:root {
  --blue: #2563eb;
  --blue-dark: #1d4ed8;
  --blue-soft: #eff6ff;
  --blue-line: #dbeafe;
  --text: #0f172a;
  --text-2: #475569;
  --text-3: #94a3b8;
  --bg: #ffffff;
  --bg-alt: #f8fafc;
  --line: #e2e8f0;
  --radius: 16px;
  --shadow: 0 1px 2px rgba(15, 23, 42, .04), 0 8px 24px rgba(15, 23, 42, .06);
  --shadow-hover: 0 2px 4px rgba(15, 23, 42, .05), 0 16px 40px rgba(37, 99, 235, .14);
  --header-h: 60px;
}

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

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

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

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
svg { width: 100%; height: 100%; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }

.container { width: 100%; max-width: 1080px; margin: 0 auto; padding: 0 20px; }

section[id] { scroll-margin-top: calc(var(--header-h) + 8px); }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  height: 48px; padding: 0 26px; border-radius: 999px;
  font-size: 16px; font-weight: 600; border: 1px solid transparent;
  cursor: pointer; transition: background .2s, color .2s, box-shadow .2s, transform .2s;
  -webkit-tap-highlight-color: transparent; white-space: nowrap; font-family: inherit;
}
.btn:active { transform: scale(.97); }
.btn-primary { background: var(--blue); color: #fff; box-shadow: 0 6px 18px rgba(37, 99, 235, .28); }
.btn-primary:hover { background: var(--blue-dark); }
.btn-ghost { background: #fff; color: var(--blue); border-color: var(--blue-line); }
.btn-ghost:hover { background: var(--blue-soft); }
.btn-light { background: #fff; color: var(--blue); }
.btn-light:hover { background: var(--blue-soft); }
.btn-sm { height: 36px; padding: 0 16px; font-size: 14px; }

.eyebrow { font-size: 13px; font-weight: 600; letter-spacing: .08em; color: var(--blue); }
.accent { color: var(--blue); }

/* ---------- 顶栏 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50; height: var(--header-h);
  background: rgba(255, 255, 255, .82);
  backdrop-filter: saturate(180%) blur(14px); -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent; transition: border-color .2s;
}
.site-header.scrolled { border-bottom-color: var(--line); }
.header-inner { height: 100%; display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 18px; }
.logo-mark {
  width: 32px; height: 32px; border-radius: 9px; background: var(--blue); color: #fff;
  display: grid; place-items: center; font-size: 16px;
}
.nav { display: none; gap: 32px; font-size: 15px; color: var(--text-2); }
.nav a:hover { color: var(--blue); }

/* ---------- 首屏 ---------- */
.hero {
  position: relative; overflow: hidden;
  padding: 72px 0 80px;
  background:
    radial-gradient(600px 300px at 85% 0%, rgba(37, 99, 235, .12), transparent 70%),
    radial-gradient(500px 260px at 0% 100%, rgba(96, 165, 250, .12), transparent 70%),
    linear-gradient(180deg, #f5f9ff 0%, #ffffff 100%);
}
.hero-inner { text-align: center; }
.hero-title { font-size: 38px; line-height: 1.25; font-weight: 800; margin: 14px 0 16px; letter-spacing: -.01em; }
.hero-sub { font-size: 17px; color: var(--text-2); max-width: 560px; margin: 0 auto; }
.hero-sub strong { color: var(--text); font-weight: 600; }
.hero-actions { display: flex; gap: 12px; justify-content: center; margin-top: 32px; flex-wrap: wrap; }
.hero-actions .btn { flex: 1 1 140px; max-width: 200px; }
.hero-points {
  list-style: none; display: flex; flex-wrap: wrap; justify-content: center;
  gap: 10px 22px; margin-top: 32px; font-size: 14px; color: var(--text-2);
}
.hero-points li { display: flex; align-items: center; gap: 8px; }
.dot { width: 6px; height: 6px; border-radius: 50%; background: var(--blue); }

/* ---------- 通用区块 ---------- */
.section { padding: 72px 0; }
.section-alt { background: var(--bg-alt); }
.section-head { text-align: center; margin-bottom: 36px; }
.section-head h2 { font-size: 28px; font-weight: 800; margin-top: 6px; }

.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow); transition: transform .25s, box-shadow .25s, border-color .25s;
}

/* ---------- 服务 ---------- */
.service-grid { display: grid; grid-template-columns: 1fr; gap: 14px; }
.service-card { padding: 22px 22px 22px 20px; display: grid; grid-template-columns: 48px 1fr; column-gap: 16px; align-items: start; }
.service-card h3 { font-size: 18px; font-weight: 700; margin-bottom: 4px; }
.service-card p { grid-column: 2; font-size: 15px; color: var(--text-2); }
.icon-box {
  grid-row: span 2; width: 48px; height: 48px; border-radius: 12px;
  background: var(--blue-soft); color: var(--blue); padding: 12px;
}

/* ---------- 流程 ---------- */
.steps { list-style: none; display: grid; gap: 0; max-width: 560px; margin: 0 auto; }
.step { position: relative; display: flex; gap: 18px; padding-bottom: 28px; }
.step:last-child { padding-bottom: 0; }
.step::before {
  content: ""; position: absolute; left: 21px; top: 44px; bottom: 4px;
  width: 2px; background: var(--blue-line);
}
.step:last-child::before { display: none; }
.step-num {
  flex: none; width: 44px; height: 44px; border-radius: 50%; position: relative; z-index: 1;
  background: var(--blue); color: #fff; font-weight: 700; font-size: 18px;
  display: grid; place-items: center; box-shadow: 0 0 0 6px var(--blue-soft);
}
.step h3 { font-size: 18px; font-weight: 700; margin: 8px 0 2px; }
.step p { font-size: 15px; color: var(--text-2); }

