:root {
  /* Color Palette */
  --color-primary: #ab0520; /* Cardinal Red */
  --color-primary-light: #d6082a;
  --color-primary-dark: #7a0316;
  --color-accent: #0c234b; /* Navy Blue */
  --color-accent-hover: #1a3c78;

  --color-bg-main: #f8fafc; /* Very light slate for main background */
  --color-bg-surface: #ffffff; /* White for cards/containers */
  --color-bg-alt: #f1f5f9;

  --color-text-main: #334155; /* Slate gray for readable text */
  --color-text-muted: #64748b;
  --color-text-heading: #0f172a; /* Darkest slate for headings */

  --color-border: #e2e8f0;

  /* Typography */
  --font-sans:
    "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica,
    Arial, sans-serif;
  --font-serif:
    "Merriweather", Georgia, serif; /* Occasional use for academic feel */

  /* Layout & Spacing */
  --max-width: 1200px;
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 4rem;
  --spacing-xl: 6rem;

  /* Effects */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md:
    0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg:
    0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-hover:
    0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);

  --radius-md: 0;
  --radius-lg: 0;
  --radius-full: 0;

  --transition-fast: 0.15s ease-in-out;
  --transition-normal: 0.3s ease-in-out;
  --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  font-family: var(--font-sans);
  color: var(--color-text-main);
  background-color: var(--color-bg-main);
  line-height: 1.6;
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Typography */
h1,
h2,
h3,
h4,
h5,
h6 {
  color: var(--color-text-heading);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--spacing-sm);
}

h1 {
  font-size: 2.5rem;
  letter-spacing: -0.02em;
}
h2 {
  font-size: 2rem;
  letter-spacing: -0.01em;
}
h3 {
  font-size: 1.5rem;
}
h4 {
  font-size: 1.25rem;
}

p {
  margin-bottom: var(--spacing-sm);
  font-size: 1.125rem;
}

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

a:hover {
  color: var(--color-primary-light);
}

/* Layout Utilities */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-sm);
}

.section {
  padding: var(--spacing-lg) 0;
}

.section-alt {
  background-color: var(--color-bg-surface);
}

.grid {
  display: grid;
  gap: var(--spacing-md);
}

.flex {
  display: flex;
}

.items-center {
  align-items: center;
}

.justify-between {
  justify-content: space-between;
}

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

/* Navigation */
.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  padding: 1rem 0;
  transition: all var(--transition-normal);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo {
  font-weight: 800;
  font-size: 1.5rem;
  color: var(--color-primary);
  letter-spacing: -0.5px;
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav-link {
  color: var(--color-text-main);
  font-weight: 500;
  font-size: 1rem;
  position: relative;
  padding-bottom: 0.25rem;
}

.nav-link::after {
  content: "";
  position: absolute;
  width: 0;
  height: 2px;
  bottom: 0;
  left: 0;
  background-color: var(--color-accent);
  transition: width var(--transition-normal);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-link:hover,
.nav-link.active {
  color: var(--color-primary);
}

/* Hero Section */
.hero {
  position: relative;
  min-height: 80vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  background-color: #000000; /* Fallback */
}

.hero-bg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 0;
  opacity: 0.3; /* Darken background for text readability */
}

.hero-content {
  position: relative;
  z-index: 1;
  color: white;
  max-width: 800px;
}

.hero h1 {
  color: white;
  font-size: 3.5rem;
  margin-bottom: 1rem;
  animation: fadeUp 1s ease-out;
}

.hero .subtitle {
  font-size: 1.5rem;
  font-weight: 300;
  color: #e2e8f0;
  margin-bottom: 2rem;
  animation: fadeUp 1s ease-out 0.2s both;
}

.hero .bio-snippet {
  font-size: 1.125rem;
  color: #cbd5e1;
  max-width: 600px;
  animation: fadeUp 1s ease-out 0.4s both;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  border-radius: 0;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
  border: none;
  font-size: 1rem;
  text-align: center;
}

