:root {
  --gold:#f8c471;
  --teal:#4fd1c5;
  --text:#ffffff;
  --glass-bg: rgba(0,0,0,0.40);
  --card-bg: rgba(255,255,255,0.06);
  --card-stroke: rgba(255,255,255,0.18);
}

/* === Base === */
html { scroll-behavior:smooth; }
body {
  font-family:"Segoe UI", Arial, sans-serif;
  margin:0; padding:0;
  color:var(--text);
  background:#000;
  overflow-x:hidden;
}

/* === Background video === */
.video-container {
  position:fixed; inset:0; z-index:-2; overflow:hidden;
}
.video-container video {
  width:100%; height:100%; object-fit:cover;
  filter: brightness(0.98) contrast(1.06) saturate(1.08);
}
.video-container::before {
  content:"";
  position:absolute; inset:0; z-index:1;
  background:
    radial-gradient(55% 50% at 50% 35%, rgba(255,255,255,0.10), transparent 62%),
    linear-gradient(135deg, rgba(0,0,0,0.34), rgba(0,0,0,0.22));
}

/* === Scroll progress bar === */
.scroll-progress {
  position:fixed; top:0; left:0; height:3px; width:0%;
  background:linear-gradient(90deg, var(--gold), var(--teal));
  border-radius:0 2px 2px 0;
  box-shadow:0 0 12px rgba(79,209,197,0.55);
  z-index:2000; pointer-events:none;
  transition:width 0.08s linear;
  mix-blend-mode:screen;
}

/* === Navbar === */
.navbar {
  position:fixed; top:0; left:0; right:0;
  background: rgba(0,0,0,0.38);
  backdrop-filter: blur(10px);
  padding:14px 18px;
  display:flex; justify-content:center; align-items:center; gap:36px;
  z-index:1200;
  box-shadow:0 2px 20px rgba(0,0,0,0.6);
}
.navbar a, .navbar .dropbtn {
  color:#fff; font-size:18px; text-decoration:none;
  display:inline-flex; align-items:center; gap:8px;
  position:relative; transition:all .25s ease;
}
.navbar a:hover, .navbar .dropbtn:hover {
  background:linear-gradient(90deg, var(--gold), var(--teal));
  -webkit-background-clip:text;
  -webkit-text-fill-color:transparent;
}
.navbar a::after, .navbar .dropbtn::after {
  content:""; position:absolute; left:0; bottom:-6px; height:2px; width:0;
  background:linear-gradient(90deg, var(--gold), var(--teal));
  transition:width .25s ease;
}
.navbar a:hover::after, .navbar .dropbtn:hover::after { width:100%; }

/* Dropdown */
.dropdown { position:relative; }
.dropdown-content {
  display:none; position:absolute; top:120%; left:0;
  min-width:170px; padding:8px;
  background: rgba(0,0,0,0.92);
  border:1px solid var(--card-stroke);
  border-radius:10px;
  box-shadow:0 10px 28px rgba(0,0,0,0.45);
  backdrop-filter: blur(8px);
  animation:fadeIn .2s ease;
  z-index: 1400;
}
.dropdown-content a {
  display:block; padding:10px 12px; border-radius:8px;
  color:#fff; text-decoration:none; transition:.2s ease;
}
.dropdown-content a:hover {
  background: linear-gradient(90deg, rgba(248,196,113,0.15), rgba(79,209,197,0.15));
  box-shadow: inset 0 0 0 1px rgba(255,255,255,0.05);
}
.dropdown:hover .dropdown-content { display:block; }

/* === Main container === */
.container {
  max-width:1000px;
  margin:130px auto 60px;
  padding:36px 26px;
  background:var(--glass-bg);
  border-radius:16px;
  border:1px solid var(--card-stroke);
  box-shadow: 0 0 24px rgba(79,209,197,0.30);
  backdrop-filter: blur(10px);
  animation:fadeIn .7s ease both;
}

/* Headings */
h1, h2 {
  background:linear-gradient(90deg, var(--gold), var(--teal));
  -webkit-background-clip:text;
  -webkit-text-fill-color:transparent;
  text-align:center;
  margin: 0 0 18px;
}
h1 { font-size:32px; }
h2 { font-size:24px; margin-top:40px; }

