/* 练习页面通用样式 */
:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary: #8b5cf6;
    --success: #16a34a;
    --warning: #f59e0b;
    --danger: #dc2626;
    --bg: #f1f5f9;
    --card: rgba(255, 255, 255, 0.95);
    --text-main: #0f172a;
    --text-muted: #64748b;
    --border: rgba(15, 23, 42, 0.1);
}

body {
    background: linear-gradient(135deg, #f1f5f9 0%, #e2e8f0 50%, #f1f5f9 100%);
    background-size: 400% 400%;
    animation: gradientShift 15s ease infinite;
    min-height: 100vh;
    font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    color: var(--text-main);
    margin: 0;
    padding: 0;
}

@keyframes gradientShift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.practice-page {
    padding: 40px 32px;
}

.hero-section {
    text-align: center;
    margin-bottom: 48px;
    color: var(--text-main);
}

.hero-title {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 12px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.02em;
}

.hero-title .emoji {
    font-size: 28px;
    display: inline-block;
    vertical-align: middle;
    margin-right: 8px;
}

.hero-subtitle {
    font-size: 18px;
    color: var(--text-muted);
    margin-bottom: 0;
    font-weight: 400;
}

.setup-panel, .practice-panel {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-radius: 24px;
    box-shadow: 
        0 8px 32px rgba(0, 0, 0, 0.08),
        0 2px 8px rgba(0, 0, 0, 0.04);
    border: 1px solid var(--border);
    overflow: hidden;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.setup-panel:hover, .practice-panel:hover {
    transform: translateY(-2px);
    box-shadow: 
        0 12px 40px rgba(0, 0, 0, 0.12),
        0 4px 12px rgba(0, 0, 0, 0.06);
}

.panel-header {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    padding: 24px 32px;
    text-align: center;
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.2);
}

.panel-title {
    font-size: 20px;
    font-weight: 600;
    margin: 0;
    letter-spacing: -0.01em;
}

.panel-title .emoji {
    font-size: 18px;
    display: inline-block;
    vertical-align: middle;
    margin-right: 8px;
}

.panel-content {
    padding: 40px 32px;
}

.settings-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
    margin-bottom: 40px;
}

.setting-card {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-radius: 16px;
    padding: 24px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
    border: 1px solid var(--border);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.setting-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
    border-color: var(--primary-light);
    background: rgba(255, 255, 255, 0.95);
}

.setting-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-main);
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    gap: 8px;
    letter-spacing: -0.01em;
}

.voice-settings {
    display: flex;
    flex-direction: column;
    gap: 0;
}

.voice-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.voice-label {
    font-weight: 600;
    color: var(--text-main);
    font-size: 14px;
    margin-bottom: 8px;
}

.voice-select {
    padding: 10px 14px;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--card);
    font-size: 14px;
    font-weight: 500;
    color: var(--text-main);
    cursor: pointer;
    transition: all 0.2s ease;
    font-family: 'Inter', system-ui, sans-serif;
}

.voice-select:hover {
    border-color: var(--primary);
}

.voice-select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.stats-section {
    margin: 30px 0;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 16px;
}

.stat-card {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    color: var(--text-main);
    padding: 24px 20px;
    border-radius: 16px;
    text-align: center;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border: 1px solid var(--border);
}

.stat-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
    background: rgba(255, 255, 255, 0.95);
}

.stat-number {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 8px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.02em;
}

.stat-label {
    font-size: 14px;
    color: var(--text-muted);
    font-weight: 500;
}

.start-button {
    text-align: center;
    margin-top: 30px;
}

.btn-start {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    border: none;
    padding: 14px 32px;
    border-radius: 10px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 2px 6px rgba(99, 102, 241, 0.3);
    font-family: 'Inter', system-ui, sans-serif;
}

