/* ════════════════════ iPAD / TABLET (768px – 1024px) ════════════════════ */
@media (min-width: 769px) and (max-width: 1024px) {
  .nav-links { display: none; }
  .hamburger { display: flex; }

  .hero-content { padding-top: calc(var(--nav-h) + 10px); }
  #home h1 { font-size: clamp(2rem, 5vw, 3rem); }

  .news-grid { grid-template-columns: repeat(2, 1fr); }
  .research-grid { grid-template-columns: repeat(2, 1fr); }
  .people-grid { grid-template-columns: repeat(3, 1fr); }
  .gallery-grid { columns: 3; }
  .contact-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .edu-item { padding: 22px 24px; }
  .skills-tags { gap: 10px; }
  .pub-controls { flex-wrap: wrap; gap: 12px; }
  .filter-pills { flex-wrap: wrap; }
  .container { padding: 0 28px; }
  .section-padding { padding: 80px 0; }

  /* Timeline stays 2-col on iPad */
  .timeline-item { gap: 0; }
}

/* ═══════════════════════════════════════
   MOHAMMAD ABU JASEM — RESEARCHER WEBSITE
   Spintronics | Khulna University
═══════════════════════════════════════ */

@import url('https://fonts.googleapis.com/css2?family=Syne:wght@400;500;600;700;800&family=DM+Sans:wght@300;400;500;600&family=JetBrains+Mono:wght@400;500&display=swap');

/* ── CSS Variables (Light Mode Default) ── */
:root {
  --primary:     #f6f8fc;
  --primary2:    #edf1f8;
  --accent:      #4f46e5;
  --accent2:     #7c3aed;
  --accent3:     #e11d48;
  --text:        #374151;
  --text-bright: #111827;
  --text-muted:  #00000093;
  --card-bg:     rgba(255,255,255,0.92);
  --glass:       rgba(79,70,229,0.04);
  --glass-border:rgba(79,70,229,0.18);
  --nav-bg:      rgba(246,248,252,0.96);
  --nav-h:       70px;
  --radius:      12px;
  --transition:  0.3s cubic-bezier(0.4,0,0.2,1);
  --shadow:      0 4px 24px rgba(79,70,229,0.09);
}

/* ── Dark Mode ── */
body.dark-mode {
  --primary:     #07091c;
  --primary2:    #0b0f28;
  --accent:      #818cf8;
  --accent2:     #a78bfa;
  --accent3:     #f87171;
  --text:        #c4d0e3;
  --text-bright: #ffffff;
  --text-muted:  #64748b;
  --card-bg:     rgba(12,16,42,0.75);
  --glass:       rgba(129,140,248,0.04);
  --glass-border:rgba(129,140,248,0.14);
  --nav-bg:      rgba(7,9,28,0.92);
  --shadow:      0 4px 24px rgba(0,0,0,0.35);
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: 'DM Sans', sans-serif;
  background: var(--primary);
  color: var(--text);
  line-height: 1.7;
  overflow-x: hidden;
  transition: background 0.3s, color 0.3s;
}
h1,h2,h3,h4,h5 { font-family: 'Syne', sans-serif; color: var(--text-bright); line-height: 1.2; }
a { color: var(--accent); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--accent2); }
img { max-width: 100%; height: auto; display: block; }
button { cursor: pointer; font-family: 'DM Sans', sans-serif; font-weight: 600; border: none; outline: none; transition: var(--transition); }

/* ── Scrollbar ── */
::-webkit-scrollbar { width: 0px; }
::-webkit-scrollbar-track { background: var(--primary2); }
::-webkit-scrollbar-thumb { background: var(--accent); border-radius: 3px; }

/* ── Utility ── */
.container { max-width: 1180px; margin: 0 auto; padding: 0 24px; }
.section-padding { padding: 96px 0; }
.section-alt { background: var(--primary2); }
.text-accent { color: var(--accent); }
.text-accent2 { color: var(--accent2); }

/* ── Section Heading ── */
.section-heading { text-align: center; margin-bottom: 60px; }
.section-heading h2 { font-size: clamp(1.8rem, 4vw, 2.5rem); font-weight: 700; margin-bottom: 12px; }
.section-heading p { font-size: 1.05rem; color: var(--text-muted); max-width: 580px; margin: 0 auto; }
.heading-line { width: 44px; height: 2px; background: linear-gradient(90deg, var(--accent), var(--accent2)); margin: 14px auto; border-radius: 2px; }

/* ── Glass Card ── */
.glass-card {
  background: var(--card-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  box-shadow: var(--shadow);
  transition: var(--transition);
}
.glass-card:hover { border-color: var(--accent); box-shadow: 0 8px 32px rgba(79,70,229,0.15); transform: translateY(-4px); }

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 26px;
  border-radius: 50px;
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.5px;
  transition: var(--transition);
}
.btn-primary { background: transparent; color: var(--accent); border: 1.5px solid var(--accent); }
.btn-primary:hover { background: var(--accent); color: white;  }
.btn-outline { background: transparent; color: var(--accent); border: 1.5px solid var(--accent); }
.btn-outline:hover { background: var(--accent); color: white; }

/* ════════════════════ NAVBAR ════════════════════ */
#navbar {
  position: fixed; top: 0; width: 100%; z-index: 1000;
  height: var(--nav-h); display: flex; align-items: center;
  transition: background 0.4s, box-shadow 0.4s;
}
#navbar.scrolled { background: var(--nav-bg); backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px); border-bottom: 1px solid var(--glass-border); box-shadow: var(--shadow); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; width: 100%; max-width: 1180px; margin: 0 auto; padding: 0 24px; }
.nav-logo { display: flex; align-items: center; gap: 10px; text-decoration: none; }
.nav-logo .orbit-icon { width: 36px; height: 36px; }
.nav-logo span { font-family: 'Syne', sans-serif; font-size: 1.05rem; font-weight: 700; color: var(--text-bright); letter-spacing: 0.5px; }
.nav-logo span em { color: var(--accent); font-style: normal; }
.nav-links { display: flex; align-items: center; gap: 2px; list-style: none; }
.nav-links a { padding: 6px 11px; font-size: 0.8rem; font-weight: 600; letter-spacing: 1px; text-transform: uppercase; color: var(--text); border-radius: 6px; transition: var(--transition); }
.nav-links a:hover, .nav-links a.active { color: var(--accent); background: var(--glass); }
.hamburger { display: none; flex-direction: column; gap: 5px; cursor: pointer; padding: 8px; }
.hamburger span { display: block; width: 22px; height: 2px; background: var(--text-bright); border-radius: 2px; transition: var(--transition); }
.hamburger.open span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.hamburger.open span:nth-child(2) { opacity: 0; }
.hamburger.open span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

