/* ================================================================
   易翻译 · 全站样式
   纯手写原生 CSS —— 不依赖 Tailwind / Bootstrap
   主色取自 Logo： #2563EB
   ================================================================ */

:root {
  --blue:        #2563EB;
  --blue-d:      #1D4ED8;
  --blue-l:      #60A5FA;
  --blue-50:     #EFF6FF;
  --blue-100:    #DBEAFE;
  --grad:        linear-gradient(135deg, #2563EB 0%, #4F8EF7 55%, #7DB4FF 100%);

  --ink:         #0F172A;
  --ink-2:       #334155;
  --ink-3:       #64748B;
  --ink-4:       #94A3B8;

  --bg:          #FFFFFF;
  --bg-alt:      #F6F9FF;
  --bg-dark:     #0B1B3A;
  --line:        #E3EAF6;
  --line-2:      #EDF2FA;

  --radius:      14px;
  --radius-lg:   20px;
  --radius-pill: 999px;

  --shadow-s:    0 1px 2px rgba(15,23,42,.05), 0 2px 8px rgba(37,99,235,.05);
  --shadow-m:    0 4px 12px rgba(15,23,42,.06), 0 12px 32px rgba(37,99,235,.08);
  --shadow-l:    0 12px 32px rgba(37,99,235,.14), 0 28px 64px rgba(15,23,42,.10);

  --container:   1200px;
  --gap:         24px;
  --section:     80px;

  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
          "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC",
          "Noto Sans CJK SC", Roboto, Helvetica, Arial, sans-serif;
}

/* ---------------- reset ---------------- */
* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink-2);
  background: var(--bg);
  overflow-x: hidden;
}
h1, h2, h3, h4 { color: var(--ink); line-height: 1.28; margin: 0; font-weight: 700; }
p { margin: 0; }
a { color: var(--blue); text-decoration: none; transition: color .2s; }
a:hover { color: var(--blue-d); }
img { max-width: 100%; height: auto; display: block; }
ul { margin: 0; padding: 0; list-style: none; }
button { font-family: inherit; cursor: pointer; border: 0; background: none; }
table { border-collapse: collapse; width: 100%; }

.skip-link {
  position: absolute; left: -9999px; top: 0; z-index: 999;
  background: var(--blue); color: #fff; padding: 10px 18px;
}
.skip-link:focus { left: 8px; top: 8px; }

/* ---------------- layout ---------------- */
.container {
  width: 100%; max-width: var(--container);
  margin: 0 auto; padding: 0 24px;
}
.container-narrow { max-width: 860px; }
.section { padding: var(--section) 0; }
.section-alt { background: var(--bg-alt); }

.section-head { text-align: center; max-width: 780px; margin: 0 auto 44px; }
.section-head-left { text-align: left; margin-left: 0; max-width: 100%; }
.eyebrow {
  display: inline-block; font-size: 13px; font-weight: 700; letter-spacing: .08em;
  color: var(--blue); background: var(--blue-50);
  padding: 5px 14px; border-radius: var(--radius-pill); margin-bottom: 14px;
}
.eyebrow-light { color: #CDE0FF; background: rgba(255,255,255,.12); }
.section-head h2 { font-size: 34px; margin-bottom: 12px; }
.section-sub { font-size: 16px; color: var(--ink-3); }
.section-sub a { font-weight: 600; }
.section-note {
  text-align: center; margin-top: 22px; font-size: 14px; color: var(--ink-3);
}
.section-more { text-align: center; margin-top: 40px; }
.ph { color: #C2410C; font-weight: 600; }
.ph-inline { color: #C2410C; font-weight: 600; font-style: normal; }

