:root {
    --primary: #4361ee;
    --primary-light: #4895ef;
    --secondary: #3f37c9;
    --dark: #1b263b;
    --light: #f8f9fa;
    --success: #4cc9f0;
    --danger: #f72585;
    --warning: #f8961e;
    --info: #560bad;
    --border-radius: 12px;
    --box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
}

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

body {
    font-family: 'Noto Sans SC', sans-serif;
    background-color: #f0f2f5;
    color: var(--dark);
    line-height: 1.6;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.container {
    max-width: 800px;
    width: 100%;
    background: white;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    padding: 30px;
    margin-top: 30px;
    position: relative;
    overflow: hidden;
}

.container::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 8px;
    background: linear-gradient(90deg, var(--primary), var(--primary-light));
}

h1 {
    color: var(--dark);
    text-align: center;
    margin-bottom: 10px;
    font-weight: 700;
    font-size: 2.2rem;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.subtitle {
    text-align: center;
    color: #6c757d;
    margin-bottom: 30px;
    font-weight: 300;
}

.game-area {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 25px;
}

.idiom-display {
    font-size: 2rem;
    font-weight: 500;
    text-align: center;
    margin: 20px 0;
    min-height: 60px;
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 8px;
}

.character {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    width: 50px;
    height: 50px;
    border-radius: 8px;
    background-color: #f8f9fa;
    transition: all 0.3s ease;
}

.blank {
    background-color: #e9ecef;
    color: var(--primary);
    font-weight: bold;
    position: relative;
    border: 2px dashed #adb5bd;
}

.blank::after {
    content: attr(data-index);
    position: absolute;
    bottom: -20px;
    font-size: 0.8rem;
    color: var(--primary);
}

.filled {
    background-color: var(--success);
    color: white;
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(76, 201, 240, 0.4);
}

.input-group {
    display: flex;
    gap: 10px;
    width: 100%;
    max-width: 400px;
}

input {
    flex: 1;
    padding: 12px 15px;
    border: 2px solid #dee2e6;
    border-radius: var(--border-radius);
    font-size: 1.2rem;
    text-align: center;
    transition: all 0.3s;
}

input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.2);
}

button {
    padding: 12px 25px;
    border: none;
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

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

.btn-primary:hover {
    background-color: var(--secondary);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(63, 55, 201, 0.3);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-lg {
    padding: 15px 30px;
    font-size: 1.1rem;
}

.score-display {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--dark);
    margin-top: 20px;
    text-align: center;
}

.score-value {
    color: var(--primary);
    font-size: 2rem;
}

.explanation {
    margin-top: 30px;
    padding: 20px;
    background-color: #f8f9fa;
    border-radius: var(--border-radius);
    border-left: 4px solid var(--primary);
    display: none;
    animation: fadeIn 0.5s;
}

.explanation-title {
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--dark);
}

.idiom-word {
    color: var(--primary);
    font-weight: 500;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.game-over {
    text-align: center;
    margin-top: 20px;
    color: var(--danger);
    font-weight: 500;
    display: none;
}

.progress-container {
    width: 100%;
    height: 8px;
    background-color: #e9ecef;
    border-radius: 4px;
    margin-bottom: 20px;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--primary-light));
    width: 0%;
    transition: width 0.3s;
}

@media (max-width: 600px) {
    .container {
        padding: 20px;
    }
    
    h1 {
        font-size: 1.8rem;
    }
    
    .idiom-display {
        font-size: 1.5rem;
    }
    
    .character {
        width: 40px;
        height: 40px;
    }
    
    .input-group {
        flex-direction: column;
    }
}