:root {
    --bg-color: #fff;
    --text-color: #333;
    --heading-color: #111;
    --secondary-text: #666;
    --meta-text: #888;
    --border-color: #eaeaea;
    --link-color: #0066cc;
    --contribution-bg: #ebedf0;
    --contribution-border: rgba(27, 31, 35, 0.06);
    --contribution-section-border: #e1e4e8;
}

[data-theme="dark"] {
    --bg-color: #0d1117;
    --text-color: #c9d1d9;
    --heading-color: #f0f6fc;
    --secondary-text: #8b949e;
    --meta-text: #6e7681;
    --border-color: #30363d;
    --link-color: #58a6ff;
    --contribution-bg: #161b22;
    --contribution-border: rgba(240, 246, 252, 0.05);
    --contribution-section-border: #30363d;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    margin: 0;
    padding: 0;
    transition: background-color 0.3s, color 0.3s;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

/* Header */
header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 40px 0;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 40px;
}

header h1 {
    margin: 0;
    font-size: 1.5rem;
    font-weight: 700;
}

header h1 a {
    text-decoration: none;
    color: var(--heading-color);
}

header nav {
    display: flex;
    align-items: center;
    gap: 20px;
}

header nav ul {
    list-style: none;
    display: flex;
    gap: 20px;
    margin: 0;
    padding: 0;
}

header nav a {
    text-decoration: none;
    color: var(--secondary-text);
    font-size: 0.9rem;
    transition: color 0.2s;
}

header nav a:hover {
    color: var(--heading-color);
}

/* Theme Toggle */
#theme-toggle {
    background: none;
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 5px 10px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.8rem;
    transition: all 0.2s;
}

#theme-toggle:hover {
    background-color: var(--border-color);
}

/* Main Content */
article {
    margin-bottom: 60px;
}

article h2 {
    font-size: 1.8rem;
    margin-bottom: 10px;
}

article h2 a {
    text-decoration: none;
    color: var(--heading-color);
}

article h2 a:hover {
    text-decoration: underline;
}

.post-meta {
    font-size: 0.85rem;
    color: var(--meta-text);
    margin-bottom: 15px;
}

.post-excerpt {
    font-size: 1rem;
    color: var(--text-color);
}

.read-more {
    display: inline-block;
    margin-top: 10px;
    color: var(--link-color);
    text-decoration: none;
    font-weight: 500;
}

.read-more:hover {
    text-decoration: underline;
}

/* Full Post View */
.back-link {
    display: inline-block;
    margin-bottom: 20px;
    color: var(--secondary-text);
    text-decoration: none;
    font-size: 0.9rem;
}

.back-link:hover {
    color: var(--heading-color);
    text-decoration: underline;
}

.full-post h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    color: var(--heading-color);
}

.post-content {
    margin-top: 30px;
    font-size: 1.1rem;
    line-height: 1.8;
}

.post-content h3 {
    margin-top: 40px;
    color: var(--heading-color);
}

.post-content p {
    margin-bottom: 20px;
}

.post-content ul {
    margin-bottom: 20px;
    padding-left: 20px;
}

/* Page Content (About, Contact) */
.page-content h1 {
    font-size: 2.5rem;
    margin-bottom: 20px;
    color: var(--heading-color);
}

.page-content h3 {
    margin-top: 30px;
    color: var(--heading-color);
}

.page-content p {
    margin-bottom: 15px;
    font-size: 1.1rem;
}

.page-content ul {
    margin-bottom: 20px;
    padding-left: 20px;
}

.page-content li {
    margin-bottom: 10px;
    font-size: 1.1rem;
}

.contact-info {
    background-color: var(--contribution-bg);
    padding: 20px;
    border-radius: 8px;
    margin: 20px 0;
    border: 1px solid var(--contribution-section-border);
}

.contact-info p {
    margin-bottom: 10px;
}

.contact-info a {
    color: var(--link-color);
    text-decoration: none;
}

.contact-info a:hover {
    text-decoration: underline;
}

/* Footer */
footer {
    text-align: center;
    padding: 40px 0;
    color: var(--meta-text);
    font-size: 0.85rem;
    border-top: 1px solid var(--border-color);
    margin-top: 60px;
}

/* Contribution Graph */
#contribution-section {
    margin-bottom: 60px;
    padding: 20px;
    border: 1px solid var(--contribution-section-border);
    border-radius: 6px;
}

.contribution-header h2 {
    font-size: 1rem;
    font-weight: 400;
    margin-bottom: 10px;
    color: var(--heading-color);
}

.contribution-graph {
    display: grid;
    grid-template-rows: repeat(7, 10px);
    grid-auto-flow: column;
    grid-auto-columns: 10px;
    gap: 2px;
    overflow-x: auto;
    padding-bottom: 10px;
}

.day {
    width: 10px;
    height: 10px;
    border-radius: 2px;
    background-color: var(--contribution-bg);
    outline: 1px solid var(--contribution-border);
    outline-offset: -1px;
}

.day[data-level="1"] { background-color: #0e4429; }
.day[data-level="2"] { background-color: #006d32; }
.day[data-level="3"] { background-color: #26a641; }
.day[data-level="4"] { background-color: #39d353; }

/* Light mode overrides for graph if needed, but the green levels usually look okay on both */
:root:not([data-theme="dark"]) .day[data-level="1"] { background-color: #9be9a8; }
:root:not([data-theme="dark"]) .day[data-level="2"] { background-color: #40c463; }
:root:not([data-theme="dark"]) .day[data-level="3"] { background-color: #30a14e; }
:root:not([data-theme="dark"]) .day[data-level="4"] { background-color: #216e39; }

.contribution-footer {
    display: flex;
    justify-content: flex-end;
    align-items: center;
    gap: 5px;
    font-size: 12px;
    color: var(--secondary-text);
    margin-top: 10px;
}

.legend {
    display: flex;
    gap: 2px;
    list-style: none;
    margin: 0;
    padding: 0;
}

.legend li {
    width: 10px;
    height: 10px;
    border-radius: 2px;
}