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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    background: #f5f5f5;
    color: #333;
    overflow-x: hidden;
}

/* ========== 头部导航 ========== */
.header {
    background: #fff;
    box-shadow: 0 1px 4px rgba(0,0,0,0.08);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    height: 60px;
}

.header-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 30px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

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

.logo-icon {
    width: 36px;
    height: 36px;
    background: #4285f4;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 18px;
}

.logo-text {
    font-size: 20px;
    font-weight: 700;
    color: #333;
}

.nav {
    display: flex;
    align-items: center;
    gap: 30px;
}

.nav-link {
    text-decoration: none;
    color: #555;
    font-size: 15px;
    transition: color 0.2s;
}

.nav-link:hover {
    color: #4285f4;
}

/* ========== Hero 区域 ========== */
.hero {
    position: relative;
    background: linear-gradient(135deg, #e8f0fe 0%, #d4e4fc 50%, #c5d9f8 100%);
    padding: 140px 20px 80px;
    text-align: center;
    overflow: hidden;
    min-height: 480px;
}

/* 背景装饰图标 */
.bg-icon {
    position: absolute;
    color: rgba(66, 133, 244, 0.08);
    z-index: 0;
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: 1;
}

.hero-icon {
    width: 80px;
    height: 80px;
    background: #4285f4;
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 24px;
    color: #fff;
    font-size: 40px;
    box-shadow: 0 8px 24px rgba(66, 133, 244, 0.3);
}

.hero-title {
    font-size: 32px;
    font-weight: 700;
    color: #222;
    margin-bottom: 12px;
}

.hero-subtitle {
    font-size: 15px;
    color: #666;
    margin-bottom: 40px;
}

/* 下载按钮 */
.download-buttons {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.download-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 100px;
    height: 100px;
    background: #4285f4;
    border-radius: 50%;
    color: #fff;
    text-decoration: none;
    transition: all 0.3s;
    box-shadow: 0 4px 16px rgba(66, 133, 244, 0.3);
}

.download-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 24px rgba(66, 133, 244, 0.4);
    background: #3367d6;
}

.download-btn i {
    font-size: 28px;
    margin-bottom: 6px;
}

.download-btn span {
    font-size: 12px;
    font-weight: 500;
}

/* ========== 设备展示区域 ========== */
.devices {
    background: linear-gradient(180deg, #c5d9f8 0%, #b0c8f0 100%);
    padding: 0 20px 80px;
    overflow: hidden;
}

.devices-inner {
    max-width: 1100px;
    margin: 0 auto;
    display: flex;
    align-items: flex-start;
    justify-content: center;
    gap: 40px;
    position: relative;
}

/* ========== 笔记本电脑 ========== */
.laptop {
    width: 680px;
    flex-shrink: 0;
}

.laptop-screen {
    background: #1a1a2e;
    border-radius: 12px 12px 0 0;
    padding: 8px;
    border: 2px solid #555;
    border-bottom: none;
}

.chat-app {
    display: flex;
    background: #fff;
    border-radius: 6px;
    overflow: hidden;
    height: 380px;
}

/* 聊天侧边栏 */
.chat-sidebar {
    width: 220px;
    border-right: 1px solid #e8e8e8;
    display: flex;
    flex-direction: column;
}

.chat-sidebar-header {
    padding: 10px;
    border-bottom: 1px solid #eee;
}

.search-bar {
    background: #f2f2f2;
    border-radius: 6px;
    padding: 6px 10px;
    font-size: 12px;
    color: #999;
    display: flex;
    align-items: center;
    gap: 6px;
}

.chat-list {
    flex: 1;
    overflow-y: auto;
}

.chat-item {
    display: flex;
    align-items: center;
    padding: 10px;
    gap: 10px;
    cursor: pointer;
    transition: background 0.15s;
    border-bottom: 1px solid #f5f5f5;
}

.chat-item:hover {
    background: #f8f8f8;
}

.chat-item.active {
    background: #e8f0fe;
}

.avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    flex-shrink: 0;
}

.chat-item-info {
    flex: 1;
    min-width: 0;
}

.chat-item-name {
    font-size: 13px;
    font-weight: 500;
    color: #333;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.chat-item-msg {
    font-size: 11px;
    color: #999;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    margin-top: 2px;
}

.chat-item-time {
    font-size: 10px;
    color: #bbb;
    flex-shrink: 0;
}

/* 聊天主区域 */
.chat-main {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.chat-main-header {
    padding: 12px 16px;
    border-bottom: 1px solid #eee;
    display: flex;
    align-items: center;
    gap: 10px;
}