.btn-primary {
  background-color: var(--color-accent);
  color: white;
}

.btn-primary:hover {
  background-color: var(--color-accent-hover);
  color: white;
}

.btn-outline {
  background-color: transparent;
  color: white;
  border: 2px solid white;
}

.btn-outline:hover {
  background-color: rgba(255, 255, 255, 0.1);
  color: white;
}

.btn-outline-dark {
  background-color: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}

.btn-outline-dark:hover {
  background-color: var(--color-primary);
  color: white;
}

/* Cards */
.card {
  background-color: var(--color-bg-surface);
  border-radius: 0;
  padding: var(--spacing-md);
  box-shadow: none;
  border: 1px solid var(--color-border);
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  height: 100%;
}

.card:hover {
  border-color: var(--color-primary);
}

.card-tag {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  border-radius: 0;
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 1rem;
  background-color: var(--color-bg-alt);
  color: var(--color-primary);
}

.card-title {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
}

.card-meta {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  margin-bottom: 1rem;
  flex-grow: 1;
}

/* Two Column Layouts */
.split-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-lg);
  align-items: center;
}

.profile-img-container {
  border-radius: 0;
  overflow: hidden;
  box-shadow: none;
  position: relative;
}

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

/* Footer */
.footer {
  background-color: var(--color-text-heading);
  color: white;
  padding: var(--spacing-md) 0;
  margin-top: auto;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.social-links {
  display: flex;
  gap: 1.5rem;
}

.social-links a {
  color: #cbd5e1;
  font-size: 1.5rem;
  display: inline-block;
  transition: color var(--transition-fast);
}

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

/* Animations */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-on-scroll {
  opacity: 0;
  transform: translateY(20px);
  transition:
    opacity 0.6s ease-out,
    transform 0.6s ease-out;
}

.animate-on-scroll.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* Badges/Tags for affiliations */
.badge-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1rem;
}

.badge {
  background-color: rgba(59, 130, 246, 0.1);
  color: var(--color-primary-dark);
  padding: 0.25rem 0.75rem;
  border-radius: 0;
  font-size: 0.875rem;
  font-weight: 500;
  border: 1px solid rgba(59, 130, 246, 0.2);
}

/* Media Queries */
@media (max-width: 768px) {
  h1 {
    font-size: 2rem;
  }
  h2 {
    font-size: 1.5rem;
  }

  .hero h1 {
    font-size: 2.5rem;
  }
  .hero .subtitle {
    font-size: 1.25rem;
  }

  .split-section {
    grid-template-columns: 1fr;
  }

  .nav-links {
    display: none; /* Add mobile menu logic here, typically a hamburger */
  }

  .section {
    padding: var(--spacing-md) 0;
  }
}

/* Publication Cards Specifics */
.pub-card {
  position: relative;
  border-radius: 0;
  padding: 2rem;
  box-shadow: var(--shadow-md);
  transition:
    transform var(--transition-normal),
    box-shadow var(--transition-normal);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  overflow: hidden;
  background-color: var(--color-bg-surface);
}

.pub-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.pub-card.has-bg-image {
  color: #f8fafc; /* text-slate-50 */
  border: none;
}

.pub-card.has-bg-image .pub-title {
  color: #ffffff;
}

.pub-card.has-bg-image .pub-authors {
  color: #cbd5e1; /* text-slate-300 */
}

.pub-card.has-bg-image .pub-journal {
  color: #e2e8f0; /* text-slate-200 */
}

.pub-card.has-bg-image .pub-links a {
  color: #93c5fd; /* text-blue-300 */
}

.pub-card.has-bg-image .pub-links a:hover {
  color: #bfdbfe; /* text-blue-200 */
}

/* Update badge style to have hover effects */
.badge {
  transition:
    background-color var(--transition-fast),
    color var(--transition-fast);
}

.badge:hover {
  background-color: var(--color-primary-light);
  color: white;
}

a.badge-link {
  text-decoration: none;
  display: inline-block;
}

a.badge-link:hover {
  background-color: var(--color-primary);
  color: white;
}