/* ---------------- buttons ---------------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 12px 24px; border-radius: var(--radius-pill);
  font-size: 15px; font-weight: 600; line-height: 1;
  border: 1.5px solid transparent; transition: all .22s ease;
  white-space: nowrap; text-align: center;
}
.btn i { font-size: 14px; }
.btn-primary { background: var(--grad); color: #fff; box-shadow: 0 6px 18px rgba(37,99,235,.28); }
.btn-primary:hover { color: #fff; transform: translateY(-2px); box-shadow: 0 12px 26px rgba(37,99,235,.34); }
.btn-outline { border-color: var(--line); background: #fff; color: var(--ink); }
.btn-outline:hover { border-color: var(--blue); color: var(--blue); transform: translateY(-2px); }
.btn-light { background: #fff; color: var(--blue-d); }
.btn-light:hover { color: var(--blue-d); transform: translateY(-2px); box-shadow: 0 10px 26px rgba(0,0,0,.18); }
.btn-ghost-light { border-color: rgba(255,255,255,.5); color: #fff; }
.btn-ghost-light:hover { background: rgba(255,255,255,.14); color: #fff; }
.btn-sm { padding: 9px 18px; font-size: 14px; }
.btn-lg { padding: 15px 30px; font-size: 16px; }
.btn-block { width: 100%; }

/* ---------------- notice bar ---------------- */
.notice-bar {
  background: #FFF8ED; border-bottom: 1px solid #FDE7C4;
  font-size: 13.5px; color: #8A5A12;
}
.notice-inner { display: flex; align-items: center; gap: 12px; padding: 9px 24px; }
.notice-inner p { flex: 1; margin: 0; line-height: 1.6; }
.notice-inner strong { color: #C2410C; }
.notice-inner a { color: #C2410C; text-decoration: underline; white-space: nowrap; }
.notice-dot {
  width: 8px; height: 8px; border-radius: 50%; background: #F59E0B; flex: 0 0 auto;
  box-shadow: 0 0 0 4px rgba(245,158,11,.18);
}
.notice-close { font-size: 20px; line-height: 1; color: #B47A1E; padding: 0 4px; }
.notice-bar.hide { display: none; }

/* ---------------- header ---------------- */
.site-header {
  position: sticky; top: 0; z-index: 90;
  background: rgba(255,255,255,.92); backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line-2); transition: box-shadow .25s;
}
.site-header.scrolled { box-shadow: 0 4px 20px rgba(15,23,42,.08); }
.header-inner { display: flex; align-items: center; gap: 20px; height: 72px; }
.brand { flex: 0 0 auto; display: flex; align-items: center; }
.brand-logo { height: 40px; width: auto; }
.main-nav { flex: 1; }
.nav-list { display: flex; gap: 4px; justify-content: center; flex-wrap: wrap; }
.nav-link {
  display: block; padding: 8px 14px; border-radius: 10px;
  font-size: 15px; font-weight: 500; color: var(--ink-2);
}
.nav-link:hover { background: var(--blue-50); color: var(--blue); }
.nav-link.active { color: var(--blue); font-weight: 700; background: var(--blue-50); }
.header-actions { display: flex; align-items: center; gap: 12px; flex: 0 0 auto; }
.menu-toggle {
  display: none; width: 42px; height: 42px; border-radius: 10px;
  border: 1px solid var(--line); flex-direction: column;
  align-items: center; justify-content: center; gap: 5px;
}
.menu-toggle span {
  display: block; width: 18px; height: 2px; background: var(--ink);
  border-radius: 2px; transition: .25s;
}
.menu-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.menu-toggle.open span:nth-child(2) { opacity: 0; }
.menu-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------------- hero ---------------- */
.hero { position: relative; overflow: hidden; padding: 72px 0 80px; }
.hero-bg {
  position: absolute; inset: 0; z-index: 0;
  background: linear-gradient(120deg, #EEF5FF 0%, #F7FAFF 30%, #EAF2FF 55%, #F5F9FF 80%, #EEF5FF 100%);
  background-size: 220% 220%;
  animation: heroFlow 16s ease-in-out infinite;
}
@keyframes heroFlow {
  0%   { background-position: 0% 50%; }
  50%  { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}
.hero::before, .hero::after {
  content: ""; position: absolute; border-radius: 50%; z-index: 0;
  filter: blur(70px); opacity: .5; pointer-events: none;
}
.hero::before {
  width: 420px; height: 420px; background: rgba(96,165,250,.55);
  top: -120px; left: -80px; animation: floatA 18s ease-in-out infinite;
}
.hero::after {
  width: 360px; height: 360px; background: rgba(147,197,253,.5);
  bottom: -140px; right: -60px; animation: floatB 22s ease-in-out infinite;
}
@keyframes floatA {
  0%,100% { transform: translate(0,0) scale(1); }
  50%     { transform: translate(60px,40px) scale(1.12); }
}
@keyframes floatB {
  0%,100% { transform: translate(0,0) scale(1.05); }
  50%     { transform: translate(-70px,-40px) scale(.94); }
}
.hero-inner {
  position: relative; z-index: 1;
  display: grid; grid-template-columns: 1.06fr .94fr; gap: 56px; align-items: center;
}
.badge {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 13px; font-weight: 600; color: var(--blue-d);
  background: rgba(255,255,255,.85); border: 1px solid var(--blue-100);
  padding: 7px 16px; border-radius: var(--radius-pill); margin-bottom: 20px;
  box-shadow: var(--shadow-s);
}
.hero h1 { font-size: 44px; letter-spacing: -.5px; margin-bottom: 14px; }
.hero-sub { font-size: 18px; font-weight: 600; color: var(--blue-d); margin-bottom: 14px; }
.hero-desc { font-size: 16px; color: var(--ink-3); margin-bottom: 28px; }
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 36px; }

