/* Professional academic / research site — dark theme */

:root {
    --color-bg: #0f1116;
    --color-surface: #161b22;
    --color-text: #e6edf3;
    --color-text-muted: #8b949e;
    --color-accent: #7eb8ff;
    --color-accent-hover: #a5d0ff;
    --color-border: #30363d;
    --font-sans: "DM Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    --font-serif: "Source Serif 4", Georgia, serif;
    --max-width: 720px;
    --space-unit: 1rem;
    --radius: 6px;
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

* {
    margin: 0;
    padding: 0;
}

html {
    font-size: 18px;
    -webkit-font-smoothing: antialiased;
}

body {
    font-family: var(--font-sans);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--color-text);
    background: var(--color-bg);
}

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

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

a:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-unit);
}

/* Header */
.site-header {
    padding: 0 0 1.5rem;
    border-bottom: 1px solid var(--color-border);
    background: var(--color-surface);
}

.header-inner {
    display: flex;
    flex-wrap: wrap;
    align-items: flex-start;
    justify-content: space-between;
    gap: 1rem;
}

.header-name {
    min-width: 0;
    padding-top: 2rem;
}

.site-name {
    font-family: var(--font-serif);
    font-size: 1.75rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.2;
}

.site-name a {
    color: var(--color-text);
}

.site-name a:hover {
    text-decoration: none;
    color: var(--color-accent);
}

.name-zh {
    font-weight: 400;
    color: var(--color-text-muted);
    margin-left: 0.25em;
}

.site-title {
    font-size: 0.95rem;
    color: var(--color-text-muted);
    margin-top: 0.25rem;
    font-weight: 500;
}

.header-social {
    margin-top: 0;
    padding-top: 0;
    flex-shrink: 0;
}

/* Main */
.site-main {
    padding: 2rem 0 3rem;
}

/* Intro block */
.intro {
    margin-bottom: 2.5rem;
}

.intro-grid {
    display: grid;
    grid-template-columns: 200px 1fr;
    gap: 2rem;
    align-items: start;
}

@media (max-width: 560px) {
    .intro-grid {
        grid-template-columns: 1fr;
        gap: 1.25rem;
    }
}

.intro-photo img {
    width: 200px;
    height: 200px;
    object-fit: cover;
    border-radius: var(--radius);
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.4);
}

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

.intro-content .lead {
    font-size: 1.05rem;
    color: var(--color-text);
}

.social-links {
    display: flex;
    gap: 1rem;
    margin-top: 1.25rem;
}

.social-links a.social-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-text-muted);
    transition: color 0.2s ease;
}

.social-links a.social-icon:hover {
    color: var(--color-accent);
    text-decoration: none;
}

.social-links a.social-icon svg {
    width: 64px;
    height: 64px;
    display: block;
}

/* Section blocks */
.block {
    margin-bottom: 2.5rem;
}

.block h2 {
    font-family: var(--font-serif);
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 1rem;
    padding-bottom: 0.35rem;
    border-bottom: 1px solid var(--color-border);
}

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

.list-plain li {
    margin-bottom: 0.5rem;
    padding-left: 0;
}

.list-plain li::before {
    content: none;
}

/* Footer */
.site-footer {
    padding: 1.5rem 0;
    border-top: 1px solid var(--color-border);
    background: var(--color-surface);
}

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