/**
 * ================================================================
 *  base.css — 全局基础样式（极简现代风格）
 * ================================================================
 */

/* ==== 1. 设计 Token（CSS 自定义属性）==== */
:root {
    /* 主色 - 喜云生态绿 */
    --primary: #008800;
    --primary-dark: #006600;
    --primary-light: #e6f5e6;
    
    /* 点缀色 - 暖云橙 */
    --accent: #FF9955;
    --accent-dark: #E68A3D;
    --accent-light: #FFF3E8;
    
    /* 文字色 */
    --text-primary: #1a1a1a;
    --text-secondary: #666666;
    --text-muted: #999999;
    
    /* 背景色 */
    --bg-white: #ffffff;
    --bg-light: #f8f9fa;
    --bg-dark: #1a1a1a;
    
    /* 边框和阴影 */
    --border: #e5e5e5;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 32px rgba(0,0,0,0.1);
    
    /* 圆角 */
    --radius: 16px;
    --radius-sm: 8px;
}

/* ==== 2. Reset — 浏览器默认样式重置 ==== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, "PingFang SC", "Noto Sans SC", "Helvetica Neue", Arial, sans-serif;
    color: var(--text-primary);
    background-color: var(--bg-white);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: var(--primary);
    text-decoration: none;
    transition: color 0.2s ease;
}

a:hover {
    color: var(--primary-dark);
}

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

/* ==== 3. 排版基础 ==== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    color: var(--text-primary);
}

h1 { font-size: 48px; letter-spacing: -0.02em; }
h2 { font-size: 36px; letter-spacing: -0.02em; }
h3 { font-size: 24px; }
h4 { font-size: 20px; }

p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ==== 4. 通用工具类 ==== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* 按钮基类 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 32px;
    border-radius: 12px;
    font-weight: 500;
    font-size: 16px;
    text-decoration: none;
    transition: all 0.2s ease;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: var(--primary);
    color: white;
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(0, 136, 0, 0.3);
    color: white;
}

.btn-outline {
    background: transparent;
    color: var(--primary);
    border: 2px solid var(--primary);
}

.btn-outline:hover {
    background: var(--primary);
    color: white;
}

/* 橙色点缀按钮 */
.btn-accent {
    background: var(--accent);
    color: white;
}

.btn-accent:hover {
    background: var(--accent-dark);
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(255, 153, 85, 0.3);
    color: white;
}

/* 区块通用样式 */
section {
    padding: 80px 0;
}

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

.section-header h2 {
    margin-bottom: 16px;
}

.section-header p {
    font-size: 18px;
    max-width: 600px;
    margin: 0 auto;
}

/* ==== 5. 响应式字体大小 ==== */
@media (max-width: 768px) {
    h1 { font-size: 32px; }
    h2 { font-size: 28px; }
    h3 { font-size: 20px; }
    h4 { font-size: 18px; }

    .container {
        padding: 0 16px;
    }

    section {
        padding: 60px 0;
    }

    .section-header {
        margin-bottom: 40px;
    }
}

@media (max-width: 480px) {
    h1 { font-size: 28px; }
    h2 { font-size: 24px; }

    .btn {
        width: 100%;
    }
}