:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-soft: #eff6ff;
  --text: #1f2937;
  --muted: #6b7280;
  --bg: #ffffff;
  --bg-soft: #f8fafc;
  --border: #e5e7eb;
  --radius: 14px;
  --shadow: 0 6px 24px rgba(15, 23, 42, .08);
  --maxw: 1080px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

/* 图片尺寸一律以 CSS 为准。
   HTML 上的 width/height 属性只用来“预留布局空间、防止加载抖动”（CLS），
   一旦 CSS 只写了 width 而没写 height，浏览器就会拿 height 属性当真实高度，
   图片会被硬生生拉长。这条兜底规则保证任何图片都按原比例显示。
   （需要固定高度的组件——如 .service-illu / .tier-img——用自己的类名覆盖即可） */
img { height: auto; max-width: 100%; }

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 18px; }

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ---------- Header / Nav ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,.92);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--border);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 60px; }
.brand { font-weight: 800; font-size: 18px; color: var(--text); }
.brand span { color: var(--primary); }
.nav-links { display: flex; align-items: center; gap: 18px; }
.nav-links a { color: var(--text); font-size: 15px; }
.nav-links a:hover { color: var(--primary); text-decoration: none; }
.nav-toggle {
  display: none; background: none; border: none; font-size: 22px; cursor: pointer; color: var(--text);
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-block; padding: 12px 22px; border-radius: 999px;
  font-weight: 600; font-size: 15px; cursor: pointer; transition: .15s; border: 1px solid transparent;
}
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-ghost { background: transparent; color: var(--primary); border-color: var(--primary); }
.btn-ghost:hover { background: var(--primary-soft); }
.btn-sm { padding: 8px 16px; font-size: 14px; }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  background-image: linear-gradient(95deg, rgba(255,255,255,.96) 0%, rgba(255,255,255,.80) 38%, rgba(255,255,255,.28) 70%, rgba(255,255,255,0) 100%), url('../images/hero-bg.webp');
  background-size: cover;
  background-position: center right;
  background-repeat: no-repeat;
  padding: 76px 0 60px;
}
.hero h1 { font-size: clamp(26px, 6vw, 42px); line-height: 1.25; margin-bottom: 14px; }
.lead { font-size: clamp(16px, 2.6vw, 19px); color: var(--text); max-width: 600px; font-weight: 500; }
.hero-cta { display: flex; gap: 12px; margin-top: 22px; flex-wrap: wrap; }
.hero-note { margin-top: 18px; font-size: 14px; color: var(--muted); }

/* ---------- Sections ---------- */
section { padding: 46px 0; }
.pain { background: var(--bg-soft); }
h2 { font-size: clamp(22px, 4vw, 30px); margin-bottom: 24px; text-align: center; }

.cards { display: grid; grid-template-columns: 1fr; gap: 16px; }
.card {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 22px; box-shadow: var(--shadow);
}
.card h3 { font-size: 18px; margin-bottom: 8px; color: var(--primary-dark); }
.card p { color: var(--muted); font-size: 15px; }

/* ---------- Steps ---------- */
.step-list { list-style: none; display: grid; gap: 14px; max-width: 720px; margin: 0 auto; }
.step-list li {
  display: flex; align-items: center; gap: 14px;
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius); padding: 16px 18px;
}
.step-list span {
  flex: 0 0 34px; height: 34px; border-radius: 50%; background: var(--primary); color: #fff;
  display: grid; place-items: center; font-weight: 700;
}

/* ---------- CTA final ---------- */
.cta-final { background: var(--primary-soft); text-align: center; }
.cta-final p { color: var(--muted); margin: 10px 0 20px; }

/* ---------- Footer ---------- */
.site-footer { background: #0f172a; color: #cbd5e1; padding: 36px 0 28px; }
.footer-grid { display: grid; grid-template-columns: 1fr; gap: 18px; }
.footer-grid a { color: #93c5fd; }
.brand-footer { font-weight: 800; color: #fff; font-size: 17px; margin-bottom: 6px; }
.site-footer p { font-size: 14px; margin: 4px 0; }

/* ---------- Desktop ---------- */
@media (min-width: 768px) {
  .cards { grid-template-columns: repeat(3, 1fr); }
  .footer-grid { grid-template-columns: repeat(3, 1fr); }
}

