/* ══════════════════════════════════════════════════════
   Khanh Ngo Portfolio · style.css  (Minimal Academic)
   ══════════════════════════════════════════════════════ */

:root {
  --accent: #0D9488;
  --text:   #111827;
  --muted:  #6b7280;
  --dim:    #9ca3af;
  --border: #e5e7eb;
  --bg:     #ffffff;
  --bg-alt: #f9fafb;
  --font:   'Inter', system-ui, sans-serif;
  --mono:   'JetBrains Mono', monospace;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  font-size: 15px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; }
a   { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
ul  { list-style: none; }

/* ── Scrollbar ── */
::-webkit-scrollbar { width: 4px; }
::-webkit-scrollbar-thumb { background: var(--border); }

/* ══════════════════════════════════════════════════════
   NAVIGATION
   ══════════════════════════════════════════════════════ */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
  padding: 0 2rem;
}
.nav-inner {
  max-width: 860px; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  height: 52px;
}
.nav-logo {
  font-family: var(--mono);
  font-size: 0.9rem; font-weight: 700;
  color: var(--accent);
}
.nav-links { display: flex; gap: 1.75rem; }
.nav-link {
  font-size: 0.85rem; font-weight: 500; color: var(--muted);
  transition: color 0.15s;
}
.nav-link:hover { color: var(--text); text-decoration: none; }

.nav-toggle {
  display: none; flex-direction: column; gap: 4px;
  background: none; border: none; cursor: pointer; padding: 4px;
}
.nav-toggle span {
  display: block; width: 20px; height: 1.5px;
  background: var(--muted); border-radius: 2px;
}

/* ══════════════════════════════════════════════════════
   HERO
   ══════════════════════════════════════════════════════ */
.hero-section {
  padding: 100px 2rem 60px;
  border-bottom: 1px solid var(--border);
}
.hero-bg-grid, .hero-glow { display: none; }

.hero-inner {
  max-width: 860px; margin: 0 auto;
  display: flex; gap: 3rem; align-items: flex-start;
}

/* Avatar */
.hero-avatar-wrap {
  flex-shrink: 0;
  display: flex; flex-direction: column; align-items: center; gap: 0.75rem;
}
.avatar-ring {
  width: 170px; height: 260px; border-radius: 14px;
  padding: 2px;
  background: var(--accent);
  overflow: hidden;
  box-shadow: none;
  animation: none;
}
.avatar-ring img {
  width: 100%; height: 100%; border-radius: 12px; object-fit: cover;
  background: var(--bg-alt);
}
.avatar-placeholder-inner {
  display: none;
  width: 100%; height: 100%; border-radius: 12px;
  background: #dbeafe;
  align-items: center; justify-content: center;
  font-size: 2.5rem; font-weight: 800; color: var(--accent);
}
.avatar-placeholder .avatar-placeholder-inner { display: flex; }
.avatar-placeholder img { display: none; }

.status-badge {
  display: flex; align-items: center; gap: 6px;
  font-size: 0.7rem; font-weight: 500; color: #059669;
  white-space: nowrap;
}
.status-dot {
  width: 6px; height: 6px; border-radius: 50%;
  background: #059669;
  animation: pulse-dot 2s ease-in-out infinite;
}
@keyframes pulse-dot {
  0%,100% { opacity: 1; }
  50%      { opacity: 0.4; }
}

/* Hero Content */
.hero-content { flex: 1; padding-top: 0.25rem; }
.hero-greeting {
  font-size: 0.8rem; color: var(--accent);
  font-family: var(--mono); letter-spacing: 0.5px;
  margin-bottom: 0.3rem; font-weight: 600;
}
.hero-name {
  font-size: 2rem; font-weight: 800; line-height: 1.15;
  color: var(--text); margin-bottom: 0.3rem;
}
.hero-title {
  font-size: 0.875rem; color: var(--muted);
  font-weight: 400; margin-bottom: 1rem;
  font-family: var(--mono); min-height: 1.5em;
}
.hero-bio {
  font-size: 0.9rem; color: var(--muted);
  max-width: 520px; line-height: 1.8; margin-bottom: 1.25rem;
  text-align: justify;
}
.hero-bio strong { color: var(--text); font-weight: 600; }

