:root {
    --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --primary-color: #667eea;
    --secondary-color: #764ba2;
    --text-primary: #2d3748;
    --text-secondary: #718096;
    --bg-light: #f7fafc;
    --bg-white: #ffffff;
    --border-color: #e2e8f0;
    --shadow-lg: 0 10px 40px rgba(0, 0, 0, 0.2);
    --transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    font-size: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    background: #000;
    min-height: 100vh;
    overflow: hidden;
    -webkit-font-smoothing: antialiased;
}

#app {
    width: 100vw;
    height: 100vh;
    display: flex;
    background: #000;
    position: relative;
}

#progress-container {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: linear-gradient(to bottom, rgba(0,0,0,0.8) 0%, transparent 100%);
    padding: 1rem 1.5rem;
    transform: translateY(0);
    transition: transform 0.4s ease;
}

#progress-container.hidden-nav {
    transform: translateY(-100%);
}

@media screen and (min-width: 1024px) and (orientation: landscape),
       screen and (min-width: 768px) and (max-width: 1024px) and (orientation: landscape) {
    #app {
        flex-direction: row;
    }
    
    #progress-container {
        position: fixed;
        top: 0;
        left: 0;
        bottom: 0;
        right: auto;
        width: 100px;
        background: rgba(0,0,0,0.85);
        padding: 1rem 0.5rem;
        transform: translateX(0);
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        border-right: 1px solid rgba(255,255,255,0.1);
    }
    
    #progress-container.hidden-nav {
        transform: translateX(-100%);
    }
    
    .progress-wrapper {
        flex-direction: column;
        align-items: center;
        width: 100%;
    }
    
    .progress-track {
        width: 4px;
        height: 60px;
        margin-bottom: 1rem;
        margin-right: 0;
    }
    
    .progress-fill {
        width: 100%;
        height: 0;
        transition: height 0.5s ease;
    }
    
    .progress-steps {
        flex-direction: column;
        gap: 0.75rem;
        margin-top: 0;
        width: 100%;
    }
    
    .step {
        flex-direction: row;
        gap: 0.5rem;
        justify-content: flex-start;
        padding: 0.5rem;
        border-radius: 8px;
        transition: all 0.3s ease;
    }
    
    .step:hover {
        background: rgba(255,255,255,0.1);
    }
    
    .step.active {
        background: rgba(102, 126, 234, 0.2);
    }
    
    .step-icon {
        width: 24px;
        height: 24px;
        flex-shrink: 0;
    }
    
    .step-icon svg {
        width: 14px;
        height: 14px;
    }
    
    .step-label {
        font-size: 0.7rem;
        writing-mode: horizontal-tb;
        text-orientation: mixed;
        white-space: nowrap;
    }
    
    #content {
        margin-left: 100px;
        width: calc(100vw - 100px);
    }
}

.progress-wrapper {
    max-width: 1200px;
    margin: 0 auto;
}

.progress-track {
    height: 4px;
    background: rgba(255,255,255,0.2);
    border-radius: 2px;
    margin-bottom: 0.75rem;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--primary-gradient);
    width: 0;
    transition: width 0.5s ease;
    border-radius: 2px;
}

.progress-steps {
    display: flex;
    justify-content: center;
    gap: 2rem;
}

.step {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
    position: relative;
    cursor: pointer;
    transition: var(--transition);
}

.step-icon {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: rgba(255,255,255,0.15);
    transition: var(--transition);
    z-index: 2;
    color: rgba(255,255,255,0.7);
}

.step-icon svg {
    display: block;
}

.step-label {
    font-size: 0.7rem;
    color: rgba(255,255,255,0.6);
    font-weight: 500;
    text-align: center;
    transition: var(--transition);
}

.step.active .step-icon {
    background: var(--primary-gradient);
    color: white;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.3);
    transform: scale(1.1);
}

.step.active .step-label {
    color: white;
    font-weight: 600;
}

.step.completed .step-icon {
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
    color: white;
}

.step.completed .step-label {
    color: #48bb78;
}

.step:hover .step-icon {
    background: rgba(102, 126, 234, 0.4);
    color: white;
    transform: scale(1.05);
}

.step:hover .step-label {
    color: white;
}

.step.locked:hover .step-icon {
    background: rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.5);
    transform: none;
}

.step.locked:hover .step-label {
    color: rgba(255, 255, 255, 0.5);
}

#content {
    flex: 1;
    position: relative;
    overflow: hidden;
}

.stage {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    transform: translateX(100%);
}

.stage.active {
    opacity: 1;
    visibility: visible;
    transform: translateX(0);
}

.stage.prev {
    transform: translateX(-100%);
}

.stage-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    position: relative;
    z-index: 1;
    width: 100%;
    height: 100%;
}

.cover-wrapper, .intro-wrapper, .score-wrapper {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    position: relative;
}

.iframe-wrapper {
    width: 100%;
    height: 100%;
    flex: 1;
    display: flex;
    flex-direction: column;
    background: #000;
    position: relative;
}

.cover-card {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    position: relative;
    cursor: pointer;
}

.cover-image-container {
    flex: 1;
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    overflow: hidden;
}