.stats { display: flex; gap: 34px; flex-wrap: wrap; }
.stat { display: flex; flex-direction: column; }
.stat strong { font-size: 26px; font-weight: 800; color: var(--blue-d); line-height: 1.2; }
.stat span { font-size: 13px; color: var(--ink-3); }

/* 演示框 */
.hero-visual { position: relative; }
.demo-frame {
  position: relative; overflow: hidden;
  background: #fff; border: 1px solid var(--line);
  border-radius: var(--radius-lg); box-shadow: var(--shadow-l);
}
.demo-head {
  display: flex; align-items: center; gap: 7px;
  padding: 12px 16px; border-bottom: 1px solid var(--line-2); background: #FAFCFF;
}
.demo-head .dot { width: 10px; height: 10px; border-radius: 50%; }
.dot.r { background: #FF6058; } .dot.y { background: #FFBE2E; } .dot.g { background: #28C840; }
.demo-title { margin-left: 8px; font-size: 12.5px; color: var(--ink-3); font-weight: 600; }
.demo-body { padding: 18px; display: flex; flex-direction: column; gap: 12px; }
.msg { max-width: 84%; padding: 10px 14px; border-radius: 14px; font-size: 13.5px; }
.msg .src { font-size: 13.5px; line-height: 1.6; }
.msg .dst {
  margin-top: 6px; padding-top: 6px; border-top: 1px dashed var(--line);
  font-size: 13px; line-height: 1.6; color: var(--blue-d); font-weight: 600;
}
.msg.in { background: #F2F6FD; border-bottom-left-radius: 4px; align-self: flex-start; color: var(--ink-2); }
.msg.out { background: var(--blue-50); border-bottom-right-radius: 4px; align-self: flex-end; color: var(--ink-2); }
.msg.out .dst { color: #0E7490; }
.demo-scan {
  position: absolute; left: 0; right: 0; height: 90px; top: -90px;
  background: linear-gradient(180deg, rgba(96,165,250,0), rgba(96,165,250,.22), rgba(96,165,250,0));
  animation: scan 5.5s linear infinite;
}
@keyframes scan {
  0%   { top: -90px; }
  100% { top: 100%; }
}

/* ---------------- cards & grids ---------------- */
.grid { display: grid; gap: var(--gap); }
.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 {
  background: #fff; border: 1px solid var(--line);
  border-radius: var(--radius); padding: 28px 24px;
  transition: transform .25s ease, box-shadow .25s ease, border-color .25s;
  display: block;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-m); border-color: var(--blue-100); }
.card h3 { font-size: 18px; margin-bottom: 10px; }
.card p { font-size: 14.5px; color: var(--ink-3); line-height: 1.72; }
.card-icon {
  width: 48px; height: 48px; border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  background: var(--blue-50); color: var(--blue); font-size: 20px;
  margin-bottom: 16px; transition: .25s;
}
.card:hover .card-icon { background: var(--grad); color: #fff; }