.hero-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 1.5rem; }
.tag {
  padding: 2px 10px; border-radius: 3px;
  background: #eff6ff; border: 1px solid #bfdbfe;
  font-size: 0.75rem; font-weight: 500; color: var(--accent);
}

.hero-actions { display: flex; gap: 0.75rem; margin-bottom: 1.5rem; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 7px 18px; border-radius: 6px;
  font-size: 0.83rem; font-weight: 600;
  transition: all 0.15s; cursor: pointer;
  border: 1px solid transparent;
}
.btn-primary  { background: var(--accent); color: #fff; }
.btn-primary:hover  { background: #1740b0; text-decoration: none; }
.btn-secondary { background: transparent; color: var(--text); border-color: var(--border); }
.btn-secondary:hover { background: var(--bg-alt); text-decoration: none; }

.hero-socials { display: flex; gap: 0.6rem; }
.social-link {
  width: 32px; height: 32px; border-radius: 6px;
  display: flex; align-items: center; justify-content: center;
  background: transparent; border: 1px solid var(--border);
  color: var(--muted); transition: all 0.15s;
}
.social-link svg { width: 15px; height: 15px; }
.social-link:hover {
  color: var(--accent); border-color: var(--accent);
  background: #eff6ff;
}

/* ══════════════════════════════════════════════════════
   SHARED SECTION
   ══════════════════════════════════════════════════════ */
.section     { padding: 64px 2rem; }
.section-alt { background: var(--bg-alt); }
.container   { max-width: 860px; margin: 0 auto; }

.section-header { margin-bottom: 2.5rem; }
.pub-section-header {
  display: flex; align-items: flex-start; justify-content: space-between; gap: 1.5rem;
  margin-bottom: 2.5rem;
}
.pub-header-text { flex: 1; }
.pub-header-img {
  height: 200px; width: auto;
  object-fit: contain;
  flex-shrink: 0;
  border-radius: 8px;
  align-self: center;
  margin-top: 0;
}
.section-mascot-img:not([src]), .section-mascot-img[src=""] { display: none; }
.section-label { display: none; }
.section-title {
  font-size: 1.35rem; font-weight: 700; color: var(--text);
  padding-bottom: 0.6rem;
  border-bottom: 2px solid var(--accent);
  display: inline-block;
  margin-bottom: 0.4rem;
}
.section-sub {
  font-size: 0.875rem; color: var(--muted); margin-top: 0.4rem;
}
.section-header::after { display: none; }

/* ══════════════════════════════════════════════════════
   AWARDS
   ══════════════════════════════════════════════════════ */
.awards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1rem;
}
.award-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  transition: box-shadow 0.15s;
}
.award-card:hover { box-shadow: 0 2px 8px rgba(0,0,0,0.08); }
.award-img-wrap {
  width: 100%; height: 150px;
  background: var(--bg-alt);
  overflow: hidden;
}
.award-img-wrap img { width: 100%; height: 100%; object-fit: cover; }
.award-body { padding: 1rem; }
.award-rank {
  display: inline-block;
  padding: 2px 9px; border-radius: 4px;
  font-size: 0.68rem; font-weight: 700;
  margin-bottom: 0.4rem;
  letter-spacing: 0.3px;
}
.rank-first       { background: #fefce8; color: #854d0e; border: 1px solid #fde68a; }
.rank-second      { background: #f1f5f9; color: #475569; border: 1px solid #cbd5e1; }
.rank-third       { background: #fff7ed; color: #9a3412; border: 1px solid #fed7aa; }
.rank-consolation { background: #f0fdf4; color: #166534; border: 1px solid #bbf7d0; }
.award-title { font-size: 0.9rem; font-weight: 700; margin-bottom: 0.2rem; }
.award-org   { font-size: 0.75rem; color: var(--accent); font-weight: 600; margin-bottom: 0.3rem; }
.award-desc  { font-size: 0.8rem; color: var(--muted); }

.placeholder-img {
  width: 100%; height: 100%;
  display: flex; flex-direction: column;
  align-items: center; justify-content: center; gap: 0.4rem;
  color: var(--dim); font-size: 0.75rem;
}
.placeholder-img svg { width: 28px; height: 28px; opacity: 0.3; }
.placeholder-img.large svg { width: 36px; height: 36px; }

