/* CREATE Lab — Dr. Tameshwer Nath · Academic design system */

:root {
    --navy: #0a2540;
    --charcoal: #24292f;
    --muted: #57606a;
    --accent: #0d7a83;
    --accent-light: #e6f2f3;
    --bg: #fafaf9;
    --bg-white: #ffffff;
    --border: #e5e5e2;
    --border-dark: #d0d7de;
}

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

html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg);
    color: var(--charcoal);
    line-height: 1.65;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.container { max-width: 1100px; margin: 0 auto; padding: 0 1.5rem; }

/* ---------- Typography ---------- */

.eyebrow {
    display: block;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 0.5rem;
}

h1 { font-size: clamp(2rem, 5vw, 3rem); font-weight: 700; color: var(--navy); line-height: 1.15; letter-spacing: -0.02em; }
h2 { font-size: 1.75rem; font-weight: 700; color: var(--navy); letter-spacing: -0.01em; }
h3 { font-size: 1.15rem; font-weight: 600; color: var(--navy); }
h4 { font-size: 1rem; font-weight: 600; color: var(--navy); }

.page-header { padding: 3.5rem 0 2.5rem; border-bottom: 1px solid var(--border); }
.page-header p.lead { margin-top: 0.75rem; max-width: 46rem; color: var(--muted); font-size: 1.05rem; }

.section { padding: 3rem 0; }
.section + .section { border-top: 1px solid var(--border); }
.section-head { margin-bottom: 1.75rem; }

.text-muted { color: var(--muted); }
.small { font-size: 0.875rem; }

/* ---------- Header / Nav ---------- */

.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.96);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--border);
}

.site-header .container {
    max-width: 1320px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 0.5rem;
    padding-top: 0.6rem;
    padding-bottom: 0.6rem;
    min-height: 4rem;
}

.brand { display: flex; align-items: center; gap: 0.65rem; }
.brand img { width: 2.5rem; height: 2.5rem; border-radius: 50%; object-fit: cover; flex-shrink: 0; }
.brand .brand-name { font-weight: 700; color: var(--navy); font-size: 0.95rem; line-height: 1.25; white-space: nowrap; }
.brand .brand-sub { font-size: 0.72rem; color: var(--muted); white-space: nowrap; }

.main-nav { display: flex; align-items: center; gap: 0.1rem; flex-wrap: wrap; }
.main-nav a {
    padding: 0.4rem 0.5rem;
    font-size: 0.85rem;
    color: var(--charcoal);
    border-radius: 6px;
    white-space: nowrap;
}
.main-nav a:hover { color: var(--navy); background: var(--accent-light); text-decoration: none; }
.main-nav a.active { color: var(--accent); font-weight: 600; }
.main-nav a.nav-cv {
    margin-left: 0.35rem;
    border: 1px solid var(--accent);
    color: var(--accent);
    font-weight: 600;
    padding: 0.4rem 0.75rem;
}
.main-nav a.nav-cv:hover { background: var(--accent); color: #fff; }

.nav-toggle {
    display: none;
    background: none;
    border: 1px solid var(--border-dark);
    border-radius: 6px;
    padding: 0.4rem 0.6rem;
    font-size: 1.1rem;
    color: var(--navy);
    cursor: pointer;
}

/* Mobile drawer */
.mobile-nav { display: none; border-bottom: 1px solid var(--border); background: #fff; }
.mobile-nav.open { display: block; }
.mobile-nav ul { list-style: none; padding: 0.5rem 1.5rem 1rem; }
.mobile-nav a {
    display: block;
    padding: 0.6rem 0.25rem;
    color: var(--charcoal);
    border-bottom: 1px solid var(--border);
    font-size: 0.95rem;
}
.mobile-nav a.active { color: var(--accent); font-weight: 600; }
.mobile-nav a.nav-cv { color: var(--accent); font-weight: 700; }

@media (max-width: 1100px) {
    .main-nav { display: none; }
    .nav-toggle { display: inline-block; }
}

/* ---------- Footer ---------- */

.site-footer {
    background: var(--navy);
    color: #c9d4de;
    margin-top: 3rem;
}
.site-footer .footer-inner {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 2rem;
    padding: 3rem 0;
}
.site-footer h4 { color: #fff; margin-bottom: 0.75rem; font-size: 0.95rem; }
.site-footer a { color: #c9d4de; }
.site-footer a:hover { color: #fff; }
.site-footer ul { list-style: none; }
.site-footer li { margin-bottom: 0.4rem; }
.site-footer .footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.15);
    padding: 1.25rem 0;
    font-size: 0.85rem;
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 0.5rem;
}
@media (max-width: 720px) {
    .site-footer .footer-inner { grid-template-columns: 1fr; gap: 1.5rem; }
}

/* ---------- Buttons ---------- */

.btn {
    display: inline-block;
    padding: 0.65rem 1.25rem;
    font-size: 0.925rem;
    font-weight: 600;
    border-radius: 8px;
    border: 1px solid transparent;
    transition: background 0.15s ease, color 0.15s ease;
    cursor: pointer;
}
.btn:hover { text-decoration: none; }

