/* ===============================
   Minimalist Design Token Overrides
   =============================== */
@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Sans:wght@300;400;600;700&display=swap');

:root {
  /* Minimal, muted dark theme (default) */
  --color-bg: #111111;                /* page background */
  --color-primary: #111111;
  --color-bg-light: #141414;
  --color-bg-lighter: #181818;
  --color-text-primary: #f5f5f5;      /* higher contrast for readability */
  --color-text-secondary: #b3b3b3;    /* readable secondary text */
  --color-border: rgba(255,255,255,0.06);
  --color-shadow: rgba(2,6,23,0.06);

  /* Accent - muted gray for minimalist look */
  --color-accent: #9CA3AF;       /* gray-400 */
  --color-accent-secondary: #6B7280; /* gray-500 */

  /* Light theme values live under [data-theme="light"] */

  /* Typography */
  --font-family: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, sans-serif;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.5rem;
  --font-size-xxl: 2rem;

  /* Spacing */
  --spacing-xs: 0.375rem;
  --spacing-sm: 0.75rem;
  --spacing-md: 1.25rem;
  --spacing-lg: 1.75rem;
  --spacing-xl: 2.5rem;
  --spacing-xxl: 3.5rem;

  /* Border Radius - small & subtle */
  --radius-sm: 8px;
  --radius-md: 10px;
  --radius-lg: 12px;

  /* Transitions */
  --transition: color 0.15s ease, background-color 0.2s ease, transform 0.18s ease;
}

/* Light Mode Theme */
[data-theme="light"] {
  --color-bg: #fafafa;
  --color-primary: #fafafa;
  --color-bg-light: #f5f5f5;
  --color-bg-lighter: #ededed;
  --color-text-primary: #111111;
  --color-text-secondary: #4b4b4b;
  --color-border: rgba(17,17,17,0.08);
  --color-shadow: rgba(2,6,23,0.03);
  --color-accent: #2563EB;
  --color-accent-secondary: #1D4ED8;
}

/* ===============================
   Base Styles
   =============================== */
* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  margin: 0;
  padding: 0;
  background-color: var(--color-bg);
  line-height: 1.6;
  color: var(--color-text-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Global heading styles for a minimalist, consistent look */
h1, h2, h3, h4 {
  font-family: var(--font-family);
  color: var(--color-text-primary);
  margin: 0 0 var(--spacing-sm) 0;
  font-weight: 600;
}

h2 {
  font-size: 1.1rem;
  font-weight: 600;
}

h3 {
  font-size: 1rem;
  font-weight: 600;
}

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

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

/* ===============================
   Header / Navigation
   =============================== */
header {
  color: var(--color-text-primary);
  padding: calc(var(--spacing-sm) - 2px) var(--spacing-md);
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid var(--color-border);
  background-color: var(--color-bg);
  backdrop-filter: blur(8px);
  transition: var(--transition);
}

[data-theme="light"] header {
  background-color: rgba(248, 250, 252, 0.95);
  border-bottom-color: var(--color-border);
}

nav {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  max-width: 1400px;
  margin: 0 auto;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  flex: 1;
}

nav a {
  color: var(--color-text-primary);
  font-weight: 500;
  transition: var(--transition);
  position: relative;
}

nav a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-accent);
  transition: width 0.3s ease;
}

nav a:hover::after {
  width: 100%;
}

nav .logo {
  font-weight: 700;
  font-size: 1.15rem;
  margin-right: 0;
  color: var(--color-text-primary);
  letter-spacing: -0.01em;
}

#menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--color-text-primary);
  font-size: 1.5rem;
  cursor: pointer;
  width: auto;
  height: auto;
  padding: 0;
  margin: 0 0 0 auto;
  transition: var(--transition);
}

#menu-toggle:hover {
  color: var(--color-accent);
}

.nav-links.open {
  position: fixed;
  top: 60px;
  left: 0;
  right: 0;
  width: 100vw;
  flex-direction: column;
  gap: 0;
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding: var(--spacing-md);
  align-items: flex-start;
  z-index: 99;
  margin-left: 0;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.nav-links.open a {
  display: block;
  padding: var(--spacing-sm) 0;
  width: 100%;
  border-bottom: 1px solid var(--color-border);
}

