/* Portfolio — customize colors and fonts via :root */
:root {
  --ocean-deep: #0c2d48;
  --ocean-mid: #1b4965;
  --ocean-light: #62b6cb;
  --ocean-mist: #e8f4f8;
  --ocean-white: #feffff;
  --text-primary: #0f172a;
  --text-muted: #475569;
  --accent: #2a6f97;
  --accent-hover: #1f5a7a;
  --shadow-sm: 0 2px 8px rgba(12, 45, 72, 0.08);
  --shadow-md: 0 8px 24px rgba(12, 45, 72, 0.12);
  --radius: 12px;
  --radius-lg: 18px;
  --transition: 0.25s ease;
  --max-width: 900px;
  --nav-height: 4rem;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 1.05rem;
  line-height: 1.65;
  color: var(--text-primary);
  background: linear-gradient(180deg, var(--ocean-mist) 0%, var(--ocean-white) 35%, #f0f9fc 100%);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

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

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

/* Skip link */
.skip-link {
  position: absolute;
  left: -9999px;
  z-index: 999;
  padding: 0.5rem 1rem;
  background: var(--ocean-deep);
  color: var(--ocean-white);
}

.skip-link:focus {
  left: 1rem;
  top: 1rem;
}

/* Header & nav */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(254, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(27, 73, 101, 0.08);
  box-shadow: var(--shadow-sm);
}

.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.25rem;
  height: var(--nav-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.logo {
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--ocean-deep);
  letter-spacing: -0.02em;
  transition: opacity var(--transition);
}

.logo:hover {
  opacity: 0.85;
  color: var(--ocean-mid);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  padding: 0.5rem;
  cursor: pointer;
  color: var(--ocean-deep);
}

.nav-toggle:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.nav-toggle-icon {
  display: block;
  width: 24px;
  height: 2px;
  background: currentColor;
  position: relative;
}

.nav-toggle-icon::before,
.nav-toggle-icon::after {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  background: currentColor;
  transition: transform var(--transition);
}

.nav-toggle-icon::before {
  top: -7px;
}

.nav-toggle-icon::after {
  top: 7px;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-menu a {
  display: block;
  padding: 0.5rem 0.85rem;
  border-radius: 8px;
  color: var(--text-muted);
  font-weight: 500;
  font-size: 0.95rem;
}

.nav-menu a:hover {
  color: var(--ocean-deep);
  background: rgba(98, 182, 203, 0.12);
}

.nav-menu a.active {
  color: var(--ocean-deep);
  background: rgba(27, 73, 101, 0.08);
}

/* Main */
main {
  flex: 1;
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2.5rem 1.25rem 4rem;
}

.page-title {
  font-size: clamp(1.75rem, 4vw, 2.25rem);
  font-weight: 600;
  color: var(--ocean-deep);
  letter-spacing: -0.03em;
  margin: 0 0 0.5rem;
}

.page-subtitle {
  font-size: 1.1rem;
  color: var(--accent);
  font-weight: 500;
  margin: 0 0 2rem;
}

/* Home hero */
.hero {
  padding: 1rem 0 2rem;
  animation: fadeUp 0.6s ease forwards;
  text-align: center;
}

.hero-photo-wrap {
  margin: 0.85rem auto 1.1rem;
  width: fit-content;
  max-width: 100%;
}

.hero-photo {
  width: min(240px, 72vw);
  height: min(240px, 72vw);
  max-width: none;
  margin: 0 auto;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid rgba(98, 182, 203, 0.4);
  box-shadow:
    0 12px 32px rgba(12, 45, 72, 0.16),
    0 4px 12px rgba(12, 45, 72, 0.1);
  transition: transform var(--transition), box-shadow var(--transition);
}

.hero-photo-wrap:hover .hero-photo {
  transform: scale(1.03);
  box-shadow:
    0 16px 40px rgba(12, 45, 72, 0.2),
    0 6px 16px rgba(98, 182, 203, 0.22);
}

@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.hero-name {
  font-size: clamp(2rem, 5vw, 2.75rem);
  font-weight: 700;
  color: var(--ocean-deep);
  letter-spacing: -0.03em;
  margin: 0 0 0.25rem;
  line-height: 1.15;
}

.hero-role {
  font-size: 1.15rem;
  color: var(--ocean-mid);
  font-weight: 500;
  margin: 0 0 1.5rem;
}

.hero-intro {
  max-width: 38rem;
  margin: 0 auto 2rem;
  color: var(--text-muted);
}

.social-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
}

.social-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1.1rem;
  background: var(--ocean-white);
  border: 1px solid rgba(27, 73, 101, 0.12);
  border-radius: var(--radius);
  color: var(--ocean-mid);
  font-weight: 500;
  font-size: 0.95rem;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

.social-link:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: rgba(42, 111, 151, 0.35);
  color: var(--accent);
}

