:root {
    --primary-color: #007bff;
    --secondary-color: #ffde00;
    --background-color: #f0f8ff;
    --card-bg: #ffffff;
    --text-color: #333;
    --card-size: clamp(60px, 18vw, 120px);
}

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

body {
    font-family: 'Arial', sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: var(--background-color);
    color: var(--text-color);
    padding: 1rem;
}

#game-container {
    text-align: center;
}

h1, h2 {
    color: var(--primary-color);
    text-shadow: 1px 1px 2px rgba(0,0,0,0.1);
}

h2 {
    color: #e51e25;
    margin-bottom: 20px;
}

#stats {
    display: flex;
    justify-content: space-around;
    font-size: 1.2rem;
    margin-bottom: 20px;
}

#game-board {
    display: grid;
    grid-template-columns: repeat(4, var(--card-size));
    grid-template-rows: repeat(3, var(--card-size));
    gap: 10px;
    perspective: 1000px;
    margin-bottom: 20px;
}

.card {
    width: var(--card-size);
    height: var(--card-size);
    position: relative;
    cursor: pointer;
    transform-style: preserve-3d;
    transition: transform 0.6s;
}

.card.flipped {
    transform: rotateY(180deg);
}

.card.matched {
    cursor: default;
}

.card-face {
    width: 100%;
    height: 100%;
    position: absolute;
    backface-visibility: hidden;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
}

.card-back {
    background-color: var(--card-bg);
}

.card-front {
    background-color: var(--secondary-color);
    transform: rotateY(180deg);
}

.card-face img {
    width: 90%;
    height: 90%;
    object-fit: contain;
}

#restart-button, .modal-content button {
    padding: 10px 20px;
    font-size: 1.2rem;
    border: none;
    border-radius: 5px;
    background-color: var(--primary-color);
    color: white;
    cursor: pointer;
    transition: background-color 0.3s;
}

#restart-button:hover, .modal-content button:hover {
    background-color: #0056b3;
}

/* Modal Styles */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.6);
    display: flex;
    justify-content: center;
    align-items: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s, visibility 0.3s;
}

.modal-overlay.show {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    background-color: white;
    padding: 2rem;
    border-radius: 10px;
    text-align: center;
    transform: scale(0.8);
    transition: transform 0.3s;
}

.modal-overlay.show .modal-content {
    transform: scale(1);
}

.modal-content h2 {
    margin-bottom: 1rem;
}

.modal-content p {
    margin-bottom: 1.5rem;
}