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

:root {
    --primary-color: #6200EE;
    --primary-dark: #3700B3;
    --secondary-color: #03DAC6;
    --background-color: #F5F5F5;
    --surface-color: #FFFFFF;
    --text-primary: #212121;
    --text-secondary: #757575;
    --border-color: #E0E0E0;
    --shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 4px 8px rgba(0, 0, 0, 0.15);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--background-color);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header and Navigation */
.main-header {
    background-color: var(--surface-color);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand h1 {
    font-size: 1.5rem;
    color: var(--primary-color);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    transition: background-color 0.3s ease;
}

.nav-link:hover,
.nav-link.active {
    background-color: var(--primary-color);
    color: white;
}

/* Main Content */
.main-content {
    flex: 1;
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
    padding: 2rem;
}

.page {
    display: none;
}

.page.active {
    display: block;
}

/* Home Page */
.hero-section {
    text-align: center;
    padding: 3rem 0;
}

.hero-section h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.hero-section > p {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 3rem;
}

.feature-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.feature-card {
    background-color: var(--surface-color);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

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

.feature-card h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

/* Tutorials Page */
.tutorials-container h2 {
    font-size: 2rem;
    margin-bottom: 2rem;
    color: var(--primary-color);
}

.category-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid var(--border-color);
}

.category-btn {
    padding: 0.75rem 1.5rem;
    background-color: var(--surface-color);
    border: 2px solid var(--border-color);
    border-radius: 25px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 500;
    color: var(--text-primary);
    transition: all 0.3s ease;
}

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

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

.tutorials-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}

.tutorial-card {
    background-color: var(--surface-color);
    border-radius: 8px;
    padding: 1.5rem;
    box-shadow: var(--shadow);
    cursor: pointer;
    transition: all 0.3s ease;
    border-left: 4px solid var(--primary-color);
}

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

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

.tutorial-card .category-badge {
    display: inline-block;
    background-color: var(--secondary-color);
    color: var(--text-primary);
    padding: 0.25rem 0.75rem;
    border-radius: 12px;
    font-size: 0.85rem;
    margin-bottom: 0.75rem;
}

.tutorial-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* Tutorial Detail Page */
.tutorial-detail-container {
    max-width: 900px;
    margin: 0 auto;
}

.back-btn {
    padding: 0.75rem 1.5rem;
    background-color: var(--surface-color);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    margin-bottom: 2rem;
    transition: all 0.3s ease;
}

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

.tutorial-detail {
    background-color: var(--surface-color);
    border-radius: 8px;
    padding: 2rem;
    box-shadow: var(--shadow);
}

.tutorial-detail h2 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 2rem;
}

.tutorial-detail .category-badge {
    display: inline-block;
    background-color: var(--secondary-color);
    color: var(--text-primary);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
}

.tutorial-section {
    margin-bottom: 2.5rem;
}

.tutorial-section h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.5rem;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 0.5rem;
}

.tutorial-section p {
    margin-bottom: 1rem;
    line-height: 1.8;
}

/* Syntax Box */
.syntax-box {
    background-color: #1E1E1E;
    color: #D4D4D4;
    padding: 1.5rem;
    border-radius: 8px;
    margin: 1rem 0;
    overflow-x: auto;
    font-family: 'Courier New', monospace;
    font-size: 0.95rem;
    line-height: 1.6;
}

.syntax-box code {
    color: #CE9178;
}

.syntax-box .keyword {
    color: #569CD6;
}

.syntax-box .function {
    color: #DCDCAA;
}

.syntax-box .string {
    color: #CE9178;
}

/* Use Case Box */
.use-case-box {
    background-color: #E3F2FD;
    border-left: 4px solid var(--primary-color);
    padding: 1.5rem;
    border-radius: 4px;
    margin: 1rem 0;
}

.use-case-box h4 {
    color: var(--primary-color);
    margin-bottom: 0.75rem;
}

/* Image Placeholder */
.image-placeholder {
    background-color: var(--border-color);
    border: 2px dashed var(--text-secondary);
    border-radius: 8px;
    padding: 3rem;
    text-align: center;
    color: var(--text-secondary);
    margin: 1.5rem 0;
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.image-placeholder::before {
    content: "📷 Image Placeholder";
    font-size: 1.2rem;
}

/* Code Editor Section */
.code-editor-section {
    margin-top: 2rem;
}

.code-editor-section h3 {
    margin-bottom: 1rem;
}

.code-editor {
    width: 100%;
    min-height: 300px;
    background-color: #1E1E1E;
    color: #D4D4D4;
    font-family: 'Courier New', monospace;
    font-size: 0.95rem;
    padding: 1.5rem;
    border-radius: 8px;
    border: none;
    resize: vertical;
    line-height: 1.6;
}

.code-editor:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

.run-btn {
    margin-top: 1rem;
    padding: 0.75rem 2rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

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

.run-btn:active {
    transform: scale(0.98);
}

.output-box {
    margin-top: 1rem;
    padding: 1.5rem;
    background-color: var(--surface-color);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    min-height: 100px;
    display: none;
}

.output-box.active {
    display: block;
}

.output-box h4 {
    color: var(--primary-color);
    margin-bottom: 0.75rem;
}

/* Footer */
.main-footer {
    background-color: var(--surface-color);
    text-align: center;
    padding: 2rem;
    margin-top: 3rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
}

/* Responsive Design */
@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
        gap: 1rem;
    }

    .nav-menu {
        gap: 1rem;
    }

    .hero-section h2 {
        font-size: 2rem;
    }

    .feature-cards {
        grid-template-columns: 1fr;
    }

    .tutorials-list {
        grid-template-columns: 1fr;
    }

    .main-content {
        padding: 1rem;
    }

    .tutorial-detail {
        padding: 1.5rem;
    }
}

/* Accessibility */
*:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

button:focus,
a:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* Screen Reader Only */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* Loading Spinner */
.loading-spinner {
    border: 4px solid #f3f3f3;
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 0 auto 15px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Code Editor Improvements */
.code-editor-section h3 {
    color: var(--primary-color);
}

.code-editor {
    font-family: 'Courier New', 'Monaco', 'Menlo', monospace;
    tab-size: 4;
}

.output-box pre {
    font-family: 'Courier New', 'Monaco', 'Menlo', monospace;
    font-size: 0.9rem;
    line-height: 1.5;
}