#theme-toggle {
  background: none;
  border: 2px solid var(--color-border);
  color: var(--color-text-primary);
  width: 40px;
  height: 40px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
  font-size: 1.2rem;
}

#theme-toggle:hover {
  border-color: var(--color-accent);
  box-shadow: none;
}

/* ===============================
   Main Content
   =============================== */
main {
  padding: var(--spacing-lg) var(--spacing-sm);
  max-width: 1400px;
  margin: 0 auto;
}

main h1 {
  text-align: center;
  font-size: 2.25rem;
  margin-bottom: var(--spacing-lg);
  font-weight: 700;
  color: var(--color-text-primary);
  letter-spacing: -0.02em;
  line-height: 1.05;
}

.content-wrapper {
  max-width: 1000px;
  margin: var(--spacing-lg) auto;
  padding: 0 var(--spacing-sm);
  line-height: 1.7;
  color: var(--color-text-primary);
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: var(--spacing-xl);
  align-items: center;
}

/* ===============================
   About Page (Minimal)
   =============================== */
.content-wrapper-about {
  max-width: 750px;
  margin: var(--spacing-lg) auto;
  padding: 0 var(--spacing-sm);
  line-height: 1.7;
  color: var(--color-text-primary);
}

.about-header {
  margin-bottom: var(--spacing-xxl);
}

.about-header h1 {
  font-size: var(--font-size-xxl);
  margin-bottom: var(--spacing-md);
  color: var(--color-text-primary);
  font-weight: 700;
}

.about-header p {
  font-size: 1rem;
  color: var(--color-text-primary);
  line-height: 1.8;
}

.bio-subtitle {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  margin-top: var(--spacing-xs);
}

.bio-content p {
  margin: 0 0 var(--spacing-lg) 0;
  color: var(--color-text-primary);
}

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

.about-section-card {
  margin-bottom: var(--spacing-xxl);
}

.about-section-card h2 {
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-lg);
  color: var(--color-accent);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* About Lists */
.about-list {
  margin: 0;
  padding-left: 1.1rem;
  color: var(--color-text-primary);
  display: grid;
  gap: var(--spacing-sm);
}

.about-list strong {
  font-weight: 600;
  color: var(--color-text-primary);
}

/* Links Page */
.links-section {
  margin-bottom: var(--spacing-xxl);
}

.links-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: var(--spacing-sm);
}

.links-list a {
  color: var(--color-text-primary);
  text-decoration: none;
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 2px;
  transition: var(--transition);
}

.links-list a:hover {
  color: var(--color-accent);
  border-color: var(--color-accent);
}

.links-note {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
  margin-top: var(--spacing-md);
}

.about-section {
  max-width: 900px;
  margin: var(--spacing-lg) auto;
  padding: 0 var(--spacing-sm);
  line-height: 1.7;
  color: var(--color-text-primary);
}

.about-section h1 {
  text-align: center;
  margin-bottom: var(--spacing-lg);
  font-size: var(--font-size-xl);
  color: var(--color-text-primary);
  font-weight: 700;
}

.about-section p {
  margin-bottom: var(--spacing-md);
  color: var(--color-text-primary);
}

.about-section a {
  color: var(--color-accent);
  text-decoration: underline;
  transition: var(--transition);
}

.about-section a:hover {
  color: var(--color-accent-secondary);
}

/* ===============================
   Social Links (Unified - Fixed Visibility)
   =============================== */
.social-links {
  display: flex;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-sm);
  flex-wrap: wrap;
}

.social-links a {
  color: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 2px solid var(--color-border);
  transition: var(--transition);
  background-color: transparent;
}

.social-links a:hover {
  transform: translateY(-3px) scale(1.1);
  border-color: var(--color-accent);
  background-color: rgba(156, 163, 175, 0.08);
  box-shadow: none;
}