.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: #0a636b; }

.btn-outline { border-color: var(--navy); color: var(--navy); background: transparent; }
.btn-outline:hover { background: var(--navy); color: #fff; }

.btn-ghost { border-color: var(--border-dark); color: var(--charcoal); background: transparent; }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }

.btn-sm { padding: 0.4rem 0.85rem; font-size: 0.85rem; }

/* ---------- Hero ---------- */

.hero { border-bottom: 1px solid var(--border); background: var(--bg-white); }
.hero .container {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 3rem;
    align-items: center;
    padding-top: 4.5rem;
    padding-bottom: 4.5rem;
}
.hero .hero-role { color: var(--muted); font-size: 1.05rem; margin: 0.5rem 0 0.25rem; }
.hero .hero-lab { margin: 1.5rem 0; padding: 1rem 1.25rem; border-left: 3px solid var(--accent); background: var(--bg); }
.hero .hero-lab strong { color: var(--navy); }
.hero .hero-statement { max-width: 40rem; color: var(--charcoal); }
.hero .hero-actions { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-top: 1.75rem; }
.hero .profile-photo {
    width: 220px;
    height: 220px;
    border-radius: 50%;
    object-fit: cover;
    border: 1px solid var(--border-dark);
}
@media (max-width: 720px) {
    .hero .container { grid-template-columns: 1fr; }
    .hero .profile-photo { width: 160px; height: 160px; }
}

/* ---------- Stats ---------- */

.stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 1px; background: var(--border); border: 1px solid var(--border); }
.stat { background: var(--bg-white); padding: 1.5rem 1rem; text-align: center; }
.stat .stat-num { font-size: 2rem; font-weight: 700; color: var(--navy); line-height: 1.1; }
.stat .stat-label { font-size: 0.8rem; color: var(--muted); margin-top: 0.25rem; }

/* ---------- Cards ---------- */

.grid-2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 1.25rem; }
.grid-3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1.25rem; }
.grid-4 { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 1.25rem; }

.card {
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 1.5rem;
}
.card h3 { margin-bottom: 0.5rem; }

.area-card { display: flex; flex-direction: column; gap: 0.5rem; }
.area-card .area-num { font-size: 0.8rem; font-weight: 700; color: var(--accent); letter-spacing: 0.08em; }
.area-card p { color: var(--muted); font-size: 0.95rem; }

.feature-card { padding: 0; overflow: hidden; display: flex; flex-direction: column; }
.feature-card img { width: 100%; height: 200px; object-fit: cover; border-bottom: 1px solid var(--border); }
.feature-card .feature-body { padding: 1.25rem 1.5rem; }

/* ---------- Badges ---------- */

.badge {
    display: inline-block;
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    padding: 0.2rem 0.55rem;
    border-radius: 5px;
    border: 1px solid var(--border-dark);
    color: var(--muted);
    background: var(--bg);
}
.badge-sci { color: var(--accent); border-color: var(--accent); background: var(--accent-light); }
.badge-granted { color: #1a7f37; border-color: #1a7f37; background: #eaf6ec; }
.badge-exam { color: #9a6700; border-color: #9a6700; background: #fff8c5; }
.badge-year { float: right; }

/* ---------- Publications ---------- */

.filter-tabs { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-bottom: 1.5rem; }
.filter-tabs button {
    padding: 0.45rem 0.95rem;
    border: 1px solid var(--border-dark);
    background: var(--bg-white);
    border-radius: 999px;
    font-size: 0.875rem;
    color: var(--muted);
    cursor: pointer;
}
.filter-tabs button:hover { border-color: var(--accent); color: var(--accent); }
.filter-tabs button.active { background: var(--navy); border-color: var(--navy); color: #fff; }

.year-group { margin-bottom: 2rem; }
.year-group h3 {
    display: flex;
    align-items: center;
    gap: 1rem;
    font-size: 1.3rem;
    margin-bottom: 1rem;
}
.year-group h3::after { content: ''; flex: 1; height: 1px; background: var(--border); }

.pub-card {
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-left: 3px solid var(--accent);
    border-radius: 8px;
    padding: 1.1rem 1.4rem;
    margin-bottom: 0.9rem;
}
.pub-card .pub-title { font-weight: 600; color: var(--navy); }
.pub-card .pub-authors { color: var(--muted); font-size: 0.9rem; margin-top: 0.3rem; }
.pub-card .pub-venue { margin-top: 0.35rem; font-size: 0.95rem; }
.pub-card .pub-meta { margin-top: 0.5rem; display: flex; flex-wrap: wrap; align-items: center; gap: 0.6rem; font-size: 0.85rem; color: var(--muted); }
.pub-card .pub-meta a { font-weight: 600; }

