/* ==========================================================================
   whatsapp网页版 · 站点样式（零外部依赖）
   ========================================================================== */

:root {
  --green: #25d366;
  --green-hover: #1fb959;
  --green-dark: #128c7e;
  --teal: #075e54;
  --teal-deep: #054640;
  --bg: #f0f2f5;
  --white: #ffffff;
  --ink: #111b21;
  --ink-2: #4a5c66;
  --ink-3: #667781;
  --line: #e3e7ea;
  --line-soft: #eef1f3;
  --bubble-out: #d9fdd3;
  --shadow-sm: 0 1px 2px rgba(11, 20, 26, .06), 0 2px 8px rgba(11, 20, 26, .04);
  --shadow-md: 0 4px 12px rgba(11, 20, 26, .07), 0 12px 32px rgba(11, 20, 26, .06);
  --shadow-lg: 0 18px 50px rgba(4, 43, 38, .18);
  --r-sm: 8px;
  --r-md: 14px;
  --r-lg: 20px;
  --wrap: 1140px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 84px;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.78;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

img, svg { max-width: 100%; vertical-align: middle; }
a { color: var(--green-dark); text-decoration: none; }
a:hover { color: var(--green-hover); text-decoration: underline; }

h1, h2, h3, h4 {
  margin: 0 0 .6em;
  line-height: 1.35;
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--ink);
  text-wrap: balance;
}
h1 { font-size: clamp(1.75rem, 1.2rem + 2.1vw, 2.75rem); }
h2 { font-size: clamp(1.4rem, 1.1rem + 1.1vw, 1.9rem); }
h3 { font-size: 1.18rem; }
p { margin: 0 0 1.1em; }
ul, ol { margin: 0 0 1.2em; padding-left: 1.35em; }
li { margin-bottom: .45em; }
strong { font-weight: 700; color: #0b1a20; }

.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 20px;
}

.nb { white-space: nowrap; }

.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;
}

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: var(--teal);
  transition: box-shadow .25s ease;
}
.site-header.is-stuck { box-shadow: 0 6px 24px rgba(4, 43, 38, .28); }

.nav-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  height: 68px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  font-weight: 700;
  font-size: 1.06rem;
  letter-spacing: .2px;
  white-space: nowrap;
}
.brand:hover { color: #fff; text-decoration: none; }
.brand-mark {
  display: grid;
  place-items: center;
  width: 34px; height: 34px;
  border-radius: 10px;
  background: var(--green);
  color: var(--teal);
  flex: 0 0 auto;
}
.brand-mark svg { width: 20px; height: 20px; }
.brand small {
  display: block;
  font-size: .68rem;
  font-weight: 500;
  color: rgba(255, 255, 255, .62);
  letter-spacing: .5px;
  line-height: 1.2;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 4px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.nav-list li { margin: 0; }
.nav-list a {
  display: block;
  padding: 8px 13px;
  border-radius: 999px;
  color: rgba(255, 255, 255, .84);
  font-size: .93rem;
  font-weight: 500;
  transition: background .18s, color .18s;
}
.nav-list a:hover,
.nav-list a[aria-current="page"] {
  background: rgba(255, 255, 255, .14);
  color: #fff;
  text-decoration: none;
}

.nav-cta {
  margin-left: 8px;
  padding: 9px 18px !important;
  background: var(--green) !important;
  color: var(--teal) !important;
  font-weight: 700 !important;
}
.nav-cta:hover { background: #2ee06f !important; }

.nav-toggle {
  display: none;
  width: 42px; height: 42px;
  padding: 0;
  border: 1px solid rgba(255, 255, 255, .22);
  border-radius: 10px;
  background: transparent;
  cursor: pointer;
  color: #fff;
}
.nav-toggle svg { width: 22px; height: 22px; }

/* ---------- 通用区块 ---------- */
.section { padding: 66px 0; }
.section--tight { padding: 44px 0; }
.section--white { background: var(--white); }
.section--soft { background: #e9eef1; }