.mobile-nav { display: none; position: fixed; top: var(--nav-h); left: 0; width: 100%; height: calc(100vh - var(--nav-h)); background: var(--nav-bg); backdrop-filter: blur(20px); z-index: 999; flex-direction: column; align-items: center; justify-content: center; gap: 28px; list-style: none; }
.mobile-nav.open { display: flex; }
.mobile-nav a { font-family: 'Syne', sans-serif; font-size: 1.15rem; letter-spacing: 2.5px; color: var(--text); text-transform: uppercase; }
.mobile-nav a:hover { color: var(--accent); }
.mobile-theme-toggle { font-family: 'Syne', sans-serif; font-size: 0.85rem; letter-spacing: 2px; text-transform: uppercase; padding: 8px 28px; border-radius: 20px; border: 1px solid var(--glass-border); background: transparent; color: var(--text); cursor: pointer; transition: all 0.2s; }
.mobile-theme-toggle:hover { border-color: var(--accent); color: var(--accent); }

.theme-toggle {
  background: none;
  border: 1.5px solid var(--glass-border);
  border-radius: 20px;
  padding: 5px 14px;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-muted);
  letter-spacing: 1px;
  cursor: pointer;
  transition: var(--transition);
}
.theme-toggle:hover { border-color: var(--accent); color: var(--accent); }

/* ════════════════════ HERO ════════════════════ */
/* ════ HERO ════ */
#home {
  position: relative; min-height: 100vh; display: flex; align-items: center;
  justify-content: center; overflow: hidden;
  background: var(--primary);
  transition: background 0.3s;
}
body.dark-mode #home { background: #000000}

#hero-canvas {
  position: absolute; top: 0; left: 0; width: 100%; height: 100%;
  z-index: 0; pointer-events: none;
}

/* Centre-aligned single-column hero */
#home .container { position: relative; z-index: 1; width: 100%; }
.hero-content {
  display: flex; flex-direction: column; align-items: center;
  text-align: center; padding-top: var(--nav-h); padding-bottom: 40px;
  max-width: 760px; margin: 0 auto;
}

/* Badge pill */
.hero-badge-pill {
  display: inline-flex; align-items: center; gap: 8px;
  border: 1px solid var(--glass-border); border-radius: 999px;
  padding: 6px 18px; font-size: 0.82rem; font-family: 'JetBrains Mono', monospace;
  color: var(--text-muted); background: var(--glass);
  margin-bottom: 28px; letter-spacing: 0.5px;
  backdrop-filter: blur(6px);
}
.badge-dot {
  width: 7px; height: 7px; border-radius: 50%; background: #f5a623;
  box-shadow: 0 0 6px #f5a623; animation: pulse-dot 2s ease-in-out infinite;
}
@keyframes pulse-dot { 0%,100% { opacity:1; transform:scale(1); } 50% { opacity:0.5; transform:scale(1.35); } }

/* Heading */
#home h1 {
  font-size: clamp(2.6rem, 6vw, 4.2rem); font-weight: 800; line-height: 1.08;
  margin-bottom: 18px; color: var(--text-bright);
  font-family: 'Syne', sans-serif; letter-spacing: -1px;
}
body.dark-mode #home h1 { color: #ffffff; }

/* Typing tagline */
.hero-tagline {
  font-family: 'JetBrains Mono', monospace; font-size: 1rem;
  color: var(--accent); margin-bottom: 18px; min-height: 28px;
}
.cursor { display: inline-block; width: 2px; height: 1em; background: var(--accent); margin-left: 2px; vertical-align: text-bottom; animation: blink 1s step-end infinite; }
@keyframes blink { 50% { opacity: 0; } }

/* Description */
.hero-desc {
  font-size: 1.05rem; color: var(--text-muted); margin-bottom: 36px;
  max-width: 560px; line-height: 1.7;
}

/* CTA Buttons */
.hero-buttons { display: flex; gap: 14px; flex-wrap: wrap; justify-content: center; margin-bottom: 32px; }
.btn-hero-primary {
  background: transparent; color: var(--text-bright);
  font-weight: 600; padding: 13px 28px; border-radius: 999px;
  font-size: 0.95rem; border: 1.5px solid var(--glass-border);
  transition: var(--transition); backdrop-filter: blur(4px);
  display: inline;
}
.btn-hero-primary:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-2px); }
.btn-hero-outline {
  background: transparent; color: var(--text-bright);
  font-weight: 600; padding: 13px 28px; border-radius: 999px;
  font-size: 0.95rem; border: 1.5px solid var(--glass-border);
  transition: var(--transition); backdrop-filter: blur(4px);
}
.btn-hero-outline:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-2px); }

/* Trust pills */
.hero-trust-pills {
  display: flex; gap: 10px; flex-wrap: wrap; justify-content: center; margin-bottom: 32px;
}
.hero-trust-pills span {
  font-size: 0.78rem; padding: 5px 14px; border-radius: 999px;
  border: 1px solid var(--glass-border); color: var(--text-muted);
  background: var(--glass); font-family: 'JetBrains Mono', monospace;
  letter-spacing: 0.3px;
}