#cover-image {
    width: 100%;
    height: 100%;
    object-fit: contain;
    transition: transform 0.3s ease;
}

.cover-card:hover #cover-image {
    transform: scale(1.02);
}

.cover-info {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 2rem;
    background: linear-gradient(to top, rgba(0,0,0,0.8) 0%, transparent 100%);
    text-align: center;
}

#cover-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: white;
    margin-bottom: 0.5rem;
    text-shadow: 2px 2px 8px rgba(0,0,0,0.5);
}

.cover-meta {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    flex-wrap: wrap;
    font-size: 1rem;
    color: rgba(255,255,255,0.8);
}

.cover-meta span {
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.cover-actions {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    z-index: 10;
}

.intro-wrapper {
    width: 100%;
    height: 100%;
    position: relative;
}

.intro-header {
    position: absolute;
    top: 80px;
    left: 0;
    right: 0;
    text-align: center;
    z-index: 10;
    padding: 1rem;
}

.stage-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
    text-shadow: 2px 2px 8px rgba(0,0,0,0.5);
}

.intro-content {
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    background: #000;
}

#situation-content {
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
}

.situation-image-wrapper {
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: default;
}

.situation-image {
    width: 100%;
    height: 100%;
    object-fit: contain;
    transition: opacity 0.4s ease-in-out;
}

#situation-content img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    cursor: pointer;
}

#situation-content video {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.intro-actions-container {
    position: absolute;
    bottom: 3rem;
    left: 50%;
    transform: translateX(-50%);
    z-index: 10;
    animation: fadeInUp 0.5s ease;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translate(-50%, 20px);
    }
    to {
        opacity: 1;
        transform: translate(-50%, 0);
    }
}

.iframe-wrapper {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    background: #000;
}

.iframe-container {
    flex: 1;
    width: 100%;
    background: #fff;
    overflow: hidden;
}

.iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
    display: block;
}

.iframe-actions {
    padding: 1rem;
    display: flex;
    justify-content: center;
    background: linear-gradient(to top, rgba(0,0,0,0.5) 0%, transparent 100%);
}

.practice-wrapper {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 2rem;
    box-sizing: border-box;
    overflow-y: auto;
}

.practice-menu {
    flex: 1;
    min-height: fit-content;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 2rem;
    padding: 2rem 1rem;
}

.practice-title {
    font-size: 1.5rem;
    color: white;
    text-align: center;
    margin-bottom: 0.5rem;
}

.practice-buttons {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    width: 100%;
    max-width: 320px;
}

@media screen and (orientation: landscape) {
    .practice-buttons {
        flex-direction: row;
        max-width: 900px;
        justify-content: center;
    }
    
    .practice-btn {
        flex: 1;
        min-width: 200px;
        max-width: 280px;
    }
}

.practice-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    padding: 1.25rem;
    border: none;
    border-radius: 16px;
    background: rgba(255,255,255,0.95);
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.practice-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.2);
}

.practice-btn.completed {
    opacity: 0.7;
}

.practice-btn.completed::after {
    content: '✓ 已完成';
    font-size: 0.75rem;
    color: #48bb78;
    font-weight: 600;
}

.practice-btn-basic {
    border-left: 4px solid #48bb78;
}

.practice-btn-extend {
    border-left: 4px solid #4299e1;
}

.practice-btn-challenge {
    border-left: 4px solid #ed8936;
}

.practice-icon {
    font-size: 2rem;
}

.practice-label {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
}

.practice-desc {
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.practice-score-info {
    margin-top: 1rem;
    padding: 0.75rem 1.5rem;
    background: rgba(255,255,255,0.2);
    border-radius: 25px;
    color: white;
    font-size: 0.9rem;
}

.practice-next-section {
    margin-top: 1.5rem;
    text-align: center;
}

.practice-next-btn {
    background: linear-gradient(135deg, #ffd700 0%, #ffb347 100%);
    color: #333;
    border: none;
    padding: 0.875rem 2rem;
    border-radius: 30px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    box-shadow: 0 4px 15px rgba(255, 215, 0, 0.4);
    transition: all 0.3s ease;
}

.practice-next-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(255, 215, 0, 0.5);
}

.practice-next-btn .arrow {
    font-size: 1.2rem;
    transition: transform 0.3s ease;
}

.practice-next-btn:hover .arrow {
    transform: translateX(5px);
}

.practice-btn {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
    padding: 1.5rem 1.25rem;
    border: none;
    border-radius: 20px;
    background: rgba(255, 255, 255, 0.95);
    cursor: pointer;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 
        0 4px 20px rgba(102, 126, 234, 0.15),
        0 1px 3px rgba(0, 0, 0, 0.1);
    overflow: hidden;
}

.practice-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #667eea, #764ba2, #667eea);
    background-size: 200% 100%;
    animation: shimmer 3s linear infinite;
    opacity: 0;
    transition: opacity 0.3s;
}

@keyframes shimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

.practice-btn:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 
        0 20px 40px rgba(102, 126, 234, 0.25),
        0 10px 20px rgba(0, 0, 0, 0.15);
}

