/* root: classic centered product frame */
:root {
  --ink: #111B21;
  --paper: #F0F2F5;
  --teal: #128C7E;
  --mint: #25D366;
  --deep: #075E54;
  --card: #ffffff;
  --line: #d5dce0;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: auto; }
body {
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.7;
  color: var(--ink);
  background: var(--paper);
}
img, svg { max-width: 100%; display: block; }
a { color: var(--deep); text-decoration: none; }
a:hover { color: var(--teal); }

.mast {
  background: var(--deep);
  color: #fff;
  position: sticky;
  top: 0;
  z-index: 20;
}
.mast-inner {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 68px;
}
.brand-lock {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  font-weight: 700;
  font-size: 18px;
  white-space: nowrap;
}
.brand-lock svg { width: 32px; height: 32px; flex-shrink: 0; }
.jump-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 14px;
  justify-content: flex-end;
}
.jump-nav a {
  color: #d7efe8;
  font-size: 13px;
  padding: 6px 10px;
  border-radius: 999px;
}
.jump-nav a:hover {
  background: rgba(37, 211, 102, 0.22);
  color: #fff;
}

.stage {
  background: linear-gradient(180deg, #075E54 0%, #128C7E 58%, #F0F2F5 58%);
  padding: 48px 0 28px;
}
.stage-inner {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 36px;
  align-items: center;
}
.stage h1 {
  font-size: 34px;
  line-height: 1.35;
  color: #fff;
  margin-bottom: 16px;
  font-weight: 700;
}
.stage p {
  color: #e8f7f2;
  margin-bottom: 12px;
  max-width: 36em;
}
.browser-frame {
  background: #fff;
  border-radius: 10px;
  box-shadow: 0 18px 40px rgba(7, 94, 84, 0.28);
  overflow: hidden;
}
.browser-bar {
  background: #e8eaed;
  height: 36px;
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 0 12px;
}
.browser-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: #c4c7cc;
}
.browser-url {
  flex: 1;
  height: 20px;
  background: #fff;
  border-radius: 4px;
  margin-left: 8px;
}
.chat-mock {
  display: grid;
  grid-template-columns: 38% 62%;
  min-height: 220px;
}
.chat-side { background: #f6f7f8; padding: 12px; }
.chat-row {
  height: 28px;
  background: #e3e6ea;
  border-radius: 6px;
  margin-bottom: 8px;
}
.chat-main { background: #efeae2; padding: 16px; }
.bubble {
  max-width: 78%;
  padding: 8px 10px;
  border-radius: 8px;
  margin-bottom: 8px;
  height: 34px;
}
.bubble-in { background: #fff; }
.bubble-out { background: #d9fdd3; margin-left: auto; }

.wrap {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  padding: 8px 0 48px;
}
.block { padding: 42px 0 8px; }
.block h2 {
  font-size: 26px;
  color: var(--deep);
  margin-bottom: 14px;
  line-height: 1.4;
}
.lead {
  margin-bottom: 20px;
  color: #1f2c33;
}

.trio {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
.trio-card {
  background: var(--card);
  border-radius: 8px;
  padding: 22px 20px 20px;
  border-top: 4px solid var(--mint);
  box-shadow: 0 1px 0 rgba(17, 27, 33, 0.06);
}
.trio-card h3 {
  font-size: 18px;
  margin: 12px 0 8px;
}
.ico {
  width: 40px;
  height: 40px;
  color: var(--teal);
}

.kind-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}
.kind-cell {
  background: #fff;
  border-radius: 8px;
  padding: 18px 16px;
  border: 1px solid #e2e6ea;
}
.kind-cell h3 { font-size: 17px; margin: 10px 0 8px; }
.kind-cell svg { width: 36px; height: 36px; color: var(--deep); }

.duo-pane {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}
.duo-card {
  background: #fff;
  border-radius: 8px;
  padding: 22px;
  border-left: 6px solid var(--teal);
}
.duo-card h3 { margin-bottom: 10px; font-size: 18px; }
.duo-card ul { padding-left: 18px; }
.duo-card li { margin: 8px 0; }

.rail-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  background: #fff;
  border-radius: 8px;
  overflow: hidden;
  border: 1px solid #dce3e6;
}
.rail-item {
  padding: 20px 16px 22px;
  position: relative;
}
.rail-item + .rail-item { border-left: 1px solid #dce3e6; }
.rail-num {
  display: inline-block;
  width: 28px;
  height: 28px;
  line-height: 28px;
  text-align: center;
  background: var(--mint);
  color: #113322;
  font-weight: 700;
  border-radius: 4px;
  margin-bottom: 10px;
  font-size: 14px;
}
.rail-item h3 { font-size: 16px; margin-bottom: 8px; }

.diff-board {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  border-radius: 8px;
  overflow: hidden;
}
.diff-board th,
.diff-board td {
  border: 1px solid #d8dee2;
  padding: 12px 14px;
  text-align: left;
  vertical-align: top;
}
.diff-board th {
  background: var(--teal);
  color: #fff;
  font-weight: 600;
}
.diff-board tr:nth-child(even) td { background: #f4fbf8; }

.stay-cards { display: grid; gap: 12px; }
.stay-item {
  background: #fff;
  border-radius: 8px;
  padding: 16px 18px;
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 12px;
  align-items: start;
  border: 1px solid #e1e6ea;
}
.stay-item h3 { font-size: 17px; margin-bottom: 6px; }
.stay-item svg { width: 36px; height: 36px; color: var(--deep); }

.faq-fold { display: grid; gap: 10px; }
.faq-fold details {
  background: #fff;
  border-radius: 8px;
  border: 1px solid #dce3e6;
  padding: 4px 16px 4px;
}
.faq-fold summary {
  cursor: pointer;
  font-weight: 650;
  padding: 12px 0;
  list-style: none;
}
.faq-fold summary::-webkit-details-marker { display: none; }
.faq-fold summary:hover { color: var(--teal); }
.faq-fold details p { padding-bottom: 14px; }

.base-foot {
  background: #111B21;
  color: #c7d0d4;
  padding: 36px 0 28px;
  font-size: 14px;
}
.base-foot .wrap { padding-bottom: 0; }
.base-foot p { margin: 8px 0; }
.base-foot strong { color: #fff; font-weight: 600; }

@media (max-width: 900px) {
  .stage-inner, .trio, .kind-grid, .duo-pane, .rail-steps {
    grid-template-columns: 1fr;
  }
  .rail-item + .rail-item { border-left: 0; border-top: 1px solid #dce3e6; }
  .mast-inner { flex-direction: column; padding: 12px 0; }
  .stage h1 { font-size: 26px; }
}