/* 谷歌浏览器官方配色 + 必应SEO优化样式 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
}

:root {
  --google-blue: #4285F4;
  --google-red: #EA4335;
  --google-yellow: #FBBC05;
  --google-green: #34A853;
  --text-dark: #202124;
  --text-light: #5f6368;
  --bg-white: #ffffff;
  --bg-gray: #f8f9fa;
  --border-color: #dadce0;
  --shadow: 0 1px 3px rgba(0,0,0,0.12);
}

body {
  color: var(--text-dark);
  background: var(--bg-white);
  line-height: 1.6;
  overflow-x: hidden;
}

/* 头部导航 */
header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 5%;
  position: sticky;
  top: 0;
  background: var(--bg-white);
  box-shadow: var(--shadow);
  z-index: 999;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
}

.logo img {
  width: 40px;
  height: 40px;
}

.logo span {
  font-size: 22px;
  font-weight: 500;
  color: var(--text-dark);
}

nav ul {
  display: flex;
  list-style: none;
  gap: 30px;
}

nav a {
  text-decoration: none;
  color: var(--text-dark);
  font-size: 15px;
  font-weight: 500;
  transition: color 0.2s;
}

nav a:hover, nav a.active {
  color: var(--google-blue);
}

/* 核心下载按钮（醒目样式） */
.download-btn {
  background: var(--google-blue);
  color: white !important;
  padding: 10px 24px;
  border-radius: 4px;
  border: none;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
  display: inline-block;
  box-shadow: 0 2px 4px rgba(66,133,244,0.3);
}

.download-btn:hover {
  background: #3367D6;
  transform: translateY(-1px);
  box-shadow: 0 3px 6px rgba(66,133,244,0.4);
}

/* 主容器 */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 5%;
}

/* 首页banner */
.banner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 40px;
  margin-bottom: 60px;
}

.banner-text {
  flex: 1;
  min-width: 300px;
}

.banner-text h1 {
  font-size: 48px;
  line-height: 1.2;
  margin-bottom: 20px;
  color: var(--text-dark);
}

.banner-text p {
  font-size: 18px;
  color: var(--text-light);
  margin-bottom: 30px;
  max-width: 500px;
}

.banner-img {
  flex: 1;
  min-width: 300px;
  text-align: center;
}

.banner-img img {
  max-width: 100%;
  height: auto;
}

/* 功能模块 */
.section-title {
  text-align: center;
  font-size: 32px;
  margin-bottom: 40px;
  color: var(--text-dark);
}

.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 30px;
  margin-bottom: 60px;
}

.feature-card {
  background: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 30px;
  text-align: center;
  transition: transform 0.2s;
}

.feature-card:hover {
  transform: translateY(-5px);
}

.feature-card img {
  width: 64px;
  height: 64px;
  margin-bottom: 20px;
}

.feature-card h3 {
  font-size: 20px;
  margin-bottom: 15px;
  color: var(--text-dark);
}

.feature-card p {
  color: var(--text-light);
  font-size: 15px;
}

/* 页脚 */
footer {
  background: var(--bg-gray);
  padding: 40px 5%;
  border-top: 1px solid var(--border-color);
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 30px;
}

.footer-links {
  display: flex;
  gap: 40px;
}

.footer-links ul {
  list-style: none;
}

.footer-links h4 {
  font-size: 16px;
  margin-bottom: 15px;
  color: var(--text-dark);
}

.footer-links a {
  text-decoration: none;
  color: var(--text-light);
  font-size: 14px;
  line-height: 2;
}

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

.copyright {
  text-align: center;
  margin-top: 30px;
  color: var(--text-light);
  font-size: 13px;
}

/* 页面通用样式 */
.page-content {
  padding: 60px 0;
}

.page-content h2 {
  font-size: 36px;
  margin-bottom: 25px;
  color: var(--text-dark);
}

.page-content p {
  font-size: 16px;
  color: var(--text-light);
  margin-bottom: 20px;
  line-height: 1.8;
}

/* 响应式 */
@media (max-width: 768px) {
  .banner-text h1 {
    font-size: 36px;
  }
  nav ul {
    gap: 15px;
  }
  .footer-links {
    flex-direction: column;
    gap: 20px;
  }
}