.practice-btn:hover::before {
    opacity: 1;
}

.practice-btn-basic {
    border-left: 5px solid transparent;
    background: linear-gradient(135deg, rgba(72, 187, 120, 0.05) 0%, rgba(255, 255, 255, 0.95) 100%);
}

.practice-btn-basic:hover {
    background: linear-gradient(135deg, rgba(72, 187, 120, 0.15) 0%, rgba(255, 255, 255, 1) 100%);
}

.practice-btn-extend {
    border-left: 5px solid transparent;
    background: linear-gradient(135deg, rgba(66, 153, 225, 0.05) 0%, rgba(255, 255, 255, 0.95) 100%);
}

.practice-btn-extend:hover {
    background: linear-gradient(135deg, rgba(66, 153, 225, 0.15) 0%, rgba(255, 255, 255, 1) 100%);
}

.practice-btn-challenge {
    border-left: 5px solid transparent;
    background: linear-gradient(135deg, rgba(237, 137, 54, 0.05) 0%, rgba(255, 255, 255, 0.95) 100%);
}

.practice-btn-challenge:hover {
    background: linear-gradient(135deg, rgba(237, 137, 54, 0.15) 0%, rgba(255, 255, 255, 1) 100%);
}

.practice-btn.locked {
    opacity: 0.6;
    cursor: not-allowed;
    pointer-events: none;
    background: linear-gradient(135deg, rgba(160, 174, 192, 0.1) 0%, rgba(255, 255, 255, 0.8) 100%);
}

.practice-btn.locked:hover {
    transform: none;
    box-shadow: 
        0 4px 20px rgba(102, 126, 234, 0.15),
        0 1px 3px rgba(0, 0, 0, 0.1);
}

.practice-btn.locked .practice-icon {
    filter: grayscale(100%);
}

.lock-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(2px);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    z-index: 10;
    border-radius: 20px;
}

.lock-icon {
    font-size: 2.5rem;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.2));
}

.lock-text {
    font-size: 0.85rem;
    color: #718096;
    font-weight: 500;
}

.practice-btn.completed-badge {
    position: relative;
}

.practice-btn.completed-badge .badge-overlay {
    position: absolute;
    top: -8px;
    right: -8px;
    width: 44px;
    height: 44px;
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 
        0 4px 12px rgba(72, 187, 120, 0.4),
        0 0 0 3px #fff;
    z-index: 20;
    animation: badgePop 0.5s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

@keyframes badgePop {
    0% { transform: scale(0); opacity: 0; }
    50% { transform: scale(1.2); }
    100% { transform: scale(1); opacity: 1; }
}

.badge-check {
    color: white;
    font-size: 1.3rem;
    font-weight: bold;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}

.practice-icon {
    font-size: 2.5rem;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1));
    transition: transform 0.3s;
}

.practice-btn:hover .practice-icon {
    transform: scale(1.15) rotate(5deg);
}

.practice-label {
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: 0.5px;
}

.practice-desc {
    font-size: 0.85rem;
    color: var(--text-secondary);
    text-align: center;
    line-height: 1.4;
}

.practice-quiz {
    flex: 1;
    display: flex;
    flex-direction: column;
    background: white;
    border-radius: 16px;
    overflow: hidden;
}

.quiz-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem 1rem;
    background: var(--primary-gradient);
    color: white;
}

.quiz-back-btn {
    background: rgba(255,255,255,0.2);
    border: none;
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.85rem;
    flex-shrink: 0;
}

.quiz-header-right {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.quiz-progress {
    font-size: 0.9rem;
    opacity: 0.95;
    background: rgba(255,255,255,0.15);
    padding: 0.35rem 0.75rem;
    border-radius: 12px;
}

.quiz-score-box {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(255,255,255,0.2);
    padding: 0.35rem 0.75rem;
    border-radius: 12px;
}

.quiz-score-box .score-label {
    font-size: 0.85rem;
    opacity: 0.9;
}

.quiz-score-box .score-value {
    position: static !important;
    transform: none !important;
    font-size: 1.25rem !important;
    font-weight: 700 !important;
    color: #ffd700 !important;
    text-shadow: 0 1px 2px rgba(0,0,0,0.2) !important;
    background: none !important;
    -webkit-background-clip: initial !important;
    -webkit-text-fill-color: initial !important;
    background-clip: initial !important;
}

.quiz-content {
    flex: 1;
    padding: 1rem;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.question-container {
    flex: 1;
    max-width: 700px;
    margin: 0 auto;
    padding: 1rem;
    background: white;
    border-radius: 12px;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
}

.question-container.has-image {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.question-image-container {
    display: none;
    margin-bottom: 1rem;
    text-align: center;
}

.question-image-container.has-image {
    display: block;
}

.question-image {
    max-width: 100%;
    max-height: 200px;
    width: auto;
    height: auto;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.question-content {
    flex: 1;
}

@media screen and (orientation: landscape) {
    .question-container.has-image {
        flex-direction: row;
        align-items: flex-start;
        max-width: 900px;
    }
    
    .question-image-container {
        flex: 0 0 40%;
        max-width: 40%;
        margin-bottom: 0;
    }
    