/* ══════════════════════════════════════════════════════
   PUBLICATIONS
   ══════════════════════════════════════════════════════ */
.pub-filters {
  display: flex; gap: 0.4rem;
  margin-bottom: 2rem; flex-wrap: wrap;
}
.pub-filter {
  padding: 4px 14px; border-radius: 4px;
  background: transparent; border: 1px solid var(--border);
  color: var(--muted); font-size: 0.8rem; font-weight: 500;
  cursor: pointer; transition: all 0.15s;
  font-family: var(--font);
}
.pub-filter:hover { border-color: var(--muted); color: var(--text); }
.pub-filter.active { background: var(--accent); border-color: var(--accent); color: #fff; }

.pub-group { margin-bottom: 2.5rem; }
.pub-group-title {
  font-size: 0.78rem; font-weight: 700; color: var(--dim);
  text-transform: uppercase; letter-spacing: 1.5px;
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.5rem; margin-bottom: 1rem;
}

.pub-list { display: flex; flex-direction: column; gap: 0.75rem; }

/* ── Publication Card ── */
.pub-card {
  display: flex;
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  background: var(--bg);
  transition: box-shadow 0.15s, border-color 0.15s;
}
.pub-card:hover {
  border-color: #d1d5db;
  box-shadow: 0 2px 8px rgba(0,0,0,0.07);
}

.pub-thumb {
  flex-shrink: 0;
  width: 180px;
  background: var(--bg-alt);
  display: flex; align-items: center; justify-content: center;
  flex-direction: column; gap: 0.4rem;
  position: relative; overflow: hidden;
}
.pub-thumb img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform 0.3s;
}
.pub-card:hover .pub-thumb img { transform: scale(1.03); }
.pub-thumb-placeholder { background: var(--bg-alt); }
.pub-thumb-icon {
  color: var(--dim); opacity: 0.4;
}
.pub-thumb img + .pub-thumb-icon { display: none; }
.pub-thumb-icon svg { width: 28px; height: 28px; }
.thumb-label { font-size: 0.65rem; color: var(--dim); text-align: center; padding: 0 8px; }

.pub-body {
  flex: 1; padding: 1rem 1.1rem;
  display: flex; flex-direction: column; gap: 0.35rem;
  justify-content: center;
  border-left: 1px solid var(--border);
}
.pub-title { font-size: 0.9rem; font-weight: 700; line-height: 1.4; color: var(--text); }
.pub-authors { font-size: 0.8rem; color: var(--muted); }
.author-me   { color: var(--accent); font-weight: 600; }
.pub-venue   { display: flex; flex-wrap: wrap; gap: 5px; align-items: center; font-size: 0.78rem; }
.venue-name  { color: var(--muted); font-style: italic; }
.pub-year    { color: var(--dim); }

.pub-equal-note { font-size: 0.72rem; color: var(--muted); font-style: italic; }

.venue-rank {
  padding: 1px 7px; border-radius: 3px; font-size: 0.68rem;
  font-weight: 600; font-style: normal;
}
.rank-q1    { background: #ecfdf5; color: #065f46; border: 1px solid #a7f3d0; }
.rank-q2    { background: #eff6ff; color: #1e40af; border: 1px solid #bfdbfe; }
.rank-conf  { background: #fffbeb; color: #92400e; border: 1px solid #fde68a; }
.rank-journal { background: #f5f3ff; color: #4c1d95; border: 1px solid #ddd6fe; }

.pub-status {
  display: inline-flex; align-items: center;
  padding: 1px 8px; border-radius: 3px; width: fit-content;
  font-size: 0.68rem; font-weight: 600;
}
.status-published { background: #ecfdf5; color: #059669; border: 1px solid #a7f3d0; }
.status-accepted  { background: #eff6ff; color: #2563eb; border: 1px solid #bfdbfe; }
.status-revision  { background: #fffbeb; color: #d97706; border: 1px solid #fde68a; }
.status-review    { background: #f5f3ff; color: #7c3aed; border: 1px solid #ddd6fe; }

.pub-links { display: flex; flex-wrap: wrap; gap: 5px; margin-top: 0.2rem; }
.pub-link {
  display: inline-flex; align-items: center; gap: 4px;
  padding: 3px 10px; border-radius: 4px;
  background: transparent; border: 1px solid var(--border);
  font-size: 0.75rem; font-weight: 600; color: var(--muted);
  transition: all 0.15s;
}
.pub-link svg { width: 12px; height: 12px; }
.pub-link:hover {
  background: #eff6ff; border-color: var(--accent); color: var(--accent);
  text-decoration: none;
}

