.theme-selector {
    width: min(1120px, calc(100% - 32px));
    margin: 40px auto;
    padding: 32px;
    text-align: center;
}

.theme-selector h2 {
    margin: 0 0 10px;
    font-size: clamp(2rem, 4vw, 3rem);
    color: #f8fafc;
}

.theme-selector > p {
    margin: 0 auto 32px;
    max-width: 640px;
    color: #94a3b8;
    font-size: 1rem;
}

.theme-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
    gap: 20px;
}

.theme-card {
    position: relative;
    min-height: 220px;
    padding: 24px;
    overflow: hidden;
    text-align: left;
    cursor: pointer;

    background: rgba(15, 23, 42, 0.92);
    border: 2px solid rgba(148, 163, 184, 0.12);
    border-radius: 20px;

    transition:
        transform 180ms ease,
        border-color 180ms ease,
        box-shadow 180ms ease;
}

.theme-card:hover {
    transform: translateY(-6px);
    border-color: rgba(129, 140, 248, 0.75);
    box-shadow: 0 20px 45px rgba(15, 23, 42, 0.45);
}

.theme-card.selected {
    border-color: #818cf8;
    box-shadow:
        0 0 0 4px rgba(129, 140, 248, 0.15),
        0 20px 45px rgba(15, 23, 42, 0.5);
}

.theme-icon {
    display: block;
    margin-bottom: 24px;
    font-size: 2.5rem;
}

.theme-card h3 {
    margin: 0 0 8px;
    color: #f8fafc;
    font-size: 1.2rem;
}

.theme-card p {
    margin: 0 0 24px;
    color: #cbd5e1;
    line-height: 1.6;
}

.theme-colors {
    display: flex;
    gap: 8px;
    margin-top: auto;
}

.theme-color {
    width: 28px;
    height: 28px;
    border: 2px solid rgba(255, 255, 255, 0.18);
    border-radius: 50%;
}

#continueBtn {
    margin-top: 34px;
    padding: 14px 36px;

    color: #e2e8f0;
    background: #475569;
    border: 0;
    border-radius: 12px;

    font-size: 1rem;
    font-weight: 700;
    cursor: not-allowed;
    opacity: 0.7;

    transition:
        transform 180ms ease,
        background 180ms ease,
        opacity 180ms ease;
}

#continueBtn.enabled {
    color: white;
    background: linear-gradient(135deg, #6366f1, #8b5cf6);
    cursor: pointer;
    opacity: 1;
}

#continueBtn.enabled:hover {
    transform: translateY(-2px);
}

@media (max-width: 640px) {
    .theme-selector {
        margin: 20px auto;
        padding: 20px 0;
    }

    .theme-grid {
        grid-template-columns: 1fr;
    }
}