/* ═══════════════════════════════════════════════════════════════════════
   styles.css — Utathya Aich Academic Portfolio
   Minimal, Jon Barron-inspired single-column layout.
   No external UI frameworks. Works on all modern browsers.
   ═══════════════════════════════════════════════════════════════════════ */

/* ── Reset ──────────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

/* ── Custom properties ──────────────────────────────────────────────── */
:root {
  --blue:       #1772d0;
  --blue-dark:  #0e5aaa;
  --text:       #1a1a1a;
  --muted:      #555;
  --light:      #888;
  --border:     #e6e6e6;
  --bg:         #ffffff;
  --chip-bg:    #eef3fd;
  --chip-bdr:   #c5d5f5;
  --chip-text:  #1d4ed8;
  --max-w:      900px;
  --nav-h:      86px;
}

/* ── Base ───────────────────────────────────────────────────────────── */
html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI',
               Helvetica, Arial, sans-serif;
  font-size:   15px;
  line-height: 1.7;
  color:       var(--text);
  background:  var(--bg);
}

a                { color: var(--blue); text-decoration: none; }
a:hover          { text-decoration: underline; color: var(--blue-dark); }
img              { max-width: 100%; display: block; }
ul               { list-style: none; }

/* ── Layout ─────────────────────────────────────────────────────────── */
.container {
  max-width: var(--max-w);
  margin:    0 auto;
  padding:   0 28px;
}

/* ── Navigation ─────────────────────────────────────────────────────── */
nav {
  position:        sticky;
  top:             0;
  z-index:         100;
  background:      rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom:   1px solid var(--border);
}

.nav-inner {
  max-width:       var(--max-w);
  margin:          0 auto;
  padding:         8px 28px 10px;
  min-height:      var(--nav-h);
  display:         flex;
  flex-direction:  column;
  align-items:     center;
  justify-content: center;
  gap:             8px;
}

.nav-brand {
  font-weight: 800;
  font-size:   26px;
  letter-spacing: 0.2px;
  line-height: 1;
  color:       var(--text);
}

.nav-brand:hover { text-decoration: none; color: var(--blue); }

.nav-links {
  display:    flex;
  gap:        8px;
  flex-wrap:  wrap;
  justify-content: center;
  list-style: none;
}

.nav-links a {
  font-size:      12px;
  font-weight:    600;
  color:          #556070;
  padding:        3px 10px;
  border:         1px solid #e3e8ef;
  border-radius:  999px;
  background:     #f7f9fc;
  text-decoration: none;
}

.nav-links a:hover {
  color:           var(--blue);
  border-color:    #b7cff2;
  background:      #eef4ff;
  text-decoration: none;
}

/* ── Sections ───────────────────────────────────────────────────────── */
section {
  padding:    52px 0;
  border-top: 1px solid var(--border);
}

#hero { border-top: none; padding-top: 60px; }

.section-title {
  font-size:     21px;
  font-weight:   700;
  color:         var(--text);
  margin-bottom: 26px;
}

/* ── Hero ───────────────────────────────────────────────────────────── */
.hero-layout {
  display:     flex;
  gap:         48px;
  align-items: flex-start;
}

.hero-photo img {
  width:         170px;
  height:        170px;
  border-radius: 50%;
  object-fit:    cover;
  flex-shrink:   0;
  border:        2px solid var(--border);
}

.hero-name {
  font-size:     30px;
  font-weight:   700;
  line-height:   1.2;
  margin-bottom: 8px;
}

.hero-title {
  font-size:     14.5px;
  color:         var(--muted);
  margin-bottom: 18px;
  line-height:   1.5;
}

.hero-bio {
  font-size:     15px;
  line-height:   1.8;
  color:         var(--text);
  margin-bottom: 24px;
  max-width:     540px;
}

.hero-bio strong { font-weight: 600; }

.hero-highlights {
  max-width:     560px;
  margin-bottom: 18px;
}

.hero-highlight {
  max-width:     560px;
  margin-bottom: 10px;
  padding:       11px 14px;
  border-radius: 12px;
  border:        1px solid;
  border-left:   4px solid;
  font-size:     13.8px;
  line-height:   1.55;
}

