@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;600;800&family=Outfit:wght@400;700&display=swap');

:root {
  --bg-color: #0b1121; /* Royal Dark */
  --bg-secondary: #111a30;
  --primary: #1d4ed8; /* Royal Blue */
  --secondary: #0ea5e9; /* Sky Blue */
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --glass-bg: rgba(17, 26, 48, 0.7);
  --glass-border: rgba(255, 255, 255, 0.1);
}

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

body {
  font-family: 'Inter', sans-serif;
  background-color: var(--bg-color);
  color: var(--text-main);
  line-height: 1.6;
  background-image: radial-gradient(circle at top right, rgba(29, 78, 216, 0.15) 0%, transparent 40%),
                    radial-gradient(circle at bottom left, rgba(14, 165, 233, 0.1) 0%, transparent 40%);
  background-attachment: fixed;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

h1, h2, h3, h4, h5, h6 {
  font-family: 'Outfit', sans-serif;
  color: var(--text-main);
  margin-bottom: 1rem;
}

a {
  text-decoration: none;
  color: var(--secondary);
  transition: all 0.3s ease;
}

a:hover {
  filter: brightness(1.2);
}

.glass-panel {
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  padding: 2.5rem;
  box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.4);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.glass-panel:hover {
  transform: translateY(-5px);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  width: 100%;
}

header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(11, 17, 33, 0.8);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--glass-border);
  padding: 1.2rem 0;
}

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

.nav-logo {
  font-family: 'Outfit', sans-serif;
  font-size: 1.6rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

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

.nav-links a {
  color: var(--text-muted);
  font-weight: 600;
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  position: relative;
  padding-bottom: 5px;
}

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

.nav-links a:hover {
  color: var(--text-main);
}

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

.nav-links a.active {
  color: var(--text-main);
}

main {
  flex: 1;
  padding: 4rem 0;
  animation: fadeIn 0.8s ease-out;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

.section-title {
  text-align: center;
  font-size: 2.5rem;
  margin-bottom: 3rem;
  background: linear-gradient(135deg, #fff, var(--text-muted));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.profile-grid {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 4rem;
  align-items: center;
}

.profile-info h1 {
  font-size: 3.5rem;
  line-height: 1.1;
  margin-bottom: 0.5rem;
}

.profile-info .subtitle {
  font-size: 1.1rem;
  color: var(--secondary);
  font-weight: 500;
  margin-bottom: 2rem;
}

.profile-info p {
  font-size: 1.1rem;
  color: var(--text-muted);
  margin-bottom: 2rem;
  text-align: justify;
}

.contact-links {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 2rem;
}

.contact-item {
  display: flex;
  align-items: center;
  gap: 1rem;
  color: var(--text-muted);
  font-size: 1rem;
}

.contact-item i {
  color: var(--secondary);
  font-size: 1.4rem;
  width: 24px;
  text-align: center;
}

.timeline {
  position: relative;
  max-width: 900px;
  margin: 0 auto;
}

.timeline::after {
  content: '';
  position: absolute;
  width: 2px;
  background: linear-gradient(to bottom, var(--primary), var(--secondary));
  top: 0;
  bottom: 0;
  left: 20px;
  margin-left: -1px;
}

.timeline-item {
  padding: 0 0 2rem 50px;
  position: relative;
}

.timeline-item::after {
  content: '';
  position: absolute;
  width: 20px;
  height: 20px;
  left: 11px;
  background-color: var(--bg-color);
  border: 4px solid var(--secondary);
  top: 0;
  border-radius: 50%;
  z-index: 1;
}

.timeline-date {
  display: inline-block;
  padding: 0.3rem 1rem;
  background: rgba(29, 78, 216, 0.2);
  color: var(--text-main);
  border-radius: 20px;
  font-weight: 600;
  margin-bottom: 1rem;
  font-size: 0.9rem;
  border: 1px solid rgba(29, 78, 216, 0.3);
}

.timeline-title {
  font-size: 1.4rem;
  color: var(--text-main);
  margin-bottom: 0.5rem;
}

.timeline-subtitle {
  font-weight: 600;
  color: var(--secondary);
  margin-bottom: 1rem;
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.skill-category h3 {
  color: var(--text-main);
  border-bottom: 2px solid var(--glass-border);
  padding-bottom: 0.8rem;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.skill-category h3 i {
  color: var(--secondary);
}

.skill-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
}

.tag {
  background: rgba(14, 165, 233, 0.1);
  border: 1px solid rgba(14, 165, 233, 0.3);
  color: var(--text-main);
  padding: 0.5rem 1rem;
  border-radius: 20px;
  font-weight: 600;
  font-size: 0.9rem;
  transition: all 0.3s;
}

.tag:hover {
  background: var(--primary);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(29, 78, 216, 0.4);
}

.publication-item {
  margin-bottom: 1.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--glass-border);
}

.publication-title {
  font-weight: 600;
  font-size: 1.1rem;
  color: var(--text-main);
  margin-bottom: 0.5rem;
}

.publication-meta { color: var(--text-muted); font-size: 0.95rem; }
.publication-link { margin-top: 0.5rem; display: inline-block; font-size: 0.9rem; }

footer {
  text-align: center;
  padding: 2rem;
  border-top: 1px solid var(--glass-border);
  color: var(--text-muted);
  font-size: 0.95rem;
  background: rgba(11, 17, 33, 0.5);
}

/* JS Dynamic Elements */
#scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  width: 0%;
  z-index: 10000;
  transition: width 0.1s ease;
}

#back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: var(--primary);
  color: white;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: all 0.4s ease;
  z-index: 999;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.4);
}

#back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

#back-to-top:hover {
  background: var(--secondary);
  transform: translateY(-5px);
}

.reveal-hidden {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.8s ease-out;
}

.reveal-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 768px) {
  .profile-grid { grid-template-columns: 1fr; }
  .nav-links { display: flex; flex-wrap: wrap; justify-content: center; gap: 1rem; }
  .contact-links { grid-template-columns: 1fr; }
  .profile-info h1 { font-size: 2.5rem; }
}