/* ==========================================================================
   1. 全局变量与基础复位
   ========================================================================== */
:root {
    /* 品牌核心色 */
    --primary: #007AFF;
    --primary-hover: #0063CC;
    --primary-light: #e3f2fd;
    
    /* 文字颜色 */
    --text-main: #1d1d1f;
    --text-sub: #666666;
    --text-light: #999999;
    
    /* 背景与边框 */
    --bg-light: #f5f5f7;
    --bg-white: #ffffff;
    --border-color: #eeeeee;
    
    /* 阴影 */
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.05);
    --shadow-md: 0 10px 30px rgba(0,0,0,0.1);
    --shadow-lg: 0 20px 50px rgba(0,122,255,0.15);
}

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

body {
    font-family: "PingFang SC", "SF Pro Display", "Microsoft YaHei", sans-serif;
    color: var(--text-main);
    background-color: var(--bg-white);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

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

a {
    text-decoration: none;
    color: inherit;
    transition: 0.3s ease;
}

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

/* ==========================================================================
   2. 公用组件 (按钮、标题、导航)
   ========================================================================== */
.navbar {
    height: 70px;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(15px);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
    display: flex;
    align-items: center;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
}

.logo {
    display: flex;
    align-items: center;
    font-size: 22px;
    font-weight: bold;
    color: var(--primary);
}

.logo img {
    height: 38px;
    margin-right: 12px;
}

.nav-links {
    display: flex;
    list-style: none;
}

.nav-links li {
    margin-left: 35px;
}

.nav-links a {
    font-size: 15px;
    color: var(--text-sub);
    font-weight: 500;
}

.nav-links a:hover, .nav-links a.active {
    color: var(--primary);
}

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 14px 45px;
    border-radius: 30px;
    font-weight: 600;
    cursor: pointer;
    text-align: center;
}

.btn-primary {
    background: var(--primary);
    color: #fff;
    box-shadow: 0 8px 20px rgba(0, 122, 255, 0.25);
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(0, 122, 255, 0.35);
}

/* ==========================================================================
   3. 首页特定样式 (Hero, AI, Matrix)
   ========================================================================== */
/* 英雄首屏 */
.hero-center {
    padding: 100px 0 60px;
    text-align: center;
    background: linear-gradient(180deg, #ffffff 0%, #f0f7ff 100%);
}

.hero-center h1 {
    font-size: 52px;
    margin-bottom: 25px;
    letter-spacing: -1px;
}

.v-tag {
    display: block;
    margin-top: 15px;
    font-size: 13px;
    color: var(--text-light);
}

.mockup-container {
    margin-top: 60px;
    perspective: 1000px;
}

.main-mockup {
    max-width: 900px;
    border-radius: 12px;
    box-shadow: var(--shadow-lg);
}

/* AI 展示区 */
.ai-section {
    padding: 90px 0;
    background: #fff;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.ai-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 25px;
}

.ai-card {
    text-align: center;
    padding: 40px 25px;
    border: 1px solid var(--border-color);
    border-radius: 16px;
}

.ai-card:hover {
    border-color: var(--primary);
    background: #fafdff;
    transform: translateY(-5px);
}

.ai-card img {
    height: 50px;
    margin-bottom: 20px;
}

/* 功能矩阵 (参考图2风格) */
.feature-matrix {
    padding: 100px 0;
    background: var(--bg-light);
}

.matrix-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 60px 40px;
}

.m-item {
    display: flex;
    align-items: flex-start;
}

.m-icon {
    width: 52px;
    height: 52px;
    margin-right: 20px;
    flex-shrink: 0;
}

.m-info h3 {
    font-size: 19px;
    margin-bottom: 10px;
}

.m-info p {
    font-size: 14px;
    color: var(--text-sub);
    line-height: 1.7;
}

/* ==========================================================================
   4. 通用子页面 (下载、日志、关于)
   ========================================================================== */
/* 通用页头 */
.page-header {
    padding: 80px 0;
    text-align: center;
    background: var(--bg-light);
}

/* 下载卡片布局 */
.download-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin: 60px 0;
}

.download-card {
    padding: 50px 30px;
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 20px;
    text-align: center;
}

.download-card:hover {
    box-shadow: var(--shadow-md);
    border-color: var(--primary);
}

/* 更新日志时间轴 */
.content-section { padding: 80px 0; }

.log-item {
    margin-bottom: 50px;
    padding-left: 25px;
    border-left: 3px solid var(--primary-light);
    position: relative;
    transition: 0.3s;
}

.log-item:hover { border-left-color: var(--primary); }

.log-badge {
    display: inline-block;
    padding: 4px 12px;
    background: var(--primary-light);
    color: var(--primary);
    border-radius: 6px;
    font-size: 12px;
    font-weight: bold;
    margin-bottom: 12px;
}

.log-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

/* ==========================================================================
   5. 页脚
   ========================================================================== */
footer {
    background: #1d1d1f;
    color: #86868b;
    padding: 60px 0;
    text-align: center;
    font-size: 14px;
}

footer p {
    margin-bottom: 10px;
}

footer .icp {
    font-size: 12px;
    opacity: 0.5;
}

/* ==========================================================================
   6. 响应式适配
   ========================================================================== */
@media (max-width: 992px) {
    .matrix-grid { grid-template-columns: repeat(2, 1fr); }
    .hero-center h1 { font-size: 38px; }
}

@media (max-width: 768px) {
    .nav-links { display: none; } /* 移动端建议折叠菜单 */
    .matrix-grid, .ai-grid { grid-template-columns: 1fr; }
    .hero-center { padding: 60px 0; }
}