/* ===== CSS Variables ===== */
:root {
    --primary-color: #4A6C6F;
    --primary-light: #5A7C7F;
    --primary-dark: #3A5C5F;
    --accent-color: #C4A16E;
    --bg-color: #F7F6F3;
    --bg-secondary: #EBEBEB;
    --text-color: #37352F;
    --text-light: #6B6B6B;
    --border-color: #E0E0E0;
    --success-color: #4CAF50;
    --warning-color: #FF9800;
    --sidebar-width: 280px;
    --header-height: 60px;
    --transition: all 0.3s ease;
    --shadow: 0 2px 10px rgba(0,0,0,0.1);
    --shadow-lg: 0 4px 20px rgba(0,0,0,0.15);
}

/* Dark Mode */
[data-theme="dark"] {
    --primary-color: #6A9C9F;
    --bg-color: #1E1E1E;
    --bg-secondary: #2D2D2D;
    --text-color: #E0E0E0;
    --text-light: #A0A0A0;
    --border-color: #404040;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.8;
    min-height: 100vh;
}

/* ===== Sidebar ===== */
.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    width: var(--sidebar-width);
    height: 100vh;
    background: linear-gradient(180deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: white;
    display: flex;
    flex-direction: column;
    z-index: 1000;
    transition: var(--transition);
}

.sidebar-header {
    padding: 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-icon {
    font-size: 28px;
}

.logo-text {
    font-size: 16px;
    font-weight: 600;
}

.sidebar-close {
    display: none;
    background: none;
    border: none;
    color: white;
    font-size: 28px;
    cursor: pointer;
}

/* Progress Section */
.progress-section {
    padding: 20px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.progress-label {
    display: flex;
    justify-content: space-between;
    font-size: 14px;
    margin-bottom: 8px;
    opacity: 0.9;
}

.progress-bar {
    height: 8px;
    background: rgba(255,255,255,0.2);
    border-radius: 4px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--accent-color);
    border-radius: 4px;
    transition: width 0.5s ease;
    width: 0%;
}

/* Navigation Menu */
.nav-menu {
    flex: 1;
    overflow-y: auto;
    padding: 10px 0;
}

.nav-item {
    display: flex;
    align-items: center;
    padding: 12px 20px;
    color: rgba(255,255,255,0.8);
    text-decoration: none;
    font-size: 14px;
    cursor: pointer;
    transition: var(--transition);
    gap: 10px;
}

.nav-item:hover {
    background: rgba(255,255,255,0.1);
    color: white;
}

.nav-item.active {
    background: rgba(255,255,255,0.15);
    color: white;
    border-left: 3px solid var(--accent-color);
}

.nav-item.completed::before {
    content: '✓';
    color: var(--success-color);
    font-weight: bold;
}

.nav-chapter-num {
    width: 24px;
    height: 24px;
    background: rgba(255,255,255,0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    flex-shrink: 0;
}

.nav-item.completed .nav-chapter-num {
    background: var(--success-color);
}

/* Sidebar Footer */
.sidebar-footer {
    padding: 15px 20px;
    border-top: 1px solid rgba(255,255,255,0.1);
}

.theme-toggle {
    display: flex;
    align-items: center;
    gap: 10px;
    width: 100%;
    padding: 10px 15px;
    background: rgba(255,255,255,0.1);
    border: none;
    border-radius: 8px;
    color: white;
    font-size: 14px;
    cursor: pointer;
    transition: var(--transition);
}

.theme-toggle:hover {
    background: rgba(255,255,255,0.2);
}

/* ===== Main Content ===== */
.main-content {
    margin-left: var(--sidebar-width);
    min-height: 100vh;
    transition: var(--transition);
}

/* Top Bar */
.top-bar {
    position: sticky;
    top: 0;
    height: var(--header-height);
    background: var(--bg-color);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    padding: 0 30px;
    gap: 20px;
    z-index: 100;
}

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.menu-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text-color);
    transition: var(--transition);
}

.search-box {
    flex: 1;
    max-width: 500px;
    display: flex;
    gap: 10px;
}

.search-box input {
    flex: 1;
    padding: 10px 15px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 14px;
    background: var(--bg-secondary);
    color: var(--text-color);
    transition: var(--transition);
}

.search-box input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(74, 108, 111, 0.1);
}

.search-btn {
    padding: 10px 15px;
    background: var(--primary-color);
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: var(--transition);
}

.search-btn:hover {
    background: var(--primary-dark);
}

/* ===== Home Section ===== */
.home-section {
    padding: 40px;
    max-width: 1200px;
    margin: 0 auto;
}

.hero {
    display: flex;
    gap: 40px;
    align-items: center;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    padding: 40px;
    border-radius: 16px;
    color: white;
    margin-bottom: 40px;
    box-shadow: var(--shadow-lg);
}

.hero-cover {
    width: 200px;
    height: auto;
    border-radius: 8px;
    box-shadow: var(--shadow-lg);
}

