/* CSS Variables - Light mode defaults */
:root {
    --bg: #fafafa;
    --text: #1a1a1a;
    --text-muted: #666;
    --text-faint: #999;
    --border: #ddd;
    --border-strong: #ccc;
    --link: #0066cc;

    /* Surfaces */
    --surface: #fff;
    --surface-alt: #f5f5f5;

    /* Semantic colors */
    --accent: #0066cc;
    --accent-bg: #e6f7ff;

    --problem: #c62828;
    --problem-bg: #ffebee;

    --solution: #2e7d32;
    --solution-bg: #e8f5e9;

    --highlight: #0066cc;
    --highlight-bg: #e3f2fd;

    --os: #7b1fa2;
    --os-bg: #f3e5f5;

    --warning: #f57c00;
    --warning-bg: #fff3e0;

    /* Table */
    --th-bg: #f5f5f5;
}

/* Dark mode overrides */
@media (prefers-color-scheme: dark) {
    :root {
        --bg: #1a1a1a;
        --text: #e0e0e0;
        --text-muted: #aaa;
        --text-faint: #888;
        --border: #444;
        --border-strong: #555;
        --link: #6bb3ff;

        --surface: #252525;
        --surface-alt: #2a2a2a;

        --accent: #6bb3ff;
        --accent-bg: #1a2a3a;

        --problem: #ff6666;
        --problem-bg: #3a1a1a;

        --solution: #66cc66;
        --solution-bg: #1a3a1a;

        --highlight: #6bb3ff;
        --highlight-bg: #1a2a3a;

        --os: #ce93d8;
        --os-bg: #2a1a2a;

        --warning: #ffb74d;
        --warning-bg: #3a2a1a;

        --th-bg: #333;
    }
}

/* Base styles */
* { box-sizing: border-box; }

body {
    margin: 0;
    padding: 2rem;
    font-family: Georgia, serif;
    font-size: 18px;
    line-height: 1.7;
    color: var(--text);
    background: var(--bg);
    max-width: 900px;
    margin: 0 auto;
}

/* Header */
header {
    text-align: center;
    margin-bottom: 3rem;
    padding-bottom: 2rem;
    border-bottom: 2px solid var(--border);
}

h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    line-height: 1.2;
}

.subtitle {
    font-size: 1.3rem;
    color: var(--text-muted);
    font-style: italic;
    margin-bottom: 1.5rem;
}

.intro {
    font-size: 1.1rem;
    max-width: 700px;
    margin: 0 auto;
    text-align: left;
}

.intro p {
    margin-bottom: 0.75rem;
}

/* Section headings */
h2 {
    font-size: 1.8rem;
    margin-top: 3rem;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--border);
}

.section-subtitle {
    display: block;
    font-size: 1rem;
    font-weight: normal;
    color: var(--text-muted);
    margin-top: 0.25rem;
}

/* Accordion items */
details {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 6px;
    margin-bottom: 1rem;
}

details[open] {
    padding-bottom: 1.5rem;
}

summary {
    padding: 1rem 1.5rem;
    cursor: pointer;
    font-weight: 600;
    display: flex;
    justify-content: space-between;
    align-items: center;
    list-style: none;
}

summary::-webkit-details-marker {
    display: none;
}

summary::after {
    content: '+';
    font-size: 1.5rem;
    color: var(--text-muted);
    flex-shrink: 0;
}

details[open] summary::after {
    content: '−';
}

summary:hover {
    background: var(--surface-alt);
}

.summary-title {
    font-size: 1.2rem;
    color: var(--accent);
}

.os-section .summary-title {
    color: var(--os);
}

.summary-subtitle {
    font-size: 0.9rem;
    color: var(--text-muted);
    font-weight: normal;
    margin-left: 1rem;
}

/* Content inside accordions */
.content {
    padding: 0 1.5rem;
}

.content h3 {
    font-size: 1.1rem;
    margin-top: 1.5rem;
    margin-bottom: 0.75rem;
}