.chat-main-title {
    font-size: 14px;
    font-weight: 600;
    color: #333;
}

.chat-main-count {
    font-size: 12px;
    color: #999;
}

.chat-messages {
    flex: 1;
    padding: 16px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 12px;
    background: #f9f9f9;
}

.message {
    display: flex;
    gap: 8px;
    align-items: flex-start;
}

.message.sent {
    flex-direction: row-reverse;
}

.message-avatar {
    width: 30px;
    height: 30px;
    border-radius: 50%;
    flex-shrink: 0;
}

.message-content {
    max-width: 70%;
}

.message-name {
    font-size: 11px;
    color: #999;
    margin-bottom: 3px;
}

.message-bubble {
    background: #fff;
    padding: 8px 12px;
    border-radius: 8px;
    font-size: 12px;
    color: #333;
    line-height: 1.5;
    box-shadow: 0 1px 2px rgba(0,0,0,0.06);
}

.sent-bubble {
    background: #4285f4;
    color: #fff;
}

.chat-input {
    padding: 10px 16px;
    border-top: 1px solid #eee;
}

.chat-toolbar {
    display: flex;
    gap: 16px;
    color: #999;
    font-size: 16px;
}

.chat-toolbar i {
    cursor: pointer;
    transition: color 0.2s;
}

.chat-toolbar i:hover {
    color: #4285f4;
}

/* 笔记本底座 */
.laptop-base {
    background: linear-gradient(180deg, #c0c0c0, #a8a8a8);
    height: 18px;
    border-radius: 0 0 6px 6px;
    position: relative;
    margin: 0 -20px;
    border-top: 2px solid #999;
}

.laptop-notch {
    width: 120px;
    height: 6px;
    background: #b0b0b0;
    border-radius: 0 0 4px 4px;
    margin: 0 auto;
}

/* ========== 手机 ========== */
.phone {
    flex-shrink: 0;
    margin-top: 30px;
}

.phone-frame {
    width: 220px;
    background: #1a1a2e;
    border-radius: 28px;
    padding: 10px;
    border: 3px solid #555;
    position: relative;
}

.phone-notch {
    width: 80px;
    height: 6px;
    background: #333;
    border-radius: 3px;
    margin: 0 auto 8px;
}

.phone-screen {
    background: #fff;
    border-radius: 18px;
    overflow: hidden;
    height: 400px;
    display: flex;
    flex-direction: column;
}

.phone-header {
    background: #4285f4;
    color: #fff;
    padding: 14px 16px;
    font-size: 16px;
    font-weight: 600;
    text-align: center;
}

.phone-chat-list {
    flex: 1;
    overflow-y: auto;
}

.phone-chat-item {
    display: flex;
    align-items: center;
    padding: 12px 14px;
    gap: 10px;
    border-bottom: 1px solid #f0f0f0;
}

.phone-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    flex-shrink: 0;
}

.phone-chat-info {
    flex: 1;
    min-width: 0;
}

.phone-chat-name {
    font-size: 14px;
    font-weight: 500;
    color: #333;
}

.phone-chat-msg {
    font-size: 12px;
    color: #999;
    margin-top: 2px;
}

.phone-badge {
    width: 20px;
    height: 20px;
    background: #f44336;
    color: #fff;
    border-radius: 50%;
    font-size: 11px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.phone-bottom-nav {
    display: flex;
    border-top: 1px solid #eee;
    background: #fafafa;
}

.phone-nav-item {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 8px 0;
    font-size: 10px;
    color: #999;
    gap: 3px;
}

.phone-nav-item i {
    font-size: 16px;
}

.phone-nav-item.active {
    color: #4285f4;
}

/* ========== 页脚 ========== */
.footer {
    background: #2c2c3a;
    color: #aaa;
    text-align: center;
    padding: 24px 20px;
    font-size: 13px;
}

/* ========== 响应式 ========== */
@media (max-width: 900px) {
    .devices-inner {
        flex-direction: column;
        align-items: center;
    }

    .laptop {
        width: 100%;
        max-width: 600px;
    }

    .phone {
        margin-top: 40px;
    }

    .hero-title {
        font-size: 24px;
    }

    .download-buttons {
        gap: 14px;
    }

    .download-btn {
        width: 80px;
        height: 80px;
    }

    .download-btn i {
        font-size: 22px;
    }
}

@media (max-width: 600px) {
    .chat-sidebar {
        width: 160px;
    }

    .chat-app {
        height: 300px;
    }

    .laptop-base {
        margin: 0 -10px;
    }
}