:root {
  --bg:       #f7f6f2;
  --surface:  #ffffff;
  --border:   #e0ddd6;
  --accent:   #2d5a8e;
  --accent2:  #4a7fb5;
  --text:     #1a1a1a;
  --muted:    #6b6760;
  --break-bg: #f0ede6;
  --talk-bg:  #ffffff;
  --special-bg: #eef3f9;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  max-width: 100%;
  overflow-x: hidden;
}

body {
  font-family: 'Georgia', serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

/* ── Header ── */
header {
  background: linear-gradient(rgba(20,40,65,0.45), rgba(20,40,65,0.45)),
              url('DFKI_building.jpg') center/cover no-repeat;
  color: #fff;
  padding: 2.5rem 160px;
  text-align: center;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  min-height: 220px;
}

.header-center {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.header-logo {
  position: absolute;
  top: 0;
  bottom: 0;
  display: flex;
  align-items: center;
}

.header-logo-left  { left: 1.6rem; }
.header-logo-right { right: 1.6rem; }

.header-logo img {
  height: 80px;
  width: auto;
  object-fit: contain;
  filter: brightness(0) invert(1);
  opacity: 0.9;
}

@media (max-width: 640px) {
  header { padding: 5rem 1rem 2rem; flex-direction: column; min-height: unset; }
  .header-logo { position: static; margin-bottom: 0.5rem; }
  .header-logo img { height: 44px; }
}

header .nora {
  font-size: clamp(2.4rem, 6vw, 4rem);
  font-weight: 700;
  letter-spacing: 0.04em;
  margin-bottom: 0.35rem;
}

header .subtitle {
  font-size: clamp(1rem, 2.5vw, 1.3rem);
  font-weight: 400;
  opacity: 0.88;
  font-style: italic;
}

header .date-badge {
  display: inline-block;
  margin-top: 1.4rem;
  background: rgba(255,255,255,0.15);
  border: 1px solid rgba(255,255,255,0.35);
  border-radius: 2rem;
  padding: 0.35rem 1.1rem;
  font-size: 0.95rem;
  letter-spacing: 0.05em;
  font-family: 'Helvetica Neue', sans-serif;
}

/* ── Nav ── */
nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: center;
  gap: 0;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

nav::-webkit-scrollbar { display: none; }

nav a {
  display: inline-block;
  padding: 0.75rem 1.3rem;
  font-size: 0.82rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--muted);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: color 0.15s, border-color 0.15s;
}

nav a:hover,
nav a.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* ── Layout ── */
main {
  max-width: 820px;
  margin: 0 auto;
  padding: 3rem 1.5rem 5rem;
  display: flex;
  flex-direction: column;
  gap: 3rem;
}

/* ── Sections ── */
section h2 {
  font-size: 1.1rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--accent);
  border-bottom: 2px solid var(--accent);
  padding-bottom: 0.5rem;
  margin-bottom: 1.4rem;
}

/* ── About ── */
.abstract p {
  font-size: 1.05rem;
  color: var(--text);
  line-height: 1.75;
}

.attend-note {
  margin-top: 1.6rem;
  padding: 1.3rem 1.6rem;
  background: var(--surface);
  border: 2px solid var(--accent);
  border-radius: 8px;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  color: var(--text);
  text-align: center;
}

.attend-note .attend-heading {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
  margin-bottom: 0.4rem;
}

.attend-note p {
  font-size: 1rem;
  line-height: 1.6;
  color: var(--text);
}

.attend-note a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
  border-bottom: 1px solid var(--accent);
  transition: opacity 0.15s;
}

.attend-note a:hover { opacity: 0.7; }

/* ── Location ── */
.location-block {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.2rem 1.5rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  font-size: 1rem;
  color: var(--text);
}

.location-block .venue-name {
  font-weight: 600;
  font-size: 1.05rem;
}

.location-block .venue-detail {
  color: var(--muted);
  margin-top: 0.2rem;
  font-size: 0.95rem;
}

.location-block .venue-note {
  margin-top: 0.6rem;
  color: var(--muted);
  font-size: 0.9rem;
  font-style: italic;
}

.maps-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.2rem;
  margin-top: 1.4rem;
}

@media (max-width: 600px) {
  .maps-grid { grid-template-columns: 1fr; }
}

.map-card {
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  background: var(--surface);
}

