:root {
  --ink: #14181d;
  --ink-2: #3d4650;
  --ink-3: #6b7681;
  --line: #e2e6ea;
  --bg: #ffffff;
  --bg-2: #f6f8f9;
  --accent: #165c4a;
  --accent-soft: #eaf2ef;
  --warn: #8a5a12;
  --radius: 4px;
  --maxw: 960px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

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

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

.wrap {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- skip link (a11y) ---------- */
.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--ink);
  color: #fff;
  padding: 10px 16px;
  z-index: 100;
}
.skip-link:focus { left: 8px; top: 8px; }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* ---------- top bar ---------- */
.topbar {
  border-bottom: 1px solid var(--line);
  background: #fff;
  position: sticky;
  top: 0;
  z-index: 20;
}
.topbar .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 60px;
  gap: 16px;
}
.brand {
  font-weight: 700;
  font-size: 17px;
  letter-spacing: .04em;
  color: var(--ink);
}
.brand span {
  display: block;
  font-weight: 400;
  font-size: 12px;
  color: var(--ink-3);
  letter-spacing: .12em;
}
.topnav { display: flex; gap: 20px; font-size: 14px; }
.topnav a { color: var(--ink-2); }

/* ---------- sections ---------- */
section { padding: 64px 0; border-bottom: 1px solid var(--line); }
section.alt { background: var(--bg-2); }
section:last-of-type { border-bottom: 0; }

.eyebrow {
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--ink-3);
  text-transform: uppercase;
  margin: 0 0 12px;
}

h1, h2, h3 { line-height: 1.35; margin: 0 0 16px; letter-spacing: -.01em; }
h1 { font-size: 34px; font-weight: 700; }
h2 { font-size: 24px; font-weight: 700; }
h3 { font-size: 17px; font-weight: 600; }
p { margin: 0 0 14px; color: var(--ink-2); }

.lead { font-size: 17px; color: var(--ink-2); max-width: 42em; }
.muted { color: var(--ink-3); font-size: 14px; }

/* ---------- hero ---------- */
.hero {
  padding: 72px 0 60px;
  position: relative;
  overflow: hidden;
}
/* 蓝图网格纹理：纯 CSS，零请求，不与文字抢对比度 */
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(22, 92, 74, .07) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(22, 92, 74, .07) 1px, transparent 1px),
    linear-gradient(to right, rgba(22, 92, 74, .045) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(22, 92, 74, .045) 1px, transparent 1px);
  background-size: 96px 96px, 96px 96px, 24px 24px, 24px 24px;
  -webkit-mask-image: linear-gradient(to bottom right, #000, transparent 72%);
  mask-image: linear-gradient(to bottom right, #000, transparent 72%);
}
.hero > .wrap { position: relative; }
.hero-grid {
  display: grid;
  grid-template-columns: 1.55fr 1fr;
  gap: 48px;
  align-items: start;
}
.hero h1 { font-size: 38px; }
.hero .tagline {
  font-size: 13px;
  letter-spacing: .16em;
  color: var(--accent);
  margin: 0 0 18px;
  font-weight: 600;
}
.creds {
  list-style: none;
  padding: 0;
  margin: 24px 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 10px;
}
.creds li {
  font-size: 13px;
  color: var(--ink-2);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 3px 12px;
  background: #fff;
}

.contact-card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px;
  background: var(--bg-2);
}
.contact-card h3 { margin-bottom: 4px; font-size: 15px; }
.qr-slot {
  width: 100%;
  aspect-ratio: 1 / 1;
  border: 1px dashed #c6cdd4;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: var(--ink-3);
  font-size: 13px;
  background: #fff;
  margin: 12px 0;
  padding: 12px;
}
.contact-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  font-size: 14px;
  padding: 7px 0;
  border-top: 1px solid var(--line);
}
.contact-row dt { color: var(--ink-3); margin: 0; }
.contact-row dd { margin: 0; font-weight: 600; color: var(--ink); }
.contact-card dl { margin: 12px 0 0; }
.pending { color: var(--ink-3); font-weight: 400; font-style: italic; }