.hero-highlight:last-child {
  margin-bottom: 0;
}

.hero-highlight-phd {
  border-color: #bfddff;
  border-left-color: #1772d0;
  background: linear-gradient(95deg, #e9f4ff 0%, #f4f9ff 56%, #ffffff 100%);
  box-shadow: 0 6px 18px rgba(23, 114, 208, 0.08);
  color: #12385f;
}

.hero-highlight-collab {
  border-color: #bde9d1;
  border-left-color: #0e8a4a;
  background: linear-gradient(95deg, #ecfff4 0%, #f6fff9 56%, #ffffff 100%);
  box-shadow: 0 6px 18px rgba(14, 138, 74, 0.08);
  color: #11482d;
}

.hero-highlight-phd strong {
  font-weight: 700;
  color: #0b4f93;
}

.hero-highlight-collab strong {
  font-weight: 700;
  color: #0f6e3d;
}

/* ── Hero link buttons ──────────────────────────────────────────────── */
.hero-links {
  display:   flex;
  flex-wrap: wrap;
  gap:       8px;
}

.hero-link {
  display:         inline-block;
  padding:         5px 15px;
  border:          1px solid #ccc;
  border-radius:   20px;
  font-size:       13.5px;
  font-weight:     500;
  color:           var(--muted);
  background:      #fafafa;
  transition:      border-color 0.15s, color 0.15s, background 0.15s;
  text-decoration: none;
}

.hero-link:hover {
  border-color:    var(--blue);
  color:           var(--blue);
  background:      var(--chip-bg);
  text-decoration: none;
}

/* ── Current Work ───────────────────────────────────────────────────── */
.work-grid {
  display:               grid;
  grid-template-columns: 1fr 1fr;
  gap:                   14px;
}

.work-card {
  border:        1px solid var(--border);
  border-left:   3px solid var(--blue);
  border-radius: 6px;
  padding:       18px 20px;
}

.work-card-header {
  display:         flex;
  align-items:     flex-start;
  justify-content: space-between;
  gap:             10px;
  margin-bottom:   8px;
}

.work-card-title {
  font-size:   14.5px;
  font-weight: 600;
  color:       var(--text);
  line-height: 1.4;
}

.work-card-desc {
  font-size:   13.5px;
  color:       var(--muted);
  line-height: 1.65;
}

/* Status badges */
.status-badge {
  flex-shrink:    0;
  font-size:      10.5px;
  font-weight:    700;
  padding:        2px 9px;
  border-radius:  20px;
  white-space:    nowrap;
  text-transform: uppercase;
  letter-spacing: 0.3px;
}

.badge-ongoing  { background: #dbeafe; color: #1d4ed8; }
.badge-review   { background: #fef3c7; color: #92400e; }
.badge-accepted { background: #dcfce7; color: #166534; }
.badge-released { background: #ede9fe; color: #5b21b6; }

/* ── Research Statement ─────────────────────────────────────────────── */
.statement-block {
  max-width: 700px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.statement-block p {
  font-size: 15px;
  line-height: 1.85;
  color: var(--text);
}

.statement-block strong {
  font-weight: 650;
  color: #0f3060;
}

/* ── Research Interests ─────────────────────────────────────────────── */
.interests-wrap {
  display:   flex;
  flex-wrap: wrap;
  gap:       9px;
}

.interest-chip {
  padding:       6px 16px;
  background:    var(--chip-bg);
  border:        1px solid var(--chip-bdr);
  border-radius: 20px;
  font-size:     13.5px;
  font-weight:   500;
  color:         var(--chip-text);
}

/* ── Publication list ───────────────────────────────────────────────── */
.pub-list { display: flex; flex-direction: column; }

.pub-item {
  display:               grid;
  grid-template-columns: 58px 1fr;
  gap:                   0 14px;
  padding:               16px 0;
  border-bottom:         1px solid var(--border);
}

.pub-item:first-child { border-top: 1px solid var(--border); }

.pub-side {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
}

.paper-tile {
  width: 42px;
  height: 42px;
  border-radius: 10px;
  border: 1px solid;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.5px;
  line-height: 1;
  user-select: none;
}

