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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.container {
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
    max-width: 500px;
    width: 100%;
    padding: 30px;
}

.screen {
    display: none;
    flex-direction: column;
    gap: 25px;
}

.screen.active {
    display: flex;
}

h1, h2 {
    text-align: center;
    color: #333;
}

h1 { font-size: 2.2em; }
h2 { font-size: 1.8em; }

.button-group {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin-top: 20px;
}

.btn-primary, .btn-secondary, .btn-difficulty {
    padding: 15px 25px;
    font-size: 1.2em;
    border: none;
    border-radius: 12px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.2s;
    width: 100%;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(102,126,234,0.4);
}

.btn-secondary {
    background: white;
    color: #667eea;
    border: 2px solid #667eea;
}

.btn-secondary:hover {
    background: #667eea;
    color: white;
}

.btn-difficulty {
    background: #f0f0f0;
    color: #333;
}

.btn-difficulty:hover {
    background: #667eea;
    color: white;
}

.profile-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 15px;
    margin: 20px 0;
}

.profile-card {
    border: 3px solid transparent;
    border-radius: 15px;
    padding: 20px 10px;
    text-align: center;
    cursor: pointer;
    transition: 0.3s;
}

.profile-card:hover {
    transform: scale(1.05);
}

.profile-card.selected {
    border-color: #667eea;
    box-shadow: 0 5px 15px rgba(102,126,234,0.3);
}

.profile-icon {
    font-size: 3em;
}

.profile-name {
    font-size: 1.3em;
    font-weight: 600;
    margin: 10px 0 5px;
}

.difficulty-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 15px;
    margin: 20px 0;
}

.selected-info {
    text-align: center;
    font-size: 1.2em;
    color: #666;
}

.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.timer {
    font-size: 2em;
    font-weight: bold;
    color: #4CAF50;
}

.progress-bar {
    height: 10px;
    background: #e0e0e0;
    border-radius: 5px;
    margin-bottom: 30px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #667eea, #764ba2);
    width: 0%;
    transition: width 0.3s;
}

.question {
    font-size: 2.5em;
    text-align: center;
    margin: 30px 0;
    font-weight: bold;
    color: #333;
}

.answer-area {
    display: flex;
    gap: 10px;
    margin: 20px 0;
}

#answer-input {
    flex: 1;
    padding: 20px;
    font-size: 2em;
    text-align: center;
    border: 2px solid #e0e0e0;
    border-radius: 12px;
    font-family: monospace;
}

#answer-input:focus {
    border-color: #667eea;
    outline: none;
}

.feedback {
    text-align: center;
    font-size: 1.2em;
    min-height: 2em;
    color: #666;
}

.hidden {
    display: none;
}

.big-score {
    font-size: 4em;
    text-align: center;
    color: #667eea;
    margin: 20px 0;
}

#results-container {
    display: flex;
    flex-direction: column;
    gap: 20px;
    max-height: 400px;
    overflow-y: auto;
    padding: 10px 0;
}

.player-result-card {
    background: #f8f9fa;
    border-radius: 12px;
    padding: 20px;
    border-left: 5px solid #667eea;
}

.player-result-card h3 {
    margin-bottom: 10px;
    color: #333;
}

.player-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 15px;
    margin: 15px 0;
}

.stat-item {
    background: white;
    padding: 10px;
    border-radius: 8px;
    text-align: center;
}

.stat-label {
    font-size: 0.9em;
    color: #666;
    margin-bottom: 5px;
}

.stat-value {
    font-size: 1.4em;
    font-weight: bold;
    color: #333;
}

.question-type-stats {
    display: flex;
    justify-content: space-around;
    margin-top: 15px;
    font-size: 0.9em;
    color: #666;
}

@media (max-width: 600px) {
    .profile-grid, .difficulty-grid {
        grid-template-columns: 1fr;
    }
}