/* ---------- Mobile nav ---------- */
@media (max-width: 640px) {
  .nav-toggle { display: block; }
  .nav-links {
    position: absolute; top: 60px; left: 0; right: 0; background: #fff;
    flex-direction: column; align-items: stretch; gap: 0; border-bottom: 1px solid var(--border);
    max-height: 0; overflow: hidden; transition: max-height .2s ease;
  }
  .nav-links.open { max-height: 320px; }
  .nav-links a { padding: 14px 18px; border-top: 1px solid var(--border); }
}

/* ---------- 图片与质感增强 ---------- */
.card { transition: transform .18s ease, box-shadow .18s ease; }
.card:hover { transform: translateY(-4px); box-shadow: 0 14px 36px rgba(15,23,42,.13); }

.service-illu {
  width: 100%; height: 168px; object-fit: cover; object-position: center;
  border-radius: 12px; margin-bottom: 14px; background: var(--primary-soft);
}

/* ---------- 服务页：以服务为主角 ---------- */
.service-intro {
  text-align: center; max-width: 680px; margin: 0 auto 26px;
  color: var(--text); font-size: 16px; font-weight: 500; line-height: 1.65;
}
.service-card { display: flex; flex-direction: column; }
.svc-head { display: flex; align-items: flex-start; gap: 14px; margin-bottom: 12px; }
.svc-num {
  flex: 0 0 38px; height: 38px; border-radius: 10px;
  background: var(--primary); color: #fff;
  display: grid; place-items: center; font-weight: 800; font-size: 18px;
}
.svc-name { font-size: 20px; margin: 0 0 4px; color: var(--primary-dark); }
.svc-tagline { font-size: 14.5px; color: var(--text); font-weight: 600; margin: 0; line-height: 1.5; }
.svc-pain {
  font-size: 14px; color: var(--muted); background: var(--primary-soft);
  border-radius: 10px; padding: 10px 14px; margin: 0 0 16px; line-height: 1.55;
}
.svc-pain span {
  display: inline-block; font-size: 12px; color: #fff; background: var(--primary);
  border-radius: 6px; padding: 2px 8px; margin-right: 8px; vertical-align: middle;
}
.svc-sub { font-size: 13px; font-weight: 700; color: var(--primary-dark); margin: 0 0 8px; letter-spacing: .5px; }
.deliver { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; }
.deliver li {
  position: relative; padding-left: 24px; font-size: 14.5px; color: var(--text); line-height: 1.5;
}
.deliver li::before {
  content: "✓"; position: absolute; left: 0; top: 0; color: var(--primary); font-weight: 800;
}
.deliver-grid { grid-template-columns: 1fr; }
@media (min-width: 640px) { .deliver-grid { grid-template-columns: 1fr 1fr; } }

/* 服务页：三档大图卡片 */
.service-tier-grid {
  display: grid; gap: 20px; grid-template-columns: 1fr;
}
@media (min-width: 768px) {
  .service-tier-grid { grid-template-columns: repeat(3, 1fr); }
}
.tier-card { overflow: hidden; padding: 0; }
.tier-img {
  width: 100%; height: 180px; object-fit: cover; object-position: center;
  display: block; background: var(--primary-soft);
}
.tier-body { padding: 18px 18px 20px; }
.tier-meta { margin-bottom: 8px; }
.tier-badge {
  display: inline-block; font-size: 12px; font-weight: 700; color: #fff;
  background: var(--primary); border-radius: 999px; padding: 3px 10px;
}
.tier-name { font-size: 22px; margin: 0 0 4px; color: var(--primary-dark); }
.tier-price {
  font-size: clamp(26px, 5vw, 34px); font-weight: 900; color: #ea580c;
  line-height: 1.05; margin: 2px 0 6px; letter-spacing: .5px;
}
.tier-price-note {
  font-size: 13px; color: var(--muted); margin: 0 0 12px; font-weight: 600;
}
.tier-tagline {
  font-size: 15px; font-weight: 600; color: var(--text); margin: 0 0 14px; line-height: 1.5;
}
.tier-deliver { list-style: none; margin: 0; padding: 0; display: grid; gap: 7px; }
.tier-deliver li {
  position: relative; padding-left: 20px; font-size: 14px; color: var(--muted); line-height: 1.45;
}
.tier-deliver li::before {
  content: "✓"; position: absolute; left: 0; top: 0; color: var(--primary); font-weight: 800; font-size: 13px;
}