/* 优势 */
.adv-item { display: flex; gap: 16px; background: #fff; border: 1px solid var(--line);
  border-radius: var(--radius); padding: 24px; transition: .25s; }
.adv-item:hover { transform: translateY(-4px); box-shadow: var(--shadow-m); border-color: var(--blue-100); }
.adv-icon {
  flex: 0 0 44px; width: 44px; height: 44px; border-radius: 12px;
  background: var(--grad); color: #fff; font-size: 18px;
  display: flex; align-items: center; justify-content: center;
}
.adv-item h3 { font-size: 17px; margin-bottom: 8px; }
.adv-item p { font-size: 14.5px; color: var(--ink-3); }

/* 场景卡 */
.scene-card { display: flex; flex-direction: column; }
.scene-more { margin-top: auto; padding-top: 16px; font-size: 14px; font-weight: 600; color: var(--blue); }
.scene-card:hover .scene-more { color: var(--blue-d); }

/* 步骤 */
.steps { counter-reset: step; }
.step { position: relative; background: #fff; border: 1px solid var(--line);
  border-radius: var(--radius); padding: 30px 24px 26px; transition: .25s; }
.step:hover { transform: translateY(-4px); box-shadow: var(--shadow-m); border-color: var(--blue-100); }
.step-no {
  position: absolute; top: -14px; left: 24px;
  font-size: 13px; font-weight: 800; color: #fff; letter-spacing: .06em;
  background: var(--grad); padding: 4px 12px; border-radius: var(--radius-pill);
  box-shadow: 0 4px 12px rgba(37,99,235,.3);
}
.step-icon { width: 44px; height: 44px; border-radius: 12px; background: var(--blue-50);
  color: var(--blue); display: flex; align-items: center; justify-content: center;
  font-size: 18px; margin: 8px 0 14px; }
.step h3 { font-size: 17px; margin-bottom: 8px; }
.step p { font-size: 14.5px; color: var(--ink-3); }

/* 平台卡 */
.platform-card { text-align: center; display: flex; flex-direction: column; }
.platform-card .card-icon { margin: 0 auto 16px; }
.plat-req { font-size: 13.5px; color: var(--ink-3); min-height: 42px; }
.plat-size { font-size: 13px; color: var(--ink-4); margin: 8px 0 18px; }
.platform-card .btn { margin-top: auto; }

/* ---------------- FAQ ---------------- */
.faq-list { display: flex; flex-direction: column; gap: 12px; }
.faq-item { background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden; transition: border-color .25s, box-shadow .25s; }
.faq-item.open { border-color: var(--blue-100); box-shadow: var(--shadow-s); }
.faq-q {
  width: 100%; display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 18px 22px; text-align: left; font-size: 16px; font-weight: 600; color: var(--ink);
}
.faq-q i { color: var(--blue); font-size: 13px; transition: transform .28s; flex: 0 0 auto; }
.faq-item.open .faq-q i { transform: rotate(180deg); }
.faq-a { max-height: 0; overflow: hidden; transition: max-height .32s ease; }
.faq-a p { padding: 0 22px 20px; font-size: 14.5px; color: var(--ink-3); line-height: 1.8; }

/* ---------------- 关键词云（深色） ---------------- */
.kw-cloud-section { background: var(--bg-dark); position: relative; overflow: hidden; }
.kw-cloud-section::before {
  content: ""; position: absolute; width: 520px; height: 520px; border-radius: 50%;
  background: radial-gradient(circle, rgba(37,99,235,.55), transparent 70%);
  top: -220px; right: -120px;
}
.kw-cloud-section .section-head h2 { color: #fff; }
.kw-cloud-section .section-head .section-sub { color: #A9BEDD; }
.kw-cloud-section .section-sub a { color: #8FC0FF; }
.kw-cloud { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; position: relative; }
.kw-tag {
  display: inline-flex; align-items: center; gap: 7px;
  padding: 8px 16px; border-radius: var(--radius-pill);
  background: rgba(255,255,255,.07); border: 1px solid rgba(255,255,255,.14);
  color: #D7E5FA; font-size: 14px; transition: .22s;
}
.kw-tag:hover {
  background: rgba(96,165,250,.2); border-color: rgba(147,197,253,.5);
  color: #fff; transform: translateY(-2px);
}
.kw-tag em { font-style: normal; font-size: 10.5px; color: #FBBF24; letter-spacing: -.5px; }

