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

:root {
    --primary: #6366f1;
    --primary-light: #818cf8;
    --bg: #f8fafc;
    --card-bg: #ffffff;
    --text: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --code-bg: #1e293b;
    --code-text: #e2e8f0;
    --success: #22c55e;
    --quote-border: #6366f1;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
}

body > .container {
    padding: 2rem 1.5rem;
}

/* Header */
header {
    text-align: center;
    margin-bottom: 2rem;
}

header h1 {
    font-size: 2.5rem;
    color: var(--primary);
    margin-bottom: 0.5rem;
}

.subtitle {
    color: var(--text-muted);
    font-size: 1.1rem;
}

/* Table of Contents */
.toc {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 1.5rem;
    margin-bottom: 2rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.toc h2 {
    font-size: 1rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 1rem;
}

.toc ul {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    list-style: none;
}

.toc a {
    display: inline-block;
    padding: 0.5rem 1rem;
    background: var(--bg);
    color: var(--primary);
    text-decoration: none;
    border-radius: 20px;
    font-size: 0.9rem;
    transition: all 0.2s ease;
}

.toc a:hover {
    background: var(--primary);
    color: white;
}

/* Sections */
.section {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.section h2 {
    font-size: 1.4rem;
    margin-bottom: 0.5rem;
    color: var(--text);
}

.section > p {
    color: var(--text-muted);
    margin-bottom: 1rem;
}

.section code {
    background: var(--bg);
    padding: 0.2em 0.4em;
    border-radius: 4px;
    font-family: 'SF Mono', Monaco, Consolas, monospace;
    font-size: 0.9em;
    color: var(--primary);
}

/* Example Grid */
.example-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

@media (max-width: 700px) {
    .example-grid {
        grid-template-columns: 1fr;
    }
}

/* Code Block (Left Side) */
.code-block {
    background: var(--code-bg);
    border-radius: 8px;
    overflow: hidden;
}

.code-header,
.result-header {
    padding: 0.5rem 1rem;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.code-header {
    background: #0f172a;
    color: #94a3b8;
}

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

.code-block pre {
    padding: 1rem;
    overflow-x: auto;
}

.code-block code {
    color: var(--code-text);
    font-family: 'SF Mono', Monaco, Consolas, monospace;
    font-size: 0.85rem;
    line-height: 1.5;
    background: none;
    padding: 0;
}

/* Result Block (Right Side) */
.result-block {
    background: var(--bg);
    border-radius: 8px;
    overflow: hidden;
    border: 1px solid var(--border);
}

.result-content {
    padding: 1rem;
    min-height: 120px;
}

.result-content h1 { font-size: 1.5rem; margin-bottom: 0.5rem; }
.result-content h2 { font-size: 1.3rem; margin-bottom: 0.5rem; }
.result-content h3 { font-size: 1.1rem; margin-bottom: 0.5rem; }
.result-content h4 { font-size: 1rem; margin-bottom: 0.5rem; }
.result-content p { margin-bottom: 0.5rem; }
.result-content ul, .result-content ol { padding-left: 1.5rem; margin-bottom: 0.5rem; }
.result-content li { margin-bottom: 0.25rem; }
.result-content blockquote {
    border-left: 4px solid var(--quote-border);
    padding-left: 1rem;
    color: var(--text-muted);
    margin: 0.5rem 0;
}
.result-content del { color: var(--text-muted); }

.result-content a {
    color: var(--primary);
    text-decoration: underline;
}

.result-content img {
    max-width: 150px;
    border-radius: 4px;
}

.result-content table {
    width: 100%;
    border-collapse: collapse;
}

.result-content th,
.result-content td {
    padding: 0.5rem;
    border: 1px solid var(--border);
    text-align: left;
}

.result-content th {
    background: var(--primary);
    color: white;
    font-weight: 600;
}

.result-content tr:nth-child(even) {
    background: rgba(99, 102, 241, 0.05);
}

.result-content hr {
    border: none;
    height: 2px;
    background: var(--border);
    margin: 0.75rem 0;
}

/* Task Lists */
.task-list {
    list-style: none;
    padding-left: 0 !important;
}

.task-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.task-item input[type="checkbox"] {
    width: 16px;
    height: 16px;
    accent-color: var(--primary);
}

/* Code Sample */
.code-sample {
    background: var(--code-bg);
    border-radius: 6px;
    overflow: hidden;
}

.code-sample pre {
    padding: 0.75rem;
    margin: 0;
}

.code-sample code {
    color: var(--code-text);
    font-size: 0.85rem;
    background: none;
}

/* Intro Section */
.intro-section {
    background: none;
    box-shadow: none;
    padding: 1rem 1.5rem;
    margin-bottom: 1rem;
}

.intro-section h2 {
    margin-bottom: 0.75rem;
}

.intro-section > p {
    margin-bottom: 1rem;
}

.intro-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    max-width: 700px;
    margin: 0 auto;
}

@media (max-width: 700px) {
    .intro-grid {
        grid-template-columns: 1fr;
    }
}

.intro-item {
    background: var(--bg);
    padding: 1rem;
    border-radius: 8px;
    border: 1px solid var(--border);
}

.intro-item strong {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--primary);
}

.intro-item p {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin: 0;
}

.intro-item code {
    background: var(--card-bg);
    padding: 0.1em 0.3em;
    border-radius: 3px;
    font-size: 0.85em;
    color: var(--primary);
}

kbd {
    display: inline-block;
    padding: 0.15em 0.4em;
    font-size: 0.85em;
    font-family: inherit;
    color: var(--text);
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 4px;
    box-shadow: 0 2px 0 var(--border);
}

/* Footer */
footer {
    text-align: center;
    margin-top: 2rem;
    padding: 1.5rem;
    background: var(--card-bg);
    border-radius: 12px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

footer p {
    color: var(--text-muted);
}

footer strong {
    color: var(--text);
}

.footer-note {
    margin-top: 0.5rem;
    font-size: 0.85rem;
}

/* Viewer Link */
.viewer-link {
    text-align: center;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    border-radius: 12px;
    color: white;
}

.viewer-link p {
    margin-top: 0.5rem;
    opacity: 0.9;
    font-size: 0.9rem;
}

.btn-viewer {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background: white;
    color: var(--primary);
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.2s ease;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.btn-viewer:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);
}