:root {
    --bg-color: #1a1a1a;
    --text-color: #ffffff;
    --card-bg: #2d2d2d;
    --accent: #4a90e2;
}

body {
    margin: 0;
    padding: 0;
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    min-height: 100vh;
}

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

header {
    text-align: center;
    margin-bottom: 4rem;
}

h1 {
    font-size: 3rem;
    margin-bottom: 0.5rem;
    background: linear-gradient(45deg, #4a90e2, #9b59b6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    padding: 1rem;
}

.card {
    background-color: var(--card-bg);
    border-radius: 12px;
    text-decoration: none;
    color: inherit;
    transition: transform 0.2s, box-shadow 0.2s;
    overflow: hidden;
    border: 1px solid #3d3d3d;
    display: block;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.3);
    border-color: var(--accent);
}

.card-content {
    padding: 2rem;
    text-align: center;
}

h2 {
    margin-top: 0;
    color: var(--accent);
}

footer {
    text-align: center;
    margin-top: 4rem;
    color: #666;
}

/* Button style for sub-pages */
.home-button {
    position: absolute;
    top: 20px;
    left: 20px;
    z-index: 1000;
    background: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 10px 20px;
    text-decoration: none;
    border-radius: 20px;
    font-family: sans-serif;
    backdrop-filter: blur(5px);
    transition: background 0.3s;
}

.home-button:hover {
    background: rgba(0, 0, 0, 0.9);
}