/* === Design Tokens === */
:root {
    --bg-page: #0f0f0f;
    --bg-card: #161616;
    --bg-surface: #1e1e1e;
    --text-primary: #e8e8e8;
    --text-secondary: #999;
    --text-tertiary: #555;
    --accent: #1D9E75;
    --border: #222;
    --border-width: 0.5px;
}

:root.light {
    --bg-page: #f8f8f6;
    --bg-card: #ffffff;
    --bg-surface: #f0f0ec;
    --text-primary: #111;
    --text-secondary: #555;
    --text-tertiary: #aaa;
    --accent: #0F6E56;
    --border: #e5e5e0;
}

/* === Global === */
* {
    box-sizing: border-box;
}

body {
    background-color: var(--bg-page);
    color: var(--text-primary);
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    margin: 0;
    transition: color 0.2s, background-color 0.2s, border-color 0.2s;
}

a {
    color: inherit;
    text-decoration: none;
}

/* === Layout === */
.container {
    max-width: 640px;
    margin: 0 auto;
    padding: 56px 24px 0;
}

/* === Nav === */
nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 32px;
    border-bottom: var(--border-width) solid var(--border);
    transition: background-color 0.2s, color 0.2s, border-color 0.2s;
}

.nav-logo {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 24px;
}

.nav-link {
    font-size: 13px;
    color: var(--text-secondary);
    transition: color 0.2s;
}

.nav-link:hover {
    color: var(--text-primary);
}

/* === Theme Toggle === */
.theme-toggle {
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: 99px;
    padding: 4px;
    display: flex;
    gap: 2px;
    cursor: pointer;
    align-items: center;
}

.theme-toggle-icon {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-tertiary);
    transition: all 0.2s;
}

.theme-toggle-icon.active {
    background: var(--accent);
    color: white;
}

/* === Hero === */
.hero {
    margin-bottom: 48px;
}

.eyebrow {
    font-size: 11px;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--text-tertiary);
    margin-bottom: 16px;
}

.hero h1 {
    font-size: 30px;
    font-weight: 700;
    line-height: 1.3;
    margin: 0 0 20px;
}

.accent {
    color: var(--accent);
}

.hero .lead {
    font-size: 15px;
    line-height: 1.8;
    color: var(--text-secondary);
    max-width: 520px;
    margin: 0;
}

/* === Section Labels === */
.section-label {
    font-size: 10px;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--text-tertiary);
    margin-bottom: 16px;
}

/* === Project Grid === */
.project-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
    margin-bottom: 48px;
}

.project-card {
    border: var(--border-width) solid var(--border);
    border-radius: 12px;
    padding: 20px;
    background: var(--bg-card);
    transition: border-color 0.2s, background-color 0.2s, color 0.2s;
}

.project-card:hover {
    border-color: var(--accent);
}

.project-tag {
    font-size: 10px;
    font-family: monospace;
    color: var(--accent);
    margin: 0 0 12px;
    text-transform: lowercase;
}

.project-title {
    font-size: 15px;
    font-weight: 500;
    margin: 0 0 8px;
}

.project-link {
    color: var(--text-primary);
    text-decoration: none;
}

.project-link:hover {
    color: var(--accent);
}

.project-desc {
    font-size: 13px;
    color: var(--text-secondary);
    line-height: 1.6;
    margin: 0 0 16px;
}

.project-desc a {
    color: var(--accent);
    text-decoration: none;
}

.project-desc a:hover {
    text-decoration: underline;
}

.project-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.project-cta {
    font-size: 12px;
    color: var(--accent);
    text-decoration: none;
}

.project-cta:hover {
    text-decoration: underline;
}

.project-about {
    font-size: 12px;
    color: var(--text-tertiary);
    text-decoration: none;
}

.project-about:hover {
    color: var(--accent);
    text-decoration: underline;
}

.external-icon {
    margin-left: 2px;
    vertical-align: middle;
}

/* === Writing List === */
.writing-list {
    margin-bottom: 48px;
}

.writing-row {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    padding: 12px 0;
    border-bottom: var(--border-width) solid var(--border);
    transition: border-color 0.2s;
}

.writing-title {
    font-size: 14px;
    color: var(--text-primary);
}

.writing-date {
    font-size: 11px;
    color: var(--text-tertiary);
    white-space: nowrap;
    margin-left: 16px;
}

.writing-coming-soon {
    font-size: 13px;
    color: var(--text-tertiary);
    margin: 0;
    padding: 12px 0;
}

/* === Footer === */
footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 24px 32px;
    border-top: var(--border-width) solid var(--border);
    margin-top: 48px;
    transition: background-color 0.2s, color 0.2s, border-color 0.2s;
}

.footer-copyright {
    font-size: 12px;
    color: var(--text-tertiary);
}

.footer-links {
    display: flex;
    gap: 20px;
}

.footer-link {
    font-size: 12px;
    color: var(--text-secondary);
    transition: color 0.2s;
}

.footer-link:hover {
    color: var(--text-primary);
}

/* === 404 Page === */
.error-page {
    text-align: center;
    padding: 80px 24px;
}

.error-gif-container {
    display: inline-block;
    background: white;
    border-radius: 12px;
    padding: 8px;
    margin-bottom: 32px;
}

.error-page h1 {
    font-size: 48px;
    font-weight: 700;
    margin: 0 0 8px;
    color: var(--text-primary);
}

.error-page p {
    font-size: 15px;
    color: var(--text-secondary);
    margin: 0 0 24px;
}

.error-home-link {
    font-size: 14px;
    color: var(--accent);
}

/* === Focus States (Accessibility) === */
a:focus-visible,
button:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
    border-radius: 4px;
}

/* === Responsive === */
@media (max-width: 640px) {
    .project-grid {
        grid-template-columns: 1fr;
    }

    nav {
        padding: 12px 16px;
    }

    .nav-links {
        flex-wrap: wrap;
        gap: 12px;
    }

    .container {
        padding-left: 24px;
        padding-right: 24px;
    }

    footer {
        padding: 24px 16px;
        flex-direction: column;
        gap: 12px;
        text-align: center;
    }
}