.sec-head { max-width: 720px; margin-bottom: 34px; }
.sec-head.center { margin-left: auto; margin-right: auto; text-align: center; }
.eyebrow {
  display: inline-block;
  margin-bottom: 12px;
  padding: 5px 13px;
  border-radius: 999px;
  background: rgba(37, 211, 102, .14);
  color: var(--green-dark);
  font-size: .78rem;
  font-weight: 700;
  letter-spacing: .6px;
  text-transform: uppercase;
}
.sec-head p { color: var(--ink-2); margin-bottom: 0; }

.rule {
  width: 46px;
  height: 4px;
  margin: 0 0 18px;
  border-radius: 4px;
  background: var(--green);
}
.center .rule { margin-left: auto; margin-right: auto; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 13px 26px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-family: inherit;
  font-size: .98rem;
  font-weight: 700;
  line-height: 1.2;
  cursor: pointer;
  transition: transform .16s, background .18s, box-shadow .18s;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn svg { width: 18px; height: 18px; }

.btn--primary {
  background: var(--green);
  color: #063b33;
  box-shadow: 0 8px 22px rgba(37, 211, 102, .32);
}
.btn--primary:hover { background: #2ee06f; color: #063b33; }

.btn--ghost {
  background: transparent;
  border-color: rgba(255, 255, 255, .4);
  color: #fff;
}
.btn--ghost:hover { background: rgba(255, 255, 255, .12); color: #fff; }

.btn--line {
  background: #fff;
  border-color: var(--line);
  color: var(--ink);
}
.btn--line:hover { border-color: var(--green); color: var(--green-dark); }

.btn-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 26px; }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  overflow: hidden;
  padding: 74px 0 84px;
  background:
    radial-gradient(circle at 78% 12%, rgba(37, 211, 102, .22), transparent 46%),
    linear-gradient(158deg, #075e54 0%, #054640 52%, #043a35 100%);
  color: #fff;
}
.hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 1px;
  background: rgba(7, 94, 84, .18);
  pointer-events: none;
}
.hero h1 { color: #fff; margin-bottom: .45em; }
.hero h1 em {
  font-style: normal;
  color: var(--green);
  background: linear-gradient(transparent 62%, rgba(37, 211, 102, .22) 62%);
}
.hero .eyebrow {
  background: rgba(37, 211, 102, .18);
  color: #8ef0b0;
}
.hero .lead {
  max-width: 600px;
  color: rgba(255, 255, 255, .82);
  font-size: 1.06rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.06fr .94fr;
  gap: 54px;
  align-items: center;
}

.hero-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 26px;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
}
.hero-facts li {
  display: flex;
  align-items: center;
  gap: 7px;
  margin: 0;
  color: rgba(255, 255, 255, .78);
  font-size: .9rem;
}
.hero-facts svg { width: 16px; height: 16px; color: var(--green); flex: 0 0 auto; }

/* 聊天窗口模拟 */
.chat-demo {
  position: relative;
  border-radius: 18px;
  overflow: hidden;
  background: #efeae2;
  box-shadow: var(--shadow-lg);
  border: 1px solid rgba(255, 255, 255, .12);
}
.chat-demo__bar {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 11px 14px;
  background: var(--teal);
  color: #fff;
}
.chat-demo__avatar {
  display: grid;
  place-items: center;
  width: 32px; height: 32px;
  border-radius: 50%;
  background: var(--green);
  color: var(--teal);
  font-size: .78rem;
  font-weight: 800;
  flex: 0 0 auto;
}
.chat-demo__who { font-size: .86rem; font-weight: 600; line-height: 1.3; }
.chat-demo__who span {
  display: block;
  font-size: .7rem;
  font-weight: 400;
  color: rgba(255, 255, 255, .66);
}
.chat-demo__body {
  display: flex;
  flex-direction: column;
  gap: 9px;
  padding: 18px 14px 22px;
  background-image:
    radial-gradient(rgba(7, 94, 84, .045) 1px, transparent 1px);
  background-size: 18px 18px;
}
.bubble {
  max-width: 82%;
  padding: 8px 12px;
  border-radius: 10px;
  background: #fff;
  font-size: .86rem;
  line-height: 1.55;
  color: #111b21;
  box-shadow: 0 1px 1px rgba(11, 20, 26, .09);
}
.bubble--out {
  align-self: flex-end;
  background: var(--bubble-out);
  border-top-right-radius: 3px;
}
.bubble--in { border-top-left-radius: 3px; }
.bubble time {
  display: block;
  margin-top: 2px;
  font-size: .66rem;
  color: #667781;
  text-align: right;
}