.hero-content h1 {
    font-size: 2rem;
    margin-bottom: 10px;
}

.hero-subtitle {
    font-size: 1.1rem;
    opacity: 0.9;
    margin-bottom: 5px;
}

.hero-author {
    opacity: 0.8;
    margin-bottom: 20px;
}

.btn-primary {
    padding: 12px 30px;
    background: var(--accent-color);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

/* Features */
.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
}

.feature-card {
    background: white;
    padding: 25px;
    border-radius: 12px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

[data-theme="dark"] .feature-card {
    background: var(--bg-secondary);
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    font-size: 40px;
    display: block;
    margin-bottom: 15px;
}

.feature-card h3 {
    color: var(--primary-color);
    margin-bottom: 8px;
}

.feature-card p {
    color: var(--text-light);
    font-size: 14px;
}

/* Chapter Grid */
.chapter-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.chapter-card {
    background: white;
    border-radius: 12px;
    padding: 20px;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: var(--shadow);
    border-left: 4px solid var(--primary-color);
}

[data-theme="dark"] .chapter-card {
    background: var(--bg-secondary);
}

.chapter-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.chapter-card.completed {
    border-left-color: var(--success-color);
}

.chapter-card-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 10px;
}

.chapter-num {
    width: 36px;
    height: 36px;
    background: var(--primary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 14px;
}

.chapter-card.completed .chapter-num {
    background: var(--success-color);
}

.chapter-card.completed .chapter-num::after {
    content: '✓';
}

.chapter-card.completed .chapter-num span {
    display: none;
}

.chapter-card h3 {
    flex: 1;
    font-size: 15px;
    color: var(--text-color);
}

.chapter-card p {
    color: var(--text-light);
    font-size: 13px;
    line-height: 1.6;
}

/* ===== Chapter Section ===== */
.chapter-section {
    padding: 30px 40px;
    max-width: 900px;
    margin: 0 auto;
}

.chapter-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
}

.btn-back {
    padding: 8px 16px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: var(--text-color);
    cursor: pointer;
    transition: var(--transition);
}

.btn-back:hover {
    background: var(--border-color);
}

.chapter-nav {
    display: flex;
    gap: 10px;
}

.btn-nav {
    padding: 8px 16px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: var(--text-color);
    cursor: pointer;
    transition: var(--transition);
}

.btn-nav:hover:not(:disabled) {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

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

/* Chapter Content Styling */
.chapter-content {
    background: white;
    padding: 40px;
    border-radius: 12px;
    box-shadow: var(--shadow);
    margin-bottom: 30px;
}

[data-theme="dark"] .chapter-content {
    background: var(--bg-secondary);
}

.chapter-content h1 {
    color: var(--primary-color);
    font-size: 1.8em;
    font-weight: 700;
    border-bottom: 3px solid var(--primary-color);
    padding-bottom: 15px;
    margin: 0 0 30px 0;
}

.chapter-content h2 {
    color: var(--primary-color);
    font-size: 1.4em;
    font-weight: 600;
    margin: 30px 0 20px 0;
}

.chapter-content h3 {
    color: var(--primary-color);
    font-size: 1.2em;
    font-weight: 600;
    margin: 25px 0 15px 0;
}

.chapter-content p {
    margin: 12px 0;
    text-align: justify;
}

.chapter-content ul, 
.chapter-content ol {
    margin: 15px 0;
    padding-left: 30px;
}

.chapter-content li {
    margin: 8px 0;
}

.chapter-content blockquote {
    background-color: var(--bg-secondary);
    padding: 15px 20px;
    border-radius: 6px;
    border-left: 4px solid var(--primary-color);
    margin: 20px 0;
    font-style: italic;
}

.chapter-content code {
    background-color: #F0E5DE;
    padding: 2px 6px;
    border-radius: 3px;
    font-family: 'Courier New', monospace;
    font-size: 0.9em;
}

[data-theme="dark"] .chapter-content code {
    background-color: #3D3D3D;
}

.chapter-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
}

.chapter-content th, 
.chapter-content td {
    padding: 12px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.chapter-content th {
    background-color: var(--bg-secondary);
    color: var(--primary-color);
    font-weight: 600;
}

.chapter-content hr {
    border: none;
    border-top: 1px solid var(--border-color);
    margin: 30px 0;
}

/* Special Boxes */
.chapter-content .tip-box {
    background-color: #F0E5DE;
    padding: 20px;
    border-left: 5px solid var(--accent-color);
    margin: 25px 0;
    border-radius: 4px;
}

[data-theme="dark"] .chapter-content .tip-box {
    background-color: #3D3530;
}

.chapter-content .solution-box {
    background-color: #E4E9E4;
    padding: 20px;
    border-radius: 12px;
    margin: 25px 0;
}

[data-theme="dark"] .chapter-content .solution-box {
    background-color: #2D3D2D;
}

