#select_card {
            width: 645px;
            margin: 0 auto;
            display: flex;
            justify-content: center;
            align-items: center;
            flex-direction: column;
        }
		#game_title {
			font-weight: bold;
			font-size: 26px; /* 제목 강조 */
			text-align: center;
			color: #2c3e50; /* 어두운 세련된 텍스트 색상 */
			padding: 15px 25px; /* 내부 여백 */
			letter-spacing: 1.5px; /* 글자 간격 */
			border: 2px solid #2c3e50; /* 텍스트 색상과 동일한 테두리 */
			border-radius: 10px; /* 부드러운 모서리 */
			margin-bottom: 20px;
		}
		#instruction{
			text-align: center;
			font-size: 18px;
			color: #555;
			margin-bottom: 20px;
			line-height: 200%;
		}
        .card {
            display: inline-block;
            width: 105px;
            height: 155px;
            border: 2px solid #333;
            border-radius: 10px;
            margin: 10px;
            text-align: center;
            font-size: 24px;
            font-weight: bold;
            cursor: pointer;
            perspective: 1000px;
            transition: transform 0.3s ease, box-shadow 0.3s ease;
        }
        .card:hover {
            transform: translateY(-10px); /* 위로 살짝 이동 */
            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2); /* 그림자 효과 */
        }
        .card.disabled {
            cursor: not-allowed;
            opacity: 0.6;
        }
        .card.disabled:hover {
            transform: none; /* 비활성화된 카드에 애니메이션 작동 안 함 */
            box-shadow: none;
        }
        .card-inner {
            width: 100%;
            height: 100%;
            position: relative;
            transform-style: preserve-3d;
            transition: transform 0.6s;
        }
        .card.flipped .card-inner {
            transform: rotateY(180deg);
        }
        .card-front,
        .card-back {
            position: absolute;
            width: 100%;
            height: 100%;
            backface-visibility: hidden;
            display: flex;
            justify-content: center;
            align-items: center;
            border-radius: 10px;
        }
        .card-front {
			    background-image: url(cardbg.png);
        }
        .card-back {
            background-color: #4CAF50;
            color: #fff;
            transform: rotateY(180deg);
        }
        #result {
            margin-top: 20px;
            font-size: 18px;
        }