/* ---------- buttons ---------- */
.btn {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  padding: 11px 22px;
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 600;
  border: 1px solid var(--accent);
  cursor: pointer;
  font-family: inherit;
}
.btn:hover { background: #124b3c; text-decoration: none; }
.btn.ghost { background: #fff; color: var(--accent); }
.btn.ghost:hover { background: var(--accent-soft); }
.btn[disabled] { opacity: .6; cursor: progress; }
.btn-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 22px; }

/* ---------- generic grids ---------- */
.grid { display: grid; gap: 20px; }
.g3 { grid-template-columns: repeat(3, 1fr); }
.g2 { grid-template-columns: repeat(2, 1fr); }

.card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
  background: #fff;
}
.card p:last-child { margin-bottom: 0; }
.card .kicker {
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--ink-3);
  margin: 0 0 8px;
}
.card .start {
  margin: 14px 0 0;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  font-size: 14px;
  color: var(--ink-2);
}
.card .start b { color: var(--ink); }

.card .icon {
  width: 46px;
  height: 46px;
  margin: 0 0 14px;
  display: block;
}

/* ---------- pain list ---------- */
.pain { list-style: none; padding: 0; margin: 0; display: grid; gap: 14px; }
.pain li {
  border-left: 3px solid var(--accent);
  padding: 4px 0 4px 16px;
  font-size: 17px;
  color: var(--ink);
}
.pain li span { display: block; font-size: 14px; color: var(--ink-3); margin-top: 2px; }

/* ---------- case ---------- */
.case {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  overflow: hidden;
}
.case-body { padding: 22px; }
.case figure {
  margin: 0;
  border-bottom: 1px solid var(--line);
  background: var(--bg-2);
}
.case figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 8 / 5;
  object-fit: cover;
  background: var(--bg-2);
}
.case h3 { margin-bottom: 10px; }

/* 第三个案例独占一行：图文左右分栏，避免图片被拉成大横幅 */
.case.wide { display: grid; grid-template-columns: 1fr 1fr; align-items: stretch; }
.case.wide figure {
  border-bottom: 0;
  border-right: 1px solid var(--line);
  display: flex;
}
.case.wide figure img { height: 100%; aspect-ratio: auto; min-height: 260px; }
@media (max-width: 860px) {
  .case.wide { grid-template-columns: 1fr; }
  .case.wide figure {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }
  .case.wide figure img { aspect-ratio: 8 / 5; min-height: 0; }
}
.case dl { margin: 0; }
.case dt {
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--ink-3);
  margin-top: 12px;
}
.case dd { margin: 2px 0 0; font-size: 15px; color: var(--ink-2); }
.metrics { list-style: none; padding: 0; margin: 12px 0 0; display: grid; gap: 4px; }
.metrics li { font-size: 14px; color: var(--ink-2); }
.metrics li b { color: var(--ink); }
.disclaimer {
  margin-top: 20px;
  font-size: 13px;
  color: var(--ink-3);
  border-top: 1px solid var(--line);
  padding-top: 14px;
}

/* ---------- guarantee ---------- */
.guarantee { list-style: none; padding: 0; margin: 0; display: grid; gap: 18px; }
.guarantee > li {
  display: grid;
  grid-template-columns: 130px 1fr;
  gap: 20px;
  border-top: 1px solid var(--line);
  padding-top: 16px;
}
.guarantee > li:first-child { border-top: 0; padding-top: 0; }
.guarantee strong { font-size: 15px; }
.guarantee p { margin: 0; }