.chapter-content .code-box {
    background-color: #2E3235;
    color: #E0E0E0;
    padding: 20px;
    border-radius: 8px;
    margin: 25px 0;
    overflow-x: auto;
}

.chapter-content .code-box pre {
    margin: 0;
    font-family: 'Courier New', monospace;
    font-size: 0.9em;
    white-space: pre-wrap;
    word-wrap: break-word;
}

/* Chapter Footer */
.chapter-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
    background: white;
    border-radius: 12px;
    box-shadow: var(--shadow);
}

[data-theme="dark"] .chapter-footer {
    background: var(--bg-secondary);
}

.complete-check {
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    font-size: 15px;
}

.complete-check input {
    display: none;
}

.checkmark {
    width: 24px;
    height: 24px;
    border: 2px solid var(--primary-color);
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.complete-check input:checked + .checkmark {
    background: var(--success-color);
    border-color: var(--success-color);
}

.complete-check input:checked + .checkmark::after {
    content: '✓';
    color: white;
    font-weight: bold;
}

/* ===== Search Section ===== */
.search-section {
    padding: 40px;
    max-width: 900px;
    margin: 0 auto;
}

.search-section h2 {
    color: var(--primary-color);
    margin-bottom: 20px;
}

.search-result-item {
    background: white;
    padding: 20px;
    border-radius: 8px;
    margin-bottom: 15px;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: var(--shadow);
}

[data-theme="dark"] .search-result-item {
    background: var(--bg-secondary);
}

.search-result-item:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow-lg);
}

.search-result-item h4 {
    color: var(--primary-color);
    margin-bottom: 8px;
}

.search-result-item p {
    color: var(--text-light);
    font-size: 14px;
}

.search-result-item mark {
    background: #FFEB3B;
    padding: 0 2px;
    border-radius: 2px;
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
    .sidebar {
        transform: translateX(-100%);
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
    
    .sidebar-close {
        display: block;
    }
    
    .main-content {
        margin-left: 0;
    }
    
    .menu-toggle {
        display: flex;
    }
    
    .hero {
        flex-direction: column;
        text-align: center;
    }
    
    .hero-cover {
        width: 150px;
    }
}

@media (max-width: 768px) {
    .home-section,
    .chapter-section,
    .search-section {
        padding: 20px;
    }
    
    .hero {
        padding: 25px;
    }
    
    .hero-content h1 {
        font-size: 1.5rem;
    }
    
    .chapter-content {
        padding: 25px;
    }
    
    .chapter-footer {
        flex-direction: column;
        gap: 20px;
    }
    
    .chapter-header {
        flex-direction: column;
        gap: 15px;
    }
    
    .features {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .features {
        grid-template-columns: 1fr;
    }
    
    .chapter-grid {
        grid-template-columns: 1fr;
    }
    
    .top-bar {
        padding: 0 15px;
    }
    
    .search-box {
        max-width: none;
    }
}

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

.chapter-content {
    animation: fadeIn 0.3s ease;
}

/* ===== Scrollbar ===== */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-dark);
}

/* ===== Feedback System ===== */

/* Floating Action Button */
.feedback-fab {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    border: none;
    font-size: 28px;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(74, 108, 111, 0.4);
    transition: var(--transition);
    z-index: 9999;
    display: flex;
    align-items: center;
    justify-content: center;
    pointer-events: auto !important;
}

.feedback-fab:hover {
    transform: scale(1.1);
    box-shadow: 0 6px 20px rgba(74, 108, 111, 0.5);
}

.feedback-fab:active {
    transform: scale(0.95);
}

/* Feedback List Button in Sidebar */
.feedback-list-btn {
    display: flex;
    align-items: center;
    gap: 10px;
    width: 100%;
    padding: 10px 15px;
    background: rgba(255,255,255,0.1);
    border: none;
    border-radius: 8px;
    color: white;
    font-size: 14px;
    cursor: pointer;
    transition: var(--transition);
    margin-bottom: 10px;
}

.feedback-list-btn:hover {
    background: rgba(255,255,255,0.2);
}

.feedback-count {
    margin-left: auto;
    background: var(--accent-color);
    padding: 2px 8px;
    border-radius: 10px;
    font-size: 12px;
    font-weight: 600;
}

/* Modal Overlay */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    padding: 20px;
    backdrop-filter: blur(4px);
}

.modal-overlay.active {
    display: flex;
}

.modal-content {
    background: var(--bg-color);
    border-radius: 16px;
    width: 100%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
    animation: modalSlideIn 0.3s ease;
}

.modal-content.modal-large {
    max-width: 800px;
}

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

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 25px;
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    background: var(--bg-color);
    z-index: 10;
}

.modal-header h2 {
    font-size: 1.3rem;
    color: var(--primary-color);
    margin: 0;
}

.modal-close {
    width: 36px;
    height: 36px;
    border: none;
    background: var(--bg-secondary);
    border-radius: 50%;
    font-size: 24px;
    cursor: pointer;
    color: var(--text-light);
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-close:hover {
    background: var(--border-color);
    color: var(--text-color);
}