/* === Publication Cards === */
.publication-card {
  background:var(--card-bg);
  border:1px solid var(--card-stroke);
  border-radius:14px;
  padding:20px 22px;
  margin:22px auto;
  max-width:860px;
  transition:transform .25s ease, box-shadow .25s ease, background .25s ease;
  opacity:0; transform: translateY(18px);
}
.publication-card.visible {
  opacity:1; transform: translateY(0);
  transition: opacity .6s ease, transform .6s ease;
}
.publication-card:hover {
  transform: translateY(-4px);
  box-shadow:0 10px 26px rgba(0,0,0,0.35), 0 0 22px rgba(248,196,113,0.25);
  background:rgba(0,0,0,0.55);
}
.publication-title {
  font-size:20px; font-weight:700;
  color:var(--gold); margin-bottom:8px;
  text-align:justify;
}
.publication-authors {
  font-size:18px; margin-bottom:6px; text-align:justify;
}
.publication-journal {
  font-style:italic; color:#ddd; margin-bottom:10px; text-align:justify;
}
.publication-actions {
  text-align:right; margin-top:8px; display:flex; gap:8px;
  justify-content:flex-end; flex-wrap:wrap;
}
.btn {
  display:inline-block; padding:8px 12px; border-radius:8px;
  font-weight:600; font-size:14px; text-decoration:none; color:#0b0b0b;
  background:linear-gradient(135deg, var(--gold), var(--teal));
  border:1px solid rgba(255,255,255,0.25);
  box-shadow:0 6px 18px rgba(0,0,0,0.35);
  transition: transform .2s ease, box-shadow .2s ease, filter .2s ease;
}
.btn:hover {
  transform: translateY(-1px);
  filter: brightness(1.02);
  box-shadow:0 10px 22px rgba(0,0,0,0.45);
}
.separator {
  height:2px; width:74%; margin:24px auto;
  background:linear-gradient(90deg, transparent, var(--gold), var(--teal), transparent);
  opacity:.55; border-radius:4px;
}

/* === Timeline === */
.timeline {
  position:relative;
  max-width:860px;
  margin:34px auto 10px;
  list-style:none;
  padding:0;
}
.timeline::before {
  content:""; position:absolute; left:50%; top:0; bottom:0; width:3px;
  transform:translateX(-50%);
  background:linear-gradient(180deg, var(--gold), var(--teal));
  opacity:.85; border-radius:2px;
}
.timeline-item {
  position:relative; width:50%; padding:18px 26px;
  box-sizing:border-box;
  opacity:0; transform: translateY(18px);
}
.timeline-item.visible {
  opacity:1; transform: translateY(0);
  transition: opacity .6s ease, transform .6s ease;
}
.timeline-item.left { left:0; text-align:right; }
.timeline-item.right { left:50%; }
.timeline-item::before {
  content:""; position:absolute; top:22px; width:16px; height:16px; border-radius:50%;
  background: radial-gradient(circle at 35% 35%, #fff, var(--gold) 45%, var(--teal));
  border:1px solid rgba(255,255,255,0.7);
  box-shadow:0 0 10px rgba(79,209,197,0.6);
  z-index:1;
}
.timeline-item.left::before { right:-9px; }
.timeline-item.right::before { left:-9px; }
.timeline-item .content {
  background:var(--card-bg);
  padding:14px; border-radius:12px;
  border:1px solid var(--card-stroke);
  transition: background .25s ease, transform .25s ease, box-shadow .25s ease;
}
.timeline-item .content:hover {
  background:rgba(0,0,0,0.55);
  transform: translateY(-3px);
  box-shadow:0 10px 20px rgba(0,0,0,0.35), 0 0 14px rgba(248,196,113,0.25);
}
.timeline-item h3 {
  margin:0 0 8px;
  background:linear-gradient(90deg, var(--gold), var(--teal));
  -webkit-background-clip:text;
  -webkit-text-fill-color:transparent;
}

/* Mobile timeline */
@media (max-width: 768px) {
  .timeline::before { left:10px; transform:none; }
  .timeline-item { width:100%; left:0; text-align:left; padding-left:36px; }
  .timeline-item::before { left:2px; right:auto; }
}

/* === Footer === */
.footer {
  text-align:center;
  padding:22px;
  background: rgba(0,0,0,0.55);
  border-top:1px solid var(--card-stroke);
  box-shadow:0 -2px 18px rgba(0,0,0,0.35);
  color:#fff;
}
.footer a {
  color:var(--gold);
  text-decoration:none;
}
.footer a:hover {
  color:#fff;
  text-shadow:0 0 10px var(--gold), 0 0 16px var(--teal);
}

/* === Back to top === */
#backToTop {
  position:fixed; right:24px; bottom:26px;
  width:48px; height:48px;
  border:none; border-radius:50%;
  background:linear-gradient(135deg, var(--gold), var(--teal));
  color:#0b0b0b; font-size:20px; cursor:pointer;
  box-shadow:0 8px 22px rgba(0,0,0,0.35), 0 0 18px rgba(79,209,197,0.45);
  display:grid; place-items:center;
  opacity:0; visibility:hidden; transform: translateY(8px);
  transition: all .25s ease;
  z-index:1300;
}
#backToTop.show {
  opacity:1; visibility:visible; transform: translateY(0);
}
#backToTop:hover {
  transform: translateY(-2px) scale(1.04);
}

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

/* === Responsive tweaks === */
@media (max-width: 940px) {
  .container { margin:120px 14px 50px; padding:24px 16px; }
}