.tile-conference { background: #eaf2ff; border-color: #9fc3ff; color: #1e40af; }
.tile-workshop   { background: #edfdf3; border-color: #9ce6ba; color: #166534; }
.tile-journal    { background: #fff8e6; border-color: #f5cf84; color: #92400e; }
.tile-challenge  { background: #fff0ef; border-color: #f9b5b2; color: #991b1b; }
.tile-preprint   { background: #f3f4f6; border-color: #d1d5db; color: #4b5563; }

.pub-year-label {
  font-size:   12.5px;
  color:       var(--light);
  font-weight: 500;
  padding-top: 3px;
}

.pub-title {
  font-size:     14.5px;
  font-weight:   600;
  color:         var(--text);
  line-height:   1.45;
  margin-bottom: 4px;
}

.pub-authors {
  font-size:     13px;
  color:         var(--muted);
  margin-bottom: 2px;
}

.pub-authors strong { color: var(--text); font-weight: 600; }

.pub-venue {
  font-size: 12.5px;
  color:     var(--light);
  font-style: italic;
}

/* ── Per-paper link buttons ─────────────────────────────────────────── */
.pub-links {
  display:    flex;
  flex-wrap:  wrap;
  gap:        6px;
  margin-top: 8px;
}

.pub-link-btn {
  font-size:       12px;
  padding:         3px 10px;
  border:          1px solid var(--border);
  border-radius:   4px;
  color:           var(--blue);
  background:      #fafafa;
  text-decoration: none;
  transition:      border-color 0.12s, background 0.12s;
}

.pub-link-btn:hover {
  border-color:    var(--blue);
  background:      var(--chip-bg);
  text-decoration: none;
}

/* ── Paper type tags ────────────────────────────────────────────────── */
.pub-type-tag {
  display:        inline-block;
  font-size:      10.5px;
  font-weight:    600;
  padding:        1px 7px;
  border-radius:  3px;
  margin-left:    7px;
  vertical-align: middle;
  border:         1px solid;
}

.tag-conference { border-color: #bfdbfe; color: #1d4ed8; background: #eff6ff; }
.tag-workshop   { border-color: #bbf7d0; color: #065f46; background: #f0fdf4; }
.tag-journal    { border-color: #fde68a; color: #92400e; background: #fffbeb; }
.tag-challenge  { border-color: #fecaca; color: #991b1b; background: #fef2f2; }
.tag-preprint   { border-color: #d1d5db; color: #6b7280; background: #f9fafb; }

/* ── News feed (featured publications displayed as news items) ──────── */
.news-scroll {
  max-height:     420px;
  overflow-y:     auto;
  border:         1px solid var(--border);
  border-radius:  8px;
  /* thin custom scrollbar */
  scrollbar-width: thin;
  scrollbar-color: #d1d5db transparent;
}

.news-scroll::-webkit-scrollbar        { width: 5px; }
.news-scroll::-webkit-scrollbar-track  { background: transparent; }
.news-scroll::-webkit-scrollbar-thumb  { background: #d1d5db; border-radius: 3px; }
.news-scroll::-webkit-scrollbar-thumb:hover { background: #b0b7c3; }

.news-item {
  display:               grid;
  grid-template-columns: 76px 1fr;
  gap:                   0 14px;
  padding:               14px 18px;
  border-bottom:         1px solid var(--border);
  transition:            background 0.12s;
}

.news-item:last-child  { border-bottom: none; }
.news-item:hover       { background: #fafbff; }

.news-meta {
  display:        flex;
  flex-direction: column;
  align-items:    flex-start;
  gap:            5px;
  padding-top:    2px;
}

.news-meta .paper-tile {
  margin-bottom: 2px;
}

.news-item.top-highlight-1 {
  background:  #eef6ff;
  border-left: 4px solid #1d4ed8;
}

.news-item.top-highlight-2 {
  background:  #f0fdf4;
  border-left: 4px solid #15803d;
}

.news-item.top-highlight-3 {
  background:  #fff7e8;
  border-left: 4px solid #b45309;
}

.news-year {
  font-size:   12px;
  font-weight: 700;
  color:       var(--light);
  white-space: nowrap;
}

.news-title {
  font-size:     14px;
  font-weight:   600;
  color:         var(--text);
  line-height:   1.45;
  margin-bottom: 4px;
}

.news-authors {
  font-size:     12.5px;
  color:         var(--muted);
  margin-bottom: 2px;
}