/* ---------------- CTA band ---------------- */
.cta-band { background: var(--grad); background-size: 200% 200%; animation: heroFlow 22s ease-in-out infinite; padding: 64px 0; }
.cta-inner { display: flex; align-items: center; justify-content: space-between; gap: 32px; flex-wrap: wrap; }
.cta-inner h2 { color: #fff; font-size: 30px; margin-bottom: 10px; }
.cta-inner p { color: #DCEAFF; font-size: 15.5px; max-width: 620px; }
.cta-actions { display: flex; gap: 14px; flex-wrap: wrap; }

/* ---------------- footer ---------------- */
.site-footer { background: #071431; color: #93A9C9; padding: 60px 0 26px; font-size: 14px; }
.footer-top { display: grid; grid-template-columns: 320px 1fr; gap: 48px; padding-bottom: 42px; border-bottom: 1px solid rgba(255,255,255,.08); }
.footer-logo { height: 40px; width: auto; margin-bottom: 18px; filter: brightness(0) invert(1); opacity: .92; }
.footer-desc { font-size: 13.5px; line-height: 1.85; color: #8399B8; margin-bottom: 18px; }
.footer-contact p { font-size: 13px; margin-bottom: 7px; color: #8399B8; }
.footer-contact i { color: var(--blue-l); width: 16px; }
.footer-cols { display: grid; grid-template-columns: repeat(4, 1fr); gap: 28px; }
.footer-col h3 { color: #fff; font-size: 14.5px; margin-bottom: 14px; }
.footer-col ul { display: flex; flex-direction: column; gap: 8px; }
.footer-col a { color: #8FA6C4; font-size: 13px; }
.footer-col a:hover { color: #fff; }
.footer-bottom { padding-top: 22px; }
.footer-legal { font-size: 12.5px; line-height: 1.8; color: #6F88AB; margin-bottom: 16px; }
.footer-legal strong { color: #A9BEDD; }
.footer-meta { display: flex; gap: 22px; flex-wrap: wrap; font-size: 12.5px; color: #6F88AB; }
.footer-meta .ph, .footer-legal .ph { color: #FBBF24; }

/* ---------------- 关键词大全页 ---------------- */
.kw-groups { display: flex; flex-direction: column; gap: 40px; }
.kw-group h2 { font-size: 22px; margin-bottom: 18px; display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.kw-count { font-size: 12.5px; font-weight: 600; color: var(--blue); background: var(--blue-50);
  padding: 3px 12px; border-radius: var(--radius-pill); }
.kw-list { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; }
.kw-row {
  display: flex; align-items: center; justify-content: space-between; gap: 10px;
  padding: 11px 16px; background: #fff; border: 1px solid var(--line);
  border-radius: 10px; transition: .2s;
}
.kw-row:hover { border-color: var(--blue); transform: translateY(-2px); box-shadow: var(--shadow-s); }
.kw-row a { font-size: 14.5px; font-weight: 600; color: var(--ink); }
.kw-row:hover a { color: var(--blue); }
.kw-row-main { background: var(--blue-50); border-color: var(--blue-100); }
.kw-row-main a { color: var(--blue-d); }
.kw-heat { font-size: 11px; color: #F59E0B; letter-spacing: -.5px; flex: 0 0 auto; }

