/* ============================================
   李凯个人主页 - 全局美化样式
   主题：大气科学 · 深蓝天穹
   ============================================ */

/* ---------- CSS 变量 ---------- */
:root {
    /* 主色调 - 天空与海洋的深邃 */
    --primary: #1e3a5f;
    --primary-light: #2c5282;
    --primary-dark: #152a45;
    
    /* 强调色 - 晴空与云 */
    --accent: #38bdf8;
    --accent-light: #7dd3fc;
    --accent-dark: #0ea5e9;
    
    /* 辅助色 - 日落金 */
    --gold: #f59e0b;
    --gold-light: #fbbf24;
    
    /* 背景色 */
    --bg-primary: #f0f4f8;
    --bg-secondary: #ffffff;
    --bg-tertiary: #e8eef5;
    
    /* 文字色 */
    --text-primary: #1e293b;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    
    /* 边框与阴影 */
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 3px rgba(30, 58, 95, 0.08);
    --shadow-md: 0 4px 12px rgba(30, 58, 95, 0.1);
    --shadow-lg: 0 10px 30px rgba(30, 58, 95, 0.12);
    --shadow-xl: 0 20px 50px rgba(30, 58, 95, 0.15);
    
    /* 渐变 */
    --gradient-primary: linear-gradient(135deg, #1e3a5f 0%, #2c5282 50%, #38bdf8 100%);
    --gradient-sky: linear-gradient(180deg, #e0f2fe 0%, #f0f9ff 50%, #ffffff 100%);
    --gradient-card: linear-gradient(135deg, #ffffff 0%, #f8fafc 100%);
    --gradient-accent: linear-gradient(135deg, #38bdf8 0%, #0ea5e9 100%);
    
    /* 圆角 */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    
    /* 过渡 */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* ---------- 基础重置 ---------- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    min-height: 100vh;
    position: relative;
}

/* ---------- 背景装饰 - 云纹效果 ---------- */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: 
        radial-gradient(ellipse 80% 50% at 50% -20%, rgba(56, 189, 248, 0.08), transparent),
        radial-gradient(ellipse 60% 40% at 80% 80%, rgba(245, 158, 11, 0.05), transparent),
        radial-gradient(ellipse 50% 30% at 10% 60%, rgba(30, 58, 95, 0.05), transparent);
    pointer-events: none;
    z-index: 0;
}

/* ---------- 通用容器 ---------- */
.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 60px 24px;
    position: relative;
    z-index: 1;
}

/* ---------- 返回按钮 ---------- */
.back-home {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--primary-light);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    padding: 10px 20px;
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: all var(--transition-normal);
    margin-bottom: 32px;
}

.back-home:hover {
    background: var(--bg-secondary);
    border-color: var(--accent);
    color: var(--accent-dark);
    transform: translateX(-4px);
    box-shadow: var(--shadow-md);
}

.back-home i {
    transition: transform var(--transition-fast);
}

.back-home:hover i {
    transform: translateX(-2px);
}

/* ---------- 卡片通用样式 ---------- */
.card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
}

.card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
    border-color: rgba(56, 189, 248, 0.3);
}

/* ---------- 标题通用样式 ---------- */
.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 24px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.section-title::before {
    content: '';
    width: 4px;
    height: 28px;
    background: var(--gradient-accent);
    border-radius: 2px;
}

/* ---------- 标签/徽章 ---------- */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 4px 12px;
    font-size: 0.8rem;
    font-weight: 500;
    border-radius: 20px;
    line-height: 1.5;
}

.badge-primary {
    background: rgba(56, 189, 248, 0.12);
    color: var(--accent-dark);
    border: 1px solid rgba(56, 189, 248, 0.3);
}

.badge-gold {
    background: rgba(245, 158, 11, 0.12);
    color: #d97706;
    border: 1px solid rgba(245, 158, 11, 0.3);
}

.badge-green {
    background: rgba(34, 197, 94, 0.12);
    color: #16a34a;
    border: 1px solid rgba(34, 197, 94, 0.3);
}

.badge-purple {
    background: rgba(139, 92, 246, 0.12);
    color: #7c3aed;
    border: 1px solid rgba(139, 92, 246, 0.3);
}

/* ---------- 动画 ---------- */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}

@keyframes pulse-glow {
    0%, 100% { box-shadow: 0 0 20px rgba(56, 189, 248, 0.2); }
    50% { box-shadow: 0 0 35px rgba(56, 189, 248, 0.4); }
}

.animate-fade-in-up {
    animation: fadeInUp 0.6s ease forwards;
}

.animate-fade-in {
    animation: fadeIn 0.8s ease forwards;
}

.animate-float {
    animation: float 3s ease-in-out infinite;
}

/* ---------- 响应式 ---------- */
@media (max-width: 768px) {
    .container {
        padding: 40px 16px;
    }
    
    .section-title {
        font-size: 1.25rem;
    }
    
    .section-title::before {
        height: 24px;
    }
}