    .question-image {
        max-height: 300px;
        width: 100%;
        object-fit: contain;
    }
    
    .question-content {
        flex: 1;
        min-width: 0;
    }
}

.question-text {
    font-size: 1.1rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.options-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.option-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1rem;
    background: var(--bg-light);
    border-radius: 12px;
    cursor: pointer;
    transition: var(--transition);
}

.option-item:hover {
    background: #e2e8f0;
}

.option-item input[type="radio"] {
    width: 18px;
    height: 18px;
    accent-color: var(--primary-color);
}

.option-item input[type="checkbox"] {
    width: 18px;
    height: 18px;
    accent-color: var(--primary-color);
}

.multichoice-hint {
    font-size: 0.875rem;
    color: #f59e0b;
    margin-bottom: 0.75rem;
    padding-left: 0.25rem;
}

.neutral-option {
    background: var(--bg-light) !important;
    border: 2px solid var(--border-color) !important;
}

.judge-options {
    flex-direction: row;
    justify-content: center;
    gap: 1.5rem;
}

.judge-options .option-item {
    flex: 1;
    max-width: 150px;
    justify-content: center;
}

.fill-input-container {
    display: flex;
    justify-content: center;
}

.fill-input {
    width: 100%;
    max-width: 300px;
    padding: 1rem;
    font-size: 1rem;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    text-align: center;
    transition: var(--transition);
}

.fill-input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.sort-container {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.sort-item {
    padding: 1rem;
    background: var(--bg-light);
    border-radius: 12px;
    cursor: grab;
    text-align: center;
    transition: var(--transition);
}

.sort-item:active {
    cursor: grabbing;
}

.sort-item:hover {
    background: #e2e8f0;
}

.match-container {
    display: flex;
    justify-content: space-around;
    gap: 1rem;
}

.match-column {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.match-item {
    padding: 0.75rem 1rem;
    background: var(--bg-light);
    border: 2px solid transparent;
    border-radius: 8px;
    text-align: center;
    font-size: 0.9rem;
    cursor: grab;
    transition: all 0.3s ease;
    user-select: none;
}

.match-item:hover {
    background: #e2e8f0;
    transform: translateY(-2px);
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.match-item.dragging {
    opacity: 0.5;
    transform: scale(1.05);
    cursor: grabbing;
}

.match-item.drag-over {
    background: var(--primary-color);
    color: white;
    transform: scale(1.1);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.match-item.matched {
    cursor: default;
}

.question-hint {
    margin-top: 1rem;
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.categorize-container {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.categories-row {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.category-box {
    flex: 1;
    min-height: 180px;
    min-width: 200px;
    padding: 0.75rem;
    background: var(--bg-light);
    border-radius: 12px;
    border: 2px dashed var(--border-color);
    transition: all 0.3s ease;
    cursor: pointer;
    overflow: visible;
    display: flex;
    flex-direction: column;
}

.category-items {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
    min-height: 120px;
    padding: 0.5rem;
    overflow: visible;
    flex: 1;
}

.category-box:hover {
    border-color: var(--primary-color);
    background: rgba(102, 126, 234, 0.1);
    transform: scale(1.02);
}

.category-box:active {
    transform: scale(0.98);
}

.category-items {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
    min-height: 100px;
    padding: 0.5rem;
    overflow: visible;
}

.category-title {
    font-weight: 600;
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

@media screen and (max-width: 768px) {
    .categories-row {
        flex-direction: column;
        align-items: stretch;
    }
    
    .category-box {
        min-height: 120px;
        width: 100%;
    }
    
    .category-items {
        min-height: 80px;
    }
    
    .pool-item {
        font-size: 0.85rem;
        padding: 0.5rem 1rem;
    }
}

@media screen and (max-width: 480px) {
    .category-box {
        min-height: 100px;
        padding: 0.5rem;
    }
    
    .category-items {
        min-height: 60px;
        gap: 0.3rem;
    }
    
    .pool-item {
        font-size: 0.75rem;
        padding: 0.4rem 0.8rem;
    }
}

.items-pool {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
    padding: 1rem;
    background: #f0f4f8;
    border-radius: 12px;
}

.pool-item {
    padding: 0.5rem 1rem;
    background: white;
    border-radius: 20px;
    cursor: grab;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
}

.pool-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 10px rgba(0,0,0,0.15);
}

.pool-item.selected {
    background: var(--primary-color);
    color: white;
    transform: scale(1.05);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.pool-item.categorized {
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
    color: white;
    cursor: pointer;
}

.pool-item.categorized:hover {
    background: linear-gradient(135deg, #e53e3e 0%, #c53030 100%);
}

.drag-container {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.blanks-question {
    font-size: 1.1rem;
    line-height: 2;
    text-align: center;
}

.drop-zone {
    display: inline-block;
    min-width: 50px;
    padding: 0.25rem 0.5rem;
    border-bottom: 2px dashed var(--primary-color);
    text-align: center;
    color: var(--primary-color);
    cursor: pointer;
    transition: var(--transition);
    border-radius: 4px;
    margin: 0 0.25rem;
}

