:root {
    --bg-color: #f4f7f6;
    --text-main: #2d3748;
    --text-sub: #718096;
    --card-bg: #ffffff;
    --shadow: 0 10px 25px rgba(0, 0, 0, 0.05);
    --hover-shadow: 0 15px 35px rgba(79, 172, 254, 0.15);
}

body {
    font-family: 'Noto Sans JP', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    margin: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.header {
    text-align: center;
    padding: 60px 20px 40px;
}

.header h1 {
    font-size: 3rem;
    margin: 0 0 10px;
    background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: 2px;
}

.header p {
    color: var(--text-sub);
    font-size: 1.1rem;
    font-weight: 700;
    margin: 0;
}

.container {
    max-width: 1000px;
    width: 90%;
    padding-bottom: 60px;
}

/* レスポンシブグリッド: 画面幅に応じてカラム数が自動変化 */
.game-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.game-card {
    background: var(--card-bg);
    border-radius: 20px;
    padding: 40px 20px;
    text-decoration: none;
    color: inherit;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    box-shadow: var(--shadow);
    transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275), box-shadow 0.3s ease;
    border: 2px solid transparent;
}

.game-card:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: var(--hover-shadow);
    border-color: rgba(79, 172, 254, 0.3);
}

.card-icon {
    width: 110px;
    height: 110px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    margin-bottom: 25px;
    box-shadow: inset 0 -4px 10px rgba(0,0,0,0.08);
}

.shogi-icon-bg {
    background: #fff8e1;
}

.card-content h2 {
    font-size: 1.6rem;
    font-weight: 900;
    margin: 0 0 10px;
    color: var(--text-main);
}

.card-content p {
    color: var(--text-sub);
    margin: 0;
    font-weight: 500;
    line-height: 1.5;
}

/* 準備中カードのスタイル */
.coming-soon {
    cursor: not-allowed;
    background: #f8fafc;
    border: 2px dashed #cbd5e1;
    box-shadow: none;
}

.coming-soon:hover {
    transform: none;
    box-shadow: none;
    border-color: #cbd5e1;
}

.empty-icon-bg {
    background: #f1f5f9;
}

/* スマホ用調整 */
@media (max-width: 600px) {
    .header { padding: 40px 20px 30px; }
    .header h1 { font-size: 2.2rem; }
    .game-card { padding: 30px 20px; }
}