@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Outfit:wght@400;500;600;700&display=swap');

:root {
  --bg-color: #0b0f19;
  --bg-color-alt: #111827;
  --text-main: #f3f4f6;
  --text-muted: #9ca3af;
  --accent: #3b82f6;
  --accent-glow: rgba(59, 130, 246, 0.4);
  --border-color: rgba(255, 255, 255, 0.1);
  --card-bg: rgba(17, 24, 39, 0.7);
  --glass-bg: rgba(11, 15, 25, 0.6);
  --glass-border: rgba(255, 255, 255, 0.05);

  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-display: 'Outfit', system-ui, sans-serif;
  
  --max-width: 900px;
  --nav-height: 70px;
}

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-color);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
}

/* Background blob effects */
.bg-blobs {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
}

.blob {
  position: absolute;
  filter: blur(80px);
  opacity: 0.5;
  border-radius: 50%;
  animation: float 20s infinite ease-in-out alternate;
}

.blob-1 {
  top: -10%;
  left: -10%;
  width: 50vw;
  height: 50vw;
  background: radial-gradient(circle, rgba(59,130,246,0.15) 0%, rgba(0,0,0,0) 70%);
}

.blob-2 {
  bottom: -20%;
  right: -10%;
  width: 60vw;
  height: 60vw;
  background: radial-gradient(circle, rgba(139,92,246,0.1) 0%, rgba(0,0,0,0) 70%);
  animation-delay: -5s;
}

@keyframes float {
  0% { transform: translate(0, 0) scale(1); }
  100% { transform: translate(5%, 5%) scale(1.1); }
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.2;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

h1 {
  font-size: 3rem;
  background: linear-gradient(135deg, #fff 0%, #9ca3af 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 0.5rem;
}

h2 {
  font-size: 2rem;
  margin-top: 3rem;
  margin-bottom: 1.5rem;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 0.5rem;
  color: #f9fafb;
}

h3 {
  font-size: 1.25rem;
  margin-top: 2rem;
  color: #e5e7eb;
}

p {
  margin-bottom: 1.25rem;
  color: var(--text-muted);
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: all 0.2s ease;
  position: relative;
}

a:hover {
  text-shadow: 0 0 8px var(--accent-glow);
  color: #60a5fa;
}

p a {
  border-bottom: 1px solid transparent;
}
p a:hover {
  border-bottom: 1px solid var(--accent);
}

ul, ol {
  margin-left: 1.5rem;
  margin-bottom: 1.5rem;
  color: var(--text-muted);
}

li {
  margin-bottom: 0.5rem;
}

/* Layout */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 2rem;
}

header {
  position: fixed;
  top: 0;
  width: 100%;
  height: var(--nav-height);
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--glass-border);
  z-index: 100;
  display: flex;
  align-items: center;
  transition: all 0.3s ease;
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
}

.logo {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.25rem;
  color: #fff;
  letter-spacing: -0.02em;
}

.logo span {
  color: var(--accent);
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
  margin: 0;
}

.nav-links a {
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 500;
  padding: 0.5rem 0;
}

.nav-links a:hover, .nav-links a.active {
  color: #fff;
}

.nav-links a.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--accent);
  border-radius: 2px;
  box-shadow: 0 0 8px var(--accent-glow);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: #fff;
  font-size: 1.5rem;
  cursor: pointer;
}

main {
  flex: 1;
  padding-top: calc(var(--nav-height) + 4rem);
  padding-bottom: 4rem;
  min-height: calc(100vh - 80px);
}

.fade-in {
  opacity: 0;
  transform: translateY(20px);
  animation: fadeIn 0.8s forwards cubic-bezier(0.16, 1, 0.3, 1);
}

.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }
.delay-3 { animation-delay: 0.3s; }

@keyframes fadeIn {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Hero Section */
.hero {
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  margin-top: 2rem;
  min-height: 40vh;
  margin-bottom: 2rem;
}

.hero p {
  font-size: 1.15rem;
  max-width: 700px;
}

/* Cards & Lists */
.card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 1.5rem;
  margin-bottom: 1.5rem;
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
  backdrop-filter: blur(10px);
}

.card:hover {
  transform: translateY(-2px);
  border-color: rgba(255, 255, 255, 0.2);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.paper-list li, .talk-list li {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1rem 1.25rem;
  margin-bottom: 1rem;
  list-style: none;
  transition: all 0.2s ease;
}

.paper-list li:hover, .talk-list li:hover {
  background: var(--bg-color-alt);
  border-color: rgba(255, 255, 255, 0.15);
}

.paper-title {
  font-weight: 500;
  color: #fff;
  display: block;
  margin-bottom: 0.25rem;
}

.paper-authors {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.paper-journal {
  font-size: 0.9rem;
  font-style: italic;
  color: #d1d5db;
}

.paper-links {
  margin-top: 0.5rem;
  display: flex;
  gap: 1rem;
  font-size: 0.85rem;
}

.tag {
  display: inline-block;
  padding: 0.2rem 0.6rem;
  border-radius: 4px;
  background: rgba(59, 130, 246, 0.1);
  color: var(--accent);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.profile-img {
  width: 150px;
  height: 150px;
  border-radius: 50%;
  object-fit: cover;
  border: 2px solid var(--border-color);
  margin-bottom: 1.5rem;
  box-shadow: 0 0 20px rgba(0,0,0,0.5);
}

footer {
  text-align: center;
  padding: 2rem 0;
  border-top: 1px solid var(--border-color);
  color: var(--text-muted);
  font-size: 0.85rem;
  margin-top: auto;
}

/* Responsive */
@media (max-width: 768px) {
  h1 { font-size: 2.25rem; }
  h2 { font-size: 1.75rem; }
  
  .mobile-menu-btn {
    display: block;
  }
  
  .nav-links {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    width: 100%;
    background: var(--card-bg);
    backdrop-filter: blur(15px);
    flex-direction: column;
    padding: 2rem;
    gap: 1.5rem;
    align-items: center;
    transform: translateY(-150%);
    transition: transform 0.3s ease;
    border-bottom: 1px solid var(--border-color);
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
  }
  
  .nav-links.show {
    transform: translateY(0);
  }
}