.drop-zone:hover {
    background: rgba(102, 126, 234, 0.1);
}

.drop-zone.filled {
    border-bottom-style: solid;
    color: var(--text-primary);
    background: rgba(102, 126, 234, 0.15);
}

.drag-choices {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
}

.drag-choice {
    padding: 0.5rem 1rem;
    background: var(--primary-color);
    color: white;
    border-radius: 20px;
    cursor: pointer;
    transition: var(--transition);
}

.drag-choice:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.drag-choice.selected {
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
    transform: scale(1.05);
}

.drag-choice.used {
    opacity: 0.4;
    cursor: not-allowed;
    transform: none;
}

.quiz-footer {
    display: flex;
    justify-content: center;
    gap: 1rem;
    padding: 1rem;
    background: var(--bg-light);
}

.quiz-btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 25px;
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    background: white;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.quiz-btn:hover:not(:disabled) {
    background: var(--bg-light);
}

.quiz-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.quiz-btn-primary {
    background: var(--primary-gradient);
    color: white;
    border: none;
}

.quiz-btn-success {
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
    color: white;
    border: none;
}

.quiz-btn-success:hover:not(:disabled) {
    background: linear-gradient(135deg, #38a169 0%, #2f855a 100%);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(56, 161, 105, 0.4);
}

.quiz-btn-primary:hover:not(:disabled) {
    background: linear-gradient(135deg, #5a67d8 0%, #6b46c1 100%);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.quiz-btn-warning:hover:not(:disabled) {
    background: linear-gradient(135deg, #dd6b20 0%, #c05621 100%);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(237, 137, 54, 0.4);
}

.quiz-btn-warning {
    background: linear-gradient(135deg, #ed8936 0%, #dd6b20 100%);
    color: white;
    border: none;
}

.quiz-score {
    font-size: 0.85rem;
    font-weight: 600;
    background: rgba(255,255,255,0.2);
    padding: 0.25rem 0.75rem;
    border-radius: 15px;
}

.practice-result {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
}

.result-card {
    background: white;
    border-radius: 20px;
    padding: 2rem;
    text-align: center;
    max-width: 350px;
    width: 100%;
    box-shadow: 0 10px 40px rgba(0,0,0,0.2);
}

.result-title {
    font-size: 1.5rem;
    color: var(--text-primary);
    margin-bottom: 1rem;
}

.result-score {
    margin: 1.5rem 0;
}

.result-score-value {
    font-size: 3rem;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.result-score-unit {
    font-size: 1.25rem;
    color: var(--text-secondary);
}

.result-message {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.result-actions {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.result-btn {
    padding: 0.875rem 1.5rem;
    border: none;
    border-radius: 25px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    color: #495057;
    box-shadow: 0 3px 10px rgba(0,0,0,0.1);
    border: 2px solid #dee2e6;
}

.result-btn:hover {
    background: linear-gradient(135deg, #e9ecef 0%, #dee2e6 100%);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.15);
}

.result-btn.result-btn-primary {
    background: var(--primary-gradient);
    color: white;
    border: none;
}

.hidden {
    display: none !important;
}

.score-wrapper {
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    padding: 70px 1rem 1rem;
    box-sizing: border-box;
    transform: translateY(-60px);
}

.score-card {
    background: rgba(255,255,255,0.95);
    border-radius: 20px;
    padding: 1.5rem;
    box-shadow: var(--shadow-lg);
    width: 100%;
    max-width: 380px;
    max-height: 100%;
    overflow-y: auto;
    animation: slideUp 0.6s ease-out;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.score-header {
    text-align: center;
    margin-bottom: 1rem;
}

.score-header h2 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
}

.score-subtitle {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-top: 0.25rem;
}

.score-visual {
    text-align: center;
    margin-bottom: 1rem;
}

.score-circle-container {
    position: relative;
    width: 140px;
    height: 140px;
    margin: 0 auto 0.75rem;
}

.score-circle-container svg {
    width: 100%;
    height: 100%;
    transform: rotate(-90deg);
}

.score-bg {
    fill: none;
    stroke: var(--border-color);
    stroke-width: 8;
}

.score-progress {
    fill: none;
    stroke: url(#scoreGradient);
    stroke-width: 8;
    stroke-linecap: round;
    stroke-dasharray: 502.65;
    stroke-dashoffset: 502.65;
    transition: stroke-dashoffset 1.5s ease;
}

.score-value {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
}

.score-value span:first-child {
    font-size: 2.25rem;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.score-unit {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-left: 0.15rem;
}

.score-grade {
    font-size: 1rem;
    font-weight: 600;
    color: var(--primary-color);
    margin-top: 0.25rem;
}

.score-details {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.detail-card {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem;
    background: var(--bg-light);
    border-radius: 10px;
}

.detail-icon {
    font-size: 1.25rem;
}

.detail-label {
    font-size: 0.65rem;
    color: var(--text-secondary);
    margin-bottom: 0.15rem;
}

.detail-value {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-primary);
}

.detail-value > span {
    margin-right: 0.5rem;
}

.detail-value > span:last-child {
    margin-right: 0;
}

.detail-score-list {
    font-size: 0.75rem;
    font-weight: 400;
    line-height: 1.5;
}