/* ---------- 卡片网格 ---------- */
.grid {
  display: grid;
  gap: 20px;
}
.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }

.card {
  padding: 26px 24px;
  background: var(--white);
  border: 1px solid var(--line-soft);
  border-radius: var(--r-md);
  box-shadow: var(--shadow-sm);
  transition: transform .2s, box-shadow .2s, border-color .2s;
}
.card h3 { margin-bottom: .5em; font-size: 1.08rem; }
.card p:last-child { margin-bottom: 0; }
.card p { color: var(--ink-2); font-size: .95rem; }
.card--hover:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: rgba(37, 211, 102, .35);
}
.card--link { display: block; color: inherit; }
.card--link:hover { text-decoration: none; }

.icon-badge {
  display: grid;
  place-items: center;
  width: 46px; height: 46px;
  margin-bottom: 16px;
  border-radius: 12px;
  background: rgba(37, 211, 102, .14);
  color: var(--green-dark);
}
.icon-badge svg { width: 23px; height: 23px; }

.more {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 4px;
  font-size: .9rem;
  font-weight: 600;
}
.more svg { width: 15px; height: 15px; }

/* ---------- 步骤 ---------- */
.steps {
  counter-reset: step;
  display: grid;
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.steps > li {
  counter-increment: step;
  position: relative;
  margin: 0;
  padding: 22px 24px 22px 74px;
  background: var(--white);
  border: 1px solid var(--line-soft);
  border-radius: var(--r-md);
  box-shadow: var(--shadow-sm);
}
.steps > li::before {
  content: counter(step);
  position: absolute;
  top: 20px; left: 22px;
  display: grid;
  place-items: center;
  width: 34px; height: 34px;
  border-radius: 50%;
  background: var(--green);
  color: #063b33;
  font-size: .95rem;
  font-weight: 800;
}
.steps h3 { margin-bottom: .35em; font-size: 1.04rem; }
.steps p { margin-bottom: 0; color: var(--ink-2); font-size: .95rem; }

/* ---------- 文章正文 ---------- */
.article {
  padding: 44px 48px;
  background: var(--white);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--line-soft);
}
.article > h2 {
  margin-top: 2em;
  padding-top: .2em;
}
.article > h2:first-of-type { margin-top: 0; }
.article h3 { margin-top: 1.7em; }
.article p, .article li { color: #29363d; }
.article ul, .article ol { padding-left: 1.4em; }

.article .callout {
  margin: 26px 0;
  padding: 18px 22px;
  border-left: 4px solid var(--green);
  border-radius: 0 var(--r-sm) var(--r-sm) 0;
  background: #f4fbf6;
  font-size: .95rem;
}
.article .callout p:last-child { margin-bottom: 0; }
.article .callout strong { color: var(--green-dark); }

.layout-aside {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 288px;
  gap: 30px;
  align-items: start;
}
.layout-aside > aside { align-self: stretch; }

.aside-card {
  position: sticky;
  top: 92px;
  padding: 22px;
  background: var(--white);
  border: 1px solid var(--line-soft);
  border-radius: var(--r-md);
  box-shadow: var(--shadow-sm);
}
.aside-card h2 {
  margin-bottom: .7em;
  font-size: .84rem;
  letter-spacing: .8px;
  text-transform: uppercase;
  color: var(--ink-3);
}
.aside-card ul { margin: 0; padding: 0; list-style: none; }
.aside-card li { margin-bottom: 2px; }
.aside-card a {
  display: block;
  padding: 7px 10px;
  border-radius: 8px;
  color: var(--ink-2);
  font-size: .92rem;
}
.aside-card a:hover {
  background: #f4fbf6;
  color: var(--green-dark);
  text-decoration: none;
}