.news-authors strong { color: var(--text); font-weight: 600; }

.news-venue {
  font-size:  12px;
  color:      var(--light);
  font-style: italic;
}

/* ── Show More button ───────────────────────────────────────────────── */
.show-more-wrap { margin-top: 20px; text-align: center; }

.btn-show-more {
  padding:       8px 26px;
  border:        1px solid #ccc;
  border-radius: 20px;
  background:    transparent;
  font-family:   inherit;
  font-size:     14px;
  font-weight:   500;
  color:         var(--blue);
  cursor:        pointer;
  transition:    border-color 0.15s;
}

.btn-show-more:hover { border-color: var(--blue); }

/* ── Year tabs ──────────────────────────────────────────────────────── */
.year-tabs {
  display:                   flex;
  border-bottom:             2px solid var(--border);
  margin-bottom:             24px;
  overflow-x:                auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width:           none;
}

.year-tabs::-webkit-scrollbar { display: none; }

.year-tab-btn {
  padding:       10px 22px;
  border:        none;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  background:    transparent;
  font-family:   inherit;
  font-size:     15px;
  font-weight:   600;
  color:         var(--muted);
  cursor:        pointer;
  white-space:   nowrap;
  transition:    color 0.12s, border-color 0.12s;
}

.year-tab-btn:hover { color: var(--blue); }

.year-tab-btn.active {
  color:              var(--blue);
  border-bottom-color: var(--blue);
}

.year-tab-pane        { display: none; }
.year-tab-pane.active { display: block; }

.view-all-wrap { padding: 18px 0 4px; text-align: center; }

.btn-view-all {
  font-size:   14px;
  font-weight: 500;
  color:       var(--blue);
}

/* ── Mentorship section ─────────────────────────────────────────────── */
.mentor-tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 14px;
}

.mentor-tab-btn {
  padding: 6px 14px;
  border: 1px solid #c7d8ee;
  border-radius: 999px;
  background: #f7fbff;
  color: #21507f;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, color 0.15s;
}

.mentor-tab-btn:hover {
  border-color: #93b7e3;
}

.mentor-tab-btn.active {
  background: #1d4f8f;
  border-color: #1d4f8f;
  color: #fff;
}

.mentor-tab-pane {
  display: none;
}

.mentor-tab-pane.active {
  display: block;
}

.mentor-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.mentor-heading {
  font-size: 15px;
  font-weight: 700;
  color: #0f355f;
  margin-bottom: 2px;
}

.mentor-card {
  border: 1px solid #d9e4f3;
  border-left: 4px solid #3b82f6;
  border-radius: 10px;
  padding: 12px 14px;
  background: linear-gradient(100deg, #f4f9ff 0%, #ffffff 70%);
}

.mentor-name {
  font-size: 14.5px;
  font-weight: 700;
  color: var(--text);
  line-height: 1.35;
}

.mentor-affil {
  font-size: 12.5px;
  color: var(--light);
  margin-top: 1px;
}

.mentor-note,
.mentor-now {
  font-size: 13.5px;
  color: var(--muted);
  margin-top: 7px;
  line-height: 1.6;
}

.mentor-ref {
  font-size: 13px;
  color: #1e3a5f;
  margin-top: 8px;
}

.mentor-ref a {
  font-weight: 500;
}

/* ── Academic services ─────────────────────────────────────────────── */
.service-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.service-card {
  border: 1px solid #dbe7f7;
  border-left: 4px solid #2563eb;
  border-radius: 10px;
  padding: 13px 14px;
  background: linear-gradient(100deg, #f3f8ff 0%, #ffffff 70%);
}

.service-title {
  font-size: 14.5px;
  font-weight: 700;
  color: #133e72;
  line-height: 1.35;
}

.service-desc {
  margin-top: 6px;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--muted);
}

/* ── Awards ────────────────────────────────────────────────────────── */
.award-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.award-card {
  border: 1px solid #eadfbe;
  border-left: 4px solid #b7791f;
  border-radius: 10px;
  padding: 13px 14px;
  background: linear-gradient(100deg, #fff9ec 0%, #ffffff 70%);
}

.award-year {
  display: inline-block;
  padding: 1px 8px;
  border-radius: 999px;
  background: #f6e4bc;
  color: #734b12;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.25px;
  margin-bottom: 7px;
}

