/* 「千语界」官网样式（纯静态、零依赖） */
:root {
  --brand: #3d56c4;
  --brand-soft: #eef1ff;
  --text: #1f2430;
  --text-soft: #5b6478;
  --line: #e6e9f2;
  --bg: #ffffff;
  --bg-soft: #f7f8fc;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
/* 锚点跳转时给吸顶导航留出高度 */
section[id] { scroll-margin-top: 64px; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
}

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

.container { max-width: 980px; margin: 0 auto; padding: 0 20px; }

/* ===== 顶部栏 ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255, 255, 255, .92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  padding-top: 10px;
  padding-bottom: 10px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 17px;
  color: var(--text);
}
.brand img { border-radius: 8px; }
.nav { display: flex; gap: 12px; flex-wrap: wrap; margin-left: auto; font-size: 14px; }
.nav a { color: var(--text-soft); }
.nav a:hover { color: var(--brand); }
.lang-switch { display: flex; align-items: center; gap: 2px; font-size: 13px; }
.lang-switch a { color: var(--text-soft); padding: 3px 6px; border-radius: 999px; }
.lang-switch a:hover { color: var(--brand); text-decoration: none; }
.lang-switch a.active { color: var(--brand); background: var(--brand-soft); }

/* ===== 首屏 ===== */
.hero {
  padding: 64px 0 48px;
  text-align: center;
  background: linear-gradient(180deg, var(--brand-soft) 0%, rgba(238, 241, 255, 0) 100%);
}
.hero-logo { border-radius: 24px; box-shadow: 0 10px 30px rgba(61, 86, 196, .18); }
.hero h1 { margin: 18px 0 8px; font-size: 40px; letter-spacing: 2px; }
.tagline { margin: 0 auto; max-width: 620px; color: var(--text-soft); font-size: 16px; }
.chips { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; margin-top: 20px; }
.chips span {
  background: #fff;
  border: 1px solid var(--line);
  color: var(--brand);
  border-radius: 999px;
  padding: 4px 14px;
  font-size: 13px;
}
.hero-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 22px;
}
.btn {
  display: inline-block;
  padding: 10px 22px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  border: 1px solid transparent;
}
.btn.primary {
  background: var(--brand);
  color: #fff;
  box-shadow: 0 6px 16px rgba(61, 86, 196, .28);
}
.btn.primary:hover {
  text-decoration: none;
  background: #3550b8;
}
.btn.ghost {
  border-color: var(--line);
  color: var(--brand);
  background: #fff;
}
.btn.ghost:hover {
  text-decoration: none;
  border-color: var(--brand);
}

/* ===== 通用区块 ===== */
.section { padding: 56px 0; }
.section.alt { background: var(--bg-soft); }
.section h2 {
  font-size: 24px;
  margin: 0 0 24px;
  position: relative;
  padding-left: 14px;
}
.section h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  bottom: 6px;
  width: 4px;
  border-radius: 2px;
  background: var(--brand);
}

/* ===== 功能卡片 ===== */
.feature-grid {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}
.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 20px;
  transition: transform .15s ease, box-shadow .15s ease;
}
.card:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 24px rgba(31, 36, 48, .08);
}
.card .ico {
  width: 42px;
  height: 42px;
  border-radius: 12px;
  background: var(--brand-soft);
  color: var(--brand);
  display: flex;
  align-items: center;
  justify-content: center;
}
.card .ico svg { width: 22px; height: 22px; display: block; }
.card h3 { margin: 12px 0 6px; font-size: 17px; }
.card p { margin: 0; color: var(--text-soft); font-size: 14px; }

/* ===== 内容要点 ===== */
.points { list-style: none; padding: 0; margin: 0; display: grid; gap: 12px; }
.points li {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 14px 18px;
  font-size: 15px;
  color: var(--text-soft);
}
.points strong { color: var(--text); }

/* ===== 常见问题 ===== */
.faq details {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 14px 18px;
  margin-bottom: 10px;
}
.faq summary {
  cursor: pointer;
  font-weight: 600;
  font-size: 15px;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+";
  color: var(--brand);
  font-weight: 700;
  font-size: 18px;
  line-height: 1;
}
.faq details[open] summary::after { content: "−"; }
.faq p {
  margin: 10px 0 2px;
  color: var(--text-soft);
  font-size: 14px;
}

/* ===== 应用截图画廊 ===== */
.shots {
  display: grid;
  gap: 22px;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  align-items: start;
}
.shot { margin: 0; text-align: center; }
.shot-frame {
  width: 100%;
  max-width: 300px;
  margin: 0 auto;
  border-radius: 18px;
  border: 1px solid var(--line);
  background: #0f1116;
  box-shadow: 0 14px 30px rgba(31, 36, 48, .16);
}
.shot-frame img {
  display: block;
  width: 100%;
  border-radius: 17px;
  cursor: zoom-in;
  transition: transform .18s ease;
}
.shot img.zooming {
  position: relative;
  z-index: 1001;
  cursor: zoom-out;
  border-radius: 12px;
  box-shadow: 0 24px 80px rgba(0, 0, 0, .55);
}
.shot-backdrop {
  position: fixed;
  inset: 0;
  z-index: 1000;
  background: rgba(15, 17, 22, .82);
  opacity: 0;
  pointer-events: none;
  transition: opacity .18s ease;
}
.shot-backdrop.on { opacity: 1; }
.shot-todo { display: none; }
.shot.missing .shot-frame {
  background: linear-gradient(160deg, #f2f4fb, #e7ebf7);
  border-style: dashed;
}
.shot.missing .shot-frame img { display: none; }
.shot.missing .shot-todo {
  display: flex;
  align-items: center;
  justify-content: center;
  aspect-ratio: 16 / 9;
  color: #8d95a8;
  font-size: 13px;
}
.shot figcaption {
  margin-top: 10px;
  font-size: 13px;
  color: var(--text-soft);
}

/* ===== 占位标记（提交前替换，详见 README） ===== */
.todo {
  color: #9a6b00;
  background: #fff6df;
  border-bottom: 1px dashed #d9a300;
  border-radius: 3px;
  padding: 0 4px;
}

/* ===== 页脚 ===== */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 28px 0 44px;
  color: #6b7280;
  font-size: 13px;
}
.footer-links { margin: 0 0 8px; }
.site-footer .icp { margin: 4px 0 8px; font-size: 12px; }
.site-footer .icp a { color: inherit; }

/* ===== 隐私政策 / 用户协议等文档页 ===== */
.doc { padding: 40px 0 64px; }
.doc h1 { font-size: 28px; margin: 0 0 6px; }
.doc .updated { color: var(--text-soft); font-size: 14px; margin: 0 0 28px; }
.doc h2 { font-size: 18px; margin: 28px 0 10px; }
.doc p, .doc li { color: #333a4a; font-size: 15px; }
.doc ol, .doc ul { padding-left: 22px; }