/* ── Base ────────────────────────────────────────── */

:root {
    --bg:   #0a0a0a;
    --fg:   #e8e8e8;
    --gold: #c9a84c;
    --gold-dim: #8a6f2e;
    --gold-bright: #e6c45c;
    --muted: #999;
    --max-width: 720px;
    --card-bg: #111;
    --card-bg-hover: #161616;
    --border: #1a1a1a;
}

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

html {
    scroll-behavior: smooth;
}

body {
    background: var(--bg);
    color: var(--fg);
    font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
    font-size: 17px;
    line-height: 1.7;
    overflow-x: hidden;
}

a {
    color: var(--gold);
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    color: var(--gold-bright);
}

/* ── Page shell (positioning context for borders) ─ */

.page-shell {
    position: relative;
    min-height: 100vh;
}

/* ── Girih border canvases ──────────────────────── */
/* Default (tablet): 150px wide */

.girih-border {
    position: absolute;
    top: 0;
    width: 150px;
    pointer-events: none;
    z-index: 0;
}

.girih-left {
    left: 0;
}

.girih-right {
    right: 0;
}

/* ── Content wrapper ────────────────────────────── */

.content-wrapper {
    position: relative;
    z-index: 1;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 2rem;
}

/* ── Navigation ─────────────────────────────────── */

.nav {
    position: sticky;
    top: 0;
    z-index: 10;
    display: flex;
    justify-content: center;
    gap: 1.8rem;
    padding: 1.2rem 0;
    font-size: 0.9rem;
    letter-spacing: 0.03em;
    background: rgba(10, 10, 10, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid #222;
}

.nav a {
    color: var(--muted);
    text-transform: uppercase;
    font-weight: 500;
    position: relative;
    padding-bottom: 2px;
    transition: color 0.25s;
}

.nav a::after {
    content: '';
    position: absolute;
    left: 0;
    right: 0;
    bottom: -2px;
    height: 1.5px;
    background: var(--gold);
    transform: scaleX(0);
    transition: transform 0.25s ease;
}

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

.nav a:hover::after {
    transform: scaleX(1);
}

.nav a.active {
    color: var(--gold);
}

.nav a.active::after {
    transform: scaleX(1);
}

/* ── Hero ───────────────────────────────────────── */

.hero {
    padding: 5rem 0 3rem;
}

.hero-inner {
    display: flex;
    align-items: center;
    gap: 2.5rem;
}

.photo {
    width: 280px;
    height: 280px;
    border-radius: 12px;
    border: 2px solid var(--gold-dim);
    object-fit: cover;
    object-position: center 12%;
    flex-shrink: 0;
    transition: border-color 0.4s;
}

.photo:hover {
    border-color: var(--gold);
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.1;
}

.tagline {
    color: var(--gold);
    font-size: 1.15rem;
    margin-top: 0.5rem;
    font-weight: 500;
}

.affiliation {
    color: var(--muted);
    font-size: 0.95rem;
    margin-top: 0.3rem;
}

/* ── Sections ───────────────────────────────────── */

.section {
    padding: 3.5rem 0;
    border-top: 1px solid var(--border);
}

h2 {
    font-size: 1.4rem;
    font-weight: 600;
    color: var(--gold);
    margin-bottom: 1.5rem;
    letter-spacing: 0.01em;
}

.section p {
    margin-bottom: 1rem;
}

.section-note {
    color: var(--muted);
    font-size: 0.9rem;
}

/* ── Research grid ──────────────────────────────── */

.research-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
}

.research-card {
    padding: 1.5rem;
    background: var(--card-bg);
    border-left: 3px solid var(--gold-dim);
    border-radius: 0 6px 6px 0;
    transition: background 0.3s, border-color 0.3s, transform 0.3s;
}

.research-card:hover {
    background: var(--card-bg-hover);
    border-left-color: var(--gold);
    transform: translateX(4px);
}

.research-card h3 {
    font-size: 1.05rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--fg);
}

.research-card p {
    font-size: 0.95rem;
    color: #bbb;
    margin-bottom: 0;
}

/* ── Publications ───────────────────────────────── */

.pub-list {
    display: flex;
    flex-direction: column;
    gap: 0;
}

.pub {
    display: flex;
    flex-direction: column;
    gap: 0.15rem;
    padding: 0.9rem 1rem;
    border-radius: 6px;
    transition: background 0.25s;
}

.pub:hover {
    background: var(--card-bg);
}

.pub-title {
    font-weight: 600;
    font-size: 1rem;
}

.pub-detail {
    font-size: 0.88rem;
    color: var(--muted);
}

/* ── Timeline ───────────────────────────────────── */

.timeline {
    position: relative;
    display: flex;
    flex-direction: column;
    gap: 1.4rem;
    padding-left: 0;
}

/* Vertical connecting line */
.timeline::before {
    content: '';
    position: absolute;
    left: 5.1rem;
    top: 0.5rem;
    bottom: 0.5rem;
    width: 1px;
    background: linear-gradient(to bottom, var(--gold-dim), var(--border));
}

.timeline-item {
    display: flex;
    gap: 1.5rem;
    align-items: baseline;
    position: relative;
}

/* Dot on the timeline */
.timeline-item::before {
    content: '';
    position: absolute;
    left: 4.85rem;
    top: 0.55rem;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--gold-dim);
    transition: background 0.25s;
}

.timeline-item:hover::before {
    background: var(--gold);
}

.timeline-date {
    flex-shrink: 0;
    width: 4.2rem;
    font-size: 0.85rem;
    color: var(--gold-dim);
    font-variant-numeric: tabular-nums;
    text-align: right;
}

.timeline-content {
    padding-left: 1rem;
}

.timeline-item strong {
    color: var(--fg);
}

.timeline-detail {
    color: var(--muted);
    font-size: 0.9rem;
}

/* ── Contact ────────────────────────────────────── */

.contact-links {
    font-size: 1.05rem;
}

.contact-links a {
    transition: color 0.2s;
}

.sep {
    color: #333;
    margin: 0 0.3rem;
}

/* ── Footer ─────────────────────────────────────── */

footer {
    padding: 3rem 0 2rem;
    border-top: 1px solid var(--border);
    text-align: center;
    color: #444;
    font-size: 0.8rem;
}

/* ── Responsive ─────────────────────────────────── */

@media (max-width: 640px) {
    body {
        font-size: 16px;
    }

    .content-wrapper {
        padding: 0 2.8rem;
    }

    .nav {
        gap: 1rem;
        flex-wrap: wrap;
        font-size: 0.8rem;
    }

    .hero {
        padding: 3rem 0 2rem;
    }

    .hero-inner {
        flex-direction: column;
        text-align: center;
        gap: 1.5rem;
    }

    h1 {
        font-size: 2rem;
    }

    .photo {
        width: 200px;
        height: 200px;
    }

    .timeline::before {
        display: none;
    }

    .timeline-item::before {
        display: none;
    }

    .timeline-item {
        flex-direction: column;
        gap: 0.2rem;
    }

    .timeline-date {
        text-align: left;
        width: auto;
    }

    .timeline-content {
        padding-left: 0;
    }

    .research-card:hover {
        transform: none;
    }

    .girih-border {
        width: 30px;
    }
}

@media (min-width: 900px) {
    /* Scale with viewport so borders always reach near the content.
       Content is 720px centred, so each side gap ≈ (100vw - 720px) / 2.
       We use calc to fill most of that gap. */
    .girih-border {
        width: calc((100vw - 720px) / 2 - 1rem);
        min-width: 120px;
        max-width: 600px;
    }
}