:root{
  --bg:#ffffff;
  --fg:#111827;
  --muted:#6b7280;
  --border:#e5e7eb;
  --soft:#f9fafb;
  --link:#2563eb;
  --link2:#25EB46FF;
  --card:#ffffff;
  --shadow: 0 1px 2px rgba(0,0,0,.04);
}

:root[data-theme="dark"]{
  --bg:#0b1220;
  --fg:#e5e7eb;
  --muted:#a1a1aa;
  --border:#1f2937;
  --soft:#0f172a;
  --link:#93c5fd;
  --link2: #5be874;
  --card:#0f172a;
  --shadow: 0 1px 2px rgba(0,0,0,.30);
}
html, body,
.topbar, .card, .tag, .btn, .input, .footer {
  transition:
    background-color 220ms ease,
    color 220ms ease,
    border-color 220ms ease,
    box-shadow 220ms ease,
    fill 220ms ease;
}
*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  background:var(--bg);
  color:var(--fg);
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, "Noto Sans";
  line-height:1.55;
}

a{color:var(--link); text-decoration:none}
a:hover{text-decoration:underline}

.container{max-width: 980px; margin:0 auto; padding: 18px 20px}

.topbar{
  position:sticky; top:0; z-index:20;
  background: rgba(255,255,255,.85);
  backdrop-filter: blur(10px);
  border-bottom:1px solid var(--border);
}
:root[data-theme="dark"] .topbar{
  background: rgba(11,18,32,.75);
}

.topbar-inner{
  display:flex; align-items:center; justify-content:space-between; gap:16px;
}

.brand a{
  font-weight:700;
  color:var(--fg);
  letter-spacing:.2px;
}

.nav{
  display:flex; align-items:center; gap:14px; flex-wrap:wrap;
}
.nav a{
  color:var(--fg);
  opacity:.88;
  font-size:14px;
}
.nav a:hover{opacity:1}

.icon-btn{
  border:1px solid var(--border);
  background:var(--card);
  color:var(--fg);
  border-radius:10px;
  padding:8px 10px;
  cursor:pointer;
  box-shadow: var(--shadow);
}
.icon-btn:hover{filter:brightness(1.02)}

.footer{
  border-top:1px solid var(--border);
  margin-top:30px;
  background:var(--soft);
}
.footer-inner{padding: 16px 20px}

.hero{
  padding: 18px 0 6px 0;
}
.hero-title{
  font-size: 34px;
  font-weight: 750;
  letter-spacing: .2px;
}
.hero-subtitle{
  color:var(--muted);
  margin-top:4px;
}
.hero-links{
  margin-top:10px;
  display:flex; gap:14px; flex-wrap:wrap;
}
.hero-links a{
  font-size:14px;
  color:var(--link);
}

.section{
  padding: 10px 0;
}
.section-head{
  display:flex; align-items:baseline; justify-content:space-between; gap:12px;
}
.section-title{
  font-size: 18px;
  margin: 10px 0 12px 0;
  font-weight: 700;
}
.page-title{
  font-size: 24px;
  margin: 8px 0 12px 0;
  font-weight: 750;
}
.link-muted{
  font-size:14px;
  color:var(--muted);
}
.link-muted:hover{color:var(--fg)}

.prose{
  color: var(--fg);
}
.prose .muted{color:var(--muted)}

.card-list{
  display:flex;
  flex-direction:column;
  gap:12px;
}

.card{
  background:var(--card);
  border:1px solid var(--border);
  border-radius:14px;
  padding:14px 14px;
  box-shadow: var(--shadow);
}
.card-meta{
  color:var(--muted);
  font-size:13px;
}
.card-meta .dot{padding:0 6px}
.card-title{
  margin-top:6px;
  font-weight:700;
  font-size:16px;
}

.card-links a, .item-links a{
  display:inline-block;
  font-size:13px;
  padding:6px 10px;
  border:1px solid var(--border);
  background:var(--soft);
  border-radius:999px;
  color:var(--fg);
  text-decoration:none;

  transition:
    background-color 180ms ease,
    color 180ms ease,
    border-color 180ms ease,
    transform 140ms ease;
}

