
  font-size: 0.98rem;
  font-weight: 600;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.16s ease, background 0.18s ease, box-shadow 0.18s ease,
    color 0.18s ease;
}

.btn:hover {
  text-decoration: none;
  transform: translateY(-1px);
}

.btn:active {
  transform: translateY(0);
}

.btn-primary {
  background: var(--brand);
  color: #fff;
  box-shadow: 0 6px 20px var(--brand-glow);
}

.btn-primary:hover {
  background: var(--brand-strong);
  color: #fff;
  box-shadow: 0 10px 26px rgba(15, 138, 74, 0.28);
}

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

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

.btn-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}

.btn-sm {
  padding: 9px 18px;
  font-size: 0.88rem;
}

/* ---------- 6. 首页 Hero ---------- */
.hero {
  position: relative;
  overflow: hidden;
  padding: 72px 0 64px;
  background: radial-gradient(120% 120% at 12% 0%, #f0faf4 0%, #ffffff 46%),
    linear-gradient(180deg, #ffffff, #f8fcfa);
  border-bottom: 1px solid var(--line);
}

.hero::after {
  content: "";
  position: absolute;
  top: -160px;
  right: -120px;
  width: 520px;
  height: 520px;
  background: radial-gradient(circle, rgba(31, 175, 95, 0.16), transparent 62%);
  pointer-events: none;
}

.hero-inner {
  position: relative;
  display: grid;
  grid-template-columns: 1.08fr 0.92fr;
  gap: 52px;
  align-items: center;
}

.hero h1 span {
  color: var(--brand-strong);
  background: linear-gradient(180deg, transparent 62%, rgba(31, 175, 95, 0.22) 62%);
}

.hero-sub {
  font-size: 1.05rem;
  color: var(--muted);
  max-width: 54ch;
  margin-bottom: 26px;
}

.hero-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 26px;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--ink-2);
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 6px 12px;
  box-shadow: var(--shadow-sm);
}

.badge svg {
  width: 14px;
  height: 14px;
  color: var(--brand-strong);
  flex: 0 0 auto;
}

/* Hero 右侧：模拟浏览器窗口 */
.mock {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}

.mock-bar {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 11px 14px;
  background: var(--bg-soft);
  border-bottom: 1px solid var(--line);
}

.mock-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: #d9e5e0;
}

.mock-url {
  flex: 1;
  margin-left: 6px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 0.72rem;
  color: var(--muted);
  padding: 4px 12px;
  font-family: var(--mono);
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
}

.mock-body {
  padding: 18px;
  background: linear-gradient(180deg, #f9fdfb, #f2f9f5);
}

.mock-row {
  display: flex;
  align-items: center;
  gap: 11px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 11px 13px;
  margin-bottom: 9px;
  box-shadow: var(--shadow-sm);
}

.mock-avatar {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: linear-gradient(145deg, #c9ecdb, #a8ddc3);
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--brand-deep);
}

.mock-lines {
  flex: 1;
  min-width: 0;
}

.mock-line {
  height: 7px;
  border-radius: 4px;
  background: #e6efeb;
  margin-bottom: 6px;
}

.mock-line:last-child {
  margin-bottom: 0;
  width: 62%;
  background: #eef5f1;
}

.mock-line.w70 {
  width: 70%;
}

.mock-line.w45 {
  width: 45%;
}

.mock-time {
  font-size: 0.66rem;
  color: var(--muted-2);
  font-family: var(--mono);
}

/* ---------- 7. 卡片 ---------- */
.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow);
  border-color: var(--line-strong);
}

.card h3 {
  margin-bottom: 8px;
  font-size: 1.06rem;
}

.card p {
  color: var(--muted);
  font-size: 0.94rem;
  margin-bottom: 0;
}

.card-link {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  margin-top: 14px;
  font-size: 0.88rem;
  font-weight: 600;
}

.icon-box {
  width: 42px;
  height: 42px;
  border-radius: 11px;
  background: var(--brand-soft);
  color: var(--brand-strong);
  display: grid;
  place-items: center;
  margin-bottom: 16px;
}

.icon-box svg {
  width: 21px;
  height: 21px;
}

.card--link {
  display: block;
  color: inherit;
  text-decoration: none;
}

.card--link:hover {
  color: inherit;
  text-decoration: none;
}

/* ---------- 8. 面包屑 ---------- */
.crumbs {
  padding: 16px 0 0;
  font-size: 0.82rem;
  color: var(--muted-2);
}

.crumbs ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 0;
  margin: 0;
}

.crumbs li {
  margin: 0;
  display: flex;
  align-items: center;
  gap: 6px;
}

.crumbs li + li::before {
  content: "/";
  color: var(--line-strong);
}

.crumbs a {
  color: var(--muted);
}

.crumbs [aria-current="page"] {
  color: var(--ink-2);
  font-weight: 500;
}

/* ---------- 9. 内页 Hero ---------- */
.page-hero {
  padding: 30px 0 44px;
  background: linear-gradient(180deg, #f6fbf8, #ffffff);
  border-bottom: 1px solid var(--line);
}