.submit-status {
    padding: 0.75rem;
    border-radius: 10px;
    text-align: center;
    font-size: 0.8rem;
    font-weight: 500;
    margin-bottom: 1rem;
    min-height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.submit-status.success {
    background: linear-gradient(135deg, #c6f6d5 0%, #9ae6b4 100%);
    color: #276749;
}

.submit-status.error {
    background: linear-gradient(135deg, #fed7d7 0%, #feb2b2 100%);
    color: #c53030;
}

.submit-status.pending {
    background: linear-gradient(135deg, #e6fffa 0%, #b2f5ea 100%);
    color: #234e52;
}

.score-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 1rem 2.5rem;
    font-size: 1rem;
    font-weight: 600;
    border: none;
    border-radius: 50px;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transition: left 0.5s;
}

.btn:hover::before {
    left: 100%;
}

.btn-glow {
    background: var(--primary-gradient);
    color: white;
    box-shadow: 0 4px 20px rgba(102, 126, 234, 0.4);
}

.btn-glow:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 30px rgba(102, 126, 234, 0.5);
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: rgba(255,255,255,0.9);
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn-secondary:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-2px);
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none !important;
}

.btn-icon {
    font-size: 1.25rem;
    transition: var(--transition);
}

.btn:hover .btn-icon {
    transform: translateX(5px);
}

.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 2000;
    transition: var(--transition);
}

.loading-overlay.hidden {
    opacity: 0;
    visibility: hidden;
}

.loading-content {
    text-align: center;
}

.loader {
    width: 60px;
    height: 60px;
    margin: 0 auto 1.5rem;
    position: relative;
}

.loader-ring {
    width: 100%;
    height: 100%;
    border: 4px solid rgba(255,255,255,0.2);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

#loading-text {
    font-size: 1rem;
    color: rgba(255,255,255,0.8);
    font-weight: 500;
}

@media screen and (max-width: 768px) {
    html {
        font-size: 18px;
    }
    
    #progress-container {
        padding: 0.5rem 1rem;
        background: linear-gradient(to bottom, rgba(0,0,0,0.95) 0%, rgba(0,0,0,0.7) 85%, transparent 100%);
    }
    
    #content {
        padding-top: 90px;
    }
    
    .stage {
        height: calc(100% - 90px);
        top: 90px;
    }
    
    #stage-cover, #stage-intro {
        margin-top: -100px;
        height: calc(100% - 90px + 100px);
    }
    
    .progress-steps {
        gap: 1rem;
    }
    
    .step-icon {
        width: 28px;
        height: 28px;
    }
    
    .step-icon svg {
        width: 16px;
        height: 16px;
    }
    
    .step-label {
        font-size: 0.65rem;
    }
    
    #cover-title {
        font-size: 2rem;
    }
    
    .cover-meta {
        font-size: 0.9rem;
        gap: 1rem;
    }
    
    .btn {
        padding: 0.875rem 2rem;
        font-size: 1rem;
    }
    
    .score-card {
        padding: 1.25rem;
        max-width: 100%;
    }
    
    .score-circle-container {
        width: 120px;
        height: 120px;
    }
    
    .score-value span:first-child {
        font-size: 2rem;
    }
    
    .score-details {
        grid-template-columns: 1fr;
        gap: 0.5rem;
    }
    
    .detail-card {
        padding: 0.65rem;
    }
    
    .score-actions {
        flex-direction: column;
        gap: 0.5rem;
    }
    
    .score-actions .btn {
        width: 100%;
        padding: 0.75rem 1.5rem;
        font-size: 0.875rem;
    }
    
    .practice-wrapper {
        padding: 1rem;
        overflow-y: auto;
        -webkit-overflow-scrolling: touch;
    }
    
    .practice-menu {
        gap: 1.5rem;
        padding: 1rem 0.5rem;
        min-height: fit-content;
        justify-content: flex-start;
    }
    
    .practice-buttons {
        gap: 1rem;
    }
}

@media screen and (max-width: 480px) {
    html {
        font-size: 20px;
    }
    
    #content {
        padding-top: 85px;
    }
    
    .stage {
        height: calc(100% - 85px);
        top: 85px;
    }
    
    #stage-cover, #stage-intro {
        margin-top: -100px;
        height: calc(100% - 85px + 100px);
    }
    
    #progress-container {
        padding: 0.4rem 0.8rem;
    }
    
    .step {
        min-width: 45px;
    }
    
    .step-icon {
        width: 24px;
        height: 24px;
    }
    
    .step-icon svg {
        width: 14px;
        height: 14px;
    }
    
    .step-label {
        font-size: 0.55rem;
    }
    
    #cover-title {
        font-size: 1.75rem;
    }
    
    .cover-info {
        padding: 1.5rem;
    }
    
    .score-card {
        max-width: 100%;
    }
    
    .score-circle-container {
        width: 130px;
        height: 130px;
    }
    
    .score-value span:first-child {
        font-size: 2rem;
    }
    
    .btn {
        padding: 0.75rem 1.5rem;
        font-size: 0.95rem;
    }
    
    .practice-wrapper {
        padding: 0.75rem;
        overflow-y: auto;
        -webkit-overflow-scrolling: touch;
    }
    