.content h4 {
    font-size: 0.95rem;
    margin-top: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-weight: 600;
}

.content ul, .content ol {
    margin-left: 1.5rem;
    margin-bottom: 1rem;
}

.content li {
    margin-bottom: 0.5rem;
}

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

/* Tables */
table {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
    font-size: 0.95rem;
}

th, td {
    padding: 0.75rem;
    text-align: left;
    border: 1px solid var(--border);
}

th {
    background: var(--th-bg);
    font-weight: 600;
}

/* Content boxes */
.problem-box {
    background: var(--problem-bg);
    border-left: 4px solid var(--problem);
    padding: 1rem 1.5rem;
    margin: 1rem 0;
    border-radius: 0 4px 4px 0;
}

.solution-box {
    background: var(--solution-bg);
    border-left: 4px solid var(--solution);
    padding: 1rem 1.5rem;
    margin: 1rem 0;
    border-radius: 0 4px 4px 0;
}

.highlight-box {
    background: var(--highlight-bg);
    border-left: 4px solid var(--highlight);
    padding: 1rem 1.5rem;
    margin: 1rem 0;
    border-radius: 0 4px 4px 0;
}

.os-box {
    background: var(--os-bg);
    border-left: 4px solid var(--os);
    padding: 1rem 1.5rem;
    margin: 1rem 0;
    border-radius: 0 4px 4px 0;
}

.os-intro {
    margin-bottom: 1.5rem;
}

.os-intro p {
    margin: 0;
}

.os-intro p + p {
    margin-top: 0.5rem;
}

/* Initiative cards */
.initiative-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 2rem;
}

.initiative-card h3 {
    margin-top: 0;
    margin-bottom: 1rem;
    font-size: 1.4rem;
}

.initiative-card h3 a {
    color: var(--accent);
    text-decoration: none;
}

.initiative-card h3 a:hover {
    text-decoration: underline;
}

.initiative-card.os h3 a {
    color: var(--os);
}

/* Proposal line */
.initiative-card .proposal {
    margin-top: 1rem;
    padding: 0.75rem 1rem;
    background: var(--solution-bg);
    border-left: 3px solid var(--solution);
    border-radius: 0 4px 4px 0;
}

/* Note */
.initiative-card .note {
    font-size: 0.9rem;
    font-style: italic;
    color: var(--text-muted);
    margin-top: 0.75rem;
    padding: 0.75rem 1rem;
    background: var(--surface-alt);
    border-radius: 4px;
}

/* Section intro */
.section-intro {
    margin-bottom: 1.5rem;
    color: var(--text-muted);
}

/* Steal section */
.steal-section {
    background: var(--warning-bg);
    padding: 2rem;
    border-radius: 8px;
    margin-top: 2.5rem;
    border: 2px dashed var(--warning);
}

.steal-section h3 {
    margin-top: 0;
    font-size: 1.3rem;
}

.steal-section ul {
    margin-left: 1.5rem;
}

.steal-section li {
    margin-bottom: 0.5rem;
}

/* Footer */
footer {
    margin-top: 4rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
}

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

footer a:hover {
    text-decoration: underline;
}

footer p {
    margin: 0.25rem 0;
}

/* Links */
a {
    color: var(--link);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* Mobile responsiveness */
@media (max-width: 768px) {
    body {
        padding: 1rem;
        font-size: 16px;
    }

    h1 {
        font-size: 1.8rem;
    }

    h2 {
        font-size: 1.4rem;
        margin-top: 2rem;
    }

    .subtitle {
        font-size: 1.1rem;
    }

    .summary-subtitle {
        display: none;
    }

    summary {
        padding: 0.75rem 1rem;
    }

    .content {
        padding: 0 1rem;
    }

    .problem-box, .solution-box, .highlight-box, .os-box {
        padding: 0.75rem 1rem;
    }

    .steal-section {
        padding: 1.5rem;
    }

    table {
        font-size: 0.85rem;
    }

    th, td {
        padding: 0.5rem;
    }
}