/* Interactive English Lesson: The Last Leaf - Main Styles */

/* ======= Base Styles ======= */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #4a6572;
    --secondary-color: #334756;
    --accent-color: #f78361;
    --text-color: #333;
    --light-text: #fff;
    --shadow-sm: 0 4px 6px rgba(0,0,0,0.05);
    --shadow-md: 0 6px 12px rgba(0,0,0,0.08);
    --shadow-lg: 0 10px 25px rgba(0,0,0,0.12);
    --card-radius: 16px;
    --input-radius: 8px;
    --transition: all 0.3s ease;
}

body {
    font-family: 'Segoe UI', 'Roboto', 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    min-height: 100vh;
    overflow-x: hidden;
    color: var(--text-color);
    line-height: 1.6;
}

/* Navigation Menu */
.nav-menu {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    padding: 15px;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.nav-items {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.nav-item {
    background-color: transparent;
    border: none;
    padding: 12px 16px;
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    border-radius: var(--input-radius);
    color: var(--secondary-color);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.nav-item::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background-color: var(--accent-color);
    transform: scaleX(0);
    transform-origin: center;
    transition: transform 0.3s ease;
}

.nav-item:hover {
    background-color: rgba(0,0,0,0.05);
}

.nav-item.active {
    color: var(--accent-color);
}

.nav-item.active::after {
    transform: scaleX(1);
}

/* Audio Control Button */
.audio-control {
    position: fixed;
    top: 80px;
    right: 20px;
    z-index: 1001;
}

.audio-btn {
    background-color: var(--accent-color);
    border: none;
    width: 45px;
    height: 45px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    color: var(--light-text);
    cursor: pointer;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.audio-btn:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-lg);
}

.audio-btn.muted {
    background-color: #888;
}

/* Achievement Popup */
.achievement-popup {
    position: fixed;
    bottom: -100px;
    left: 50%;
    transform: translateX(-50%);
    background-color: #fff;
    padding: 15px 25px;
    border-radius: var(--card-radius);
    box-shadow: var(--shadow-lg);
    z-index: 1000;
    transition: bottom 0.5s ease;
    max-width: 90%;
    width: 350px;
    text-align: center;
}

.achievement-popup.show {
    bottom: 30px;
}

.achievement-title {
    font-weight: 700;
    color: var(--accent-color);
    font-size: 18px;
    margin-bottom: 5px;
}

.achievement-desc {
    color: var(--text-color);
}

/* Main Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 100px 20px 40px;
}

/* Header */
.header {
    text-align: center;
    margin-bottom: 30px;
}

.title {
    font-size: 36px;
    font-weight: 700;
    color: var(--light-text);
    margin-bottom: 10px;
}

.subtitle {
    font-size: 18px;
    color: rgba(255,255,255,0.8);
    margin-bottom: 5px;
}

.reprint {
    font-size: 14px;
    color: rgba(255,255,255,0.6);
    font-style: italic;
}

/* Progress Container */
.progress-container {
    background-color: #fff;
    border-radius: var(--card-radius);
    padding: 15px;
    margin-bottom: 30px;
    box-shadow: var(--shadow-sm);
}

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

.progress-fill {
    height: 100%;
    background-color: var(--accent-color);
    border-radius: 5px;
    transition: width 0.4s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    color: transparent;
    font-size: 0;
}

.progress-stats {
    display: flex;
    justify-content: space-between;
    font-size: 14px;
    color: #666;
}

/* Module Containers */
.module {
    display: none;
    animation: fadeIn 0.5s ease;
}

.module.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Exercise Cards */
.exercise-card {
    background-color: #fff;
    border-radius: var(--card-radius);
    padding: 25px;
    margin-bottom: 30px;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.exercise-card:hover {
    box-shadow: var(--shadow-lg);
}

.exercise-title {
    display: flex;
    align-items: center;
    font-size: 24px;
    margin-bottom: 20px;
    color: var(--primary-color);
}

.exercise-icon {
    margin-right: 10px;
    font-size: 24px;
}

.content-block {
    margin-bottom: 20px;
}

.content-block p {
    margin-bottom: 15px;
    font-size: 16px;
}

/* Activity Styles */
.activity-title {
    font-size: 20px;
    margin-top: 30px;
    margin-bottom: 15px;
    color: var(--secondary-color);
}

.reflection-exercise {
    margin-top: 25px;
}

.reflection-exercise textarea {
    width: 100%;
    padding: 15px;
    border-radius: var(--input-radius);
    border: 1px solid #ddd;
    margin-bottom: 15px;
    font-size: 16px;
    resize: vertical;
    font-family: inherit;
}