.btn-start:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.4);
}

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

.hidden {
    display: none;
}

.progress-bar {
    width: 100%;
    height: 6px;
    background: var(--border);
    border-radius: 3px;
    overflow: hidden;
    position: relative;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    transition: width 0.3s ease;
    border-radius: 3px;
    box-shadow: 0 1px 3px rgba(99, 102, 241, 0.3);
}

.vocab-card, .quiz-card {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-radius: 20px;
    padding: 40px 32px;
    text-align: center;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
    margin: 24px 0;
    border: 1px solid var(--border);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
}

.vocab-card:hover, .quiz-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
    background: rgba(255, 255, 255, 0.95);
}

.vocab-card-clickable {
    transition: all 0.2s ease;
    cursor: pointer;
}

.vocab-card-clickable:active {
    transform: scale(0.98);
}

.vocab-card-clickable:hover {
    border-color: var(--primary);
}

.vocab-word {
    font-size: 48px;
    font-weight: 700;
    color: var(--text-main);
    margin-bottom: 12px;
    letter-spacing: -0.02em;
}

.vocab-phonetic {
    font-size: 18px;
    color: var(--text-muted);
    margin-bottom: 12px;
    font-weight: 400;
    font-style: italic;
}

.vocab-pos {
    display: inline-block;
    padding: 4px 12px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    border-radius: 6px;
    font-size: 12px;
    font-weight: 600;
    margin-bottom: 24px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    box-shadow: 0 1px 3px rgba(99, 102, 241, 0.3);
}

.vocab-definition {
    font-size: 16px;
    color: var(--text-main);
    line-height: 1.6;
    max-width: 600px;
    margin: 0 auto;
    padding: 20px;
    background: var(--bg);
    border-radius: 8px;
    border-left: 3px solid var(--primary);
}

.quiz-question {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-main);
    margin-bottom: 24px;
    letter-spacing: -0.01em;
}

.quiz-options {
    display: grid;
    gap: 12px;
    margin-bottom: 24px;
}

.quiz-option {
    padding: 16px 20px;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    text-align: left;
    font-size: 15px;
    font-weight: 500;
    color: var(--text-main);
    font-family: 'Inter', system-ui, sans-serif;
}

.quiz-option:hover {
    border-color: var(--primary-light);
    background: rgba(99, 102, 241, 0.1);
    transform: translateY(-2px);
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.2);
}

.quiz-option.selected {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    border-color: var(--primary);
    box-shadow: 0 2px 6px rgba(99, 102, 241, 0.3);
}

.quiz-option.correct {
    background: var(--success);
    color: white;
    border-color: var(--success);
}

.quiz-option.wrong {
    background: var(--danger);
    color: white;
    border-color: var(--danger);
}

.quiz-option:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.controls {
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-top: 24px;
}

.control-btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    font-size: 15px;
    transition: all 0.2s ease;
    min-height: 48px;
    min-width: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-family: 'Inter', system-ui, sans-serif;
}

.control-btn.primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    box-shadow: 0 2px 6px rgba(99, 102, 241, 0.3);
}

.control-btn.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.4);
}

.control-btn.secondary {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    color: var(--text-main);
    border: 1px solid var(--border);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
}

.control-btn.secondary:hover {
    border-color: var(--primary-light);
    color: var(--primary);
    background: rgba(99, 102, 241, 0.1);
    transform: translateY(-2px);
}

.loading {
    text-align: center;
    padding: 40px;
    color: var(--text-muted);
}

.empty {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-muted);
}

@media (max-width: 768px) {
    .practice-page {
        padding: 20px;
    }
    
    .hero-title {
        font-size: 28px;
    }
    
    .hero-subtitle {
        font-size: 15px;
    }
    
    .panel-content {
        padding: 20px;
    }
}

@media (max-width: 480px) {
    .practice-page {
        padding: 10px;
    }
    
    .hero-title {
        font-size: 24px;
    }
    
    .hero-subtitle {
        font-size: 14px;
    }
}