.card-links a:hover, .item-links a:hover{
  text-decoration:none;
  border-color: var(--link2);
  transform: translateY(-1px);
}
.card-badges{
  display:flex;
  gap:8px;
  margin:8px 0 4px 0;
}
/* Badge-style conference contribution labels (Talk / Poster) */
.badge{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  font-size:12px;
  padding:4px 10px;
  border-radius:999px;
  border:1px solid var(--border);
  background:transparent;
  color:var(--fg);
  line-height:1.2;
  white-space:nowrap;
}

.badge-talk{
  border-color: var(--link);
  color: var(--link);
}

.badge-poster{
  border-color: var(--link2);
  color: var(--link2);
}

.badge-other{
  border-color: var(--muted);
  color: var(--muted);
}

/* Small inline row helper used on homepage conference entries */
.row-inline{
  display:flex;
  align-items:center;
  gap:8px;
  flex-wrap:wrap;
}

.list{
  display:flex;
  flex-direction:column;
  gap:12px;
}
.list-item{
  padding: 10px 0;
  border-bottom:1px solid var(--border);
}
.list-item:last-child{border-bottom:0}

.grid-2{
  display:grid;
  grid-template-columns: 1fr 1fr;
  gap:18px;
}
@media (max-width: 900px){
  .grid-2{grid-template-columns:1fr}
}

.tags{
  display:flex;
  flex-wrap:wrap;
  gap:8px;
  margin-top:10px;
}
.tag{
  display:inline-block;
  font-size:13px;
  padding:6px 10px;
  border:1px solid var(--border);
  background:var(--soft);
  border-radius:999px;
  color:var(--fg);
  text-decoration:none;
}
.tag:hover{
  text-decoration:none;
  border-color: var(--link);
}

.form.card{display:flex; flex-direction:column; gap:10px}
.label{font-size:13px; color:var(--muted)}
.row{display:flex; gap:10px; align-items:center; flex-wrap:wrap}

.input{
  width:100%;
  border:1px solid var(--border);
  border-radius:12px;
  padding:10px 12px;
  background:var(--bg);
  color:var(--fg);
}

.btn{
  display:inline-block;
  border:1px solid var(--border);
  border-radius:12px;
  padding:9px 12px;
  background:var(--card);
  color:var(--fg);
  cursor:pointer;
  box-shadow: var(--shadow);
}
.btn:hover{filter:brightness(1.02)}
.btn.ghost{background:transparent; box-shadow:none}
.btn.danger{border-color:#b91c1c; color:#b91c1c}

.flash-wrap{display:flex; flex-direction:column; gap:8px; margin:12px 0}
.flash{padding:10px 12px; border-radius:12px; border:1px solid var(--border); background:var(--card)}
.flash.ok{border-color:#16a34a}
.flash.error{border-color:#b91c1c}

.muted{color:var(--muted)}
.small{font-size:14px}

.admin-actions{
  display:flex; gap:10px; flex-wrap:wrap;
}

/* Social icon row (hero) */
.social{
  margin-top:12px;
  display:flex;
  gap:10px;
  flex-wrap:wrap;
}

/* Base icon button */
.social-btn{
  width:40px;
  height:40px;
  display:inline-flex;
  align-items:center;
  justify-content:center;

  border-radius:999px;
  border:1px solid var(--border);
  background:var(--card);
  color:var(--fg);
  box-shadow: var(--shadow);

  text-decoration:none;
  transition:
    transform 140ms ease,
    background-color 180ms ease,
    color 180ms ease,
    border-color 180ms ease;
}

.social-btn i{
  font-size:18px;
  line-height:1;
}

/* Hover behaviour: background changes and icon color changes */
.social-btn:hover{
  transform: translateY(-1px);
  text-decoration:none;
}

/* Per-service hover colors */
.social-btn.github:hover{
  background:#111827;
  border-color:#111827;
  color:#ffffff;
}

.social-btn.linkedin:hover{
  background:#0a66c2;
  border-color:#0a66c2;
  color:#ffffff;
}

.social-btn.orcid:hover{
  background:#a6ce39;
  border-color:#a6ce39;
  color:#ffffff; /* readable on green */
}

.social-btn.email:hover{
  background:#ef4444;
  border-color:#ef4444;
  color:#ffffff;
}

.social-btn.scholar:hover{
  background:#2563eb;
  border-color:#2563eb;
  color:#ffffff;
}

/* Optional: slightly softer buttons in dark mode while idle */
:root[data-theme="dark"] .social-btn{
  background: var(--soft);
}