/* 大厂风格下载页 — 简洁、高对比、易扫读 */
:root {
  --bg: #f5f7fb;
  --surface: #ffffff;
  --text: #1a1a2e;
  --muted: #5c6370;
  --border: #e8ecf2;
  --primary: var(--theme, #0d47a1);
  --primary-hover: #1565c0;
  --shadow: 0 12px 40px rgba(13, 71, 161, 0.08);
  --radius: 16px;
  --font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--primary);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.wrap {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

/* 顶栏 */
.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.topbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 600;
  font-size: 18px;
  color: var(--text);
  text-decoration: none;
}

.brand:hover {
  text-decoration: none;
  opacity: 0.9;
}

.brand img {
  width: 36px;
  height: 36px;
  border-radius: 9px;
}

.top-meta {
  font-size: 13px;
  color: var(--muted);
}

/* Hero */
.hero {
  padding: 56px 0 72px;
  background: linear-gradient(180deg, #e8eef8 0%, var(--bg) 55%);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 48px;
  align-items: center;
}

@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-actions {
    justify-content: center;
  }

  .version-line {
    justify-content: center;
  }
}

.hero h1 {
  margin: 0 0 12px;
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.2;
}

.hero .sub {
  margin: 0 0 24px;
  font-size: 17px;
  color: var(--muted);
  max-width: 520px;
}

@media (max-width: 900px) {
  .hero .sub {
    margin-left: auto;
    margin-right: auto;
  }
}

.version-line {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 20px;
  margin-bottom: 28px;
  font-size: 14px;
  color: var(--muted);
}

.version-line span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.version-line strong {
  color: var(--text);
  font-weight: 600;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 24px;
  border-radius: 12px;
  font-size: 15px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
  text-decoration: none;
}

.btn:hover {
  text-decoration: none;
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 4px 14px rgba(13, 71, 161, 0.35);
}

.btn-primary:hover {
  background: var(--primary-hover);
  color: #fff;
}

.btn-secondary {
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}

.btn-secondary:hover {
  border-color: #cfd6e0;
  color: var(--text);
}

.btn svg {
  flex-shrink: 0;
}

/* APK：网页无法下载后自动安装，仅作说明 */
.apk-note {
  flex-basis: 100%;
  margin: 8px 0 0;
  max-width: 520px;
  font-size: 13px;
  line-height: 1.55;
  color: var(--muted);
  text-align: left;
}

@media (max-width: 900px) {
  .apk-note {
    text-align: center;
    margin-left: auto;
    margin-right: auto;
  }
}

/* 手机展示区 */
.phone-stage {
  display: flex;
  justify-content: center;
}

.phone {
  width: 260px;
  height: 520px;
  background: linear-gradient(145deg, #1e293b 0%, #0f172a 100%);
  border-radius: 36px;
  padding: 12px;
  box-shadow: var(--shadow), 0 0 0 1px rgba(255, 255, 255, 0.06) inset;
  position: relative;
}

.phone-notch {
  position: absolute;
  top: 12px;
  left: 50%;
  transform: translateX(-50%);
  width: 100px;
  height: 28px;
  background: #0f172a;
  border-radius: 0 0 16px 16px;
  z-index: 2;
}

.phone-screen {
  width: 100%;
  height: 100%;
  background: linear-gradient(160deg, #e3f2fd 0%, #fff 45%, #f5f5f5 100%);
  border-radius: 28px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding-top: 48px;
}

.phone-screen .mini-logo {
  width: 72px;
  height: 72px;
  border-radius: 18px;
  margin-bottom: 16px;
  box-shadow: 0 8px 24px rgba(13, 71, 161, 0.2);
}

.phone-screen .mini-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
}

.phone-screen .mini-sub {
  font-size: 13px;
  color: var(--muted);
  margin-top: 6px;
}

.phone-bar {
  margin-top: auto;
  width: 100%;
  height: 4px;
  background: rgba(0, 0, 0, 0.08);
  border-radius: 2px;
  margin: 32px 48px 16px;
}

/* 下载区 */
.download-section {
  padding: 48px 0 64px;
}

.section-title {
  text-align: center;
  margin: 0 0 8px;
  font-size: 24px;
  font-weight: 700;
}

.section-desc {
  text-align: center;
  margin: 0 0 40px;
  color: var(--muted);
  font-size: 15px;
}

.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

@media (max-width: 768px) {
  .cards {
    grid-template-columns: 1fr;
  }
}

.card {
  background: var(--surface);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  padding: 28px 24px;
  text-align: center;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.04);
}

.card h3 {
  margin: 0 0 8px;
  font-size: 17px;
}

.card p {
  margin: 0 0 20px;
  font-size: 14px;
  color: var(--muted);
  min-height: 44px;
}

.qr-wrap {
  display: inline-block;
  padding: 10px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 12px;
}

.qr-wrap img {
  display: block;
  width: 160px;
  height: 160px;
}

.qr-hint {
  margin-top: 12px;
  font-size: 12px;
  color: var(--muted);
}

/* 特性 */
.features {
  padding: 32px 0 64px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

@media (max-width: 900px) {
  .feature-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 480px) {
  .feature-grid {
    grid-template-columns: 1fr;
  }
}

.feature-item {
  background: var(--surface);
  border-radius: 12px;
  padding: 22px 18px;
  border: 1px solid var(--border);
}

.feature-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: linear-gradient(135deg, #e3f2fd, #bbdefb);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 12px;
  font-size: 20px;
}

.feature-item h4 {
  margin: 0 0 6px;
  font-size: 15px;
}

.feature-item p {
  margin: 0;
  font-size: 13px;
  color: var(--muted);
  line-height: 1.5;
}

/* 页脚 */
.footer {
  border-top: 1px solid var(--border);
  background: #fff;
  padding: 32px 0;
  text-align: center;
  font-size: 13px;
  color: var(--muted);
}

.footer-links {
  margin-bottom: 12px;
}

.footer-links a {
  margin: 0 12px;
  color: var(--muted);
}

.footer-links a:hover {
  color: var(--primary);
}