.interactive-btn {
    background-color: var(--accent-color);
    color: #fff;
    border: none;
    padding: 12px 20px;
    border-radius: var(--input-radius);
    font-size: 16px;
    cursor: pointer;
    transition: var(--transition);
    display: inline-block;
    text-align: center;
    margin-right: 10px;
    margin-bottom: 10px;
}

.interactive-btn:hover {
    background-color: #e06747;
    transform: translateY(-2px);
}

.feedback-message {
    padding: 15px;
    margin-top: 15px;
    border-radius: var(--input-radius);
    font-size: 16px;
    opacity: 0;
    transition: var(--transition);
    max-height: 0;
    overflow: hidden;
}

.feedback-message.show {
    opacity: 1;
    max-height: 500px;
    margin-bottom: 15px;
}

.feedback-message.success {
    background-color: #e3f9e5;
    color: #1b8a2e;
}

.feedback-message.warning {
    background-color: #fef9e3;
    color: #a86b00;
}

.feedback-message.error {
    background-color: #fdecee;
    color: #d7263d;
}

.feedback-message.info {
    background-color: #e8f4fd;
    color: #1976d2;
}

/* Story Reader Styles */
.story-reader {
    background-color: #fff;
    border-radius: var(--card-radius);
    padding: 30px;
    box-shadow: var(--shadow-md);
    margin-bottom: 30px;
}

.section-title {
    font-size: 28px;
    text-align: center;
    margin-bottom: 20px;
    color: var(--primary-color);
}

.story-controls {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 30px;
    justify-content: center;
}

.reading-mode-btn {
    background-color: #f5f5f5;
    border: 1px solid #ddd;
    padding: 10px 15px;
    border-radius: var(--input-radius);
    font-size: 14px;
    cursor: pointer;
    transition: var(--transition);
}

.reading-mode-btn:hover {
    background-color: #eee;
}

.story-content p, .poem-content p {
    font-size: 18px;
    line-height: 1.8;
    margin-bottom: 20px;
}

/* Vocabulary Notes */
.vocabulary-note {
    margin: 25px 0;
    padding: 15px;
    background-color: #f9f5e7;
    border-left: 4px solid var(--accent-color);
    border-radius: 0 var(--input-radius) var(--input-radius) 0;
}

.vocabulary-note .word {
    font-weight: 700;
    margin-bottom: 5px;
    color: var(--accent-color);
}

.vocabulary-note .definition {
    color: #666;
    font-style: italic;
}

/* Vocabulary Highlights */
.highlight-vocab {
    position: relative;
    cursor: pointer;
    border-bottom: 1px dotted #ccc;
}

.highlight-vocab .vocab-tooltip {
    display: none;
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%);
    background-color: #333;
    color: #fff;
    padding: 5px 10px;
    border-radius: 4px;
    font-size: 14px;
    white-space: nowrap;
    z-index: 100;
}

.highlight-vocab:hover .vocab-tooltip {
    display: block;
}

.active-highlight {
    background-color: #ffeedd;
    border-bottom: 1px solid var(--accent-color);
}

.active-highlight .vocab-tooltip {
    display: block;
}

/* Reading Indicator */
.reading-indicator {
    display: flex;
    align-items: center;
    background-color: #333;
    color: #fff;
    padding: 10px 20px;
    border-radius: 50px;
    margin: 20px 0;
    animation: fadeIn 0.3s ease;
    justify-content: space-between;
    width: fit-content;
}

.reading-spinner {
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255,255,255,0.3);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-right: 10px;
}

.reading-indicator.fade-out {
    opacity: 0;
    transform: translateY(10px);
}

.stop-narration-btn {
    background-color: transparent;
    border: 1px solid #fff;
    color: #fff;
    padding: 5px 10px;
    border-radius: 4px;
    margin-left: 15px;
    cursor: pointer;
    transition: var(--transition);
}

.stop-narration-btn:hover {
    background-color: rgba(255,255,255,0.1);
}

/* Comprehension Check */
.comprehension-check {
    margin: 40px 0 20px;
    padding: 20px;
    background-color: #f5f5f5;
    border-radius: var(--card-radius);
    border-left: 5px solid var(--accent-color);
}

.comprehension-check h3 {
    margin-bottom: 15px;
    color: var(--primary-color);
}

.comprehension-question {
    margin-bottom: 10px;
    padding-left: 15px;
    position: relative;
}

.comprehension-question:before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--accent-color);
}

/* Story Navigation */
.story-navigation {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    border-bottom: 1px solid #eee;
    padding-bottom: 10px;
}

.story-nav-btn {
    background-color: transparent;
    border: none;
    padding: 10px 15px;
    font-size: 16px;
    cursor: pointer;
    position: relative;
    color: #666;
}

.story-nav-btn::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 0;
    width: 100%;
    height: 3px;
    background-color: var(--accent-color);
    transform: scaleX(0);
    transform-origin: center;
    transition: transform 0.3s ease;
}