/* ---------- 表格 ---------- */
.table-wrap {
  overflow-x: auto;
  margin: 24px 0;
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  background: #fff;
}
table {
  width: 100%;
  border-collapse: collapse;
  font-size: .93rem;
}
th, td {
  padding: 13px 16px;
  text-align: left;
  border-bottom: 1px solid var(--line-soft);
  vertical-align: top;
}
th {
  background: #f6f9fa;
  font-weight: 700;
  color: var(--ink);
  white-space: nowrap;
}
tbody tr:last-child td { border-bottom: 0; }
tbody tr:hover { background: #fafcfc; }

/* ---------- FAQ 折叠 ---------- */
.faq-list { display: grid; gap: 12px; }
.faq-item {
  background: var(--white);
  border: 1px solid var(--line-soft);
  border-radius: var(--r-md);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}
.faq-item summary {
  position: relative;
  padding: 19px 56px 19px 22px;
  font-size: 1rem;
  font-weight: 600;
  color: var(--ink);
  cursor: pointer;
  list-style: none;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "";
  position: absolute;
  top: 50%; right: 24px;
  width: 9px; height: 9px;
  border-right: 2px solid var(--ink-3);
  border-bottom: 2px solid var(--ink-3);
  transform: translateY(-70%) rotate(45deg);
  transition: transform .22s;
}
.faq-item[open] { border-color: rgba(37, 211, 102, .4); }
.faq-item[open] summary { color: var(--green-dark); }
.faq-item[open] summary::after {
  transform: translateY(-30%) rotate(-135deg);
}
.faq-item .faq-body {
  padding: 0 22px 20px;
  color: var(--ink-2);
  font-size: .95rem;
}
.faq-item .faq-body p:last-child { margin-bottom: 0; }

/* ---------- 面包屑 ---------- */
.crumbs {
  padding: 14px 0;
  font-size: .84rem;
  color: var(--ink-3);
  background: var(--white);
  border-bottom: 1px solid var(--line-soft);
}
.crumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.crumbs li { margin: 0; }
.crumbs a { color: var(--ink-3); }
.crumbs a:hover { color: var(--green-dark); }
.crumbs li + li::before {
  content: "/";
  margin-right: 6px;
  color: #b6c0c6;
}
.crumbs [aria-current="page"] { color: var(--ink-2); font-weight: 600; }

/* ---------- 页头 ---------- */
.page-head {
  padding: 52px 0 46px;
  background:
    radial-gradient(circle at 88% 0%, rgba(37, 211, 102, .16), transparent 42%),
    linear-gradient(150deg, #075e54, #054640);
  color: #fff;
}
.page-head h1 { color: #fff; max-width: 820px; }
.page-head .lead {
  max-width: 720px;
  margin-bottom: 0;
  color: rgba(255, 255, 255, .8);
  font-size: 1.02rem;
}

/* ---------- CTA 条 ---------- */
.cta-band {
  position: relative;
  overflow: hidden;
  padding: 52px 0;
  background: linear-gradient(120deg, #054640, #075e54 60%, #0a6a5c);
  color: #fff;
}
.cta-band h2 { color: #fff; margin-bottom: .4em; }
.cta-band p { color: rgba(255, 255, 255, .78); margin-bottom: 0; max-width: 620px; }
.cta-band .cta-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 34px;
  flex-wrap: wrap;
}

/* ---------- 内链块 ---------- */
.link-cards { display: grid; gap: 14px; grid-template-columns: repeat(3, 1fr); }
.link-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 18px 20px;
  background: #fff;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-md);
  color: var(--ink);
  box-shadow: var(--shadow-sm);
  transition: border-color .2s, transform .2s;
}
.link-card:hover {
  border-color: var(--green);
  transform: translateY(-2px);
  text-decoration: none;
  color: var(--ink);
}
.link-card b { display: block; font-size: .96rem; }
.link-card span { font-size: .82rem; color: var(--ink-3); }
.link-card svg { width: 18px; height: 18px; color: var(--green-dark); flex: 0 0 auto; }

