:root {
    --bg-color: #FFFBF0;
    --text-color: #5D5D5D;
    --card-bg: #FFFFFF;
    
    /* Cozy Palette */
    --primary-color: #B5EAD7; /* Pastel Green */
    --secondary-color: #FFDAC1; /* Peach */
    --accent-color: #FFB7B2; /* Pastel Pink */
    --btn-bg: #E2F0CB;
    --btn-hover: #C5E1A5;
    --btn-primary-bg: #B5EAD7;
    --btn-primary-hover: #9bd6c0;
    
    --shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    --radius: 12px;
}

body {
    margin: 0;
    font-family: 'Nunito', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    display: flex;
    justify-content: center;
    align-items: flex-start;
    min-height: 100vh;
}

.game-container {
    width: 100%;
    max-width: 900px;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 20px;
    box-sizing: border-box;
}

header {
    text-align: center;
    margin-bottom: 20px;
}

h1 {
    margin: 10px 0 5px 0;
    color: var(--secondary-color);
    font-size: 3rem;
    text-shadow: 2px 2px 0px var(--accent-color);
    letter-spacing: 1px;
}

.subtitle {
    margin-top: 0;
    color: var(--primary-color);
    font-weight: bold;
    font-size: 1.2rem;
    letter-spacing: 1px;
}

/* UI Elements */
button, .btn {
    font-family: inherit;
    font-weight: bold;
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    cursor: pointer;
    background-color: var(--btn-bg);
    color: #444;
    font-size: 1rem;
    transition: transform 0.1s, background-color 0.2s;
    box-shadow: 0 2px 0 rgba(0, 0, 0, 0.1);
    text-transform: uppercase;
}

button:active, .btn:active {
    transform: translateY(2px);
    box-shadow: none;
}

button:hover, .btn:hover {
    background-color: var(--btn-hover);
}

.btn-primary {
    background-color: var(--btn-primary-bg);
}

.btn-primary:hover {
    background-color: var(--btn-primary-hover);
}

.btn-small {
    padding: 8px 16px;
    font-size: 0.9rem;
}

/* Toggle Switch */
.toggle-container {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 15px;
    margin-bottom: 25px;
    font-weight: bold;
    color: var(--text-color);
}

.switch {
    position: relative;
    display: inline-block;
    width: 50px;
    height: 28px;
}

.switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #EEE;
    transition: .4s;
    border-radius: 28px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 20px;
    width: 20px;
    left: 4px;
    bottom: 4px;
    background-color: white;
    transition: .4s;
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
    border-radius: 50%;
}

input:checked + .slider {
    background-color: var(--primary-color);
}

input:checked + .slider:before {
    transform: translateX(22px);
}

select, input[type="text"] {
    padding: 12px;
    font-family: inherit;
    font-size: 1rem;
    border: 2px solid #EEE;
    border-radius: 8px;
    width: 100%;
    box-sizing: border-box;
    margin-bottom: 15px;
    outline: none;
    transition: border-color 0.3s;
}

select:focus, input[type="text"]:focus {
    border-color: var(--primary-color);
}

/* Screens */
.menu-screen {
    display: none;
    width: 100%;
    flex-direction: column;
    align-items: center;
}

.menu-screen.active {
    display: flex;
}

.menu-box {
    background: var(--card-bg);
    padding: 40px;
    border-radius: 20px;
    box-shadow: var(--shadow);
    text-align: center;
    width: 100%;
    max-width: 400px;
}

.menu-box h2 {
    color: #444;
    margin-top: 0;
}

.mode-buttons {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-top: 15px;
}

/* Game Area */
.game-header {
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

#score-board {
    display: flex;
    gap: 20px;
    font-size: 1.2rem;
    font-weight: bold;
}

.player-score {
    padding: 8px 16px;
    border-radius: 8px;
    background: #EEE;
    transition: background 0.3s, color 0.3s;
}

.player-score.active-turn {
    background: var(--primary-color);
    color: #222;
}

.player-score.hidden {
    display: none;
}

.game-controls {
    display: flex;
    gap: 10px;
}

/* Board */
.board {
    display: grid;
    /* We'll use CSS variables to adjust grid based on card count, but default to 4 cols */
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
    width: 100%;
    perspective: 1000px; /* For 3D flip */
}

/* Cards */
.card {
    background: transparent;
    width: 100%;
    aspect-ratio: 3/4; /* Nice card shape */
    cursor: pointer;
    position: relative;
    border-radius: var(--radius);
    transform-style: preserve-3d;
    transition: transform 0.6s cubic-bezier(0.4, 0.0, 0.2, 1);
}