/* 服务页：折叠详情 + 承诺对比 */
.service-details {
  margin-top: 28px; border: 1px solid var(--border); border-radius: var(--radius);
  background: #fff; padding: 16px 18px;
}
.service-details summary {
  font-weight: 700; color: var(--primary-dark); cursor: pointer; font-size: 16px;
}
.service-details .deliver { margin-top: 14px; }
.promise-grid {
  display: grid; gap: 16px; grid-template-columns: 1fr;
}
@media (min-width: 640px) {
  .promise-grid { grid-template-columns: 1fr 1fr; }
}
.promise-card {
  border-radius: var(--radius); padding: 18px;
}
.promise-yes { background: #e8f5e9; border-left: 4px solid #2e7d32; }
.promise-no { background: #fff3e0; border-left: 4px solid #ef6c00; }
.promise-card h4 { margin: 0 0 8px; font-size: 15px; }
.promise-yes h4 { color: #2e7d32; }
.promise-no h4 { color: #c65a00; }
.promise-card p { margin: 0; font-size: 14px; line-height: 1.55; color: var(--text); }
.case-photo, .about-photo {
  width: 100%; height: auto; border-radius: var(--radius); box-shadow: var(--shadow); display: block;
}
.about-photo { max-width: 460px; margin: 0 auto; }
.photo-wrap { text-align: center; margin-bottom: 26px; }
.photo-cap { font-size: 13px; color: var(--muted); margin-top: 8px; }

.section-head { position: relative; padding-bottom: 6px; }
.section-head::after {
  content: ""; display: block; width: 48px; height: 4px; border-radius: 4px;
  background: var(--primary); margin: 12px auto 0;
}
h2 { font-size: clamp(22px, 4vw, 30px); margin-bottom: 24px; text-align: center; }
h2.section-head { margin-bottom: 28px; }

@media (min-width: 768px) {
  .about-split { display: grid; grid-template-columns: 0.9fr 1.1fr; gap: 30px; align-items: center; }
}

/* ---------- GEO 原理页 ---------- */
.geo-banner { width: 100%; max-width: 840px; height: auto; border-radius: var(--radius); box-shadow: var(--shadow); display: block; margin: 0 auto 26px; }
.geo-diagram { width: 100%; max-width: 760px; height: auto; display: block; margin: 0 auto; }
.geo-stages { display: grid; gap: 18px; max-width: 860px; margin: 18px auto 0; }
.geo-stage { display: grid; grid-template-columns: 1fr; gap: 10px; align-items: start; }
.geo-stage-icon { width: 80px; height: 80px; }
.geo-stage-body h3 { color: var(--primary-dark); margin-bottom: 4px; }
.geo-tag { display: inline-block; background: var(--primary); color: #fff; font-size: 13px; font-weight: 700; padding: 3px 12px; border-radius: 999px; margin-bottom: 6px; }
.geo-stage p { color: var(--text); font-size: 15px; margin-top: 6px; }
.geo-pain strong { color: var(--muted); }
.geo-value strong { color: #16a34a; }
@media (min-width: 768px) {
  .geo-stage { grid-template-columns: 96px 1fr; column-gap: 22px; }
  .geo-stage-icon { width: 96px; height: 96px; }
}

/* ---------- 案例页：大图 + 行业 + 种子优惠 ---------- */
.case-sample { background: var(--bg-soft); }
.case-sample-card { max-width: 860px; margin: 0 auto; text-align: center; }
.case-hero-img {
  width: 100%; max-width: 760px; height: auto; display: block;
  margin: 18px auto 22px; border-radius: var(--radius); box-shadow: var(--shadow);
}
.case-sample-card > p { color: var(--text); font-size: 16px; text-align: left; max-width: 680px; margin: 0 auto; }
.case-result-title { margin: 24px auto 10px; color: var(--primary-dark); font-size: 17px; text-align: left; max-width: 680px; }
.case-results { list-style: none; margin: 0 auto; max-width: 680px; padding: 0; display: grid; gap: 8px; text-align: left; }
.case-results li {
  position: relative; padding-left: 26px; color: var(--text); font-size: 15px; line-height: 1.5;
}
.case-results li::before {
  content: "✓"; position: absolute; left: 0; top: 0; color: #16a34a; font-weight: 800;
}

