/* 闻见学堂官网样式 —— 纸质感 / 书卷气 / 暖色调 */
:root {
  --primary: #8b5e3c;        /* 赭棕 主色 */
  --primary-deep: #6e4526;
  --ink: #3b3226;            /* 墨棕 正文 */
  --ink-light: #857a69;
  --paper: #faf6ef;          /* 米纸背景 */
  --card: #fffdf8;
  --line: #e9dfd0;
  --green: #3e5c50;          /* 黛绿 点缀 */
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  background: var(--paper);
  color: var(--ink);
  line-height: 1.85;
  -webkit-font-smoothing: antialiased;
}
h1, h2, h3, .brand, .btn-store {
  font-family: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", SimSun, serif;
}
a { text-decoration: none; color: inherit; }
.container { max-width: 1060px; margin: 0 auto; padding: 0 22px; }

/* ===== 顶栏 ===== */
header.site {
  position: sticky; top: 0; z-index: 20;
  background: rgba(250, 246, 239, .94);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(6px);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 62px; }
.brand { display: flex; align-items: center; gap: 10px; font-size: 20px; font-weight: 700; color: var(--primary-deep); letter-spacing: 2px; }
.brand svg { display: block; }
nav.links { display: flex; gap: 26px; font-size: 15px; }
nav.links a { color: var(--ink-light); }
nav.links a:hover { color: var(--primary); }
@media (max-width: 680px) { nav.links { display: none; } }

/* ===== 首屏 ===== */
.hero { padding: 78px 0 84px; }
.hero .container { display: flex; align-items: center; justify-content: space-between; gap: 40px; }
.hero-text { max-width: 520px; }
.hero-text .kicker {
  display: inline-block; font-size: 13px; letter-spacing: 4px;
  color: var(--green); border: 1px solid #cfdcd5; border-radius: 999px;
  padding: 4px 14px; margin-bottom: 22px; background: #f1f4ee;
}
.hero-text h1 { font-size: 40px; line-height: 1.4; letter-spacing: 2px; margin-bottom: 18px; }
.hero-text h1 em { font-style: normal; color: var(--primary); }
.hero-text p { font-size: 16px; color: var(--ink-light); max-width: 440px; }
.hero-note { margin-top: 26px; font-size: 13px; color: #a89a85; letter-spacing: 1px; }
@media (max-width: 900px) {
  .hero { padding: 52px 0 60px; }
  .hero .container { flex-direction: column; text-align: center; }
  .hero-text h1 { font-size: 30px; }
  .hero-text p { margin: 0 auto; }
}

/* 手机模型（截图占位） */
.phone-wrap { flex-shrink: 0; }
.phone {
  width: 252px; height: 508px; border-radius: 38px;
  background: #33291f; padding: 11px;
  box-shadow: 0 24px 48px rgba(80, 60, 35, .22), inset 0 0 0 2px #4a3b2c;
}
.phone-screen {
  width: 100%; height: 100%; border-radius: 28px; overflow: hidden;
  background: linear-gradient(175deg, #fdf9f1 0%, #f4ead9 100%);
  position: relative;
  display: flex; flex-direction: column; align-items: center;
}
.phone-notch { width: 84px; height: 20px; background: #33291f; border-radius: 0 0 14px 14px; }
.album {
  width: 132px; height: 132px; border-radius: 18px; margin-top: 34px;
  background: linear-gradient(135deg, #b98a5e, #8b5e3c);
  box-shadow: 0 10px 22px rgba(110, 69, 38, .3);
  position: relative;
}
.album::after {
  content: ""; position: absolute; inset: 0; margin: auto;
  width: 34px; height: 34px; border-radius: 50%;
  border: 3px solid rgba(255, 251, 243, .9);
}
.album-title { margin-top: 18px; font-size: 14px; color: var(--ink); letter-spacing: 1px; }
.album-sub { font-size: 11px; color: #a89a85; margin-top: 2px; }
.playbar { width: 74%; margin-top: 20px; }
.playbar .track { height: 4px; border-radius: 2px; background: #e5d8c2; position: relative; }
.playbar .track::before { content: ""; position: absolute; left: 0; top: 0; height: 100%; width: 42%; border-radius: 2px; background: var(--primary); }
.playbar .time { display: flex; justify-content: space-between; font-size: 10px; color: #b3a68f; margin-top: 5px; }
.play-ctrl { display: flex; align-items: center; gap: 26px; margin-top: 16px; }
.play-ctrl .dot { width: 8px; height: 8px; border-radius: 50%; background: #cdbfa6; }
.play-ctrl .play {
  width: 46px; height: 46px; border-radius: 50%; background: var(--primary);
  position: relative; box-shadow: 0 6px 14px rgba(139, 94, 60, .4);
}
.play-ctrl .play::after {
  content: ""; position: absolute; inset: 0; margin: auto;
  border-style: solid; border-width: 8px 0 8px 13px; border-color: transparent transparent transparent #fdf9f1;
  transform: translateX(2px);
}
.phone-tip {
  position: absolute; bottom: 12px; font-size: 10px; color: #c4b49a; letter-spacing: 1px;
}