.social-links svg {
  width: 18px;
  height: 18px;
  fill: currentColor;
}

/* Hero Social Links - Smaller icons */
#hero-social-links .social-links a {
  width: 32px;
  height: 32px;
}

#hero-social-links .social-links svg {
  width: 16px;
  height: 16px;
}

/* Footer Social Links styling */
footer .social-links a {
  color: var(--color-accent);
  border-color: variance(--color-border);
}

footer .social-links a:hover {
  border-color: var(--color-accent);
  background-color: rgba(156, 163, 175, 0.08);
  box-shadow: none;
}

/* ===============================
   Blog Cards (Revamped)
   =============================== */
.blog-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--spacing-lg);
  margin-top: var(--spacing-lg);
}

.blog-card {
  display: flex;
  flex-direction: column;
  background-color: var(--color-bg-lighter);
  border-radius: var(--radius-lg);
  box-shadow: 0 8px 32px var(--color-shadow);
  overflow: hidden;
  color: var(--color-text-primary);
  transition: var(--transition);
  border: 1px solid var(--color-border);
}

.blog-card:hover {
  transform: none;
  box-shadow: none;
  border-color: var(--color-accent);
}

.blog-image {
  width: 100%;
  height: 200px;
  background-size: cover;
  background-position: center;
  background-color: var(--color-bg);
  transition: var(--transition);
}

.blog-card:hover .blog-image {
  transform: scale(1.05);
}

.blog-content {
  padding: var(--spacing-md);
  display: flex;
  flex-direction: column;
  flex: 1;
}

.blog-category {
  display: inline-block;
  background-color: var(--color-accent);
  color: var(--color-bg);
  padding: 4px 10px;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
  width: fit-content;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.blog-card h2 {
  font-size: 1.25rem;
  font-weight: 700;
  margin: 0 0 var(--spacing-sm) 0;
  line-height: 1.3;
  color: var(--color-text-primary);
}

.blog-date {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  margin: 0 0 var(--spacing-md) 0;
  font-weight: 500;
}

.blog-description {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
  margin: 0 0 var(--spacing-md) 0;
  flex: 1;
}

.blog-card .read-more {
  display: inline-block;
  color: var(--color-accent);
  font-weight: 600;
  font-size: 0.9rem;
  margin-top: auto;
  padding-bottom: var(--spacing-sm);
  border-bottom: 2px solid transparent;
  transition: var(--transition);
}

.blog-card .read-more:hover {
  border-bottom-color: var(--color-accent);
  color: var(--color-accent-secondary);
}

#blog-placeholder {
  text-align: center;
  font-style: italic;
  color: var(--color-text-secondary);
  margin-top: var(--spacing-xl);
  padding: var(--spacing-xl);
  background-color: var(--color-bg-lighter);
  border-radius: var(--radius-md);
  border: 2px dashed var(--color-border);
}

/* ===============================
   Publications (Revamped)
   =============================== */
.research-page h1 {
  text-align: center;
  max-width: 1000px;
  margin: 0 auto var(--spacing-lg);
}

.research-interests {
  max-width: 1000px;
  margin: 0 auto var(--spacing-lg);
  text-align: left;
}

.research-interests h2 {
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-sm);
  color: var(--color-text-primary);
}

.research-interests p {
  color: var(--color-text-secondary);
  font-size: 0.95rem;
}

.research-publications {
  max-width: 1000px;
  margin: 0 auto;
}

.research-publications h2 {
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-sm);
  color: var(--color-text-primary);
}

.pub-note {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  margin: 0 0 var(--spacing-md) 0;
}

.pub-note a {
  color: var(--color-accent);
  text-decoration: underline;
}
.pub-filters {
  display: flex;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
  justify-content: flex-start;
  margin: var(--spacing-md) 0 var(--spacing-lg);
  padding: var(--spacing-md) var(--spacing-sm);
  width: fit-content;
  max-width: 100%;
  background-color: var(--color-bg-lighter);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
}

