/* System Notes - Vanilla CSS */

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

:root {
    --bg: #ffffff;
    --text: #1a1a1a;
    --text-muted: #5a5a5a;
    --border: #e0e0e0;
    --accent: #003d7a;
    --accent-hover: #002952;
    --accent-light: #e8f0f7;
    --secondary: #2d7a3e;
    --secondary-hover: #1f5229;
    --code-bg: #f8f9fa;
    --max-width: 1200px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    font-size: 18px;
    line-height: 1.7;
    color: var(--text);
    background: var(--bg);
}

/* Header & Navigation */
header {
    border-bottom: 2px solid var(--accent);
    margin-bottom: 1.5rem;
    background: linear-gradient(to bottom, var(--bg) 0%, var(--accent-light) 100%);
}

nav {
    padding: 0.75rem 0;
}

.nav-container {
    margin: 0;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.site-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--accent);
    text-decoration: none;
    letter-spacing: -0.02em;
}

.site-title:hover {
    color: var(--accent-hover);
}

.site-subtitle {
    font-size: 0.7rem;
    color: var(--text-muted);
    margin-top: 0.05rem;
}

.site-subtitle a {
    color: var(--text-muted);
    text-decoration: none;
}

.site-subtitle a:hover {
    color: var(--accent);
}

.nav-links {
    display: flex;
    gap: 1.5rem;
    list-style: none;
}

.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.95rem;
}

.nav-links a:hover {
    color: var(--accent);
}

/* Main Content */
main {
    margin: 0;
    padding: 0 2rem 2rem;
}

article {
    margin-bottom: 1.5rem;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    margin-top: 1.25rem;
    margin-bottom: 0.75rem;
}

h1 {
    font-size: 2.25rem;
    margin-top: 0;
}

h2 {
    font-size: 1.75rem;
    border-bottom: 2px solid var(--accent);
    padding-bottom: 0.5rem;
    color: var(--accent);
}

h3 {
    font-size: 1.4rem;
}

p {
    margin-bottom: 0.9rem;
}

a {
    color: var(--accent);
    text-decoration: underline;
}

a:hover {
    color: var(--accent-hover);
}

/* Lists */
ul, ol {
    margin-left: 1.5rem;
    margin-bottom: 0.9rem;
}

li {
    margin-bottom: 0.3rem;
}

/* Code */
code {
    font-family: "SF Mono", Monaco, "Cascadia Code", "Roboto Mono", Consolas, monospace;
    font-size: 0.9em;
    background: var(--code-bg);
    padding: 0.2em 0.4em;
    border-radius: 3px;
}

pre {
    background: var(--code-bg);
    padding: 0.75rem;
    border-radius: 5px;
    overflow-x: auto;
    margin-bottom: 0.9rem;
}

pre code {
    background: none;
    padding: 0;
}

/* Blockquotes */
blockquote {
    border-left: 3px solid var(--accent);
    padding-left: 1rem;
    margin: 1rem 0;
    color: var(--text-muted);
    font-style: italic;
}

/* Horizontal Rules */
hr {
    border: none;
    border-top: 1px solid var(--border);
    margin: 1.25rem 0;
}

/* Tables */
table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 0.9rem;
}

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

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

/* Notes Index */
.notes-index {
    margin-top: 1rem;
}

.theme-group {
    margin-bottom: 2rem;
}

.theme-group h2 {
    margin-bottom: 0.75rem;
}

.note-list {
    list-style: none;
    margin-left: 0;
}

.note-item {
    margin-bottom: 0.9rem;
    padding: 0.75rem;
    border-left: 3px solid var(--accent);
    border-top: 1px solid var(--border);
    border-right: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    border-radius: 3px;
    transition: all 0.2s ease;
}

.note-item:hover {
    border-left-color: var(--secondary);
    border-left-width: 4px;
    background: var(--accent-light);
    transform: translateX(2px);
}

.note-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.35rem;
}

.note-title a {
    color: var(--text);
    text-decoration: none;
}

.note-title a:hover {
    color: var(--accent);
}

.note-description {
    color: var(--text-muted);
    font-size: 0.95rem;
}

/* Footer */
footer {
    border-top: 2px solid var(--accent);
    margin-top: 2rem;
    padding: 1rem 0.25rem;
    background: var(--accent-light);
}

.footer-container {
    margin: 0;
    padding: 0 2rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* 404 Page */
.error-page {
    text-align: center;
    padding: 4rem 1rem;
}

.error-page h1 {
    font-size: 4rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.error-page h2 {
    border: none;
    margin-bottom: 1rem;
}

/* Responsive */
@media (max-width: 768px) {
    body {
        font-size: 16px;
    }

    main {
        padding: 0 2rem 1.5rem;
    }

    .nav-container {
        padding: 0 2rem;
    }

    h1 {
        font-size: 1.75rem;
    }

    h2 {
        font-size: 1.4rem;
    }

    .site-title {
        font-size: 1.5rem;
    }

    .nav-container {
        flex-direction: column;
        gap: 0.75rem;
    }

    .nav-links {
        gap: 1rem;
    }
}