/* app：选型驱动 — 应用顶栏、四宫格、底部固定操作条 */
:root {
  --bg: #ecf0f1;
  --ink: #2c3e50;
  --hot: #d35400;
  --hot2: #e67e22;
  --card: #ffffff;
}
html { box-sizing: border-box; }
*, *:before, *:after { box-sizing: inherit; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: Tahoma, "Microsoft YaHei", sans-serif;
  line-height: 1.62;
  padding-bottom: 72px;
}

.appbar {
  background: var(--ink);
  color: #fff;
  height: 56px;
  display: flex;
  align-items: center;
  padding: 0 18px;
  justify-content: space-between;
}
.appbar a.b {
  color: #fff;
  font-weight: 800;
  text-decoration: none;
  font-size: 1.05rem;
}
.appbar nav a {
  color: #d5dde4;
  text-decoration: none;
  margin-left: 14px;
  font-size: 0.88rem;
}
.appbar nav a.sel { color: var(--hot2); font-weight: 700; }

.hero-app {
  background: linear-gradient(90deg, var(--hot), #b84300);
  color: #fff;
  padding: 36px 18px 28px;
}
.hero-app h1 { margin: 0 0 10px; font-size: 1.6rem; }
.hero-app p { margin: 0 0 16px; max-width: 46em; opacity: 0.95; }
.hero-app .btn {
  background: #fff;
  color: var(--hot);
  text-decoration: none;
  padding: 11px 20px;
  font-weight: 800;
  display: inline-block;
}

.quad {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
  width: min(1100px, 94vw);
  margin: -18px auto 0;
}
.quad article {
  background: var(--card);
  padding: 14px 12px;
  box-shadow: 0 2px 0 rgba(44, 62, 80, 0.12);
}
.quad svg { width: 22px; height: 22px; fill: var(--hot); }
.quad h2 { font-size: 0.95rem; margin: 8px 0 6px; }
.quad p { margin: 0; font-size: 0.82rem; }

.sheet {
  width: min(1100px, 94vw);
  margin: 22px auto;
  background: var(--card);
  padding: 20px 22px;
  box-shadow: 0 1px 0 rgba(44, 62, 80, 0.1);
}
.sheet h2 {
  margin: 0 0 12px;
  font-size: 1.2rem;
  color: var(--hot);
}
.sheet p { margin: 0 0 10px; }
.sheet ul, .sheet ol { margin: 0 0 10px 1.2em; }
.pick {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}
.pick div {
  border: 2px solid #d5dce0;
  padding: 12px 14px;
}
.pick h3 { margin: 0 0 8px; font-size: 1rem; }
table.mat {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}
table.mat th { background: var(--ink); color: #fff; padding: 8px; text-align: left; }
table.mat td { border: 1px solid #d5dce0; padding: 8px; }
.riskbox {
  background: #fdeee6;
  border-left: 6px solid var(--hot);
}
.dl a {
  display: inline-block;
  background: var(--ink);
  color: #fff;
  text-decoration: none;
  padding: 8px 12px;
  margin: 4px 4px 4px 0;
  font-size: 0.88rem;
}
.faq-app h3 { font-size: 0.98rem; margin: 12px 0 4px; }
.faq-app p { color: #4a5a68; }

.dock {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--ink);
  color: #fff;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 16px;
  z-index: 30;
}
.dock a {
  background: var(--hot);
  color: #fff;
  text-decoration: none;
  padding: 8px 16px;
  font-weight: 700;
}

.fin {
  background: #1b2836;
  color: #b0bcc6;
  padding: 26px 5vw 90px;
  font-size: 0.84rem;
}
.fin p { margin: 0 0 8px; }
.fin a { color: #e67e22; }

@media (max-width: 900px) {
  .quad { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 560px) {
  .quad, .pick { grid-template-columns: 1fr; }
  .appbar { height: auto; padding: 10px 12px; flex-wrap: wrap; }
}