/* ========================================
   Mr.Xia 个人网站 - 统一样式表
   简约现代风格，渐变动效与微交互
   ======================================== */

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

/* ===== CSS 变量定义 ===== */
:root {
    /* 主题色彩 */
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary-color: #ec4899;
    --accent-color: #f59e0b;
    
    /* 中性色 */
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-dark: #111827;
    
    /* 间距 */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    
    /* 阴影 */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px -5px rgba(0, 0, 0, 0.15);
    --shadow-xl: 0 20px 40px -10px rgba(0, 0, 0, 0.2);
    
    /* 圆角 */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* 过渡 */
    --transition-fast: 150ms ease-in-out;
    --transition-base: 300ms ease-in-out;
    --transition-slow: 500ms ease-in-out;
}

/* ===== 全局样式 ===== */
html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Microsoft YaHei', 'PingFang SC', sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-secondary);
    min-height: 100vh;
    position: relative;
    overflow-x: hidden;
}

/* ===== 动态背景效果（亮点1：渐变动画背景） ===== */
.bg-img {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 25%, #f093fb 50%, #4facfe 75%, #00f2fe 100%);
    background-size: 400% 400%;
    animation: gradientShift 15s ease infinite;
    opacity: 0.05;
}

@keyframes gradientShift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

/* ===== 页眉导航（亮点2：毛玻璃效果） ===== */
header {
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    background: rgba(255, 255, 255, 0.8);
    border-bottom: 1px solid rgba(0, 0, 0, 0.08);
    padding: var(--spacing-md) var(--spacing-lg);
    box-shadow: var(--shadow-sm);
}

header nav {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.5px;
}

.nav-links {
    display: flex;
    gap: var(--spacing-md);
    list-style: none;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-md);
    transition: all var(--transition-base);
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transform: translateX(-50%);
    transition: width var(--transition-base);
}

.nav-links a:hover {
    color: var(--primary-color);
    background: rgba(99, 102, 241, 0.05);
}

.nav-links a:hover::after {
    width: 80%;
}

/* ===== 主内容区域 ===== */
main {
    max-width: 1200px;
    margin: var(--spacing-xl) auto;
    padding: 0 var(--spacing-lg);
    min-height: calc(100vh - 200px);
}

/* ===== 标题样式 ===== */
h1, h2, h3 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
}

h1 {
    font-size: 2.5rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: var(--spacing-lg);
}

h2 {
    font-size: 1.875rem;
    color: var(--text-primary);
}

h3 {
    font-size: 1.5rem;
    color: var(--text-secondary);
}

/* ===== 段落与文本 ===== */
p {
    margin-bottom: var(--spacing-sm);
    color: var(--text-secondary);
}

a {
    text-decoration: none;
    color: var(--primary-color);
    transition: color var(--transition-fast);
}

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

/* ===== 卡片组件（亮点3：悬浮动效） ===== */
.card {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-base);
    border: 1px solid rgba(0, 0, 0, 0.05);
}

.card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: rgba(99, 102, 241, 0.2);
}

/* ===== 阴影盒子样式 ===== */
.shadowbox {
    background: linear-gradient(135deg, #ffffff 0%, #f8fafc 100%);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    margin: var(--spacing-lg) 0;
    box-shadow: var(--shadow-lg);
    border: 1px solid rgba(99, 102, 241, 0.1);
    position: relative;
    overflow: hidden;
}

.shadowbox::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color), var(--accent-color));
    background-size: 200% 100%;
    animation: shimmer 3s linear infinite;
}

@keyframes shimmer {
    0% { background-position: -200% 0; }
    100% { background-position: 200% 0; }
}

/* ===== 按钮样式（亮点4：微交互按钮） ===== */
.btn {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-lg);
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
    border: none;
    border-radius: var(--radius-lg);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-md);
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn:hover::before {
    width: 300px;
    height: 300px;
}

.btn:active {
    transform: translateY(0);
}

.btn-secondary {
    background: linear-gradient(135deg, var(--text-secondary), var(--text-primary));
}

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

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

/* ===== 时间显示器 ===== */
#currentTime {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.1), rgba(236, 72, 153, 0.1));
    border-radius: var(--radius-lg);
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--primary-color);
    box-shadow: var(--shadow-sm);
    margin: var(--spacing-md) 0;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.02); }
}

/* ===== 计时器样式 ===== */
.timer-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-lg);
    padding: var(--spacing-xl);
}

#timer {
    font-size: 4rem;
    font-weight: 700;
    font-family: 'Courier New', monospace;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: 0.1em;
}

.timer-controls {
    display: flex;
    gap: var(--spacing-sm);
}

/* ===== 文本工具类 ===== */
.indent {
    text-indent: 2em;
}

.negative-indent {
    text-indent: -2em;
}

.text-center {
    text-align: center;
}

.text-small {
    font-size: 0.875rem;
    color: var(--text-light);
}

/* ===== 404页面样式 ===== */
.error-page {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 80vh;
    text-align: center;
    gap: var(--spacing-md);
}

.error-code {
    font-size: 8rem;
    font-weight: 900;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1;
}

/* ===== 响应式设计 ===== */
@media (max-width: 768px) {
    html {
        font-size: 14px;
    }
    
    header nav {
        flex-direction: column;
        gap: var(--spacing-sm);
    }
    
    .nav-links {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    #timer {
        font-size: 2.5rem;
    }
    
    .error-code {
        font-size: 5rem;
    }
}

@media (max-width: 480px) {
    main {
        padding: 0 var(--spacing-sm);
    }
    
    .card, .shadowbox {
        padding: var(--spacing-md);
    }
}

/* ===== 加载动画（亮点5：页面进入动画） ===== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

/* 为不同元素添加延迟 */
.fade-in-up:nth-child(1) { animation-delay: 0.1s; }
.fade-in-up:nth-child(2) { animation-delay: 0.2s; }
.fade-in-up:nth-child(3) { animation-delay: 0.3s; }
.fade-in-up:nth-child(4) { animation-delay: 0.4s; }
.fade-in-up:nth-child(5) { animation-delay: 0.5s; }

/* ===== 滚动条美化 ===== */
::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: var(--radius-md);
}

::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(135deg, var(--primary-dark), var(--secondary-color));
}