/* Reset & Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --color-primary: #1a1a2e;
    --color-accent: #16213e;
    --color-highlight: #0f3460;
    --color-text: #333;
    --color-text-light: #666;
    --color-text-muted: #999;
    --color-bg: #fff;
    --color-border: #e8e8e8;
    --spacing-xs: 8px;
    --spacing-sm: 16px;
    --spacing-md: 24px;
    --spacing-lg: 48px;
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 8px 16px rgba(0, 0, 0, 0.1);
    --border-radius: 8px;
}

html, body {
    height: 100%;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-bg);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    transition: background-color var(--transition-normal);
    overflow-x: hidden;
}

/* 页面加载状态 */
body {
    opacity: 0;
    animation: fadeIn var(--transition-slow) forwards;
}

body.page-loaded {
    opacity: 1;
}

/* 动画定义 */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes slideInUp {
    from {
        transform: translateY(30px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

@keyframes scaleIn {
    from {
        transform: scale(0.95);
        opacity: 0;
    }
    to {
        transform: scale(1);
        opacity: 1;
    }
}

@keyframes pulse {
    0% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
    100% {
        transform: scale(1);
    }
}

/* 元素进入视口动画 */
.header, .main-content, .footer {
    opacity: 0;
    transform: translateY(20px);
    transition: all var(--transition-slow);
}

.header.animate-in, .main-content.animate-in, .footer.animate-in {
    opacity: 1;
    transform: translateY(0);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Header */
.header {
    padding: var(--spacing-md) 0;
    border-bottom: 1px solid var(--color-border);
    background-color: var(--color-bg);
    flex-shrink: 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-xs);
}

.logo-img {
    width: 48px;
    height: 48px;
    object-fit: contain;
}

.logo-text h1 {
    font-size: 18px;
    font-weight: 600;
    color: var(--color-primary);
    line-height: 1.3;
}

.logo-en {
    font-size: 12px;
    color: var(--color-text-muted);
    letter-spacing: 0.02em;
}

/* Main Content */
.main-content {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-lg) var(--spacing-md);
}

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

.slogan {
    font-size: 48px;
    font-weight: 700;
    color: var(--color-primary);
    line-height: 1.2;
    margin-bottom: var(--spacing-xs);
    letter-spacing: 0.02em;
    position: relative;
    display: block;
}

.slogan-en {
    font-size: 20px;
    color: var(--color-highlight);
    font-weight: 400;
    letter-spacing: 0.05em;
    display: block;
}

/* Footer */
.footer {
    background-color: var(--color-primary);
    color: #fff;
    padding: var(--spacing-lg) 0;
    flex-shrink: 0;
}

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

.copyright {
    font-size: 14px;
    margin-bottom: var(--spacing-xs);
    opacity: 0.9;
}

.beian {
    font-size: 12px;
    opacity: 0.7;
}

.beian a {
    color: #fff;
    text-decoration: none;
    transition: all var(--transition-fast);
    position: relative;
}

.beian a:hover {
    text-decoration: underline;
    color: rgba(255, 255, 255, 0.8);
    transform: translateY(-1px);
}

.beian a::after {
    content: '';
    position: absolute;
    width: 100%;
    height: 1px;
    bottom: -2px;
    left: 0;
    background-color: rgba(255, 255, 255, 0.5);
    transform: scaleX(0);
    transform-origin: bottom right;
    transition: transform var(--transition-fast);
}

.beian a:hover::after {
    transform: scaleX(1);
    transform-origin: bottom left;
}

/* Responsive */
@media (max-width: 768px) {
    .slogan {
        font-size: 32px;
    }

    .slogan-en {
        font-size: 16px;
    }

    .logo-text h1 {
        font-size: 16px;
    }

    .logo-en {
        display: none;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-sm);
    }

    .slogan {
        font-size: 24px;
    }

    .slogan-en {
        font-size: 14px;
    }

    .logo-img {
        width: 40px;
        height: 40px;
    }

    .main-content {
        padding: var(--spacing-md);
    }
}