/* ---------- 页脚 ---------- */
.site-footer {
  padding: 56px 0 0;
  background: #04211e;
  color: rgba(255, 255, 255, .66);
  font-size: .9rem;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 36px;
  padding-bottom: 44px;
}
.site-footer h2 {
  margin-bottom: 1em;
  font-size: .82rem;
  letter-spacing: .9px;
  text-transform: uppercase;
  color: #fff;
}
.site-footer ul { margin: 0; padding: 0; list-style: none; }
.site-footer li { margin-bottom: 8px; }
.site-footer a { color: rgba(255, 255, 255, .66); }
.site-footer a:hover { color: var(--green); text-decoration: none; }
.site-footer .brand { color: #fff; margin-bottom: 14px; }
.site-footer .brand small { color: rgba(255, 255, 255, .5); }
.footer-note { font-size: .86rem; line-height: 1.7; }
.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  padding: 20px 0;
  border-top: 1px solid rgba(255, 255, 255, .1);
  font-size: .82rem;
  color: rgba(255, 255, 255, .45);
}
.footer-bottom p { margin: 0; }

/* ---------- 返回顶部 ---------- */
.to-top {
  position: fixed;
  right: 22px; bottom: 26px;
  z-index: 50;
  display: grid;
  place-items: center;
  width: 44px; height: 44px;
  border: 0;
  border-radius: 50%;
  background: var(--teal);
  color: #fff;
  box-shadow: 0 8px 24px rgba(4, 43, 38, .3);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity .25s, transform .25s, visibility .25s, background .2s;
}
.to-top.is-on { opacity: 1; visibility: visible; transform: none; }
.to-top:hover { background: var(--green-dark); }
.to-top svg { width: 20px; height: 20px; }

/* ---------- 代码/复制框 ---------- */
code {
  padding: 2px 6px;
  border-radius: 5px;
  background: #eef2f4;
  color: var(--teal);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: .9em;
  word-break: break-word;
}
.copy-box {
  margin: 22px 0;
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  background: #f8fafb;
  overflow-x: auto;
}
.copy-box pre { margin: 0; padding: 18px 20px; }
.copy-box code {
  padding: 0;
  background: none;
  color: #24333a;
  font-size: .87rem;
  line-height: 1.9;
  white-space: pre;
}

/* ---------- 响应式 ---------- */
@media (max-width: 1000px) {
  .hero-grid { grid-template-columns: 1fr; gap: 42px; }
  .layout-aside { grid-template-columns: 1fr; }
  .aside-card { position: static; }
  .grid--4 { grid-template-columns: repeat(2, 1fr); }
  .link-cards { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 820px) {
  .nav-toggle { display: grid; place-items: center; }
  .nav-list {
    position: absolute;
    top: 68px; left: 0; right: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 12px 16px 18px;
    background: var(--teal);
    border-top: 1px solid rgba(255, 255, 255, .1);
    box-shadow: 0 18px 30px rgba(4, 43, 38, .32);
  }
  .nav-list.is-open { display: flex; }
  .nav-list a { padding: 11px 14px; border-radius: 8px; }
  .nav-cta { margin: 6px 0 0; text-align: center; }
  .section { padding: 48px 0; }
  .page-head { padding: 38px 0 34px; }
  .article { padding: 30px 22px; }
  .grid--2, .grid--3, .grid--4 { grid-template-columns: 1fr; }
  .link-cards { grid-template-columns: 1fr; }
  .steps > li { padding: 20px 20px 20px 66px; }
}

@media (max-width: 560px) {
  body { font-size: 15.5px; }
  .hero { padding: 52px 0 62px; }
  .btn { width: 100%; }
  .btn-row { flex-direction: column; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
  th, td { padding: 11px 12px; }
  .article { padding: 24px 18px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .01ms !important;
    transition-duration: .01ms !important;
  }
}