/* CSS Variables for Theming */
:root {
    --primary-color: #4f46e5;
    --primary-hover: #4338ca;
    --secondary-color: #10b981;
    --danger-color: #ef4444;
    --text-main: #1f2937;
    --text-muted: #6b7280;
    --bg-main: #f9fafb;
    --bg-sidebar: #ffffff;
    --bg-card: #ffffff;
    --border-color: #e5e7eb;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --transition: all 0.3s ease;
    --font-family: 'Inter', sans-serif;
    --chat-bot-bg: #e0e7ff;
    --chat-user-bg: #4f46e5;
    --chat-user-text: white;
}

body.dark-mode {
    --text-main: #f3f4f6;
    --text-muted: #9ca3af;
    --bg-main: #111827;
    --bg-sidebar: #1f2937;
    --bg-card: #1f2937;
    --border-color: #374151;
    --chat-bot-bg: #374151;
    --chat-user-bg: #4f46e5;
}

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

body {
    font-family: var(--font-family);
    background-color: var(--bg-main);
    color: var(--text-main);
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
    overflow-x: hidden;
}

h1, h2, h3, h4 {
    color: var(--text-main);
    margin-bottom: 0.5rem;
}

a {
    color: var(--primary-color);
    text-decoration: none;
}

/* Layout */
#app-container {
    display: flex;
    height: 100vh;
    overflow: hidden;
}

/* Sidebar */
#sidebar {
    width: 280px;
    background-color: var(--bg-sidebar);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    transition: transform 0.3s ease;
    z-index: 100;
}

.sidebar-header {
    padding: 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
}

.sidebar-header h2 {
    font-size: 1.2rem;
    margin: 0;
}

.icon-btn {
    background: none;
    border: none;
    font-size: 1.2rem;
    cursor: pointer;
    color: var(--text-main);
}

.sidebar-progress {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border-color);
    font-size: 0.9rem;
}

.progress-bar-container {
    background-color: var(--border-color);
    border-radius: 9999px;
    height: 8px;
    margin: 0.5rem 0;
    overflow: hidden;
}

.progress-bar {
    background-color: var(--secondary-color);
    height: 100%;
    transition: width 0.5s ease;
}

#module-nav {
    flex: 1;
    overflow-y: auto;
    padding: 1rem 0;
}

.nav-item {
    display: block;
    padding: 0.75rem 1.5rem;
    color: var(--text-main);
    cursor: pointer;
    transition: var(--transition);
    border-left: 4px solid transparent;
}

.nav-item:hover, .nav-item.active {
    background-color: rgba(79, 70, 229, 0.1);
    border-left-color: var(--primary-color);
    color: var(--primary-color);
    font-weight: 600;
}

.nav-item .progress-pill {
    float: right;
    font-size: 0.75rem;
    background: var(--border-color);
    padding: 2px 6px;
    border-radius: 10px;
}

.sidebar-footer {
    padding: 1.5rem;
    border-top: 1px solid var(--border-color);
}

.full-width-btn {
    width: 100%;
    padding: 0.75rem;
    border: none;
    border-radius: 0.375rem;
    cursor: pointer;
    font-weight: 600;
    transition: var(--transition);
}

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

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

.secondary-btn {
    background-color: transparent;
    color: var(--text-main);
    border: 1px solid var(--border-color);
}

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

.streak-tracker {
    margin-top: 1rem;
    text-align: center;
    font-size: 0.9rem;
    font-weight: 600;
    color: #f59e0b;
}

/* Main Content */
#main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

#content-header {
    padding: 1.5rem 2rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: var(--bg-main);
}

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

.header-left h1 {
    margin: 0;
    font-size: 1.5rem;
}

#header-breadcrumbs {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.mobile-only {
    display: none;
}

#dynamic-container {
    flex: 1;
    overflow-y: auto;
    padding: 2rem;
}

/* Dashboard Cards */
.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}

.module-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    padding: 1.5rem;
    box-shadow: var(--shadow);
    transition: transform 0.2s, box-shadow 0.2s;
    cursor: pointer;
}

.module-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    border-color: var(--primary-color);
}

.module-card h3 {
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.module-card p {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.module-card .card-progress {
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* Lesson Rendering styles */
.lesson-content {
    max-width: 800px;
    margin: 0 auto;
    background: var(--bg-card);
    padding: 2.5rem;
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
}

.lesson-content h2 {
    color: var(--primary-color);
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 0.5rem;
    margin-top: 1.5rem;
    margin-bottom: 1rem;
}