/* 行业网格 */
.case-industries { background: #fff; }
.case-ind-sub { text-align: center; color: var(--muted); max-width: 640px; margin: -8px auto 18px; font-size: 15px; }
.industry-banner {
  width: 100%; max-width: 900px; height: auto; display: block;
  margin: 0 auto 26px; border-radius: var(--radius); box-shadow: var(--shadow);
}
.industry-grid { display: grid; gap: 16px; grid-template-columns: 1fr; max-width: 920px; margin: 0 auto; }
@media (min-width: 768px) { .industry-grid { grid-template-columns: repeat(3, 1fr); } }
.industry-card { text-align: center; padding: 22px 18px; }
.industry-top { margin-bottom: 10px; }
.industry-level {
  display: inline-block; font-size: 13px; font-weight: 700; color: #fff;
  background: var(--primary); border-radius: 999px; padding: 3px 12px;
}
.industry-card:nth-child(2) .industry-level { background: #1d4ed8; }
.industry-card:nth-child(3) .industry-level { background: #64748b; }
.industry-icon { font-size: 40px; line-height: 1; margin-bottom: 8px; }
.industry-card h3 { font-size: 16px; margin-bottom: 8px; color: var(--primary-dark); }
.industry-list { color: var(--text); font-size: 14.5px; font-weight: 600; margin: 0; line-height: 1.6; }

/* 相关页面互链（每页底部「继续了解」） */
.related { background: var(--bg-soft); padding: 44px 0; border-top: 1px solid var(--border); }
.rel-grid { display: grid; gap: 14px; grid-template-columns: repeat(3, 1fr); max-width: 920px; margin: 0 auto; }
.rel-card {
  display: flex; align-items: center; justify-content: space-between;
  background: #fff; border: 1px solid var(--border); border-radius: 14px;
  padding: 18px 20px; text-decoration: none; color: var(--text);
  font-weight: 600; font-size: 16px; transition: .18s;
}
.rel-card:hover { border-color: var(--primary); box-shadow: 0 8px 20px rgba(37,99,235,.12); transform: translateY(-2px); color: var(--primary); }
.rel-arrow { color: var(--primary); font-weight: 800; }
@media (max-width: 640px) { .rel-grid { grid-template-columns: 1fr; } }

.btn-lg { padding: 14px 30px; font-size: 16px; }

/* ---------- 图说质感增强 + 首页新增区块 ---------- */
.geo-diagram { filter: drop-shadow(0 10px 22px rgba(15,23,42,.12)); }
.geo-banner { filter: drop-shadow(0 10px 26px rgba(15,23,42,.14)); }

.diagram-cap { max-width: 760px; margin: 18px auto 0; color: var(--muted); text-align: center; font-size: 15px; line-height: 1.7; }

.geo-concept { background: var(--bg-soft); }
.concept-lead { max-width: 760px; margin: 0 auto 22px; color: var(--text); text-align: center; font-size: 17px; font-weight: 500; }
.concept-img {
  display: block; width: 100%; max-width: 560px; height: auto;
  margin: 0 auto; border-radius: var(--radius); box-shadow: var(--shadow);
}
.value-compare { background: var(--bg-soft); }

@media (min-width: 768px) {
  .concept-img { max-width: 600px; }
}

/* ---------- 首页新增区块（转化漏斗） ---------- */
.scene-card { border-left: 4px solid var(--primary); }
.proof { background: var(--bg-soft); }
.proof-inner { display: grid; gap: 16px; }
.lead-magnet { background: linear-gradient(135deg, #1d4ed8, #2563eb); color: #fff; text-align: center; }
.lead-magnet .section-head::after { background: #fff; }
.lead-magnet .concept-lead { color: #e0e7ff; }
.lead-magnet .btn-ghost { color: #fff; border-color: #fff; }
.lead-magnet .btn-ghost:hover { background: rgba(255,255,255,.18); }
.lead-magnet .btn-primary { background: #fff; color: var(--primary-dark); }
.lead-magnet .btn-primary:hover { background: #f1f5f9; }
.lead-form-sec { background: var(--bg-soft); }
.price-anchor-sec { padding: 0; }
.price-anchor {
  text-align: center; font-size: clamp(15px, 3vw, 18px); font-weight: 800;
  color: #fff; background: linear-gradient(135deg, #2563eb, #1e40af);
  border-radius: 12px; padding: 14px 18px; margin: 22px auto 0; max-width: 760px;
  box-shadow: 0 10px 26px rgba(37,99,235,.22); line-height: 1.5;
}
.form-embed { max-width: 720px; margin: 0 auto; }
.form-tip { max-width: 680px; margin: 0 auto; color: var(--muted); text-align: center; background: #fff; border: 1px dashed var(--border); border-radius: 12px; padding: 16px; }
@media (min-width: 768px) {
  .proof-inner { grid-template-columns: 1.4fr 0.6fr; align-items: center; }
}