.pub-filters button {
  padding: var(--spacing-xs) var(--spacing-md);
  border: 2px solid var(--color-border);
  background: transparent;
  color: var(--color-text-secondary);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  font-weight: 500;
  font-size: 0.95rem;
}

.pub-filters button:hover,
.pub-filters button.active {
  border-color: var(--color-accent);
  background-color: rgba(156, 163, 175, 0.08);
  color: var(--color-accent);
  box-shadow: none;
}

.pub-list {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin-top: var(--spacing-lg);
}

.pub-card {
  background: transparent;
  padding: var(--spacing-sm) 0;
  border-bottom: 1px solid var(--color-border);
  border-radius: 0;
  box-shadow: none;
  transition: var(--transition);
  border: none;
  display: flex;
  gap: var(--spacing-md);
  align-items: flex-start;
}

.pub-card:hover {
  transform: none;
  box-shadow: none;
  border: none;
  padding-left: 0;
  background-color: rgba(156, 163, 175, 0.03);
}

.pub-card > div {
  flex: 1;
  min-width: 0;
}

.pub-card .pub-type {
  display: none;
}

.pub-card h3 {
  margin: 0;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-text-primary);
  line-height: 1.3;
}

.pub-card .pub-authors {
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  margin: 0;
  line-height: 1.3;
  font-weight: 400;
}

.pub-card .pub-meta {
  font-size: 0.85rem;
  color: var(--color-accent);
  margin: 0;
  text-align: center;
  font-weight: 600;
  flex-shrink: 0;
  width: 50px;
  padding-top: 2px;
}

.pub-card .pub-tags {
  display: none;
}

.pub-tag {
  display: none;
}

.pub-card a {
  color: var(--color-accent-secondary);
  font-weight: 600;
  text-decoration: none;
  font-size: 0.8rem;
  white-space: nowrap;
  transition: var(--transition);
  flex-shrink: 0;
}
}

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

#pub-placeholder {
  text-align: center;
  padding: var(--spacing-xl);
  color: var(--color-text-secondary);
  grid-column: 1 / -1;
}

/* ===============================
   Filter Buttons (Unified)
   =============================== */
.filter-btn {
  padding: var(--spacing-xs) var(--spacing-md);
  background-color: transparent;
  border: 2px solid var(--color-border);
  color: var(--color-text-primary);
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: 0.95rem;
  transition: var(--transition);
  font-weight: 500;
}

.filter-btn:hover {
  border-color: var(--color-accent);
  background-color: rgba(156, 163, 175, 0.06);
}

.filter-btn.active {
  background-color: rgba(156, 163, 175, 0.08);
  border-color: var(--color-accent);
  color: var(--color-accent);
  box-shadow: none;
}

/* ===============================
   Empty State
   =============================== */
.empty-state {
  text-align: center;
  padding: var(--spacing-xl);
  color: var(--color-text-secondary);
}

.empty-state p {
  font-size: 1.1rem;
  margin: 0;
}

/* ===============================
   Footer
   =============================== */
footer {
  background-color: var(--color-primary);
  color: var(--color-text-primary);
  padding: var(--spacing-xl) var(--spacing-sm);
  text-align: center;
  margin-top: var(--spacing-xl);
  border-top: 1px solid var(--color-border);
}

footer .footer-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-lg);
  max-width: 1200px;
  margin: 0 auto;
}

footer .footer-links {
  display: flex;
  gap: var(--spacing-lg);
  flex-wrap: wrap;
  justify-content: center;
}

footer .footer-links a {
  color: var(--color-text-secondary);
  transition: var(--transition);
}

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

footer .footer-social {
  display: flex;
  gap: var(--spacing-sm);
  justify-content: center;
}

footer p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--color-text-secondary);
}

/* ===============================
   Hero Section
   =============================== */
.hero {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-lg);
  margin-bottom: 0;
  padding: 0;
  text-align: center;
}

.hero-text {
  flex: 0 0 auto;
}

.hero-text h1 {
  font-size: var(--font-size-xxl);
  margin-bottom: var(--spacing-xs);
  text-align: center;
  color: var(--color-text-primary);
  font-weight: 700;
}