.social-link svg {
  flex-shrink: 0;
  opacity: 0.85;
}

/* Sections (About) */
.content-section {
  margin-bottom: 2.75rem;
}

.content-section:last-child {
  margin-bottom: 0;
}

.section-heading {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--ocean-deep);
  margin: 0 0 1rem;
  padding-bottom: 0.4rem;
  border-bottom: 2px solid rgba(98, 182, 203, 0.45);
  display: inline-block;
}

.academic-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.academic-item {
  padding: 1rem 0;
  border-bottom: 1px solid rgba(27, 73, 101, 0.08);
}

.academic-item:last-child {
  border-bottom: none;
}

.academic-item strong {
  display: block;
  color: var(--text-primary);
  font-size: 1.02rem;
  margin-bottom: 0.25rem;
}

.academic-meta {
  font-size: 0.95rem;
  color: var(--text-muted);
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.tag {
  display: inline-block;
  padding: 0.35rem 0.75rem;
  background: rgba(98, 182, 203, 0.2);
  color: var(--ocean-mid);
  border-radius: 999px;
  font-size: 0.9rem;
  font-weight: 500;
  transition: background var(--transition), transform var(--transition);
}

.tag:hover {
  background: rgba(42, 111, 151, 0.15);
  transform: translateY(-1px);
}

.personal-note {
  background: rgba(254, 255, 255, 0.85);
  border-left: 4px solid var(--ocean-light);
  padding: 1.25rem 1.35rem;
  border-radius: 0 var(--radius) var(--radius) 0;
  color: var(--text-muted);
  box-shadow: var(--shadow-sm);
}

/* Project cards */
.projects-grid {
  display: grid;
  gap: 2rem;
}

.project-card {
  background: var(--ocean-white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid rgba(27, 73, 101, 0.1);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition);
}

.project-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}

.project-card-image {
  aspect-ratio: 16 / 9;
  background: linear-gradient(135deg, var(--ocean-mist) 0%, #d4eaf2 100%);
  overflow: hidden;
}

.project-card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.project-card-body {
  padding: 1.35rem 1.5rem 1.5rem;
}

.project-card-title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--ocean-deep);
  margin: 0 0 0.35rem;
}

.project-card-meta {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin: 0 0 0.75rem;
}

.project-location {
  font-size: 0.88rem;
  color: var(--accent);
  font-weight: 500;
  margin: 0 0 1rem;
}

.project-subsection {
  margin-top: 1.15rem;
}

.project-subsection:first-of-type {
  margin-top: 0.5rem;
}

.project-subsection h4 {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--ocean-mid);
  margin: 0 0 0.5rem;
}

.project-card ul {
  margin: 0;
  padding-left: 1.2rem;
  color: var(--text-muted);
}

.project-card li {
  margin-bottom: 0.35rem;
}

.project-card li:last-child {
  margin-bottom: 0;
}

/* Publications placeholder */
.placeholder-box {
  text-align: center;
  padding: 3rem 1.5rem;
  background: rgba(255, 255, 255, 0.7);
  border: 1px dashed rgba(27, 73, 101, 0.25);
  border-radius: var(--radius-lg);
  color: var(--text-muted);
}

/* Contact */
.contact-lead {
  color: var(--text-muted);
  max-width: 36rem;
  margin: 0 0 1.5rem;
}

.email-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.1rem;
  font-weight: 600;
  padding: 0.75rem 1.25rem;
  background: var(--ocean-deep);
  color: var(--ocean-white) !important;
  border-radius: var(--radius);
  transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
}

.email-link:hover {
  background: var(--ocean-mid);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.contact-email-wrap {
  margin: 0 0 0.25rem;
}

.contact-social {
  margin-top: 2rem;
  max-width: 36rem;
}

/* Align social buttons with Contact body text; Home hero uses default centered .social-row */
.contact-social-row {
  justify-content: flex-start;
}

/* Footer */
.site-footer {
  margin-top: auto;
  padding: 1.5rem 1.25rem;
  text-align: center;
  font-size: 0.9rem;
  color: var(--text-muted);
  border-top: 1px solid rgba(27, 73, 101, 0.08);
  background: rgba(232, 244, 248, 0.5);
}

/* Mobile nav */
@media (max-width: 768px) {
  .contact-social-row {
    justify-content: center;
  }

  .nav-toggle {
    display: block;
  }

  .nav-menu {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    padding: 1rem;
    background: rgba(254, 255, 255, 0.98);
    border-bottom: 1px solid rgba(27, 73, 101, 0.1);
    box-shadow: var(--shadow-md);
    gap: 0.25rem;
    transform: translateY(-120%);
    opacity: 0;
    visibility: hidden;
    transition: transform var(--transition), opacity var(--transition), visibility var(--transition);
  }

  .nav-menu.is-open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .nav-menu a {
    padding: 0.75rem 1rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}