.lesson-content p {
    margin-bottom: 1rem;
}

.lesson-content ul {
    margin-bottom: 1rem;
    padding-left: 2rem;
}

.lesson-content blockquote {
    border-left: 4px solid var(--primary-color);
    padding-left: 1rem;
    color: var(--text-muted);
    font-style: italic;
    margin: 1.5rem 0;
    background: rgba(79, 70, 229, 0.05);
    padding: 1rem;
    border-radius: 0 0.5rem 0.5rem 0;
}

.simulator-container {
    background-color: var(--bg-main);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    padding: 1.5rem;
    margin: 2rem 0;
}

.simulator-controls {
    display: flex;
    gap: 1rem;
    align-items: center;
    flex-wrap: wrap;
    margin-bottom: 1rem;
}

.lesson-nav-buttons {
    display: flex;
    justify-content: space-between;
    margin-top: 3rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-color);
}

.btn {
    padding: 0.5rem 1rem;
    border-radius: 0.375rem;
    border: none;
    cursor: pointer;
    font-weight: 500;
    transition: var(--transition);
}

/* Quiz Styles */
.quiz-container {
    max-width: 600px;
    margin: 0 auto;
}

.quiz-card {
    background: var(--bg-card);
    padding: 2rem;
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
    margin-bottom: 1.5rem;
}

.quiz-question {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
}

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

.quiz-option {
    background: var(--bg-main);
    border: 1px solid var(--border-color);
    padding: 1rem;
    border-radius: 0.375rem;
    cursor: pointer;
    transition: var(--transition);
}

.quiz-option:hover {
    background: rgba(79, 70, 229, 0.05);
    border-color: var(--primary-color);
}

.quiz-option.selected {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

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

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

#quiz-feedback {
    margin-top: 1rem;
    font-weight: 600;
}

/* Chatbot Styles */
#chat-widget {
    position: fixed;
    bottom: 20px;
    right: 20px;
    width: 300px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
    display: flex;
    flex-direction: column;
    transition: height 0.3s ease, transform 0.3s ease;
    z-index: 1000;
    overflow: hidden;
}

#chat-widget.collapsed {
    height: 40px;
}

#chat-widget:not(.collapsed) {
    height: 400px;
}

#chat-header {
    background: var(--primary-color);
    color: white;
    padding: 10px 15px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    font-weight: 600;
}

#chat-header button {
    background: none;
    border: none;
    color: white;
    cursor: pointer;
}

#chat-body {
    display: flex;
    flex-direction: column;
    flex: 1;
    padding: 10px;
    overflow: hidden;
}

#chat-messages {
    flex: 1;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-bottom: 10px;
    padding-right: 5px;
}

.message {
    max-width: 80%;
    padding: 8px 12px;
    border-radius: 12px;
    font-size: 0.9rem;
}

.message.bot {
    align-self: flex-start;
    background-color: var(--chat-bot-bg);
    color: var(--text-main);
    border-bottom-left-radius: 2px;
}

.message.user {
    align-self: flex-end;
    background-color: var(--chat-user-bg);
    color: var(--chat-user-text);
    border-bottom-right-radius: 2px;
}

#chat-input-area {
    display: flex;
    gap: 5px;
}

#chat-input {
    flex: 1;
    padding: 8px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background: var(--bg-main);
    color: var(--text-main);
}

#chat-send {
    padding: 8px 12px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}

/* Animations */
.fade-in {
    animation: fadeIn 0.3s ease-in;
}

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

/* Responsive */
@media (max-width: 768px) {
    #sidebar {
        position: absolute;
        height: 100%;
        transform: translateX(-100%);
    }
    
    #sidebar.open {
        transform: translateX(0);
    }
    
    .mobile-only {
        display: block;
    }
    
    .lesson-content {
        padding: 1.5rem;
    }
}

/* SVG Diagram Styling */
.svg-diagram {
    display: block;
    margin: 2rem auto;
    max-width: 100%;
    height: auto;
    background-color: var(--bg-card);
    border-radius: 0.5rem;
    padding: 1rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

/* Practice Problems Accordion */
details.practice-problem {
    background: var(--bg-main);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    padding: 1rem;
    margin: 1.5rem 0;
    transition: var(--transition);
}

details.practice-problem[open] {
    border-color: var(--primary-color);
    background: rgba(79, 70, 229, 0.05);
}

details.practice-problem summary {
    font-weight: 600;
    color: var(--primary-color);
    cursor: pointer;
    list-style: none;
}

details.practice-problem summary::-webkit-details-marker {
    display: none;
}

.practice-solution {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-main);
}