/* Social links */
.hero-socials { display: flex; gap: 10px; align-items: center; }
.hero-socials a {
  width: 38px; height: 38px; border-radius: 50%;
  border: 1.5px solid var(--glass-border);
  display: flex; align-items: center; justify-content: center;
  color: var(--text-muted); transition: var(--transition);
}
.hero-socials a:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-3px); box-shadow: 0 4px 12px rgba(79,70,229,0.15); }

/* Scroll arrow */
.scroll-arrow { position: absolute; bottom: 28px; left: 50%; transform: translateX(-50%); z-index: 1; display: flex; flex-direction: column; align-items: center; gap: 4px; color: var(--text-muted); animation: bounce 2s ease-in-out infinite; }
.scroll-arrow svg { color: var(--accent); }
@keyframes bounce { 0%,100% { transform: translateX(-50%) translateY(0); } 50% { transform: translateX(-50%) translateY(8px); } }

/* ════════════════════ NEWS ════════════════════ */
.news-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.news-card { border-radius: var(--radius); overflow: hidden; cursor: pointer; }
.news-card .card-image { height: 170px; overflow: hidden; }
.news-card .card-image img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.5s ease; }
.news-card:hover .card-image img { transform: scale(1.06); }
.news-card .card-image .img-placeholder { width: 100%; height: 100%; background: linear-gradient(135deg, var(--accent), var(--accent2)); display: flex; align-items: center; justify-content: center; }
.news-card .card-body { padding: 18px; }
.news-card .date-badge { font-family: 'JetBrains Mono', monospace; font-size: 0.72rem; color: var(--accent); letter-spacing: 2px; margin-bottom: 8px; }
.news-card h3 { font-size: 0.97rem; font-weight: 600; margin-bottom: 8px; line-height: 1.4; }
.news-card p { font-size: 0.88rem; color: var(--text-muted); margin-bottom: 14px; line-height: 1.5; }
.news-card .read-more { font-size: 0.78rem; color: var(--accent); letter-spacing: 1px; text-transform: uppercase; font-weight: 600; display: flex; align-items: center; gap: 5px; }

/* ════════════════════ ACTIVITIES / TIMELINE ════════════════════ */
.timeline { position: relative; max-width: 880px; margin: 0 auto; }
.timeline::before { content: ''; position: absolute; left: 50%; top: 0; bottom: 0; width: 2px; background: linear-gradient(to bottom, var(--accent), var(--accent2)); transform: translateX(-50%); }
.timeline-item { display: grid; grid-template-columns: 1fr 60px 1fr; gap: 0; margin-bottom: 44px; align-items: start; }
.timeline-item:nth-child(odd) .timeline-content { grid-column: 1; text-align: right; }
.timeline-item:nth-child(odd) .timeline-dot { grid-column: 2; }
.timeline-item:nth-child(even) .timeline-content { grid-column: 3; }
.timeline-item:nth-child(even) .timeline-dot { grid-column: 2; }
.timeline-dot { display: flex; align-items: flex-start; justify-content: center; padding-top: 18px; position: relative; z-index: 1; }
.timeline-dot .dot-icon { width: 42px; height: 42px; border-radius: 50%; background: var(--primary); border: 2px solid var(--accent); display: flex; align-items: center; justify-content: center; font-size: 1.1rem; box-shadow: 0 0 12px rgba(79,70,229,0.15); }
.timeline-content { padding: 18px; }
.timeline-content .t-date { font-family: 'JetBrains Mono', monospace; font-size: 0.72rem; color: var(--accent); letter-spacing: 2px; margin-bottom: 6px; }
.timeline-content h3 { font-size: 0.97rem; margin-bottom: 5px; }
.timeline-content p { font-size: 0.88rem; color: var(--text-muted); margin-bottom: 8px; }
.timeline-content .location-badge { display: inline-flex; align-items: center; gap: 4px; font-size: 0.75rem; color: var(--accent2); background: rgba(124,58,237,0.08); padding: 3px 10px; border-radius: 20px; border: 1px solid rgba(124,58,237,0.2); }

/* ════════════════════ RESEARCH ════════════════════ */
.research-intro { text-align: center; max-width: 680px; margin: 0 auto 56px; font-size: 1.05rem; color: var(--text-muted); line-height: 1.7; }
.research-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; margin-bottom: 56px; }
.research-card-flip { height: 210px; }
.research-card-flip.glass-card:hover { transform: none; }
.research-card-inner { width: 100%; height: 100%; position: relative; }
.research-card-front, .research-card-back { position: absolute; inset: 0; border-radius: var(--radius); display: flex; flex-direction: column; align-items: center; justify-content: center; padding: 20px; transition: opacity 0.4s ease, transform 0.4s ease; }
.research-card-front { background: var(--card-bg); border: 1px solid var(--glass-border); box-shadow: var(--shadow); text-align: center; gap: 14px; opacity: 1; transform: translateY(0); }
.research-card-front .r-icon { font-size: 2.2rem; }
.research-card-front h3 { font-size: 0.88rem; }
.research-card-back { background: linear-gradient(135deg, rgba(79,70,229,0.08), rgba(124,58,237,0.08)); border: 1px solid var(--accent); text-align: center; gap: 8px; opacity: 0; transform: translateY(10px); }
.research-card-back p { font-size: 0.82rem; color: var(--text); line-height: 1.5; }
.research-card-back .tags { display: flex; flex-wrap: wrap; gap: 4px; justify-content: center; }
.research-card-back .tag { font-size: 0.68rem; background: rgba(79,70,229,0.12); color: var(--accent); padding: 2px 8px; border-radius: 10px; border: 1px solid rgba(79,70,229,0.2); }
.research-card-flip:hover .research-card-front { opacity: 0; transform: translateY(-10px); }
.research-card-flip:hover .research-card-back { opacity: 1; transform: translateY(0); }