/* Form Styles */
#feedbackForm {
    padding: 25px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-weight: 500;
    margin-bottom: 8px;
    color: var(--text-color);
}

.form-group .required {
    color: #e74c3c;
}

.form-group input[type="text"],
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 14px;
    background: var(--bg-secondary);
    color: var(--text-color);
    transition: var(--transition);
    font-family: inherit;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(74, 108, 111, 0.1);
}

.form-group input[readonly] {
    background: var(--border-color);
    cursor: not-allowed;
}

.form-group small {
    display: block;
    margin-top: 6px;
    color: var(--text-light);
    font-size: 12px;
}

/* Priority Buttons */
.priority-buttons {
    display: flex;
    gap: 10px;
}

.priority-btn {
    flex: 1;
    cursor: pointer;
}

.priority-btn input {
    display: none;
}

.priority-btn span {
    display: block;
    padding: 10px;
    text-align: center;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    transition: var(--transition);
    font-size: 14px;
}

.priority-btn input:checked + span {
    border-color: var(--primary-color);
    background: rgba(74, 108, 111, 0.1);
}

.priority-btn:hover span {
    border-color: var(--primary-light);
}

/* Form Actions */
.form-actions {
    display: flex;
    gap: 12px;
    justify-content: flex-end;
    margin-top: 25px;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
}

.btn-secondary {
    padding: 12px 24px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-color);
    font-size: 14px;
    cursor: pointer;
    transition: var(--transition);
}

.btn-secondary:hover {
    background: var(--border-color);
}

/* Feedback List Controls */
.feedback-list-controls {
    display: flex;
    gap: 10px;
    padding: 15px 25px;
    border-bottom: 1px solid var(--border-color);
    flex-wrap: wrap;
}

.feedback-list-controls select {
    padding: 8px 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background: var(--bg-secondary);
    color: var(--text-color);
    font-size: 13px;
}

.btn-export {
    padding: 8px 16px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 13px;
    transition: var(--transition);
    margin-left: auto;
}

.btn-export:hover {
    background: var(--primary-dark);
}

.btn-json {
    background: #27ae60;
}

.btn-json:hover {
    background: #219a52;
}

.btn-import {
    background: #3498db;
    cursor: pointer;
}

.btn-import:hover {
    background: #2980b9;
}

/* Feedback List */
.feedback-list {
    padding: 15px 25px;
    max-height: 400px;
    overflow-y: auto;
}

.feedback-item {
    background: var(--bg-secondary);
    border-radius: 10px;
    padding: 15px;
    margin-bottom: 12px;
    border-left: 4px solid var(--primary-color);
}

.feedback-item.priority-high {
    border-left-color: #e74c3c;
}

.feedback-item.priority-low {
    border-left-color: #27ae60;
}

.feedback-item-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 10px;
    flex-wrap: wrap;
    gap: 8px;
}

.feedback-item-meta {
    display: flex;
    gap: 10px;
    align-items: center;
    flex-wrap: wrap;
}

.feedback-type-badge {
    padding: 3px 10px;
    background: var(--primary-color);
    color: white;
    border-radius: 12px;
    font-size: 11px;
}

.feedback-chapter {
    color: var(--text-light);
    font-size: 12px;
}

.feedback-reader {
    font-weight: 500;
    color: var(--text-color);
}

.feedback-date {
    color: var(--text-light);
    font-size: 12px;
}

.feedback-selected-text {
    background: rgba(255, 235, 59, 0.2);
    padding: 8px 12px;
    border-radius: 6px;
    font-size: 13px;
    margin-bottom: 10px;
    border-left: 3px solid #FFC107;
}

.feedback-content {
    color: var(--text-color);
    line-height: 1.6;
}

.feedback-delete {
    background: none;
    border: none;
    color: var(--text-light);
    cursor: pointer;
    padding: 5px;
    font-size: 16px;
    transition: var(--transition);
}

.feedback-delete:hover {
    color: #e74c3c;
}

/* Feedback Stats */
.feedback-stats {
    padding: 15px 25px;
    border-top: 1px solid var(--border-color);
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    background: var(--bg-secondary);
    border-radius: 0 0 16px 16px;
}

.stat-item {
    text-align: center;
}

.stat-value {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-color);
}

.stat-label {
    font-size: 12px;
    color: var(--text-light);
}

/* Empty State */
.feedback-empty {
    text-align: center;
    padding: 40px;
    color: var(--text-light);
}

.feedback-empty-icon {
    font-size: 48px;
    margin-bottom: 15px;
}

/* Toast Notification */
.toast {
    position: fixed;
    bottom: 100px;
    right: 30px;
    background: var(--text-color);
    color: var(--bg-color);
    padding: 15px 25px;
    border-radius: 10px;
    box-shadow: var(--shadow-lg);
    transform: translateY(100px);
    opacity: 0;
    transition: all 0.3s ease;
    z-index: 3000;
    max-width: 300px;
}