.pub-card.hidden { display: none; }

/* ══════════════════════════════════════════════════════
   PROJECTS
   ══════════════════════════════════════════════════════ */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1rem;
}
.project-card {
  background: var(--bg); border: 1px solid var(--border);
  border-radius: 8px; overflow: hidden;
  transition: box-shadow 0.15s, border-color 0.15s;
}
.project-card:hover { box-shadow: 0 2px 8px rgba(0,0,0,0.08); border-color: #d1d5db; }
.project-thumb { width: 100%; height: 170px; overflow: hidden; background: var(--bg-alt); }
.project-thumb img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.3s; }
.project-card:hover .project-thumb img { transform: scale(1.04); }
.placeholder-img.large { height: 100%; font-size: 0.75rem; color: var(--dim); }

.project-body { padding: 1rem; }
.project-tags { display: flex; flex-wrap: wrap; gap: 4px; margin-bottom: 0.5rem; }
.project-tag {
  padding: 1px 8px; border-radius: 3px;
  background: #eff6ff; border: 1px solid #bfdbfe;
  font-size: 0.68rem; font-weight: 600; color: var(--accent);
}
.project-title { font-size: 0.9rem; font-weight: 700; margin-bottom: 0.35rem; }
.project-desc  { font-size: 0.82rem; color: var(--muted); margin-bottom: 0.75rem; line-height: 1.6; }
.project-links { display: flex; gap: 5px; flex-wrap: wrap; }

/* ══════════════════════════════════════════════════════
   CONTACT
   ══════════════════════════════════════════════════════ */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 0.75rem;
}
.contact-card {
  display: flex; flex-direction: column; align-items: center;
  gap: 0.5rem; padding: 1.5rem 1rem;
  background: var(--bg); border: 1px solid var(--border);
  border-radius: 8px; text-align: center;
  transition: all 0.15s; cursor: pointer;
}
.contact-card:hover { border-color: var(--accent); background: #f8faff; }
.contact-icon {
  width: 40px; height: 40px; border-radius: 8px;
  background: #eff6ff;
  display: flex; align-items: center; justify-content: center;
  color: var(--accent);
}
.contact-icon svg { width: 20px; height: 20px; }
.contact-label { font-size: 0.68rem; font-weight: 700; color: var(--dim); text-transform: uppercase; letter-spacing: 1px; }
.contact-value { font-size: 0.82rem; font-weight: 500; color: var(--muted); }

/* ══════════════════════════════════════════════════════
   FOOTER
   ══════════════════════════════════════════════════════ */
.footer {
  padding: 1.5rem 2rem;
  border-top: 1px solid var(--border);
  text-align: center;
}
.footer-text { font-size: 0.8rem; color: var(--dim); }

/* ══════════════════════════════════════════════════════
   SCROLL REVEAL
   ══════════════════════════════════════════════════════ */
[data-reveal] { opacity: 0; transform: translateY(16px); transition: opacity 0.4s ease, transform 0.4s ease; }
[data-reveal].revealed { opacity: 1; transform: translateY(0); }

/* ══════════════════════════════════════════════════════
   RESPONSIVE
   ══════════════════════════════════════════════════════ */
@media (max-width: 700px) {
  .nav-links { display: none; }
  .nav-links.open {
    display: flex; flex-direction: column;
    position: absolute; top: 52px; left: 0; right: 0;
    background: rgba(255,255,255,0.98);
    border-bottom: 1px solid var(--border);
    padding: 1rem 2rem; gap: 1rem;
  }
  .nav-toggle { display: flex; }

  .hero-inner { flex-direction: column; gap: 1.5rem; }
  .avatar-ring { width: 130px; height: 165px; border-radius: 12px; }

  .pub-card { flex-direction: column; }
  .pub-thumb { width: 100%; height: 150px; }
  .pub-body  { border-left: none; border-top: 1px solid var(--border); }

  .section { padding: 48px 1.25rem; }
  .hero-section { padding: 80px 1.25rem 48px; }
}

@media (max-width: 480px) {
  .awards-grid, .projects-grid, .contact-grid { grid-template-columns: 1fr; }
}