.projects-accordion { max-width: 780px; margin: 0 auto; }
.projects-accordion h3 { text-align: center; font-size: 1.2rem; margin-bottom: 22px; color: var(--text-bright); }
.accordion-item { border: 1px solid var(--glass-border); border-radius: var(--radius); margin-bottom: 10px; overflow: hidden; }
.accordion-header { width: 100%; background: var(--card-bg); padding: 15px 22px; display: flex; align-items: center; justify-content: space-between; cursor: pointer; font-family: 'DM Sans', sans-serif; font-size: 0.97rem; font-weight: 600; color: var(--text-bright); text-align: left; border: none; outline: none; }
.accordion-header .acc-icon { color: var(--accent); font-size: 1.1rem; transition: transform 0.3s; flex-shrink: 0; margin-left: 12px; }
.accordion-item.open .accordion-header .acc-icon { transform: rotate(45deg); }
.accordion-body { max-height: 0; overflow: hidden; transition: max-height 0.4s ease; background: rgba(79,70,229,0.03); }
.accordion-item.open .accordion-body { max-height: 400px; }

/* Inner content layout */
.accordion-content { padding: 16px 22px 20px; display: flex; flex-direction: column; gap: 12px; }
.accordion-content p { font-size: 0.93rem; color: var(--text-muted); line-height: 1.6; margin: 0; }

/* Tags */
.acc-tags { display: flex; flex-wrap: wrap; gap: 8px; }
.acc-tags .tag { display: inline-block; padding: 4px 12px; border-radius: 999px; background: rgba(79,70,229,0.1); color: var(--accent); font-size: 0.78rem; font-weight: 600; letter-spacing: 0.02em; }

/* Status */
.acc-status { font-size: 0.82rem; color: var(--text-muted); font-weight: 500; }
.acc-status span { color: var(--accent); font-weight: 700; }

/* ════════════════════ PUBLICATIONS ════════════════════ */
.pub-controls { display: flex; gap: 16px; flex-wrap: wrap; align-items: center; margin-bottom: 32px; }
.pub-search { flex: 1; min-width: 240px; background: var(--card-bg); border: 1px solid var(--glass-border); border-radius: 50px; padding: 10px 20px; color: var(--text-bright); font-family: 'DM Sans', sans-serif; font-size: 1rem; outline: none; transition: var(--transition); }
.pub-search:focus { border-color: var(--accent); box-shadow: 0 0 16px rgba(79,70,229,0.1); }
.pub-search::placeholder { color: var(--text-muted); }
.filter-pills { display: flex; gap: 8px; flex-wrap: wrap; }
.filter-pill { padding: 6px 15px; border-radius: 20px; font-size: 0.78rem; font-weight: 600; letter-spacing: 0.5px; background: var(--card-bg); border: 1px solid var(--glass-border); color: var(--text-muted); cursor: pointer; transition: var(--transition); }
.filter-pill:hover, .filter-pill.active { background: rgba(79,70,229,0.08); border-color: var(--accent); color: var(--accent); }
.pub-list { display: flex; flex-direction: column; gap: 14px; }
.pub-item { padding: 22px; border-radius: var(--radius); transition: var(--transition); }
.pub-item:hover { border-color: var(--accent); box-shadow: 0 8px 32px rgba(79,70,229,0.15); transform: translateY(-4px); }
.pub-number { font-family: 'JetBrains Mono', monospace; font-size: 0.72rem; color: var(--accent); letter-spacing: 2px; margin-bottom: 7px; }
.pub-item h3 { font-family: 'DM Sans', sans-serif; font-size: 1rem; font-weight: 700; color: var(--text-bright); margin-bottom: 5px; line-height: 1.4; }
.pub-authors { font-size: 0.88rem; color: var(--text-muted); margin-bottom: 5px; font-style: italic; }
.pub-authors .highlight { color: var(--accent2); font-weight: 600; font-style: normal; }
.pub-journal { font-size: 0.88rem; color: var(--text); margin-bottom: 10px; }
.pub-meta { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; margin-bottom: 10px; }
.pub-badge { font-size: 0.7rem; padding: 2px 9px; border-radius: 10px; font-weight: 600; text-transform: uppercase; letter-spacing: 0.5px; }
.pub-badge.journal { background: rgba(79,70,229,0.1); color: var(--accent); }
.pub-badge.conference { background: rgba(124,58,237,0.1); color: var(--accent2); }
.pub-badge.book { background: rgba(225,29,72,0.1); color: var(--accent3); }
.pub-badge.preprint { background: rgba(107,114,128,0.1); color: var(--text-muted); }
.citation-badge { font-size: 0.76rem; color: var(--text-muted); display: flex; align-items: center; gap: 4px; }
.pub-links { display: flex; gap: 8px; }
.pub-link { font-size: 0.76rem; padding: 4px 11px; border-radius: 6px; border: 1px solid var(--glass-border); color: var(--text-muted); transition: var(--transition); cursor: pointer; }
.pub-link:hover { border-color: var(--accent); color: var(--accent); }
.abstract-body { display: none; margin-top: 10px; padding-top: 10px; border-top: 1px solid var(--glass-border); font-size: 0.88rem; color: var(--text-muted); line-height: 1.6; }
.abstract-body.open { display: block; }