.toast.show {
    transform: translateY(0);
    opacity: 1;
}

.toast.success {
    background: #27ae60;
    color: white;
}

.toast.error {
    background: #e74c3c;
    color: white;
}

/* Text Selection Highlight */
.chapter-content ::selection {
    background: rgba(74, 108, 111, 0.3);
}

/* Responsive */
@media (max-width: 768px) {
    .feedback-fab {
        bottom: 20px;
        right: 20px;
        width: 50px;
        height: 50px;
        font-size: 24px;
    }
    
    .modal-content {
        margin: 10px;
        max-height: 95vh;
    }
    
    .priority-buttons {
        flex-direction: column;
    }
    
    .feedback-list-controls {
        flex-direction: column;
    }
    
    .btn-export {
        margin-left: 0;
        width: 100%;
    }
}

/* ===== Practice Section ===== */

/* Practice Button in Sidebar */
.practice-btn {
    display: flex;
    align-items: center;
    gap: 10px;
    width: 100%;
    padding: 12px 15px;
    background: linear-gradient(135deg, var(--accent-color) 0%, #D4B17E 100%);
    border: none;
    border-radius: 8px;
    color: white;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    margin-bottom: 10px;
}

.practice-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(196, 161, 110, 0.4);
}

/* Practice Banner on Home */
.practice-banner {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 16px;
    padding: 25px 30px;
    margin-bottom: 30px;
    box-shadow: var(--shadow-lg);
}

.practice-banner-content {
    display: flex;
    align-items: center;
    gap: 20px;
}

.practice-banner-icon {
    font-size: 48px;
    flex-shrink: 0;
}

.practice-banner-text {
    flex: 1;
    color: white;
}

.practice-banner-text h3 {
    font-size: 1.3rem;
    margin-bottom: 5px;
}

.practice-banner-text p {
    opacity: 0.9;
    font-size: 14px;
}

.practice-banner .btn-primary {
    background: white;
    color: #667eea;
    flex-shrink: 0;
}

.practice-banner .btn-primary:hover {
    background: #f0f0f0;
}

/* Practice Section */
.practice-section {
    padding: 30px 40px;
    max-width: 1200px;
    margin: 0 auto;
}

.practice-header {
    display: flex;
    align-items: center;
    gap: 20px;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
}

.practice-header h2 {
    color: var(--primary-color);
    font-size: 1.5rem;
    margin: 0;
}

/* Practice Categories Grid */
.practice-categories {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.practice-category-card {
    background: white;
    border-radius: 16px;
    padding: 25px;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: var(--shadow);
    border: 2px solid transparent;
    text-align: center;
}

[data-theme="dark"] .practice-category-card {
    background: var(--bg-secondary);
}

.practice-category-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.category-icon {
    font-size: 48px;
    display: block;
    margin-bottom: 15px;
}

.practice-category-card h3 {
    color: var(--primary-color);
    margin-bottom: 10px;
    font-size: 1.1rem;
}

.practice-category-card p {
    color: var(--text-light);
    font-size: 14px;
    margin-bottom: 15px;
}

.category-progress {
    padding-top: 15px;
    border-top: 1px solid var(--border-color);
}

.progress-text {
    font-size: 13px;
    color: var(--primary-color);
    font-weight: 600;
}

/* Practice Detail */
.practice-detail {
    animation: fadeIn 0.3s ease;
}

.practice-content {
    background: white;
    border-radius: 16px;
    padding: 30px;
    margin-top: 20px;
    box-shadow: var(--shadow);
}

[data-theme="dark"] .practice-content {
    background: var(--bg-secondary);
}

/* Lesson Cards */
.lesson-list {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.lesson-card {
    background: var(--bg-secondary);
    border-radius: 12px;
    padding: 20px;
    cursor: pointer;
    transition: var(--transition);
    border-left: 4px solid var(--primary-color);
}

[data-theme="dark"] .lesson-card {
    background: #2a2a2a;
}

.lesson-card:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow);
}

.lesson-card.completed {
    border-left-color: var(--success-color);
}

.lesson-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}

.lesson-card h4 {
    color: var(--text-color);
    font-size: 1rem;
    margin: 0;
}

.lesson-status {
    font-size: 20px;
}

.lesson-card p {
    color: var(--text-light);
    font-size: 14px;
    margin: 0;
}

/* Lesson Detail View */
.lesson-detail {
    animation: fadeIn 0.3s ease;
}

.lesson-detail h3 {
    color: var(--primary-color);
    font-size: 1.3rem;
    margin-bottom: 20px;
}

.mission-box {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 20px;
    border-radius: 12px;
    margin-bottom: 25px;
    text-align: center;
}

.mission-box h4 {
    font-size: 14px;
    opacity: 0.9;
    margin-bottom: 8px;
}