/* ---------- faq ---------- */
details {
  border-bottom: 1px solid var(--line);
  padding: 14px 0;
}
details summary {
  cursor: pointer;
  font-weight: 600;
  font-size: 16px;
  color: var(--ink);
  list-style: none;
  display: flex;
  justify-content: space-between;
  gap: 12px;
}
details summary::-webkit-details-marker { display: none; }
details summary::after { content: "+"; color: var(--ink-3); font-weight: 400; }
details[open] summary::after { content: "−"; }
details p { margin: 12px 0 0; }

/* ---------- lead form ---------- */
.lead-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: start; }
.bait { list-style: none; padding: 0; margin: 18px 0 0; display: grid; gap: 8px; }
.bait li { font-size: 15px; color: var(--ink-2); padding-left: 22px; position: relative; }
.bait li::before { content: "—"; position: absolute; left: 0; color: var(--accent); }

form { display: grid; gap: 14px; }
.field { display: grid; gap: 6px; }
label { font-size: 14px; font-weight: 600; color: var(--ink); }
label .opt { font-weight: 400; color: var(--ink-3); }
input, textarea {
  font-family: inherit;
  font-size: 16px;
  padding: 10px 12px;
  border: 1px solid #c6cdd4;
  border-radius: var(--radius);
  background: #fff;
  color: var(--ink);
  width: 100%;
}
textarea { resize: vertical; min-height: 84px; }
input:focus, textarea:focus { border-color: var(--accent); outline: none; box-shadow: 0 0 0 3px var(--accent-soft); }
.hp { position: absolute; left: -9999px; width: 1px; height: 1px; overflow: hidden; }
.form-note { font-size: 13px; color: var(--ink-3); margin: 0; }
.form-msg { font-size: 14px; margin: 0; min-height: 1.4em; }
.form-msg.err { color: #a3271f; }
.form-msg.ok { color: var(--accent); }
.done {
  border: 1px solid var(--accent);
  background: var(--accent-soft);
  border-radius: var(--radius);
  padding: 22px;
}
.done h3 { margin-bottom: 8px; }
.done p:last-child { margin-bottom: 0; }

/* ---------- footer ---------- */
footer {
  background: var(--ink);
  color: #aab4bd;
  padding: 36px 0;
  font-size: 14px;
}
footer .wrap { display: flex; justify-content: space-between; gap: 20px; flex-wrap: wrap; }
footer strong { color: #fff; display: block; margin-bottom: 4px; }
footer a { color: #cfd6dc; }

/* ---------- responsive ---------- */
@media (max-width: 860px) {
  .hero-grid, .lead-grid { grid-template-columns: 1fr; gap: 28px; }
  .g3, .g2 { grid-template-columns: 1fr; }
  .guarantee > li { grid-template-columns: 1fr; gap: 6px; }
  h1, .hero h1 { font-size: 28px; }
  h2 { font-size: 21px; }
  section { padding: 48px 0; }
  .topnav { display: none; }

  /* 手机：点击区不小于 44px */
  details { padding: 0; }
  details summary {
    min-height: 44px;
    padding: 12px 0;
    align-items: center;
    font-size: 16px;
  }
  details p { padding-bottom: 14px; }

  /* 手机：正文小字发大，中文 13px 在手机上偏吃力 */
  .creds li { font-size: 14px; padding: 5px 13px; }
  .hero .tagline { font-size: 14px; }
  .muted, .form-note, .disclaimer, .pain li span { font-size: 14px; }
  .metrics li, .contact-row { font-size: 15px; }

  /* 手机：按钮撑清，拇指好点 */
  .btn { display: block; width: 100%; text-align: center; padding: 14px 22px; }
  .btn-row { gap: 10px; }

  /* 手机：页脚链接抹开，别挤成一堆 */
  footer .wrap { flex-direction: column; gap: 22px; }
  footer a { display: inline-block; min-height: 44px; line-height: 44px; }

  /* 手机：二维码不必占满屏宽 */
  .qr-slot { max-width: 240px; margin-inline: auto; }
}

@media print {
  .topbar, footer, form { display: none; }
}