/* ---------------- 对比表 ---------------- */
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; }
.cmp-table { min-width: 620px; font-size: 14.5px; }
.cmp-table th, .cmp-table td { padding: 15px 20px; text-align: left; border-bottom: 1px solid var(--line-2); }
.cmp-table thead th { background: var(--blue-50); color: var(--blue-d); font-weight: 700; font-size: 14px; }
.cmp-table tbody tr:last-child td { border-bottom: 0; }
.cmp-table tbody tr:hover { background: #FAFCFF; }
.cmp-table td:first-child { font-weight: 600; color: var(--ink); }

/* ---------------- 博客 ---------------- */
.blog-card { display: flex; flex-direction: column; }
.blog-meta { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; font-size: 12.5px; }
.blog-cat {
  display: inline-block; font-size: 12px; font-weight: 700; color: var(--blue-d);
  background: var(--blue-50); padding: 3px 11px; border-radius: var(--radius-pill);
}
.blog-meta time { color: var(--ink-4); }
.blog-card h3 { font-size: 17px; line-height: 1.45; margin-bottom: 10px; }
.blog-card p { font-size: 14px; color: var(--ink-3); }
.blog-more { margin-top: auto; padding-top: 16px; font-size: 13.5px; font-weight: 600; color: var(--blue); }

/* 文章页 */
.page-article { background: #fff; }
.article-head { padding: 42px 0 30px; background: var(--bg-alt); border-bottom: 1px solid var(--line); }
.breadcrumb { display: flex; align-items: center; gap: 9px; font-size: 13px; color: var(--ink-4); margin-bottom: 18px; flex-wrap: wrap; }
.breadcrumb a { color: var(--ink-3); }
.breadcrumb a:hover { color: var(--blue); }
.breadcrumb i { font-size: 10px; }
.article-head h1 { font-size: 34px; line-height: 1.36; margin: 12px 0 14px; }
.article-meta { font-size: 13.5px; color: var(--ink-4); margin-bottom: 16px; }
.article-lead { font-size: 16.5px; color: var(--ink-2); line-height: 1.8;
  padding-left: 16px; border-left: 3px solid var(--blue); }
.article-body { padding: 40px 0 24px; }
.article-body p { font-size: 16.5px; line-height: 1.95; color: var(--ink-2); margin-bottom: 22px; }
.article-foot { padding: 32px 0 60px; }
.article-note { font-size: 13px; line-height: 1.8; color: var(--ink-3);
  background: #FFF8ED; border: 1px solid #FDE7C4; border-radius: 12px; padding: 16px 20px; margin-bottom: 28px; }
.article-note strong { color: #C2410C; }
.article-rel h3 { font-size: 16px; margin-bottom: 14px; }
.article-rel ul { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; margin-bottom: 28px; }
.article-rel li a {
  display: block; padding: 12px 16px; background: var(--bg-alt);
  border: 1px solid var(--line); border-radius: 10px; font-size: 14px; color: var(--ink-2);
}
.article-rel li a:hover { border-color: var(--blue); color: var(--blue); background: #fff; }
.article-pn { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.pn-prev, .pn-next { display: flex; flex-direction: column; gap: 5px;
  padding: 16px 20px; border: 1px solid var(--line); border-radius: 12px; background: #fff; }
.pn-prev:hover, .pn-next:hover { border-color: var(--blue); }
.pn-prev span, .pn-next span { font-size: 12.5px; color: var(--ink-4); }
.pn-prev strong, .pn-next strong { font-size: 14.5px; color: var(--ink); font-weight: 600; }
.pn-next { text-align: right; }

/* ---------------- 免责声明 / 404 ---------------- */
.disc-list { display: flex; flex-direction: column; gap: 22px; }
.disc-item { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 24px 26px; }
.disc-item h2 { font-size: 18px; margin-bottom: 10px; color: var(--blue-d); }
.disc-item p { font-size: 15px; color: var(--ink-2); line-height: 1.85; }
.err-wrap { text-align: center; padding: 60px 0 80px; }
.err-wrap h1 { font-size: 40px; margin-bottom: 12px; }
.err-links { display: flex; gap: 12px; flex-wrap: wrap; justify-content: center; margin: 26px 0; }
.err-links a { padding: 9px 18px; border: 1px solid var(--line); border-radius: var(--radius-pill);
  font-size: 14px; font-weight: 600; color: var(--ink-2); }
.err-links a:hover { border-color: var(--blue); color: var(--blue); }