.mission-box p {
    font-size: 1.1rem;
    font-weight: 600;
    margin: 0;
}

/* Steps */
.steps-section {
    margin-bottom: 25px;
}

.steps-section h4 {
    color: var(--text-color);
    margin-bottom: 15px;
    font-size: 1rem;
}

.step-item {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 12px 15px;
    background: var(--bg-secondary);
    border-radius: 8px;
    margin-bottom: 10px;
    transition: var(--transition);
}

[data-theme="dark"] .step-item {
    background: #2a2a2a;
}

.step-checkbox {
    width: 24px;
    height: 24px;
    border: 2px solid var(--primary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    flex-shrink: 0;
    transition: var(--transition);
}

.step-checkbox.checked {
    background: var(--success-color);
    border-color: var(--success-color);
}

.step-checkbox.checked::after {
    content: '✓';
    color: white;
    font-size: 14px;
}

.step-text {
    flex: 1;
    color: var(--text-color);
    line-height: 1.5;
}

.step-item.completed .step-text {
    text-decoration: line-through;
    opacity: 0.6;
}

/* Code Examples */
.code-example {
    background: #2E3235;
    color: #E0E0E0;
    padding: 20px;
    border-radius: 10px;
    margin: 15px 0;
    overflow-x: auto;
    font-family: 'Courier New', monospace;
    font-size: 14px;
    line-height: 1.6;
}

.code-example pre {
    margin: 0;
    white-space: pre-wrap;
}

.code-label {
    font-size: 12px;
    color: var(--text-light);
    margin-bottom: 8px;
    font-weight: 600;
}

/* Before/After */
.before-after {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
    margin: 20px 0;
}

.before-box, .after-box {
    padding: 15px;
    border-radius: 10px;
}

.before-box {
    background: #ffebee;
    border: 1px solid #ffcdd2;
}

.after-box {
    background: #e8f5e9;
    border: 1px solid #c8e6c9;
}

[data-theme="dark"] .before-box {
    background: #3d2a2a;
    border-color: #5d3a3a;
}

[data-theme="dark"] .after-box {
    background: #2a3d2a;
    border-color: #3a5d3a;
}

.before-box h5, .after-box h5 {
    font-size: 12px;
    margin-bottom: 10px;
    color: var(--text-light);
}

.before-box code, .after-box code {
    display: block;
    font-family: 'Courier New', monospace;
    font-size: 13px;
}

/* Checkpoints */
.checkpoints-section {
    background: var(--bg-secondary);
    padding: 20px;
    border-radius: 12px;
    margin-top: 25px;
}

[data-theme="dark"] .checkpoints-section {
    background: #2a2a2a;
}

.checkpoints-section h4 {
    color: var(--primary-color);
    margin-bottom: 15px;
    font-size: 1rem;
}

.checkpoint-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 0;
    border-bottom: 1px solid var(--border-color);
}

.checkpoint-item:last-child {
    border-bottom: none;
}

.checkpoint-icon {
    font-size: 18px;
}

/* Discovery Box */
.discovery-box {
    background: linear-gradient(135deg, #fff3e0 0%, #ffe0b2 100%);
    border-left: 4px solid var(--accent-color);
    padding: 20px;
    border-radius: 0 12px 12px 0;
    margin: 20px 0;
}

[data-theme="dark"] .discovery-box {
    background: linear-gradient(135deg, #3d3530 0%, #4d4540 100%);
}

.discovery-box h5 {
    color: var(--accent-color);
    margin-bottom: 10px;
    font-size: 14px;
}

.discovery-box pre {
    margin: 0;
    font-family: 'Courier New', monospace;
    font-size: 13px;
    white-space: pre-wrap;
    color: var(--text-color);
}

/* Insight Box */
.insight-box {
    background: linear-gradient(135deg, #e3f2fd 0%, #bbdefb 100%);
    border-left: 4px solid #2196F3;
    padding: 20px;
    border-radius: 0 12px 12px 0;
    margin: 20px 0;
}

[data-theme="dark"] .insight-box {
    background: linear-gradient(135deg, #1a3a5c 0%, #2a4a6c 100%);
}

.insight-box h5 {
    color: #2196F3;
    margin-bottom: 10px;
    font-size: 14px;
}

.insight-box p {
    margin: 0;
    color: var(--text-color);
    line-height: 1.6;
}

/* Templates Section */
.template-card {
    background: var(--bg-secondary);
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 20px;
}

[data-theme="dark"] .template-card {
    background: #2a2a2a;
}

.template-card h4 {
    color: var(--primary-color);
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.copy-btn {
    padding: 8px 16px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 13px;
    transition: var(--transition);
}

.copy-btn:hover {
    background: var(--primary-dark);
}

.copy-btn.copied {
    background: var(--success-color);
}

/* Shortcuts Table */
.shortcuts-table {
    width: 100%;
    border-collapse: collapse;
}

.shortcuts-table th,
.shortcuts-table td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.shortcuts-table th {
    background: var(--bg-secondary);
    color: var(--primary-color);
    font-weight: 600;
}