/* ════════════════════ PEOPLE ════════════════════ */
.people-tabs { display: flex; gap: 8px; flex-wrap: wrap; justify-content: center; margin-bottom: 36px; }
.people-tab { padding: 7px 18px; border-radius: 20px; font-size: 0.83rem; font-weight: 600; background: var(--card-bg); border: 1px solid var(--glass-border); color: var(--text-muted); cursor: pointer; transition: var(--transition); }
.people-tab.active { background: rgba(79,70,229,0.08); border-color: var(--accent); color: var(--accent); }
.people-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.person-card-flip { height: 270px; }
.person-card-flip.glass-card:hover { transform: none; }
.person-card-inner { width: 100%; height: 100%; position: relative; }
.person-card-front, .person-card-back { position: absolute; inset: 0; border-radius: var(--radius); background: var(--card-bg); border: 1px solid var(--glass-border); box-shadow: var(--shadow); display: flex; flex-direction: column; align-items: center; justify-content: center; padding: 20px; text-align: center; transition: opacity 0.4s ease, transform 0.4s ease; }
.person-card-front img, .person-card-front .person-avatar { width: 78px; height: 78px; border-radius: 50%; object-fit: cover; margin-bottom: 12px; border: 2px solid var(--accent); }
.person-card-front .person-avatar { background: linear-gradient(135deg, var(--accent2), var(--accent)); display: flex; align-items: center; justify-content: center; font-family: 'Syne', sans-serif; font-size: 1.4rem; color: white; }
.person-card-front h3 { font-size: 0.93rem; margin-bottom: 3px; }
.person-card-front .person-role { font-size: 0.78rem; color: var(--accent); margin-bottom: 3px; }
.person-card-front .person-institution { font-size: 0.73rem; color: var(--text-muted); }
.person-card-front { opacity: 1; transform: translateY(0); }
.person-card-back { opacity: 0; transform: translateY(10px); border-color: var(--accent); background: linear-gradient(135deg, rgba(79,70,229,0.06), rgba(124,58,237,0.06)); gap: 9px; }
.person-card-flip:hover .person-card-front { opacity: 0; transform: translateY(-10px); }
.person-card-flip:hover .person-card-back { opacity: 1; transform: translateY(0); }
.person-card-back p { font-size: 0.8rem; color: var(--text-muted); line-height: 1.5; }
.person-socials { display: flex; gap: 8px; margin-top: 8px; }
.person-socials a { width: 30px; height: 30px; border-radius: 50%; border: 1px solid var(--glass-border); display: flex; align-items: center; justify-content: center; color: var(--text-muted); font-size: 0.82rem; transition: var(--transition); }
.person-socials a:hover { border-color: var(--accent); color: var(--accent); }

/* ════════════════════ GALLERY ════════════════════ */
.gallery-filters { display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; margin-bottom: 32px; }
.gallery-grid { columns: 3; column-gap: 14px; }
.gallery-item { break-inside: avoid; margin-bottom: 14px; border-radius: var(--radius); overflow: hidden; cursor: pointer; position: relative; }
.gallery-item img { width: 100%; display: block; transition: transform 0.4s ease; }
.gallery-item:hover img { transform: scale(1.04); }
.gallery-overlay { position: absolute; inset: 0; background: rgba(79,70,229,0.18); opacity: 0; transition: opacity 0.3s; display: flex; align-items: center; justify-content: center; }
.gallery-overlay svg { color: white; }
.gallery-item:hover .gallery-overlay { opacity: 1; }

.lightbox { display: none; position: fixed; inset: 0; background: rgba(0,0,0,0.95); z-index: 9999; align-items: center; justify-content: center; padding: 20px; }
.lightbox.open { display: flex; }
.lightbox-content { max-width: 90vw; max-height: 90vh; text-align: center; }
.lightbox-content img { max-height: 80vh; border-radius: 8px; }
.lightbox-caption { color: #aaa; margin-top: 12px; font-size: 0.9rem; }
.lightbox-close { position: fixed; top: 20px; right: 24px; font-size: 1.8rem; color: white; cursor: pointer; width: 42px; height: 42px; display: flex; align-items: center; justify-content: center; border-radius: 50%; background: rgba(255,255,255,0.1); }
.lightbox-close:hover { background: rgba(255,255,255,0.2); }
.lightbox-nav { position: fixed; top: 50%; transform: translateY(-50%); font-size: 2rem; color: white; cursor: pointer; width: 50px; height: 50px; display: flex; align-items: center; justify-content: center; border-radius: 50%; background: rgba(255,255,255,0.1); }
.lightbox-prev { left: 20px; } .lightbox-next { right: 20px; }
.lightbox-nav:hover { background: rgba(79,70,229,0.4); }

/* ════════════════════ CONTACT ════════════════════ */
.contact-grid { display: grid; grid-template-columns: 1fr 1.5fr; gap: 56px; align-items: start; }
.contact-info { display: flex; flex-direction: column; gap: 18px; }
.contact-info-card { padding: 18px; border-radius: var(--radius); display: flex; align-items: flex-start; gap: 14px; }
.contact-info-card .c-icon { width: 42px; height: 42px; border-radius: 10px; background: rgba(79,70,229,0.08); border: 1px solid rgba(79,70,229,0.15); display: flex; align-items: center; justify-content: center; color: var(--accent); flex-shrink: 0; }
.contact-info-card h4 { font-size: 0.82rem; color: var(--accent); letter-spacing: 1px; margin-bottom: 4px; }
.contact-info-card p { font-size: 0.88rem; color: var(--text-muted); }
.contact-socials { display: flex; gap: 10px; margin-top: 6px; flex-wrap: wrap; }
.contact-form .form-group { margin-bottom: 18px; }
.contact-form label { display: block; font-size: 0.78rem; letter-spacing: 1px; text-transform: uppercase; color: var(--text-muted); margin-bottom: 7px; }
.contact-form input, .contact-form textarea { width: 100%; background: var(--card-bg); border: 1px solid var(--glass-border); border-radius: 8px; padding: 11px 15px; color: var(--text-bright); font-family: 'DM Sans', sans-serif; font-size: 1rem; outline: none; transition: var(--transition); }
.contact-form input:focus, .contact-form textarea:focus { border-color: var(--accent); box-shadow: 0 0 16px rgba(79,70,229,0.1); }
.contact-form textarea { resize: vertical; min-height: 120px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.map-container { border-radius: var(--radius); overflow: hidden; border: 1px solid var(--glass-border); height: 280px; }
.map-container iframe { width: 100%; height: 100%; border: none; }

