:root {
    --primary-color: #0d47a1;
    --secondary-color: #ffffff;
    --accent-color: #ff9800;
    --dark-bg: #121a2b;
    --light-bg: #1e2a4a;
    --text-color: #e0e0e0;
    --highlight: #4fc3f7;
}

body {
    font-family: 'Roboto', sans-serif;
    background: linear-gradient(135deg, var(--dark-bg), var(--light-bg));
    color: var(--text-color);
    margin: 0;
    padding: 0;
    line-height: 1.6;
}

header {
    background: rgba(13, 71, 161, 0.8);
    padding: 2rem;
    text-align: center;
    border-bottom: 3px solid var(--accent-color);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    position: relative;
    overflow: hidden;
}

header::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('https://images.gptkong.com/demo/sample1.png') center/cover;
    opacity: 0.1;
    z-index: -1;
}

h1, h2, h3, h4 {
    color: var(--highlight);
    margin-top: 0;
    font-weight: 500;
}

h1 {
    font-size: 2.5rem;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

h2 {
    font-size: 1.8rem;
    border-left: 4px solid var(--accent-color);
    padding-left: 1rem;
    margin: 2rem 0 1rem;
}

h3 {
    font-size: 1.5rem;
    margin: 1.5rem 0 0.8rem;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

.article-container {
    background: rgba(30, 42, 74, 0.7);
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(10px);
    margin-bottom: 3rem;
}

.note {
    background: rgba(255, 152, 0, 0.1);
    border-left: 4px solid var(--accent-color);
    padding: 1rem;
    margin: 1.5rem 0;
    border-radius: 0 4px 4px 0;
}

.code-container {
    background: #1e1e1e;
    border-radius: 8px;
    padding: 1.5rem;
    margin: 1.5rem 0;
    overflow: auto;
    box-shadow: inset 0 0 10px rgba(0, 0, 0, 0.5);
}

pre {
    margin: 0;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
    line-height: 1.5;
    color: #d4d4d4;
}

code {
    background: rgba(255, 255, 255, 0.1);
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
}

.image-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.image-card {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 8px;
    overflow: hidden;
    transition: transform 0.3s, box-shadow 0.3s;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.image-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.3);
}

.image-card img {
    width: 100%;
    height: auto;
    display: block;
    border-radius: 8px 8px 0 0;
}

.image-caption {
    padding: 1rem;
    background: rgba(0, 0, 0, 0.3);
}

.footer {
    text-align: center;
    padding: 2rem;
    background: rgba(13, 71, 161, 0.2);
    margin-top: 3rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }
    
    .article-container {
        padding: 1.5rem;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    h2 {
        font-size: 1.5rem;
    }
    
    .image-grid {
        grid-template-columns: 1fr;
    }
}

/* Animations */
@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

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

/* Tab styles */
.tabs {
    display: flex;
    margin: 2rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
}

.tab {
    padding: 0.8rem 1.5rem;
    cursor: pointer;
    position: relative;
    color: var(--text-color);
    opacity: 0.7;
    transition: all 0.3s;
}

.tab:hover {
    opacity: 1;
}

.tab.active {
    opacity: 1;
    color: var(--highlight);
}

.tab.active::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--highlight);
}

.tab-content {
    display: none;
    padding: 1.5rem;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 0 0 8px 8px;
}

.tab-content.active {
    display: block;
}

/* Card styles */
.card {
    background: rgba(30, 42, 74, 0.5);
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s, box-shadow 0.3s;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.3);
    border-color: rgba(79, 195, 247, 0.3);
}

.card-title {
    color: var(--highlight);
    margin-top: 0;
    font-size: 1.2rem;
}

/* Notification */
.notification {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: rgba(255, 152, 0, 0.9);
    color: white;
    padding: 1rem 1.5rem;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
    z-index: 1000;
    animation: slideIn 0.5s ease-out;
}

@keyframes slideIn {
    from { transform: translateX(100%); }
    to { transform: translateX(0); }
}