.shortcuts-table kbd {
    background: #2E3235;
    color: #E0E0E0;
    padding: 4px 8px;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    font-size: 13px;
}

/* Troubleshooting */
.troubleshooting-item {
    background: var(--bg-secondary);
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 15px;
}

[data-theme="dark"] .troubleshooting-item {
    background: #2a2a2a;
}

.troubleshooting-item h4 {
    color: #e74c3c;
    margin-bottom: 10px;
    font-size: 1rem;
}

.troubleshooting-item .cause {
    color: var(--text-light);
    font-size: 13px;
    margin-bottom: 10px;
}

.troubleshooting-item .solution {
    background: #e8f5e9;
    color: #2e7d32;
    padding: 10px 15px;
    border-radius: 8px;
    font-weight: 500;
}

[data-theme="dark"] .troubleshooting-item .solution {
    background: #2a3d2a;
    color: #81c784;
}

/* Complete Guide Parts */
.guide-part {
    margin-bottom: 30px;
}

.guide-part h4 {
    color: var(--primary-color);
    font-size: 1.1rem;
    margin-bottom: 10px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--primary-color);
}

.part-subtitle {
    color: var(--text-light);
    font-size: 14px;
    margin-bottom: 15px;
}

.guide-chapter-card {
    background: var(--bg-secondary);
    border-radius: 12px;
    margin-bottom: 12px;
    overflow: hidden;
    transition: var(--transition);
    border: 2px solid transparent;
}

[data-theme="dark"] .guide-chapter-card {
    background: #2a2a2a;
}

.guide-chapter-card:hover {
    border-color: var(--primary-color);
}

.guide-chapter-card.expanded {
    border-color: var(--primary-color);
    box-shadow: var(--shadow);
}

.guide-chapter-header {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 15px 20px;
    cursor: pointer;
    transition: var(--transition);
}

.guide-chapter-header:hover {
    background: rgba(0,0,0,0.03);
}

[data-theme="dark"] .guide-chapter-header:hover {
    background: rgba(255,255,255,0.03);
}

.expand-icon {
    margin-left: auto;
    color: var(--text-light);
    font-size: 12px;
    transition: var(--transition);
}

.guide-chapter {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 12px 15px;
    background: var(--bg-secondary);
    border-radius: 8px;
    margin-bottom: 10px;
}

[data-theme="dark"] .guide-chapter {
    background: #2a2a2a;
}

.chapter-number {
    width: 32px;
    height: 32px;
    background: var(--primary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 14px;
    flex-shrink: 0;
}

.chapter-info h5 {
    color: var(--text-color);
    margin-bottom: 3px;
    font-size: 14px;
}

.chapter-info p {
    color: var(--text-light);
    font-size: 12px;
    margin: 0;
}

/* Chapter Example (Expandable) */
.chapter-example {
    padding: 20px;
    border-top: 1px solid var(--border-color);
    background: rgba(0,0,0,0.02);
    animation: fadeIn 0.3s ease;
}

[data-theme="dark"] .chapter-example {
    background: rgba(255,255,255,0.02);
}

.example-title {
    color: var(--primary-color);
    font-weight: 600;
    font-size: 15px;
    margin-bottom: 15px;
}

.example-notes {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.example-note {
    border-left: 3px solid var(--primary-color);
    padding-left: 15px;
}

.note-date {
    font-weight: 600;
    color: var(--text-color);
    font-size: 13px;
    margin-bottom: 5px;
}

.example-records {
    background: var(--bg-secondary);
    padding: 15px 20px;
    border-radius: 10px;
    margin: 15px 0;
}

[data-theme="dark"] .example-records {
    background: #333;
}

.example-records h5 {
    color: var(--primary-color);
    margin-bottom: 10px;
    font-size: 14px;
}

.example-records ul {
    margin: 0;
    padding-left: 20px;
}

.example-records li {
    color: var(--text-color);
    font-size: 13px;
    line-height: 1.8;
}

/* Timeline */
.example-timeline {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin: 15px 0;
}

.timeline-item {
    display: flex;
    align-items: flex-start;
    gap: 15px;
    padding: 12px 15px;
    background: var(--bg-secondary);
    border-radius: 8px;
    border-left: 3px solid var(--primary-color);
}

[data-theme="dark"] .timeline-item {
    background: #333;
}

.timeline-month {
    font-weight: 700;
    color: var(--primary-color);
    min-width: 50px;
    font-size: 14px;
}

.timeline-content {
    color: var(--text-color);
    font-size: 14px;
    line-height: 1.5;
}

/* Complete Button */
.complete-lesson-btn {
    display: block;
    width: 100%;
    padding: 15px;
    background: var(--success-color);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    margin-top: 25px;
    transition: var(--transition);
}

.complete-lesson-btn:hover {
    background: #43a047;
    transform: translateY(-2px);
}

.complete-lesson-btn.completed {
    background: var(--text-light);
    cursor: default;
}