/* ════════════════════ FOOTER ════════════════════ */
footer { background: var(--primary2); padding: 56px 0 20px; border-top: 1px solid var(--glass-border); }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr; gap: 44px; margin-bottom: 44px; }
.footer-about .footer-logo { font-family: 'Syne', sans-serif; font-size: 1.15rem; font-weight: 700; color: var(--text-bright); margin-bottom: 14px; }
.footer-about .footer-logo span { color: var(--accent); }
.footer-about p { font-size: 0.88rem; color: var(--text-muted); line-height: 1.6; margin-bottom: 18px; }
.footer-socials { display: flex; gap: 8px; }
.footer-socials a { width: 34px; height: 34px; border-radius: 50%; border: 1px solid var(--glass-border); display: flex; align-items: center; justify-content: center; color: var(--text-muted); transition: var(--transition); }
.footer-socials a:hover { border-color: var(--accent); color: var(--accent); }
.footer-col h4 { font-size: 0.78rem; letter-spacing: 2px; text-transform: uppercase; color: var(--accent); margin-bottom: 18px; }
.footer-col ul { list-style: none; display: flex; flex-direction: column; gap: 9px; }
.footer-col ul li a { font-size: 0.88rem; color: var(--text-muted); transition: var(--transition); }
.footer-col ul li a:hover { color: var(--accent); }
.footer-contact-item { display: flex; gap: 9px; align-items: flex-start; margin-bottom: 10px; }
.footer-contact-item .fi-icon { color: var(--accent); margin-top: 2px; }
.footer-contact-item span { font-size: 0.84rem; color: var(--text-muted); }
.footer-bottom { border-top: 1px solid var(--glass-border); padding-top: 20px; display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 10px; }
.footer-bottom p { font-size: 0.83rem; color: var(--text-muted); }
.visitor-count { font-family: 'JetBrains Mono', monospace; font-size: 0.78rem; color: var(--text-muted); display: flex; align-items: center; gap: 5px; }
.visitor-count span { color: var(--accent); }

/* ════════════════════ BACK TO TOP ════════════════════ */
.back-to-top { position: fixed; bottom: 28px; right: 28px; width: 42px; height: 42px; border-radius: 50%; background: transparent; color: var(--text-bright); color:black; font-size: 1.1rem; display: flex; align-items: center; justify-content: center; cursor: pointer; z-index: 100; box-shadow: 0 4px 16px rgba(79,70,229,0.3); opacity: 0; transform: translateY(20px); transition: var(--transition); }
.back-to-top.visible { opacity: 1; transform: translateY(0); }
.back-to-top:hover { transform: translateY(-4px) scale(1.05); }





/* ════════════════════ MODAL ════════════════════ */
.modal-overlay { display: none; position: fixed; inset: 0; background: rgba(0,0,0,0.7); z-index: 9000; align-items: center; justify-content: center; padding: 20px; }
.modal-overlay.open { display: flex; }
.modal-box { background: var(--primary); border: 1px solid var(--glass-border); border-radius: var(--radius); max-width: 680px; width: 100%; max-height: 80vh; overflow-y: auto; padding: 32px; position: relative; box-shadow: 0 20px 60px rgba(0,0,0,0.2); }
.modal-close { position: absolute; top: 14px; right: 18px; font-size: 1.4rem; color: var(--text-muted); cursor: pointer; width: 30px; height: 30px; display: flex; align-items: center; justify-content: center; border-radius: 50%; transition: var(--transition); }
.modal-close:hover { color: var(--accent3); }
.modal-box img { width: 100%; border-radius: 8px; margin-bottom: 18px; max-height: 280px; object-fit: cover; }
.modal-box h2 { font-size: 1.35rem; margin-bottom: 7px; }
.modal-box .modal-date { font-family: 'JetBrains Mono', monospace; font-size: 0.72rem; color: var(--accent); letter-spacing: 2px; margin-bottom: 14px; }
.modal-box .modal-content { font-size: 0.93rem; color: var(--text); line-height: 1.7; }

/* ════════════════════ TOAST ════════════════════ */
.toast { position: fixed; bottom: 28px; left: 50%; transform: translateX(-50%) translateY(100px); background: var(--card-bg); border: 1px solid var(--accent); border-radius: 50px; padding: 11px 26px; font-size: 0.88rem; color: var(--text-bright); z-index: 99999; transition: transform 0.4s cubic-bezier(0.4,0,0.2,1); display: flex; align-items: center; gap: 9px; box-shadow: 0 8px 30px rgba(0,0,0,0.15); }
.toast.show { transform: translateX(-50%) translateY(0); }
.toast.error { border-color: var(--accent3); }
.toast .toast-icon { font-size: 1rem; }

/* ════════════════════ SKELETON ════════════════════ */
.skeleton { background: linear-gradient(90deg, var(--card-bg) 25%, rgba(79,70,229,0.04) 50%, var(--card-bg) 75%); background-size: 400% 100%; animation: shimmer 1.5s infinite; border-radius: 8px; }
@keyframes shimmer { 0% { background-position: 100% 50%; } 100% { background-position: 0% 50%; } }
.skeleton-card { height: 260px; border-radius: var(--radius); }

/* ════════════════════ REVEAL ════════════════════ */
.reveal { opacity: 0; transform: translateY(32px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }

/* ════════════════════ EMPTY STATE ════════════════════ */
.empty-state { text-align: center; padding: 56px 20px; color: var(--text-muted); }
.empty-state .empty-icon { font-size: 2.5rem; margin-bottom: 14px; opacity: 0.4; }
.empty-state p { font-size: 0.97rem; }