/* ---------------- to-top ---------------- */
.to-top {
  position: fixed; right: 24px; bottom: 28px; z-index: 80;
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--grad); color: #fff; box-shadow: var(--shadow-m);
  display: flex; align-items: center; justify-content: center; font-size: 15px;
  opacity: 0; visibility: hidden; transform: translateY(12px); transition: .28s;
}
.to-top.show { opacity: 1; visibility: visible; transform: translateY(0); }

/* ---------------- 进场动画 ---------------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ================================================================
   响应式：1200 / 992 / 768 / 480 四档
   ================================================================ */
@media (max-width: 1200px) {
  .footer-cols { grid-template-columns: repeat(2, 1fr); }
  .footer-top { grid-template-columns: 280px 1fr; gap: 36px; }
}
@media (max-width: 992px) {
  :root { --section: 64px; }
  .hero { padding: 52px 0 62px; }
  .hero-inner { grid-template-columns: 1fr; gap: 40px; }
  .hero h1 { font-size: 36px; }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .kw-list { grid-template-columns: repeat(2, 1fr); }
  .footer-top { grid-template-columns: 1fr; gap: 34px; }
  .footer-cols { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  :root { --section: 56px; --gap: 18px; }
  body { font-size: 15.5px; }
  .notice-inner { font-size: 12.5px; align-items: flex-start; }
  .notice-inner p { line-height: 1.7; }

  .menu-toggle { display: flex; }
  .main-nav {
    position: absolute; left: 0; right: 0; top: 100%;
    background: #fff; border-bottom: 1px solid var(--line);
    box-shadow: 0 14px 30px rgba(15,23,42,.1);
    max-height: 0; overflow: hidden; transition: max-height .3s ease;
  }
  .main-nav.open { max-height: 460px; }
  .nav-list { flex-direction: column; gap: 0; padding: 10px 24px 20px; }
  .nav-link { padding: 13px 4px; border-radius: 0; border-bottom: 1px solid var(--line-2); }
  .header-actions .btn-sm { display: none; }

  .section-head h2 { font-size: 26px; }
  .hero h1 { font-size: 28px; }
  .hero-sub { font-size: 16px; }
  .hero-desc { font-size: 15px; }
  .hero-actions .btn { flex: 1 1 100%; }
  .stats { gap: 20px; }
  .stat strong { font-size: 22px; }

  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .kw-list { grid-template-columns: 1fr; }
  .cta-inner h2 { font-size: 23px; }
  .cta-actions { width: 100%; }
  .cta-actions .btn { flex: 1 1 100%; }

  .article-head h1 { font-size: 25px; }
  .article-body p { font-size: 16px; }
  .article-rel ul { grid-template-columns: 1fr; }
  .article-pn { grid-template-columns: 1fr; }
  .pn-next { text-align: left; }

  .footer-cols { grid-template-columns: repeat(2, 1fr); gap: 22px; }
  .footer-meta { gap: 10px; flex-direction: column; }
  .disc-item { padding: 20px; }
  .err-wrap h1 { font-size: 30px; }
}
@media (max-width: 480px) {
  :root { --section: 48px; }
  .container { padding: 0 16px; }
  .hero h1 { font-size: 24px; }
  .brand-logo { height: 34px; }
  .footer-cols { grid-template-columns: 1fr; }
  .msg { max-width: 100%; }
  .demo-body { padding: 14px; gap: 10px; }
  .card { padding: 22px 18px; }
  .step { padding: 26px 18px 22px; }
  .faq-q { padding: 15px 16px; font-size: 15px; }
  .faq-a p { padding: 0 16px 16px; }
  .to-top { right: 14px; bottom: 16px; width: 40px; height: 40px; }
}

/* ---------------- 减少动效 ---------------- */
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; }
}

/* ---------------- 打印 ---------------- */
@media print {
  .site-header, .notice-bar, .cta-band, .to-top, .menu-toggle { display: none !important; }
  body { color: #000; }
}