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

.card-face {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    border-radius: var(--radius);
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: var(--shadow);
    font-size: 1.1rem;
    font-weight: bold;
    padding: 8px;
    box-sizing: border-box;
    text-align: center;
    word-break: break-word;
}

/* Back of the card (Blue Gradient) */
.card-back {
    background: radial-gradient(circle, #598ea8, #1d3b4d);
    border: 2px solid white;
}

/* Front of the card */
.card-front {
    background: var(--card-bg);
    color: var(--text-color);
    transform: rotateY(180deg);
    border: 2px solid #EEE;
}

.card.matched .card-front {
    background: var(--btn-bg);
    border-color: var(--primary-color);
    color: #333;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    justify-content: center;
    align-items: center;
    z-index: 100;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: var(--card-bg);
    padding: 30px;
    border-radius: 20px;
    box-shadow: var(--shadow);
    width: 90%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
}

.pairs-container {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-bottom: 15px;
    max-height: 40vh;
    overflow-y: auto;
    padding-right: 5px;
}

.pair-input {
    display: flex;
    align-items: center;
    gap: 10px;
}

.pair-input input {
    margin-bottom: 0;
}

.modal-actions {
    display: flex;
    gap: 10px;
    margin-top: 20px;
}

.modal-actions button {
    flex: 1;
}

/* Toast Message */
.toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: #333;
    color: #FFF;
    padding: 10px 20px;
    border-radius: 30px;
    font-weight: bold;
    opacity: 0;
    transition: transform 0.3s, opacity 0.3s;
    z-index: 200;
}

.toast.show {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
}

.status-msg {
    margin-top: 15px;
    font-weight: bold;
    color: #e74c3c;
}

@media (max-width: 600px) {
    .board {
        grid-template-columns: repeat(4, 1fr) !important;
        width: 100% !important;
        gap: 8px;
    }
    .card-face {
        font-size: 0.9rem;
        padding: 5px;
    }
}
@media (max-width: 450px) {
    .board {
        grid-template-columns: repeat(3, 1fr) !important;
        width: 100% !important;
        gap: 6px;
    }
}

/* Online Multiplayer styles */
#waiting-screen .menu-box {
    border: 3px dashed var(--accent-color);
}

.lobby-card {
    background: var(--card-bg);
    padding: 40px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    text-align: center;
    width: 90%;
    max-width: 400px;
    box-sizing: border-box;
}

.lobby-card h1 {
    margin: 0;
    color: var(--secondary-color);
    font-size: 2.8rem !important;
    text-shadow: 2px 2px 0 var(--accent-color) !important;
}

.lobby-card .subtitle {
    color: var(--primary-color);
    font-weight: 800;
    letter-spacing: 1px;
    text-transform: uppercase;
    margin-bottom: 20px;
}

/* Rounded Pill Buttons for Lobby */
.lobby-card button, .lobby-card .btn {
    border: none;
    padding: 14px 20px;
    border-radius: 50px;
    font-family: inherit;
    font-weight: 800;
    cursor: pointer;
    font-size: 1rem;
    transition: transform 0.1s, background-color 0.2s;
    width: 100%;
    margin: 5px 0;
    box-shadow: none; /* remove retro box shadow in lobby for clean look */
    text-transform: uppercase;
}

.lobby-card button:active, .lobby-card .btn:active {
    transform: scale(0.98);
}

.lobby-card .btn-primary {
    background-color: var(--btn-primary-bg);
    color: #444;
}

.lobby-card .btn-primary:hover {
    background-color: var(--btn-primary-hover);
}

.lobby-card .btn-secondary {
    background-color: var(--btn-bg);
    color: #555;
}

.lobby-card .btn-secondary:hover {
    background-color: var(--btn-hover);
}

/* Styled Inputs & Selects for Lobby */
.lobby-card input[type="text"],
.lobby-card select {
    width: 100%;
    padding: 15px;
    border: 3px solid #EEE;
    border-radius: 12px;
    font-size: 1.2rem;
    box-sizing: border-box;
    font-family: inherit;
    font-weight: bold;
    color: #555;
    outline: none;
    text-align: center;
    margin-bottom: 10px;
    transition: border-color 0.3s;
}

.lobby-card input[type="text"]:focus,
.lobby-card select:focus {
    border-color: var(--primary-color);
}

.lobby-card .join-section {
    display: flex;
    gap: 10px;
}

.lobby-card .join-section input {
    margin-bottom: 0;
    flex: 1.2;
    text-transform: uppercase;
}

.lobby-card .join-section button {
    flex: 0.8;
    margin: 0;
}