/* ════════════════════ RESPONSIVE ════════════════════ */
@media (max-width: 1024px) {
  .research-grid { grid-template-columns: repeat(2, 1fr); }
  .people-grid { grid-template-columns: repeat(3, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
  .nav-links { display: none; }
  .hamburger { display: flex; }
  .hero-content { padding: calc(var(--nav-h) + 20px) 0 40px; }
  #home h1 { font-size: clamp(2rem, 8vw, 2.8rem); }
  .hero-trust-pills { gap: 8px; }
  .news-grid { grid-template-columns: 1fr; }
  .timeline::before { left: 18px; }
  .timeline-item { grid-template-columns: 38px 1fr; }
  .timeline-item:nth-child(odd) .timeline-content { grid-column: 2; text-align: left; }
  .timeline-item:nth-child(even) .timeline-content { grid-column: 2; }
  .timeline-item .timeline-empty { display: none; }
  .research-grid { grid-template-columns: 1fr 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .people-grid { grid-template-columns: repeat(2, 1fr); }
  .gallery-grid { columns: 2; }
  .footer-grid { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .research-grid { grid-template-columns: 1fr; }
  .people-grid { grid-template-columns: 1fr; }
  .gallery-grid { columns: 1; }
  .section-padding { padding: 60px 0; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}

/* ════════════════════ OVERFLOW FIXES ════════════════════ */
html, body {
  overflow-x: hidden;
  max-width: 100%;
}
#home { overflow: hidden; }
.hero-content { overflow: hidden; }

/* Prevent orbit rings from causing overflow on mobile */
@media (max-width: 768px) {
  .profile-orbit {
    width: 220px !important;
    height: 220px !important;
    overflow: visible;
  }
  .profile-photo { width: 150px !important; height: 150px !important; }
  .orbit-ring-1 { width: 190px !important; height: 190px !important; margin: -95px 0 0 -95px !important; }
  .orbit-ring-2 { width: 220px !important; height: 220px !important; margin: -110px 0 0 -110px !important; }
  /* Hero text tweaks */
  .hero-text { padding: 0 8px; }
  .hero-text h1 { font-size: clamp(1.7rem, 8vw, 2.4rem); }

  /* Nav logo shorter */
  .nav-logo span { font-size: 0.95rem; }
  /* Timeline mobile single column */
  .timeline::before { left: 20px; }
  .timeline-item {
    display: grid !important;
    grid-template-columns: 44px 1fr !important;
    grid-template-rows: auto !important;
  }
  .timeline-item .timeline-dot { grid-column: 1; grid-row: 1; padding-top: 0; }
  .timeline-item .timeline-content { grid-column: 2; grid-row: 1; text-align: left !important; }
  .timeline-item .timeline-empty { display: none !important; }
  /* People tabs wrap better */
  .people-tabs { gap: 6px; }
  .people-tab { padding: 6px 12px; font-size: 0.78rem; }
  /* Filter pills */
  .filter-pill { padding: 5px 12px; font-size: 0.75rem; }
  /* Contact form full padding */
  .contact-form.glass-card { padding: 20px !important; }
  /* Footer */
  .footer-bottom { flex-direction: column; align-items: flex-start; gap: 8px; }
  /* Pub controls stack */
  .pub-controls { flex-direction: column; align-items: stretch; }
  .pub-search { min-width: unset; }
  /* Section heading */
  .section-heading { margin-bottom: 40px; }
  .section-padding { padding: 72px 0; }
  /* Modal */
  .modal-box { padding: 20px; }
}

@media (max-width: 480px) {
  .nav-inner { padding: 0 16px; }
  .container { padding: 0 16px; }
  #home h1 { font-size: 1.7rem; }
  .hero-badge-pill { font-size: 0.72rem; padding: 5px 13px; }
  .hero-buttons { gap: 10px; }
  .hero-buttons .btn { flex: 1; justify-content: center; }
  .research-grid { grid-template-columns: 1fr !important; }
  .people-grid { grid-template-columns: 1fr !important; }
  .gallery-grid { columns: 1 !important; }
  .news-grid { grid-template-columns: 1fr !important; }
  .section-padding { padding: 56px 0; }
  .projects-accordion { padding: 0 4px; }
  .contact-grid { gap: 28px; }
  .form-row { grid-template-columns: 1fr !important; }
  .footer-grid { grid-template-columns: 1fr !important; }
  .footer-grid { gap: 28px; }
}

/* ════════════════════ EDUCATION ════════════════════ */

/* ══════════════════════════════════════
   ACTIVITIES GRID (edu-style)
══════════════════════════════════════ */
.activities-grid { max-width: 820px; margin: 0 auto; display: flex; flex-direction: column; gap: 20px; }
.act-item { display: flex; gap: 20px; align-items: flex-start; padding: 22px 24px; }
.act-left { display: flex; flex-direction: column; align-items: center; gap: 6px; min-width: 110px; text-align: center; flex-shrink: 0; }
.act-icon { display: flex; align-items: center; justify-content: center; width: 42px; height: 42px; border-radius: 10px; background: rgba(79,70,229,0.10); border: 1px solid rgba(79,70,229,0.18); color: var(--accent); flex-shrink: 0; }
.act-year { font-size: 0.72rem; color: var(--accent); font-family: monospace; font-weight: 600; line-height: 1.4; }
.act-right { flex: 1; min-width: 0; }
.act-type-badge { font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--accent2); font-weight: 600; margin-bottom: 5px; }
.act-title { font-size: 1rem; font-weight: 700; color: var(--text-bright); margin-bottom: 6px; }
.act-desc { font-size: 0.88rem; color: var(--text-muted); line-height: 1.6; margin-bottom: 8px; }
.act-position { display: inline-flex; align-items: center; gap: 5px; font-size: 0.83rem; color: var(--text-muted); margin-top: 6px; }
@media (max-width: 600px) {
  .act-item { flex-direction: column; gap: 14px; padding: 18px 16px; }
  .act-left { flex-direction: row; min-width: unset; justify-content: flex-start; gap: 10px; }
}
.edu-timeline { max-width: 820px; margin: 0 auto; display: flex; flex-direction: column; gap: 20px; }
.edu-item {
  display: flex; gap: 28px; align-items: flex-start;
  padding: 28px 32px; border-radius: var(--radius);
}
.edu-left { display: flex; flex-direction: column; align-items: center; gap: 8px; min-width: 110px; text-align: center; }
.edu-year {
  font-family: 'JetBrains Mono', monospace; font-size: 0.72rem;
  color: var(--accent); letter-spacing: 1.5px; background: rgba(79,70,229,0.08);
  border: 1px solid rgba(79,70,229,0.2); border-radius: 20px; padding: 3px 10px;
  white-space: nowrap;
}
.edu-icon { font-size: 1.5rem; }
.edu-right { flex: 1; }
.edu-degree { font-size: 1.05rem; font-weight: 700; margin-bottom: 4px; color: var(--text-bright); }
.edu-institution { font-size: 0.9rem; color: var(--accent2); font-style: italic; margin-bottom: 8px; }
.edu-desc { font-size: 0.88rem; color: var(--text-muted); line-height: 1.6; }

