:root {
    --bg-color: #0d0e12;
    --card-bg: #1a1c23;
    --text-main: #ffffff;
    --text-muted: #a0a0a0;
    
    --color-cyan: #00f2ff;
    --color-cyan-glow: rgba(0, 242, 255, 0.4);
    
    --color-purple: #bd00ff;
    --color-purple-glow: rgba(189, 0, 255, 0.4);
    
    --color-green: #00ff9d;
    --color-green-glow: rgba(0, 255, 157, 0.4);

    --font-main: 'Inter', 'Noto Sans JP', sans-serif;
    --transition-speed: 0.3s;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    font-family: var(--font-main);
    line-height: 1.6;
    overflow-x: hidden;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    width: 100%;
}

/* Background Effect */
.background-glow {
    position: fixed;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at center, rgba(30, 35, 50, 0.3) 0%, transparent 70%);
    z-index: -1;
    pointer-events: none;
}

/* Header */
.site-header {
    padding: 4rem 0 2rem;
    text-align: center;
}

.site-header h1 {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, #fff 0%, #a5b4fc 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.05em;
}

.subtitle {
    color: var(--text-muted);
    font-size: 1.2rem;
}

/* Main Content */
main {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem 0 4rem;
}

.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    width: 100%;
}

/* Cards */
.card {
    position: relative;
    background-color: var(--card-bg);
    border-radius: 16px;
    padding: 2rem;
    text-decoration: none;
    color: var(--text-main);
    overflow: hidden;
    transition: transform var(--transition-speed) ease, box-shadow var(--transition-speed) ease;
    border: 1px solid rgba(255, 255, 255, 0.05);
    display: flex;
    flex-direction: column;
    height: 100%;
}

.card:hover {
    transform: translateY(-5px);
}

.card-content {
    position: relative;
    z-index: 2;
    display: flex;
    flex-direction: column;
    height: 100%;
}

.card-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.card h2 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.card p {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 2rem;
    flex-grow: 1;
}

.btn-link {
    display: inline-block;
    font-weight: 600;
    transition: transform var(--transition-speed) ease;
}

.card:hover .btn-link {
    transform: translateX(5px);
}

/* Card Specific Glows */
.card-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(800px circle at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(255,255,255,0.06), transparent 40%);
    opacity: 0;
    transition: opacity 0.5s;
    z-index: 1;
}

.card:hover .card-bg {
    opacity: 1;
}

.card-cyan:hover {
    box-shadow: 0 0 30px var(--color-cyan-glow);
    border-color: var(--color-cyan);
}
.card-cyan .btn-link { color: var(--color-cyan); }

.card-purple:hover {
    box-shadow: 0 0 30px var(--color-purple-glow);
    border-color: var(--color-purple);
}
.card-purple .btn-link { color: var(--color-purple); }

.card-green:hover {
    box-shadow: 0 0 30px var(--color-green-glow);
    border-color: var(--color-green);
}
.card-green .btn-link { color: var(--color-green); }

/* Footer */
.site-footer {
    text-align: center;
    padding: 2rem 0;
    color: var(--text-muted);
    font-size: 0.9rem;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

@media (max-width: 768px) {
    .site-header h1 {
        font-size: 2.5rem;
    }
    .card-grid {
        grid-template-columns: 1fr;
    }
}