/* ---------- Timeline ---------- */

.timeline { position: relative; padding-left: 1.75rem; }
.timeline::before {
    content: '';
    position: absolute;
    left: 5px;
    top: 0.4rem;
    bottom: 0.4rem;
    width: 1px;
    background: var(--border-dark);
}
.timeline-item { position: relative; padding-bottom: 1.75rem; }
.timeline-item::before {
    content: '';
    position: absolute;
    left: -1.75rem;
    top: 0.45rem;
    width: 11px;
    height: 11px;
    border-radius: 50%;
    background: var(--bg);
    border: 2px solid var(--accent);
}
.timeline-item .t-date { font-size: 0.8rem; font-weight: 700; color: var(--accent); letter-spacing: 0.04em; text-transform: uppercase; }
.timeline-item .t-title { font-weight: 600; color: var(--navy); margin-top: 0.15rem; }
.timeline-item .t-sub { color: var(--muted); font-size: 0.95rem; }
.timeline-item .t-note { color: var(--muted); font-size: 0.875rem; margin-top: 0.25rem; }
.timeline-item:last-child { padding-bottom: 0; }

/* ---------- Tables ---------- */

.table-wrap { overflow-x: auto; }
table.data {
    width: 100%;
    border-collapse: collapse;
    background: var(--bg-white);
    font-size: 0.925rem;
}
table.data th, table.data td { padding: 0.65rem 0.85rem; text-align: left; border: 1px solid var(--border); vertical-align: top; }
table.data th { background: var(--bg); color: var(--navy); font-weight: 600; white-space: nowrap; }

/* ---------- People ---------- */

.person-card { text-align: center; }
.person-card img {
    width: 110px;
    height: 110px;
    border-radius: 50%;
    object-fit: cover;
    margin: 0 auto 0.75rem;
    border: 1px solid var(--border-dark);
}
.person-card .person-name { font-weight: 700; color: var(--navy); }
.person-card .person-role { font-size: 0.85rem; color: var(--accent); font-weight: 600; }
.person-card .person-topic { font-size: 0.875rem; color: var(--muted); margin-top: 0.4rem; }

.pi-card { display: grid; grid-template-columns: 180px 1fr; gap: 2rem; align-items: start; }
.pi-card img { width: 180px; height: 180px; border-radius: 10px; object-fit: cover; border: 1px solid var(--border-dark); }
.pi-card .pi-links { display: flex; flex-wrap: wrap; gap: 0.6rem; margin-top: 1rem; }
@media (max-width: 640px) {
    .pi-card { grid-template-columns: 1fr; }
    .pi-card img { width: 140px; height: 140px; }
}

/* ---------- Patent / project detail ---------- */

.detail-grid { display: grid; grid-template-columns: 170px 1fr; gap: 0.4rem 1rem; font-size: 0.925rem; }
.detail-grid dt { color: var(--muted); font-weight: 600; }
.detail-grid dd { color: var(--charcoal); }
@media (max-width: 560px) {
    .detail-grid { grid-template-columns: 1fr; gap: 0.1rem 0; }
    .detail-grid dt { margin-top: 0.5rem; }
}

/* ---------- News ---------- */

.news-list { list-style: none; }
.news-list li {
    display: grid;
    grid-template-columns: 90px 1fr;
    gap: 1rem;
    padding: 0.9rem 0;
    border-bottom: 1px solid var(--border);
}
.news-list .news-date { font-weight: 700; color: var(--accent); font-size: 0.875rem; }
.news-list li:last-child { border-bottom: none; }

/* ---------- Collapsible ---------- */

details.earlier { border: 1px solid var(--border); border-radius: 10px; background: var(--bg-white); padding: 1rem 1.5rem; }
details.earlier summary { cursor: pointer; font-weight: 600; color: var(--navy); }
details.earlier[open] summary { margin-bottom: 1rem; }

/* ---------- Video ---------- */

.video-wrap { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; border-radius: 10px; border: 1px solid var(--border); }
.video-wrap video, .video-wrap iframe { position: absolute; top: 0; left: 0; width: 100%; height: 100%; }

/* ---------- Utility ---------- */

.mt-1 { margin-top: 0.5rem; } .mt-2 { margin-top: 1rem; } .mt-3 { margin-top: 1.5rem; } .mt-4 { margin-top: 2rem; }
.mb-1 { margin-bottom: 0.5rem; } .mb-2 { margin-bottom: 1rem; } .mb-3 { margin-bottom: 1.5rem; }
.flex-row { display: flex; flex-wrap: wrap; gap: 0.75rem; align-items: center; }

.profile-links { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 1rem; }
.profile-link { display: flex; gap: 1rem; align-items: center; }
.profile-link .pl-icon { font-size: 1.4rem; color: var(--accent); width: 2rem; text-align: center; }
.profile-link .pl-name { font-weight: 600; color: var(--navy); }
.profile-link .pl-id { font-size: 0.8rem; color: var(--muted); }
.profile-link:hover { border-color: var(--accent); text-decoration: none; }