/* ===== 区块标题 ===== */
.section-head { text-align: center; margin-bottom: 46px; }
.section-head h2 { font-size: 27px; letter-spacing: 3px; color: var(--primary-deep); }
.section-head .en { font-size: 12px; letter-spacing: 5px; color: #b3a68f; margin-top: 6px; text-transform: uppercase; }
.section-head .rule { width: 42px; height: 2px; background: var(--primary); margin: 16px auto 0; opacity: .55; }

/* ===== 功能卡片 ===== */
.features { padding: 66px 0 72px; }
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
@media (max-width: 900px) { .cards { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 560px) { .cards { grid-template-columns: 1fr; } }
.card {
  background: var(--card); border: 1px solid var(--line); border-radius: 14px;
  padding: 30px 24px; text-align: center;
  transition: transform .2s ease, box-shadow .2s ease;
}
.card:hover { transform: translateY(-4px); box-shadow: 0 12px 26px rgba(110, 69, 38, .1); }
.card .zi {
  width: 48px; height: 48px; border-radius: 50%; margin: 0 auto 16px;
  background: #f4ead9; color: var(--primary-deep);
  font-family: "Noto Serif SC", "Songti SC", SimSun, serif;
  font-size: 20px; display: flex; align-items: center; justify-content: center;
  border: 1px solid #e8d9c0;
}
.card h3 { font-size: 17px; letter-spacing: 1px; margin-bottom: 8px; }
.card p { font-size: 13.5px; color: var(--ink-light); }

/* ===== 下载区 ===== */
.download { padding: 66px 0 80px; background: linear-gradient(180deg, #f3ecdf, #efe5d2); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.download .tip { text-align: center; font-size: 14px; color: var(--ink-light); margin-bottom: 34px; }
.stores { display: flex; justify-content: center; gap: 18px; flex-wrap: wrap; }
.btn-store {
  display: flex; align-items: center; gap: 13px;
  min-width: 196px; padding: 14px 22px; border-radius: 14px;
  background: var(--card); border: 1px solid var(--line);
  color: var(--ink); cursor: default;
  transition: transform .2s ease, box-shadow .2s ease;
}
.btn-store:hover { transform: translateY(-3px); box-shadow: 0 10px 22px rgba(110, 69, 38, .13); }
.btn-store .ico { width: 36px; height: 36px; border-radius: 10px; display: flex; align-items: center; justify-content: center; flex-shrink: 0; }
.btn-store .ico svg { display: block; }
.btn-store .t1 { font-size: 16px; font-weight: 700; letter-spacing: 1px; }
.btn-store .t2 { font-size: 11.5px; color: #a89a85; letter-spacing: 1px; }

/* ===== 页脚 ===== */
footer.site { background: #2f271d; color: #a2937d; font-size: 13.5px; padding: 34px 20px 38px; text-align: center; }
footer.site .foot-nav { margin-bottom: 10px; }
footer.site .foot-nav a { color: #c3b49b; }
footer.site .foot-nav a:hover { color: #ffffff; }
footer.site .foot-nav .sep { margin: 0 10px; color: #55483a; }
footer.site .beian { margin-top: 8px; }
footer.site .beian a { color: #a2937d; }
footer.site .beian a:hover { color: #ffffff; }
footer.site .beian .sep { margin: 0 10px; color: #55483a; }
footer.site .copyright { margin-top: 8px; letter-spacing: 1px; }

/* ===== 文档页（隐私政策 / 用户协议） ===== */
.doc-wrap { padding: 54px 0 70px; }
.doc { background: var(--card); border: 1px solid var(--line); border-radius: 16px; max-width: 860px; margin: 0 auto; padding: 48px 54px; }
@media (max-width: 680px) { .doc { padding: 34px 22px; } }
.doc h1 { font-size: 26px; letter-spacing: 2px; color: var(--primary-deep); text-align: center; margin-bottom: 6px; }
.doc .doc-meta { text-align: center; font-size: 13px; color: #a89a85; margin-bottom: 30px; }
.doc h2 { font-size: 17.5px; color: var(--primary-deep); margin: 28px 0 10px; letter-spacing: 1px; }
.doc p, .doc li { font-size: 14.5px; color: #52483a; margin-bottom: 8px; }
.doc ul { padding-left: 22px; margin-bottom: 10px; }
.doc table { width: 100%; border-collapse: collapse; margin: 12px 0 16px; font-size: 13.5px; }
.doc th, .doc td { border: 1px solid var(--line); padding: 9px 12px; text-align: left; color: #52483a; }
.doc th { background: #f6efe3; color: var(--primary-deep); font-weight: 600; }
.doc .muted { color: #a89a85; font-size: 13px; }
.doc strong { color: var(--primary-deep); }