    .practice-menu {
        gap: 1rem;
        padding: 1rem 0.5rem 2rem;
        min-height: fit-content;
        justify-content: flex-start;
    }
    
    .practice-buttons {
        gap: 0.75rem;
    }
}

@media (orientation: landscape) {
    .cover-image-container {
        background: #000;
    }
    
    #cover-image {
        width: 100%;
        height: 100%;
        object-fit: contain;
    }
    
    #situation-content img,
    #situation-content video {
        width: 100%;
        height: 100%;
        object-fit: contain;
    }
    
    .cover-info {
        padding: 2rem 4rem;
    }
    
    #cover-title {
        font-size: 3rem;
    }
}

@media screen and (orientation: landscape) and (max-height: 500px) {
    #content {
        padding-top: 70px;
    }
    
    .stage {
        height: calc(100% - 70px);
        top: 70px;
    }
    
    #progress-container {
        padding: 0.35rem 1rem;
    }
    
    .progress-steps {
        gap: 0.75rem;
    }
    
    .step-icon {
        width: 24px;
        height: 24px;
    }
    
    .step-icon svg {
        width: 14px;
        height: 14px;
    }
    
    .step-label {
        font-size: 0.55rem;
    }
}

@media (hover: none) and (pointer: coarse) {
    .btn:hover {
        transform: none;
    }
    
    .btn:active {
        transform: scale(0.98);
    }
}

.feedback-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 3000;
    animation: fadeIn 0.3s ease;
}

.feedback-modal.hidden {
    display: none;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.feedback-content {
    background: white;
    border-radius: 20px;
    padding: 2rem;
    text-align: center;
    max-width: 350px;
    width: 90%;
    animation: slideUp 0.4s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.feedback-icon {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    margin: 0 auto 1rem;
}

.feedback-icon.correct {
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
    color: white;
}

.feedback-icon.wrong {
    background: linear-gradient(135deg, #f56565 0%, #e53e3e 100%);
    color: white;
}

.feedback-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.feedback-message {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 1rem;
    line-height: 1.5;
}

.feedback-score {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
}

.feedback-btn {
    padding: 0.875rem 2rem;
    border: none;
    border-radius: 25px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    background: var(--primary-gradient);
    color: white;
    transition: var(--transition);
}

.feedback-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.check-answer-btn {
    display: block;
    margin: 1.5rem auto 0;
    padding: 0.75rem 2rem;
    border: none;
    border-radius: 25px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
    color: white;
    transition: var(--transition);
}

.check-answer-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(72, 187, 120, 0.4);
}

.score-badge {
    display: inline-block;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 600;
    margin-top: 1rem;
}

.score-badge.correct {
    background: linear-gradient(135deg, #c6f6d5 0%, #9ae6b4 100%);
    color: #276749;
}

.correct-option {
    background: linear-gradient(135deg, #c6f6d5 0%, #9ae6b4 100%) !important;
    border-color: #48bb78 !important;
}

.wrong-option {
    background: linear-gradient(135deg, #fed7d7 0%, #feb2b2 100%) !important;
    border-color: #f56565 !important;
}

.correct-input {
    border-color: #48bb78 !important;
    background: #f0fff4 !important;
}

.wrong-input {
    border-color: #f56565 !important;
    background: #fff5f5 !important;
}

.sort-handle {
    margin-right: 0.75rem;
    color: #a0aec0;
    font-size: 1.2rem;
    cursor: grab;
}

.sort-item {
    display: flex;
    align-items: center;
    padding: 0.75rem 1rem;
    background: white;
    border: 2px solid var(--border-color);
    border-radius: 10px;
    margin-bottom: 0.5rem;
    cursor: grab;
    transition: var(--transition);
    user-select: none;
    -webkit-user-select: none;
}

.sort-item:active {
    cursor: grabbing;
}

.sort-item:hover {
    border-color: var(--primary-color);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.match-container {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.match-column {
    flex: 1;
}

.match-item {
    padding: 0.75rem 1rem;
    background: white;
    border: 2px solid var(--border-color);
    border-radius: 10px;
    margin-bottom: 0.5rem;
    cursor: pointer;
    transition: var(--transition);
    text-align: center;
}

.match-left.selected {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-color: #667eea;
}

.match-left.matched,
.match-right.matched {
    cursor: default;
}

.reset-match-btn {
    display: block;
    margin: 1rem auto 0;
    padding: 0.5rem 1.5rem;
    border: 1px solid var(--border-color);
    border-radius: 20px;
    background: white;
    color: var(--text-primary);
    font-size: 0.85rem;
    cursor: pointer;
    transition: var(--transition);
}

.reset-match-btn:hover {
    background: var(--bg-light);
}

.categories-row {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
}

.category-box {
    flex: 1;
    min-height: 150px;
    background: #f7fafc;
    border: 2px dashed #cbd5e0;
    border-radius: 10px;
    padding: 0.75rem;
}

.category-title {
    font-weight: 600;
    color: var(--text-primary);
    padding: 0.5rem;
    background: white;
    border-radius: 8px;
    margin-bottom: 0.5rem;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
}