.hero-text h2 {
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-md);
  font-weight: 500;
  color: var(--color-text-secondary);
}

.hero-name-local {
  font-size: 1rem;
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-xs);
  letter-spacing: 0.01em;
}

.hero-text p {
  margin-bottom: var(--spacing-md);
  color: var(--color-text-primary);
  line-height: 1.6;
}

.hero-text a {
  color: var(--color-accent);
  transition: var(--transition);
}

.hero-text a:hover {
  color: var(--color-accent-secondary);
  opacity: 0.8;
}

.hero-contact {
  margin-top: var(--spacing-lg);
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--color-border);
}

.hero-contact p {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  margin-bottom: 0;
}

.hero-contact a {
  color: var(--color-accent);
  font-weight: 600;
}

.hero-buttons {
  display: none;
}

.hero-buttons .btn {
  padding: var(--spacing-xs) 1.25rem;
  background-color: var(--color-accent);
  color: var(--color-bg);
  border-radius: var(--radius-sm);
  text-decoration: none;
  font-weight: 600;
  transition: var(--transition);
  cursor: pointer;
  border: none;
}

.hero-buttons .btn:hover {
  transform: translateY(-2px);
  box-shadow: none;
}

.hero-image {
  flex: 0 0 auto;
  text-align: center;
}

.hero-image img.profile-img {
  width: 140px;
  height: 140px;
  object-fit: cover;
  border-radius: 50%;
  display: inline-block;
  box-shadow: 0 8px 20px rgba(2,6,23,0.35);
  border: 1px solid var(--color-border);
  transition: var(--transition);
}

.hero-image img.profile-img:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 28px rgba(2,6,23,0.38);
}

/* ===============================
   Home About Section
   =============================== */
.home-about {
  margin: 0;
  padding: var(--spacing-xl) var(--spacing-lg);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: transparent;
  grid-column: 2;
}

.home-about-content {
  margin-bottom: var(--spacing-lg);
}

.home-about-content p {
  color: var(--color-text-primary);
  line-height: 1.7;
  margin: 0 0 var(--spacing-lg) 0;
  font-size: 0.95rem;
}

.home-about-content p:last-child {
  margin-bottom: 0;
}

.home-about-footer {
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--color-border);
  color: var(--color-text-secondary);
  font-size: 0.9rem;
}

.home-about-footer a {
  color: var(--color-accent);
  font-weight: 600;
  text-decoration: none;
  transition: var(--transition);
}

.home-about-footer a:hover {
  color: var(--color-accent-secondary);
  text-decoration: underline;
}

/* Social Section */
#social {
  margin: var(--spacing-lg) 0;
  text-align: center;
  padding: var(--spacing-lg);
  background: transparent;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  transition: var(--transition);
}

#social h3 {
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-lg);
  color: var(--color-text-primary);
}

#social .social-links {
  justify-content: center;
}

/* Section Container */
.section-container {
  margin: var(--spacing-lg) 0;
}

.section-container h3 {
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-sm);
  text-align: center;
  color: var(--color-text-primary);
}

/* ===============================
   Albums Gallery (Revamped)
   =============================== */
.albums-section {
  margin: var(--spacing-xl) 0;
}

.albums-section h1 {
  text-align: center;
  font-size: var(--font-size-xxl);
  margin-bottom: var(--spacing-lg);
  color: var(--color-text-primary);
}

.albums-filters {
  display: flex;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: var(--spacing-xl);
  padding: var(--spacing-lg);
  background-color: var(--color-bg-lighter);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
}

.albums-filters .filter-label {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.albums-filters .filter-tag {
  display: inline-flex;
  align-items: center;
  padding: var(--spacing-xs) var(--spacing-md);
  background: transparent;
  border: 2px solid var(--color-border);
  color: var(--color-text-secondary);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  font-weight: 500;
}

.albums-filters .filter-tag:hover,
.albums-filters .filter-tag.active {
  border-color: var(--color-accent);
  background-color: rgba(156, 163, 175, 0.08);
  color: var(--color-accent);
}