/* Responsive */
@media (max-width: 768px) {
    .practice-section {
        padding: 20px;
    }
    
    .practice-banner-content {
        flex-direction: column;
        text-align: center;
    }
    
    .practice-banner .btn-primary {
        width: 100%;
    }
    
    .practice-categories {
        grid-template-columns: 1fr;
    }
    
    .before-after {
        grid-template-columns: 1fr;
    }
    
    .practice-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }
    
    .weeks-grid {
        grid-template-columns: 1fr;
    }
}

/* ===== 6주 실습 과정 ===== */
.practice-category-card.featured {
    border: 2px solid var(--primary-color);
    position: relative;
}

.category-badge {
    position: absolute;
    top: 10px;
    right: 10px;
    background: var(--primary-color);
    color: white;
    padding: 3px 10px;
    border-radius: 12px;
    font-size: 11px;
    font-weight: 700;
}

.weeks-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.week-card-practice {
    background: var(--bg-secondary);
    border-radius: 16px;
    padding: 25px;
    border: 2px solid transparent;
    transition: var(--transition);
    position: relative;
}

[data-theme="dark"] .week-card-practice {
    background: #2a2a2a;
}

.week-card-practice:hover {
    border-color: var(--primary-color);
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}

.week-card-practice .week-badge {
    display: inline-block;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 700;
    margin-bottom: 12px;
}

.week-card-practice h4 {
    color: var(--text-color);
    font-size: 1.2rem;
    margin-bottom: 8px;
}

.week-card-practice .week-subtitle {
    color: var(--text-light);
    font-size: 14px;
    margin-bottom: 15px;
}

.week-card-practice .week-topics {
    list-style: none;
    padding: 0;
    margin: 0 0 20px 0;
}

.week-card-practice .week-topics li {
    color: var(--text-color);
    font-size: 13px;
    padding: 6px 0;
    padding-left: 20px;
    position: relative;
}

.week-card-practice .week-topics li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--success-color);
    font-weight: 700;
}

.btn-week-start {
    display: inline-block;
    padding: 10px 20px;
    background: var(--primary-color);
    color: white;
    border-radius: 8px;
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
    transition: var(--transition);
}

.btn-week-start:hover {
    background: var(--primary-dark);
    transform: translateX(3px);
}

/* ===== 실습 연습장 ===== */
.practice-exercise {
    margin-top: 50px;
    padding: 30px;
    background: linear-gradient(135deg, #f0f9f4 0%, #e8f5e9 100%);
    border-radius: 16px;
    border: 2px solid var(--primary-color);
}

[data-theme="dark"] .practice-exercise {
    background: linear-gradient(135deg, #1a2f23 0%, #1e3a2f 100%);
}

.practice-exercise h3 {
    color: var(--primary-color);
    font-size: 1.4rem;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.exercise-mission {
    background: white;
    padding: 15px 20px;
    border-radius: 10px;
    margin-bottom: 20px;
    border-left: 4px solid var(--primary-color);
}

[data-theme="dark"] .exercise-mission {
    background: #2a2a2a;
}

.exercise-mission strong {
    color: var(--primary-color);
}

.exercise-steps {
    margin-bottom: 20px;
}

.exercise-steps h4 {
    color: var(--text-color);
    font-size: 1rem;
    margin-bottom: 12px;
}

.exercise-steps ol {
    padding-left: 20px;
}

.exercise-steps li {
    padding: 8px 0;
    color: var(--text-color);
}

.exercise-template {
    background: white;
    border-radius: 10px;
    padding: 20px;
    position: relative;
}

[data-theme="dark"] .exercise-template {
    background: #1e1e1e;
}

.exercise-template h4 {
    color: var(--text-color);
    margin-bottom: 12px;
}

.exercise-template pre {
    background: #f5f5f5;
    padding: 15px;
    border-radius: 8px;
    overflow-x: auto;
    font-size: 13px;
    line-height: 1.6;
}

[data-theme="dark"] .exercise-template pre {
    background: #2d2d2d;
}

.exercise-template .btn-copy {
    position: absolute;
    top: 20px;
    right: 20px;
    padding: 6px 12px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 12px;
    cursor: pointer;
    transition: var(--transition);
}

.exercise-template .btn-copy:hover {
    background: var(--primary-dark);
}

.exercise-checkpoints {
    margin-top: 20px;
    padding: 15px;
    background: rgba(74, 108, 111, 0.1);
    border-radius: 10px;
}

.exercise-checkpoints h4 {
    color: var(--primary-color);
    font-size: 0.95rem;
    margin-bottom: 10px;
}

.exercise-checkpoints ul {
    list-style: none;
    padding: 0;
}

.exercise-checkpoints li {
    padding: 6px 0;
    padding-left: 25px;
    position: relative;
    color: var(--text-color);
}

.exercise-checkpoints li::before {
    content: '☐';
    position: absolute;
    left: 0;
    color: var(--primary-color);
}