/* ════════════════════ SKILLS ════════════════════ */
#skills-container { max-width: 900px; margin: 0 auto; }
.skills-group { margin-bottom: 36px; }
.skills-cat-label {
  font-size: 0.75rem; font-weight: 700; letter-spacing: 2px; text-transform: uppercase;
  color: var(--accent); margin-bottom: 16px; display: flex; align-items: center; gap: 10px;
}
.skills-cat-label::after { content: ''; flex: 1; height: 1px; background: var(--glass-border); }
.skills-tags { display: flex; flex-wrap: wrap; gap: 12px; }
.skill-tag-wrap { display: flex; flex-direction: column; gap: 5px; min-width: 120px; }
.skill-tag {
  display: inline-block; padding: 6px 16px; border-radius: 20px; font-size: 0.82rem;
  font-weight: 600; background: var(--glass); border: 1px solid var(--glass-border);
  color: var(--text-bright); transition: var(--transition);
}
.skill-tag:hover { border-color: var(--accent); color: var(--accent); }
.skill-bar { height: 3px; background: var(--glass-border); border-radius: 2px; overflow: hidden; }
.skill-fill { height: 100%; background: linear-gradient(90deg, var(--accent), var(--accent2)); border-radius: 2px; transition: width 1s ease; }

@media (max-width: 600px) {
  .edu-item { flex-direction: column; gap: 14px; padding: 20px; }
  .edu-left { flex-direction: row; min-width: unset; justify-content: flex-start; }
}

/* ── Fixed bottom-left theme toggle ── */
.fixed-theme-btn {
  position: fixed;
  bottom: 24px;
  left: 24px;
  z-index: 9999;
  background: var(--card-bg);
  border: 1px solid var(--glass-border);
  color: var(--text);
  font-size: 0.75rem;
  font-family: 'Syne', sans-serif;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  padding: 7px 16px;
  border-radius: 20px;
  cursor: pointer;
  backdrop-filter: blur(10px);
  transition: all 0.2s;
  display: none;
}
.fixed-theme-btn:hover { border-color: var(--accent); color: var(--accent); }
@media (max-width: 1024px) {
  .fixed-theme-btn { display: block; }
  .theme-toggle { display: none; }
}
/* Activity position badge */
.activity-position {
  font-size: 0.82rem;
  color: var(--accent, #00e5ff);
  margin: 6px 0 4px;
  font-weight: 500;
  letter-spacing: 0.02em;
}

/* ── Gallery Preview (homepage) ── */
.gallery-preview-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; }
.gallery-preview-item { border-radius: var(--radius); overflow: hidden; cursor: pointer; position: relative; aspect-ratio: 1 / 1; }
.gallery-preview-item img { width: 100%; height: 100%; object-fit: cover; display: block; transition: transform 0.4s ease; }
.gallery-preview-item:hover img { transform: scale(1.06); }
.gallery-preview-item .gallery-overlay { position: absolute; inset: 0; background: rgba(0,0,0,0.35); display: flex; align-items: center; justify-content: center; opacity: 0; transition: opacity 0.3s; }
.gallery-preview-item:hover .gallery-overlay { opacity: 1; }
@media (max-width: 600px) { .gallery-preview-grid { grid-template-columns: repeat(2, 1fr); } }

/* ══════════════════════════════════════════
   NOTES SECTION — Homepage Preview
══════════════════════════════════════════ */
.notes-preview-wrap { margin-top: 16px; }

.notes-preview-card {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 36px;
  align-items: center;
  padding: 42px 48px;
  border-radius: var(--radius);
  border: 1px solid var(--glass-border);
  background: var(--card-bg);
  box-shadow: var(--shadow);
  transition: box-shadow 0.3s, transform 0.3s;
}

.notes-preview-card:hover {
  box-shadow: 0 8px 40px rgba(79,70,229,0.15);
  transform: translateY(-3px);
}

.notes-preview-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 90px;
  height: 90px;
  border-radius: 50%;
  background: linear-gradient(135deg, rgba(79,70,229,0.12), rgba(124,58,237,0.12));
  border: 1.5px solid var(--glass-border);
  color: var(--accent);
  flex-shrink: 0;
}

.notes-preview-text h3 {
  font-size: 1.4rem;
  margin-bottom: 10px;
  color: var(--text-bright);
}

.notes-preview-text p {
  color: var(--text-muted);
  font-size: 0.97rem;
  line-height: 1.7;
  margin-bottom: 16px;
}

.notes-feature-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.notes-feature-list li {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
  color: var(--text);
}

.notes-feature-list li svg {
  color: var(--accent);
  flex-shrink: 0;
}

.notes-preview-action { flex-shrink: 0; }

.notes-go-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 30px;
  font-size: 1rem;
  font-weight: 600;
  white-space: nowrap;
}

.notes-go-btn svg { transition: transform 0.25s ease; }
.notes-go-btn:hover svg { transform: translateX(4px); }

@media (max-width: 900px) {
  .notes-preview-card {
    grid-template-columns: 1fr;
    text-align: center;
    padding: 36px 28px;
    gap: 24px;
  }
  .notes-preview-icon { margin: 0 auto; }
  .notes-feature-list { align-items: center; }
  .notes-preview-action { display: flex; justify-content: center; }
}