.albums-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

.photo-card {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-lg);
  aspect-ratio: 1;
  background: var(--color-bg-lighter);
  border: 1px solid var(--color-border);
  cursor: pointer;
  transition: var(--transition);
}

.photo-card img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: var(--transition);
}

.photo-card:hover {
  transform: scale(1.02);
  border-color: var(--color-accent);
  box-shadow: none;
}

.photo-card:hover img {
  filter: brightness(0.8);
}

.photo-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(15, 15, 15, 0.9);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  opacity: 0;
  transition: opacity 0.3s ease;
  padding: var(--spacing-lg);
  text-align: center;
}

.photo-card:hover .photo-overlay {
  opacity: 1;
}

.photo-overlay h3 {
  color: var(--color-accent);
  margin: 0 0 var(--spacing-sm);
  font-size: 1.1rem;
}

.photo-overlay .photo-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-xs);
  justify-content: center;
}

.photo-overlay .photo-tag {
  display: inline-block;
  padding: var(--spacing-xs) var(--spacing-sm);
  background-color: rgba(156, 163, 175, 0.18);
  color: var(--color-accent);
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
}

.photo-card .photo-meta {
  position: absolute;
  bottom: var(--spacing-sm);
  left: var(--spacing-sm);
  right: var(--spacing-sm);
  background: rgba(15, 15, 15, 0.95);
  padding: var(--spacing-sm);
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.photo-card:hover .photo-meta {
  opacity: 1;
}

.albums-empty {
  text-align: center;
  padding: var(--spacing-xl);
  color: var(--color-text-secondary);
  grid-column: 1 / -1;
}

/* ===============================
   Responsive Design
   =============================== */
@media (max-width: 768px) {
  :root {
    --font-size-xl: 1.5rem;
    --font-size-lg: 1.2rem;
  }

  header {
    padding: var(--spacing-sm);
  }

  nav {
    gap: var(--spacing-sm);
    flex-wrap: nowrap;
    gap: 0;
  }

  .nav-links {
    display: none !important;
    margin-left: 0;
  }

  .nav-links.open {
    display: flex !important;
  }

  #menu-toggle {
    display: block !important;
  }

  main {
    padding: var(--spacing-md) var(--spacing-xs);
  }

  .content-wrapper {
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
    align-items: start;
  }

  .hero {
    flex-direction: column;
    text-align: center;
    gap: var(--spacing-md);
  }

  .hero-text h1,
  .hero-text h2,
  .hero-text p {
    text-align: center;
  }

  .hero-buttons {
    justify-content: center;
  }

  .hero-image img {
    max-width: 90%;
  }

  .home-about {
    grid-column: 1;
  }

  .research-grid {
    display: none;
  }

  .pub-list,
  .blog-banners,
  .albums-grid {
    grid-template-columns: 1fr !important;
    gap: var(--spacing-sm);
  }

  footer .footer-content {
    gap: var(--spacing-xs);
    padding: var(--spacing-md) var(--spacing-sm);
  }
}

@media (max-width: 480px) {
  :root {
    --font-size-xl: 1.3rem;
    --font-size-lg: 1rem;
    --spacing-md: 1rem;
  }

  header {
    padding: var(--spacing-xs) var(--spacing-sm);
  }

  nav {
    gap: var(--spacing-xs);
    flex-wrap: nowrap;
  }

  .nav-links {
    display: none !important;
    margin-left: 0;
  }

  .nav-links.open {
    display: flex !important;
  }

  #menu-toggle {
    display: block !important;
  }

  .nav-links.open a {
    padding: var(--spacing-sm) 0;
  }

  nav a {
    font-size: 0.95rem;
  }

  .hero-text h1 {
    font-size: 1.4rem;
  }

  .hero-text h2 {
    font-size: 1rem;
  }

  .hero-buttons .btn {
    padding: var(--spacing-xs) 0.8rem;
    font-size: 0.9rem;
  }

  .social-links {
    gap: var(--spacing-xs);
  }

  .social-links svg {
    width: 18px;
    height: 18px;
  }
}