.page-hero h1 {
  max-width: 22ch;
  margin-bottom: 14px;
}

.page-hero .lead {
  max-width: 68ch;
  color: var(--muted);
  margin-bottom: 20px;
}

.page-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  font-size: 0.82rem;
  color: var(--muted-2);
}

/* ---------- 10. 步骤列表 ---------- */
.steps {
  counter-reset: step;
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 16px;
}

.steps > li {
  counter-increment: step;
  position: relative;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 22px 22px 68px;
  margin: 0;
  box-shadow: var(--shadow-sm);
}

.steps > li::before {
  content: counter(step);
  position: absolute;
  left: 20px;
  top: 20px;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--brand-soft);
  color: var(--brand-strong);
  font-weight: 700;
  font-size: 0.95rem;
  display: grid;
  place-items: center;
  border: 1px solid rgba(31, 175, 95, 0.25);
}

.steps h3 {
  font-size: 1.02rem;
  margin-bottom: 6px;
}

.steps p {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 0.94rem;
}

.steps p + p {
  margin-top: 8px;
}

/* ---------- 11. 提示框 ---------- */
.notice {
  border: 1px solid var(--warn-line);
  background: var(--warn-bg);
  border-radius: var(--radius);
  padding: 16px 18px 16px 46px;
  position: relative;
  font-size: 0.92rem;
  color: #6b4408;
  margin: 0 0 20px;
}

.notice::before {
  content: "!";
  position: absolute;
  left: 16px;
  top: 16px;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--warn);
  color: #fff;
  font-weight: 700;
  font-size: 0.78rem;
  display: grid;
  place-items: center;
  font-family: var(--mono);
}

.notice p:last-child {
  margin-bottom: 0;
}

.notice--info {
  border-color: #c8e6d7;
  background: var(--brand-soft);
  color: #0c4a30;
}

.notice--info::before {
  content: "i";
  background: var(--brand-strong);
  font-family: var(--mono);
  font-style: italic;
}

/* ---------- 12. 文章正文排版 ---------- */
.prose {
  max-width: 78ch;
}

.prose h2 {
  margin-top: 2em;
  padding-top: 0.2em;
}

.prose h2:first-child {
  margin-top: 0;
}

.prose h3 {
  margin-top: 1.6em;
}

.prose ul,
.prose ol {
  color: var(--ink-2);
}

.prose blockquote {
  margin: 1.4em 0;
  padding: 12px 20px;
  border-left: 3px solid var(--brand);
  background: var(--bg-soft);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--ink-2);
}

.prose blockquote p:last-child {
  margin-bottom: 0;
}

/* 双栏正文 + 侧边目录 */
.layout-aside {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 44px;
  align-items: start;
}

.aside-card {
  position: sticky;
  top: calc(var(--header-h) + 20px);
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px;
}

.aside-card h2 {
  font-size: 0.82rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted-2);
  margin-bottom: 12px;
}

.aside-card ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.aside-card li {
  margin-bottom: 2px;
}

.aside-card a {
  display: block;
  padding: 6px 10px;
  border-radius: 7px;
  font-size: 0.88rem;
  color: var(--ink-2);
}

.aside-card a:hover {
  background: #fff;
  color: var(--brand-strong);
  text-decoration: none;
}

/* ---------- 13. 表格 ---------- */
.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  margin: 0 0 24px;
  background: #fff;
  box-shadow: var(--shadow-sm);
  -webkit-overflow-scrolling: touch;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.93rem;
  min-width: 560px;
}

caption {
  text-align: left;
  padding: 14px 18px 0;
  font-size: 0.82rem;
  color: var(--muted-2);
}

th,
td {
  padding: 13px 18px;
  text-align: left;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}

thead th {
  background: var(--bg-soft);
  font-size: 0.84rem;
  font-weight: 700;
  color: var(--ink-2);
  white-space: nowrap;
}

tbody tr:last-child td {
  border-bottom: 0;
}

tbody tr:hover {
  background: #fbfefc;
}

td strong {
  color: var(--brand-strong);
}

/* ---------- 14. FAQ 手风琴 ---------- */
.faq-list {
  display: grid;
  gap: 10px;
}

.faq-item {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.faq-item[open] {
  border-color: rgba(31, 175, 95, 0.35);
  box-shadow: var(--shadow-sm);
}

.faq-item summary {
  cursor: pointer;
  padding: 16px 48px 16px 20px;
  font-weight: 600;
  font-size: 0.98rem;
  color: var(--ink);
  list-style: none;
  position: relative;
  transition: color 0.18s ease;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary:hover {
  color: var(--brand-strong);
}

.faq-item summary::after {
  content: "";
  position: absolute;
  right: 20px;
  top: 50%;
  width: 9px;
  height: 9px;
  border-right: 2px solid var(--muted-2);
  border-bottom: 2px solid var(--muted-2);
  transform: translateY(-70%) rotate(45deg);
  transition: transform 0.2s ease;
}

.faq-item[open] summary::after {
  transform: translateY(-30%) rotate(225deg);
  border-color: var(--brand-strong);
}