/* ---------- 作品 ---------- */
.works-grid { display: grid; grid-template-columns: 1fr; gap: 18px; }
.work-card { overflow: hidden; display: block; }
.work-shot {
  aspect-ratio: 16 / 10; width: 100%; object-fit: cover;
  background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
  display: grid; place-items: center;
}
.work-shot span { font-size: 14px; color: #93b4ea; font-weight: 600; letter-spacing: .1em; }
.work-body { padding: 16px 20px 20px; }
.work-body h3 { font-size: 17px; font-weight: 700; }
.work-body p { font-size: 14px; color: var(--text-3); margin-top: 2px; }
img.work-shot { object-position: top; border-bottom: 1px solid var(--line); }
a.work-card .work-body p { color: var(--text-2); }
.work-go { color: var(--blue); font-weight: 600; white-space: nowrap; }
a.work-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); border-color: var(--blue-line); }

/* ---------- 联系 ---------- */
.section-contact { padding-top: 24px; }
.contact-card {
  border-radius: 24px; padding: 36px 24px; color: #fff; text-align: center;
  background:
    radial-gradient(400px 200px at 100% 0%, rgba(255, 255, 255, .18), transparent 70%),
    linear-gradient(135deg, #2563eb 0%, #1e40af 100%);
  box-shadow: 0 20px 50px rgba(37, 99, 235, .3);
  display: flex; flex-direction: column; align-items: center; gap: 28px;
}
.eyebrow-light { color: rgba(255, 255, 255, .75); }
.contact-card h2 { font-size: 26px; font-weight: 800; margin: 6px 0 10px; line-height: 1.35; }
.contact-sub { font-size: 15px; color: rgba(255, 255, 255, .85); max-width: 420px; margin: 0 auto; }
.wechat-row {
  display: inline-flex; align-items: center; gap: 10px; flex-wrap: wrap; justify-content: center;
  margin-top: 22px; padding: 8px 8px 8px 18px; border-radius: 999px;
  background: rgba(255, 255, 255, .14); border: 1px solid rgba(255, 255, 255, .22);
}
.wechat-label { font-size: 13px; color: rgba(255, 255, 255, .75); }
.wechat-id { font-size: 18px; font-weight: 700; letter-spacing: .02em; word-break: break-all; }

.qr-box { display: flex; flex-direction: column; align-items: center; }
.qr-box img, .qr-placeholder {
  width: 180px; height: 180px; border-radius: 16px; background: #fff; padding: 10px;
}
.qr-box img { display: none; object-fit: contain; }
.qr-box.has-qr img { display: block; }
.qr-box.has-qr .qr-placeholder { display: none; }
.qr-placeholder {
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 10px;
  color: var(--text-3); font-size: 14px; border: 2px dashed rgba(255, 255, 255, .5);
  background: rgba(255, 255, 255, .92);
}
.qr-placeholder svg { width: 56px; height: 56px; color: #93b4ea; }
.qr-tip { font-size: 13px; color: rgba(255, 255, 255, .75); margin-top: 10px; }

/* ---------- 页脚 ---------- */
.site-footer { padding: 36px 0; text-align: center; font-size: 13px; color: var(--text-3); }

/* ---------- 提示 ---------- */
.toast {
  position: fixed; left: 50%; bottom: 32px; z-index: 100;
  transform: translate(-50%, 20px); opacity: 0; pointer-events: none;
  background: var(--text); color: #fff; font-size: 14px;
  padding: 10px 20px; border-radius: 999px; transition: opacity .25s, transform .25s;
}
.toast.show { opacity: 1; transform: translate(-50%, 0); }

/* ---------- 进场动画 ---------- */
.js .reveal { opacity: 0; transform: translateY(18px); transition: opacity .6s ease, transform .6s ease; }
.js .reveal.visible { opacity: 1; transform: none; }

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

/* ---------- 平板及以上 ---------- */
@media (min-width: 720px) {
  .hero { padding: 110px 0 120px; }
  .hero-title { font-size: 56px; }
  .hero-sub { font-size: 19px; }
  .section { padding: 96px 0; }
  .section-head { margin-bottom: 48px; }
  .section-head h2 { font-size: 34px; }

  .service-grid { grid-template-columns: repeat(2, 1fr); gap: 20px; }
  .service-card { display: block; padding: 28px; }
  .service-card .icon-box { margin-bottom: 18px; }
  .service-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); border-color: var(--blue-line); }

  .works-grid { grid-template-columns: repeat(2, 1fr); gap: 24px; }

  .contact-card {
    flex-direction: row; justify-content: space-between; text-align: left;
    padding: 52px 56px; gap: 40px;
  }
  .contact-card h2 { font-size: 32px; }
  .contact-sub { margin: 0; }
}

@media (min-width: 900px) {
  .nav { display: flex; }
  .service-grid { grid-template-columns: repeat(4, 1fr); }

  .steps { max-width: none; grid-template-columns: repeat(4, 1fr); gap: 24px; }
  .step { flex-direction: column; gap: 14px; padding-bottom: 0; }
  .step::before { left: 56px; right: -24px; top: 21px; bottom: auto; width: auto; height: 2px; }
  .step h3 { margin-top: 4px; }
}