.story-nav-btn:hover {
    color: var(--accent-color);
}

.story-nav-btn.active {
    color: var(--accent-color);
}

.story-nav-btn.active::after {
    transform: scaleX(1);
}

/* Question Section */
.question-section {
    animation: fadeIn 0.5s ease;
}

.section-header {
    font-size: 20px;
    color: var(--primary-color);
    margin: 25px 0 15px;
    padding-bottom: 8px;
    border-bottom: 1px solid #eee;
}

.questions-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
    margin-bottom: 30px;
}

.question-card {
    background-color: #f9f9f9;
    border-radius: var(--input-radius);
    padding: 20px;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.question-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.question-text {
    margin-bottom: 15px;
    font-size: 16px;
}

.answer-input {
    width: 100%;
    padding: 12px 15px;
    border-radius: var(--input-radius);
    border: 1px solid #ddd;
    margin-bottom: 15px;
    font-size: 16px;
    font-family: inherit;
}

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

.model-answer {
    margin-top: 10px;
    padding: 10px;
    background-color: #f5f5f5;
    border-left: 3px solid var(--accent-color);
    font-style: italic;
}

/* Vocabulary Exercise */
.vocabulary-exercise {
    margin-top: 20px;
}

.vocab-question {
    margin-bottom: 20px;
    padding: 15px;
    background-color: #f5f5f5;
    border-radius: var(--input-radius);
}

.vocab-question p {
    margin-bottom: 10px;
}

.vocab-question select {
    padding: 8px;
    border-radius: 4px;
    border: 1px solid #ddd;
    margin-left: 5px;
    cursor: pointer;
    font-size: 16px;
}

.correct-answer {
    border-color: #4caf50 !important;
    background-color: rgba(76, 175, 80, 0.1);
}

.wrong-answer {
    border-color: #f44336 !important;
    background-color: rgba(244, 67, 54, 0.1);
}

.partial-answer {
    border-color: #ff9800 !important;
    background-color: rgba(255, 152, 0, 0.1);
}

/* Matching Game */
.matching-game {
    margin-top: 20px;
}

.contraction-item {
    margin-bottom: 15px;
    padding: 10px;
    background-color: #f8f8f8;
    border-radius: var(--input-radius);
}

.contraction-input {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 16px;
    margin-top: 5px;
    font-family: inherit;
}

.show-answers-btn {
    background-color: #607d8b;
    margin-top: 10px;
    margin-left: 10px;
}

.answer-tooltip {
    position: absolute;
    background-color: #333;
    color: #fff;
    padding: 5px 10px;
    border-radius: 4px;
    font-size: 14px;
    z-index: 100;
    animation: fadeIn 0.3s ease;
}

.answer-tooltip.fade-out {
    opacity: 0;
    transform: translateY(10px);
}

/* Print Mode */
body.print-mode {
    background: #fff !important;
}

body.print-mode .nav-menu,
body.print-mode .audio-control,
body.print-mode .progress-container,
body.print-mode .story-controls,
body.print-mode .reading-indicator,
body.print-mode .feedback-message,
body.print-mode footer {
    display: none !important;
}

body.print-mode .container {
    padding: 20px;
    max-width: 100%;
}

body.print-mode .story-reader,
body.print-mode .exercise-card {
    box-shadow: none;
    padding: 0;
    margin: 20px 0;
    border-radius: 0;
}

body.print-mode .title,
body.print-mode .subtitle,
body.print-mode .reprint {
    color: #000;
}

/* Animations */
@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

/* Footer */
footer {
    text-align: center;
    padding: 20px;
    color: rgba(255,255,255,0.7);
    font-size: 14px;
}

/* Responsive Styles */
@media (max-width: 768px) {
    .container {
        padding: 90px 15px 20px;
    }
    
    .title {
        font-size: 28px;
    }
    
    .nav-items {
        gap: 10px;
    }
    
    .nav-item {
        padding: 8px 12px;
        font-size: 14px;
    }
    
    .story-content p, 
    .poem-content p {
        font-size: 16px;
    }
    
    .questions-container {
        grid-template-columns: 1fr;
    }
    
    .audio-control {
        top: 70px;
        right: 15px;
    }
    
    .audio-btn {
        width: 40px;
        height: 40px;
        font-size: 16px;
    }
}

@media (max-width: 480px) {
    .title {
        font-size: 24px;
    }
    
    .exercise-title {
        font-size: 20px;
    }
    
    .story-controls {
        flex-direction: column;
        align-items: stretch;
    }
    
    .reading-mode-btn {
        width: 100%;
        text-align: center;
    }
    
    .achievement-popup {
        width: 90%;
    }
}