:root {
    --primary-color: #6366f1; /* Indigo */
    --primary-color-hover: #4f46e5;
    --bg-color: #0f172a; /* Slate 900 */
    --text-main: #f8fafc; /* Slate 50 */
    --text-muted: #94a3b8; /* Slate 400 */
    --card-bg: rgba(30, 41, 59, 0.7); /* Slate 800 with opacity */
    --card-border: rgba(255, 255, 255, 0.1);
    --glass-shadow: 0 4px 30px rgba(0, 0, 0, 0.1);
}

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

body {
    font-family: 'Inter', 'Noto Sans JP', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    position: relative;
    overflow-x: hidden;
}

/* Background Animation Placeholder */
.background-animation {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    background: radial-gradient(circle at 15% 50%, rgba(99, 102, 241, 0.15), transparent 25%),
                radial-gradient(circle at 85% 30%, rgba(236, 72, 153, 0.15), transparent 25%);
    animation: bgPulse 15s ease-in-out infinite alternate;
}

@keyframes bgPulse {
    0% { transform: scale(1); }
    100% { transform: scale(1.1); }
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 2rem;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}

.header {
    text-align: center;
    margin-bottom: 4rem;
    margin-top: 2rem;
    animation: fadeInDown 0.8s ease-out;
}

.logo {
    font-size: 3rem;
    font-weight: 800;
    letter-spacing: -1px;
    background: linear-gradient(135deg, #818cf8 0%, #e879f9 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 0.5rem;
}

.subtitle {
    color: var(--text-muted);
    font-size: 1.1rem;
}

.main-content {
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
    animation: fadeInUp 0.8s ease-out 0.2s both;
}

.intro {
    text-align: center;
    margin-bottom: 3rem;
    max-width: 600px;
}

.intro h2 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.intro p {
    color: var(--text-muted);
    font-size: 1.1rem;
}

.contents-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    width: 100%;
    max-width: 800px;
}

/* Glassmorphism Card Style */
.card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-radius: 16px;
    padding: 2rem;
    text-decoration: none;
    color: inherit;
    display: flex;
    align-items: center;
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    box-shadow: var(--glass-shadow);
    position: relative;
    overflow: hidden;
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.05), transparent);
    transition: left 0.5s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
    border-color: rgba(99, 102, 241, 0.5);
    background: rgba(30, 41, 59, 0.9);
}

.card:hover::before {
    left: 100%;
}

.card-icon {
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: rgba(99, 102, 241, 0.1);
    color: #818cf8;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 1.5rem;
    transition: all 0.3s ease;
}

.card-icon svg {
    width: 24px;
    height: 24px;
}

.card:hover .card-icon {
    background: #818cf8;
    color: #fff;
    transform: scale(1.1);
}

.card-content {
    flex-grow: 1;
}

.card-content h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
    transition: color 0.3s ease;
}

.card:hover .card-content h3 {
    color: #818cf8;
}

.card-content p {
    font-size: 0.9rem;
    color: var(--text-muted);
}

.card-arrow {
    flex-shrink: 0;
    color: var(--text-muted);
    transition: all 0.3s ease;
    opacity: 0;
    transform: translateX(-10px);
}

.card-arrow svg {
    width: 20px;
    height: 20px;
}

.card:hover .card-arrow {
    opacity: 1;
    transform: translateX(0);
    color: #818cf8;
}

/* Disabled Card (for Coming Soon) */
.card.disabled {
    opacity: 0.6;
    cursor: not-allowed;
    pointer-events: none;
}

.card.disabled .card-icon {
    background: rgba(148, 163, 184, 0.1);
    color: var(--text-muted);
}

.footer {
    text-align: center;
    padding-top: 3rem;
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* Animations */
@keyframes fadeInDown {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 640px) {
    .card {
        flex-direction: column;
        text-align: center;
        padding: 1.5rem;
    }
    
    .card-icon {
        margin-right: 0;
        margin-bottom: 1rem;
    }
    
    .card-arrow {
        display: none;
    }
}