.award-title {
  font-size: 14.5px;
  font-weight: 700;
  color: #6f4610;
  line-height: 1.35;
}

.award-desc {
  margin-top: 6px;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--muted);
}

/* ── Hobbies ───────────────────────────────────────────────────────── */
.hobby-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.hobby-card {
  border: 1px solid #d8e6df;
  border-left: 4px solid #2f855a;
  border-radius: 10px;
  padding: 13px 14px;
  background: linear-gradient(100deg, #f2fbf6 0%, #ffffff 70%);
}

.hobby-title {
  font-size: 14.5px;
  font-weight: 700;
  color: #1f5f43;
  line-height: 1.35;
}

.hobby-desc {
  margin-top: 6px;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--muted);
}

/* ── Contact section ────────────────────────────────────────────────── */
.contact-block {
  font-size:   15px;
  line-height: 1.8;
  color:       var(--muted);
  max-width:   540px;
}

.contact-email {
  display:    inline-block;
  margin-top: 12px;
  font-size:  15px;
}

/* ── Footer ─────────────────────────────────────────────────────────── */
footer {
  border-top: 1px solid var(--border);
  padding:    26px 0 40px;
}

.footer-inner {
  display:         flex;
  align-items:     center;
  justify-content: space-between;
  flex-wrap:       wrap;
  gap:             10px;
}

.footer-left  { font-size: 13.5px; color: var(--muted); }
.footer-left strong { color: var(--text); }
.footer-right { font-size: 13px; color: var(--light); }

/* ── Year page specifics ────────────────────────────────────────────── */
.year-page-header { padding: 44px 0 28px; }

.year-page-title {
  font-size:     24px;
  font-weight:   700;
  margin-bottom: 10px;
}

.year-page-back { font-size: 14px; font-weight: 500; }

.year-page-divider {
  border:     none;
  border-top: 1px solid var(--border);
  margin:     32px 0 0;
}

/* ── Abstract text (year pages) ─────────────────────────────────────── */
.pub-abstract {
  font-size:   13.5px;
  color:       var(--muted);
  margin-top:  9px;
  line-height: 1.65;
}

/* ── Note text ──────────────────────────────────────────────────────── */
.pub-note {
  font-size: 13px;
  color:     var(--light);
  margin-bottom: 18px;
}

/* ── Responsive ─────────────────────────────────────────────────────── */
@media (max-width: 680px) {
  .container { padding: 0 18px; }

  .nav-inner {
    padding: 8px 16px 10px;
    gap: 7px;
  }

  .nav-brand {
    font-size: 22px;
  }

  .nav-links {
    gap: 6px;
  }

  .nav-links a {
    font-size: 11.5px;
    padding: 3px 9px;
  }

  .hero-layout {
    flex-direction: column;
    align-items:    center;
    text-align:     center;
    gap:            22px;
  }

  .hero-bio    { max-width: 100%; }
  .hero-highlights,
  .hero-highlight { text-align: center; }
  .hero-links  { justify-content: center; }

  .work-grid   { grid-template-columns: 1fr; }
  .mentor-tabs  { justify-content: center; }
  .mentor-col   { grid-template-columns: 1fr; }
  .service-grid { grid-template-columns: 1fr; }
  .award-grid   { grid-template-columns: 1fr; }
  .hobby-grid   { grid-template-columns: 1fr; }

  /* news items: collapse meta column on small screens */
  .news-item { grid-template-columns: 72px 1fr; }
  .news-scroll { max-height: 360px; }

  .year-tab-btn { padding: 10px 14px; font-size: 14px; }

  .footer-inner { flex-direction: column; align-items: flex-start; gap: 6px; }
}

@media (max-width: 440px) {
  .container    { padding: 0 14px; }
  section       { padding: 38px 0; }
  #hero         { padding-top: 40px; }
  .hero-photo img { width: 130px; height: 130px; }
  .hero-name    { font-size: 24px; }
  .section-title { font-size: 19px; }
  .nav-brand    { font-size: 20px; }
  .nav-links    { gap: 5px; }
  .nav-links a  { font-size: 11px; padding: 2px 8px; }
  .pub-item     { grid-template-columns: 52px 1fr; }
  .paper-tile   { width: 36px; height: 36px; font-size: 11px; }
}