* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --bg-primary: #fafafa;
    --bg-secondary: #ffffff;
    --text-primary: #1a1a1a;
    --text-secondary: #4a4a4a;
    --text-muted: #6a6a6a;
    --border-color: #e5e5e5;
    --border-light: #f0f0f0;
    --accent-color: #2d6a4f;
    --hover-bg: #f0f0f0;
}

[data-theme="dark"] {
    --bg-primary: #1a1a1a;
    --bg-secondary: #242424;
    --text-primary: #f0f0f0;
    --text-secondary: #b0b0b0;
    --text-muted: #808080;
    --border-color: #404040;
    --border-light: #333333;
    --hover-bg: #2a2a2a;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    line-height: 1.6;
    overflow-x: hidden;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* ======= */

header {
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar {
    max-width: 1100px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    text-decoration: none;
}

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

.nav-links {
    display: flex;
    gap: 2rem;
}

.theme-toggle {
    background: none;
    border: 1px solid #e5e5e5;
    border-radius: 6px;
    padding: 0.5rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color 0.2s ease, border-color 0.2s ease;
}

.theme-toggle:hover {
    background-color: #f0f0f0;
    border-color: #d0d0d0;
}

.theme-toggle svg {
    width: 20px;
    height: 20px;
    color: #4a4a4a;
}

.sun-icon {
    display: none;
}

.moon-icon {
    display: block;
}

[data-theme="dark"] .sun-icon {
    display: block;
}

[data-theme="dark"] .moon-icon {
    display: none;
}

[data-theme="dark"] .theme-toggle {
    border-color: #404040;
    background-color: #2a2a2a;
}

[data-theme="dark"] .theme-toggle:hover {
    background-color: #333333;
}

[data-theme="dark"] .theme-toggle svg {
    color: #b0b0b0;
}

.nav-link {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.2s ease;
}

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

/* ======= */

main {
    max-width: 900px;
    margin: 0 auto;
    padding: 2rem;
}

/* ======= */

.blog-post {
    padding: 2rem 0;
}

.blog-post-header {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-primary);
    text-decoration: none;
    display: block;
    margin-bottom: 0.5rem;
    letter-spacing: -0.02em;
}

.blog-post-header:hover {
    color: var(--accent-color);
}

.blog-post-date {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 2rem;
}

.blog-post-content {
    color: var(--text-secondary);
    line-height: 1.8;
}

.blog-post-content p {
    margin-bottom: 1.5rem;
}

.blog-post-content a {
    color: var(--accent-color);
    text-decoration: none;
}

.blog-post-content a:hover {
    text-decoration: underline;
}

.blog-post-content img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    margin: 1.5rem auto;
    display: block;
}

.blog-post-content strong {
    color: var(--text-primary);
    font-weight: 600;
}

.blog-post-content h1,
.blog-post-content h2,
.blog-post-content h3,
.blog-post-content h4 {
    color: var(--text-primary);
    margin-top: 2rem;
    margin-bottom: 1rem;
    font-weight: 600;
}

.blog-post-content ul,
.blog-post-content ol {
    margin-bottom: 1.5rem;
    padding-left: 2rem;
}

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

.blog-post-content blockquote {
    border-left: 3px solid var(--accent-color);
    padding-left: 1rem;
    margin: 1.5rem 0;
    color: var(--text-secondary);
    font-style: italic;
}

.blog-post-content code {
    background-color: var(--hover-bg);
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    font-family: 'SF Mono', 'Monaco', 'Inconsolata', monospace;
    font-size: 0.9em;
    color: var(--text-primary);
}

.blog-post-content pre {
    background-color: var(--hover-bg);
    padding: 1rem;
    border-radius: 8px;
    overflow-x: auto;
    margin: 1.5rem 0;
}

.blog-post-content pre code {
    background: none;
    padding: 0;
}

/* ======= */

.back-link {
    display: inline-block;
    margin-bottom: 2rem;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
}

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

/* ======= */

footer {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: 2rem;
    text-align: center;
    margin-top: 4rem;
}

footer p {
    font-size: 0.85rem;
    color: var(--text-muted);
}

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

footer .footer-link:hover {
    text-decoration: underline;
}

/* ======= */

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

    .nav-links {
        gap: 1rem;
        flex-wrap: wrap;
        justify-content: center;
    }

    main {
        padding: 1rem;
    }

    .blog-post-header {
        font-size: 1.5rem;
    }
}