.category-title:hover {
    background: var(--primary-color);
    color: white;
}

.category-items {
    min-height: 80px;
    padding: 0.5rem;
}

.items-pool {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    padding: 1rem;
    background: #edf2f7;
    border-radius: 10px;
    min-height: 60px;
}

.pool-item {
    padding: 0.5rem 1rem;
    background: white;
    border: 2px solid var(--border-color);
    border-radius: 20px;
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
}

.pool-item:hover,
.pool-item.selected {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-color: #667eea;
}

.category-items .pool-item {
    margin-bottom: 0.5rem;
}

.question-hint {
    margin-top: 1rem;
    padding: 0.75rem;
    background: #ebf8ff;
    border-radius: 8px;
    color: #2b6cb0;
    font-size: 0.85rem;
    text-align: center;
}

.question-nav {
    display: flex;
    justify-content: center;
    gap: 1rem;
    padding: 1rem;
}

.question-nav-top {
    margin-bottom: 0.5rem;
}

.question-nav-bottom {
    margin-top: 1rem;
}

.question-nav-btn {
    padding: 0.75rem 2rem;
    border: none;
    border-radius: 25px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    background: var(--primary-gradient);
    color: white;
    transition: var(--transition);
}

.question-nav-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.question-nav-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.question-nav-back {
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
}

.question-nav-back:hover:not(:disabled) {
    box-shadow: 0 4px 15px rgba(72, 187, 120, 0.4);
}

.question-explanation {
    margin-top: 2rem;
    padding: 1.5rem;
    background-color: #f8f9fa;
    border-left: 4px solid #48bb78;
    border-radius: 4px;
}

.question-explanation h4 {
    margin-top: 0;
    color: #2d3748;
    font-size: 1.1rem;
    font-weight: 600;
}

.question-explanation p {
    margin-bottom: 0;
    color: #4a5568;
    line-height: 1.6;
}

@media screen and (min-width: 1024px) {
    .quiz-content {
        padding: 1.5rem;
    }
    
    .question-container {
        max-width: 700px;
        padding: 1.5rem;
    }
    
    .question-text {
        font-size: 1.15rem;
        line-height: 1.7;
        margin-bottom: 1rem;
    }
    
    .option-item {
        padding: 0.875rem 1rem;
        border: 2px solid var(--border-color);
        border-radius: 10px;
        margin-bottom: 0.5rem;
        transition: all 0.3s ease;
    }
    
    .option-item:hover {
        border-color: var(--primary-color);
        box-shadow: 0 4px 15px rgba(102, 126, 234, 0.2);
    }
    
    .practice-btn {
        padding: 1.25rem 1.5rem;
        font-size: 1rem;
    }
    
    .quiz-header {
        padding: 0.75rem 1.5rem;
    }
    
    .quiz-footer {
        padding: 0.75rem 1.5rem;
    }
    
    .quiz-btn {
        padding: 0.75rem 1.5rem;
        font-size: 0.9rem;
    }
    
    .result-card {
        max-width: 400px;
        padding: 2rem;
    }
    
    .result-title {
        font-size: 1.5rem;
    }
    
    .result-score-value {
        font-size: 3rem;
    }
    
    .score-card {
        max-width: 400px;
        padding: 2rem;
    }
    
    .score-circle-container {
        width: 150px;
        height: 150px;
    }
    
    .score-value span:first-child {
        font-size: 2.5rem;
    }
    
    .btn {
        padding: 0.875rem 2rem;
        font-size: 1rem;
    }
    
    .sort-item {
        padding: 0.65rem 0.875rem;
        margin-bottom: 0.35rem;
    }
    
    .match-item {
        padding: 0.65rem 0.875rem;
        margin-bottom: 0.35rem;
    }
    
    .category-box {
        min-height: 120px;
        padding: 0.5rem;
    }
    
    .pool-item {
        padding: 0.4rem 0.75rem;
        font-size: 0.85rem;
    }
}

@media screen and (min-width: 1400px) {
    .question-container {
        max-width: 800px;
        padding: 1.5rem 2rem;
    }
    
    .question-text {
        font-size: 1.25rem;
    }
}

.explore-hint {
    position: fixed !important;
    top: 50% !important;
    left: 50% !important;
    transform: translate(-50%, -50%) scale(0.8) !important;
    background: linear-gradient(135deg, #10b981, #059669) !important;
    color: #fff !important;
    padding: 20px 40px !important;
    border-radius: 12px !important;
    font-weight: 700 !important;
    font-size: 1.3rem !important;
    z-index: 999999 !important;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.4) !important;
    opacity: 0;
    transition: all 0.3s ease !important;
    pointer-events: none !important;
    display: block !important;
}

.interaction-hint {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) translateY(30px) scale(0.5);
    background: linear-gradient(135deg, #10b981, #059669);
    color: #fff;
    padding: 16px 32px;
    border-radius: 30px;
    font-weight: 700;
    font-size: 1.5rem;
    z-index: 999999;
    box-shadow: 0 8px 30px rgba(16, 185, 129, 0.6);
    opacity: 0;
    transition: all 0.3s ease;
    pointer-events: none;
    display: block;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}