/* ============ 配色变量（沿用原站蓝色主题） ============ */
:root {
  --deep-blue: #1A237E;   /* 深蓝 - 头部/页脚 */
  --medium-blue: #3F51B5; /* 中蓝 - 标题/强调色 */
  --light-blue: #E3F2FD;  /* 浅蓝 - 内容背景 */
  --accent-blue: #1E90FF; /* 道奇蓝 - 交互元素 */
  --text-dark: #222;
  --text-mid: #555;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  background: #f5f8fc;
  color: var(--text-dark);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { text-decoration: none; color: inherit; }
ul { list-style: none; }

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ============ 顶部导航 ============ */
.site-nav {
  background: var(--deep-blue);
  color: #fff;
}

.nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  min-height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
}

.nav-left {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 0;
}

.logo-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: var(--accent-blue);
  border-radius: 8px;
  font-size: 20px;
  font-weight: 700;
  color: #fff;
  flex-shrink: 0;
}

.nav-prime {
  font-size: 20px;
  font-weight: 700;
  white-space: nowrap;
}

.nav-slog {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.78);
  margin-left: 6px;
  padding-left: 14px;
  border-left: 1px solid rgba(255, 255, 255, 0.3);
  white-space: nowrap;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 12px 0;
  flex-wrap: wrap;
}

.nav-links a {
  font-size: 14px;
  color: #fff;
  padding: 6px 12px;
  border-radius: 6px;
  transition: background 0.2s;
}
.nav-links a:hover { background: rgba(255, 255, 255, 0.15); }
.nav-links a.current {
  background: var(--accent-blue);
  font-weight: 600;
}

/* ============ Hero 区 ============ */
.hero {
  background: linear-gradient(160deg, #fff 0%, var(--light-blue) 100%);
  padding: 60px 20px;
}

.hero-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 50px;
  flex-wrap: wrap;
}

.hero-pic {
  flex: 0 0 300px;
  display: flex;
  justify-content: center;
}

.pic-placeholder {
  width: 220px;
  height: 220px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 100px;
  background: #fff;
  border-radius: 28px;
  box-shadow: 0 14px 40px rgba(30, 144, 255, 0.18);
  border: 1px solid #dbeafe;
}

.hero-intro { flex: 1; min-width: 280px; }

.hero-title {
  font-size: clamp(28px, 4vw, 40px);
  color: var(--deep-blue);
  font-weight: 800;
  margin-bottom: 18px;
}

.hero-slogan {
  font-size: clamp(18px, 2.6vw, 24px);
  color: var(--text-mid);
  line-height: 1.6;
  margin-bottom: 30px;
}
.hero-slogan em {
  font-style: normal;
  color: var(--accent-blue);
  font-weight: 700;
}

.download { display: inline-block; }

.downbt {
  display: inline-block;
  background: var(--accent-blue);
  color: #fff;
  font-size: 20px;
  font-weight: 700;
  padding: 16px 52px;
  border-radius: 12px;
  text-align: center;
  transition: background 0.2s, transform 0.15s;
  box-shadow: 0 10px 26px rgba(30, 144, 255, 0.35);
}
.downbt:hover { background: #1873d0; transform: translateY(-2px); }
.downbt p {
  font-size: 13px;
  font-weight: 400;
  opacity: 0.88;
  margin-top: 2px;
}

/* ============ FAQ 区 ============ */
.faq { padding: 40px 20px 60px; }

.faq-card {
  background: #fff;
  border-radius: 10px;
  margin-bottom: 20px;
  box-shadow: 0 2px 10px rgba(63, 81, 181, 0.12);
  overflow: hidden;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  max-width: 1200px;
  margin-left: auto;
  margin-right: auto;
}
.faq-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(63, 81, 181, 0.18);
}

.question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 22px;
  background: var(--light-blue);
  border: none;
  cursor: pointer;
  font-size: 16px;
  font-weight: 700;
  color: #444;
  text-align: left;
  font-family: inherit;
  transition: background 0.2s;
}
.question:hover { background: #d5ecff; }

.q-icon {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--accent-blue);
  color: #fff;
  font-size: 16px;
  transition: transform 0.25s;
}
.faq-card.open .q-icon { transform: rotate(45deg); }

.answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
  color: #000;
  font-size: 15px;
}
.answer > * { padding: 0 22px; }
.answer p:last-child { padding-bottom: 20px; }
.answer p { color: #333; }
.answer ul { padding-bottom: 20px; }
.answer ul li {
  padding: 5px 0 5px 20px;
  position: relative;
  color: #333;
}
.answer ul li::before {
  content: "•";
  position: absolute;
  left: 4px;
  color: var(--accent-blue);
  font-weight: 700;
}

/* ============ 页脚 ============ */
.site-foot {
  background: var(--deep-blue);
  color: rgba(255, 255, 255, 0.8);
  padding: 30px 0;
}

.foot-inner { text-align: center; font-size: 14px; }
.foot-inner p { margin-bottom: 8px; }
.foot-links { line-height: 1.9; }

.site-foot a {
  color: #fff;
  transition: color 0.2s;
}
.site-foot a:hover { color: #9ecbff; }

/* ============ 响应式 ============ */
@media (max-width: 720px) {
  .nav-inner { flex-direction: column; align-items: flex-start; gap: 0; }
  .nav-links { padding-top: 0; padding-bottom: 14px; }
  .nav-slog { white-space: normal; border-left: none; margin-left: 0; padding-left: 0; }
  .hero-inner { flex-direction: column; gap: 30px; text-align: center; }
  .hero-pic { flex: 0 0 auto; }
  .pic-placeholder { width: 160px; height: 160px; font-size: 72px; }
}