.faq-answer {
  padding: 0 20px 18px;
  color: var(--muted);
  font-size: 0.94rem;
  border-top: 1px solid transparent;
}

.faq-answer p:last-child {
  margin-bottom: 0;
}

/* ---------- 15. CTA 区块 ---------- */
.cta {
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, #0d3b2b, #12513a 55%, #14603f);
  color: #eaf7f0;
  border-radius: var(--radius-lg);
  padding: 48px 42px;
  text-align: center;
}

.cta::after {
  content: "";
  position: absolute;
  inset: auto -80px -140px auto;
  width: 360px;
  height: 360px;
  background: radial-gradient(circle, rgba(52, 208, 115, 0.28), transparent 62%);
  pointer-events: none;
}

.cta h2 {
  color: #fff;
  margin-bottom: 10px;
}

.cta p {
  color: #b6d6c6;
  max-width: 56ch;
  margin: 0 auto 24px;
}

.cta .btn-ghost {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.28);
  color: #fff;
}

.cta .btn-ghost:hover {
  background: rgba(255, 255, 255, 0.16);
  color: #fff;
  border-color: rgba(255, 255, 255, 0.5);
}

/* ---------- 16. 页脚 ---------- */
.site-footer {
  background: #0b1f19;
  color: #9db3aa;
  padding: 52px 0 26px;
  margin-top: 0;
  font-size: 0.9rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 32px;
  padding-bottom: 34px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.site-footer .logo {
  color: #fff;
  margin-bottom: 12px;
}

.site-footer .logo small {
  color: #71938a;
}

.site-footer p {
  margin-bottom: 0;
  max-width: 34ch;
  line-height: 1.7;
}

.footer-col h2 {
  color: #fff;
  font-size: 0.85rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 14px;
}

.footer-col ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-col li {
  margin-bottom: 9px;
}

.footer-col a {
  color: #9db3aa;
  font-size: 0.88rem;
}

.footer-col a:hover {
  color: #4fdc8a;
  text-decoration: none;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
  justify-content: space-between;
  padding-top: 20px;
  font-size: 0.8rem;
  color: #6f8d84;
}

.footer-bottom p {
  max-width: none;
  margin: 0;
}

/* ---------- 17. 返回顶部 ---------- */
.to-top {
  position: fixed;
  right: 20px;
  bottom: 22px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid var(--line-strong);
  background: #fff;
  color: var(--ink-2);
  display: grid;
  place-items: center;
  box-shadow: var(--shadow);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: all 0.22s ease;
  z-index: 90;
  padding: 0;
}

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

.to-top:hover {
  color: var(--brand-strong);
  border-color: var(--brand);
}

.to-top svg {
  width: 18px;
  height: 18px;
}

/* ---------- 18. 对比条 / 数据条 ---------- */
.stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.stat {
  background: #fff;
  padding: 22px 18px;
  text-align: center;
}

.stat b {
  display: block;
  font-size: 1.55rem;
  color: var(--brand-strong);
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.stat span {
  font-size: 0.8rem;
  color: var(--muted-2);
}

/* ---------- 19. 404 ---------- */
.err-page {
  min-height: 62vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 70px 20px;
}

.err-code {
  font-size: clamp(4rem, 14vw, 8rem);
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.05em;
  background: linear-gradient(150deg, var(--brand), var(--brand-deep));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: 10px;
}

/* ---------- 20. 响应式 ---------- */
@media (max-width: 1000px) {
  .hero-inner {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .hero {
    padding: 52px 0 48px;
  }

  .grid-4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .layout-aside {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .aside-card {
    position: static;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 26px;
  }
}

@media (max-width: 860px) {
  .nav-toggle {
    display: grid;
  }

  .nav {
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    background: #fff;
    border-bottom: 1px solid var(--line);
    padding: 10px 16px 16px;
    box-shadow: var(--shadow);
    display: none;
  }

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

  .nav a {
    padding: 12px 12px;
    font-size: 0.96rem;
  }

  .header-cta {
    display: none;
  }

  .grid-3,
  .grid-2 {
    grid-template-columns: 1fr;
  }

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

  .section {
    padding: 48px 0;
  }

  .cta {
    padding: 36px 22px;
  }

  .steps > li {
    padding: 20px 18px 20px 62px;
  }
}

@media (max-width: 560px) {
  .hero-badges .badge {
    font-size: 0.76rem;
    padding: 5px 10px;
  }

  .btn {
    width: 100%;
  }

  .btn-row .btn {
    width: 100%;
  }

  .footer-grid {
    grid-template-columns: 1fr;
  }

  .to-top {
    right: 14px;
    bottom: 14px;
  }
}

/* ---------- 21. 无障碍 / 动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    transition-duration: 0.001ms !important;
  }
}

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

/* ---------- 22. 打印 ---------- */
@media print {
  .site-header,
  .site-footer,
  .to-top,
  .cta,
  .nav-toggle {
    display: none !important;
  }

  body {
    color: #000;
  }

  .card,
  .steps > li,
  .table-wrap {
    box-shadow: none;
    border-color: #ccc;
  }
}