.map-card img {
  width: 100%;
  height: auto;
  display: block;
  cursor: zoom-in;
}

.map-card .map-caption {
  padding: 0.55rem 0.8rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  font-size: 0.82rem;
  color: var(--muted);
  border-top: 1px solid var(--border);
  background: var(--break-bg);
}

/* ── Lightbox ── */
#lightbox {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.85);
  z-index: 1000;
  align-items: center;
  justify-content: center;
  cursor: zoom-out;
}

#lightbox.open { display: flex; }

#lightbox img {
  max-width: 94vw;
  max-height: 92vh;
  object-fit: contain;
  border-radius: 6px;
  box-shadow: 0 8px 40px rgba(0,0,0,0.6);
  cursor: default;
}

#lightbox-close {
  position: fixed;
  top: 1rem;
  right: 1.2rem;
  color: #fff;
  font-size: 2rem;
  line-height: 1;
  cursor: pointer;
  user-select: none;
  opacity: 0.8;
  font-family: sans-serif;
}

#lightbox-close:hover { opacity: 1; }

/* ── Schedule ── */
.schedule-wrapper {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.schedule-table {
  width: 100%;
  min-width: 480px;
  border-collapse: collapse;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  font-size: 0.95rem;
}

.schedule-table thead tr {
  border-bottom: 2px solid var(--accent);
}

.schedule-table thead th {
  text-align: left;
  padding: 0.5rem 0.75rem;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
  font-weight: 600;
}

.schedule-table tbody tr {
  border-bottom: 1px solid var(--border);
  transition: background 0.15s;
}

.schedule-table tbody tr:last-child {
  border-bottom: none;
}

.schedule-table td {
  padding: 0.75rem 0.75rem;
  vertical-align: top;
}

.col-time {
  white-space: nowrap;
  color: var(--muted);
  font-size: 0.88rem;
  width: 130px;
  padding-top: 0.85rem;
}

.col-speaker {
  width: 200px;
  font-weight: 600;
  color: var(--text);
}

.col-title { color: var(--text); }

.col-title em {
  color: var(--muted);
  font-style: italic;
}

/* row types */
tr.row-arrival td   { background: var(--break-bg); color: var(--muted); }
tr.row-break td     { background: var(--break-bg); color: var(--muted); font-style: italic; }
tr.row-lunch td     { background: var(--break-bg); color: var(--muted); font-style: italic; }
tr.row-special td   { background: var(--special-bg); }
tr.row-tba .col-title em { color: #b0aca5; }

/* ── Collapsible abstracts ── */
.has-abstract { cursor: pointer; }

.has-abstract::after {
  content: ' ▸';
  font-size: 0.7em;
  color: var(--accent);
}

.has-abstract.open::after { content: ' ▾'; }

.has-abstract:hover { color: var(--accent); }

.abstract-row { display: none; }
.abstract-row.open { display: table-row; }

.abstract-row td {
  padding: 0 0.75rem 0.9rem;
  background: var(--surface);
}

.abstract-row .abstract-inner {
  padding: 0.8rem 1rem;
  background: var(--break-bg);
  border-left: 3px solid var(--accent);
  border-radius: 0 4px 4px 0;
  font-size: 0.88rem;
  line-height: 1.65;
  color: var(--muted);
}

.abstract-row .abstract-inner p + p { margin-top: 0.6rem; }

/* ── Organizers ── */
.organizers-grid {
  display: flex;
  gap: 1.2rem;
  flex-wrap: wrap;
}

.organizer-card {
  flex: 1;
  min-width: 180px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1rem 1.2rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
}

.organizer-card .org-name {
  font-weight: 600;
  font-size: 1rem;
  color: var(--text);
}

.organizer-card .org-affiliation {
  font-size: 0.85rem;
  color: var(--muted);
  margin-top: 0.2rem;
}

.organizer-card .org-email {
  font-size: 0.85rem;
  margin-top: 0.5rem;
}

.organizer-card .org-email a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.15s;
}

.organizer-card .org-email a:hover { border-color: var(--accent); }

/* ── Funding ── */
.funding {
  border-top: 1px solid var(--border);
  padding: 2.5rem 1.5rem;
  text-align: center;
  font-family: 'Helvetica Neue', Arial, sans-serif;
}

.funding .funding-label {
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--muted);
  margin-bottom: 1.4rem;
}

.funding-logos {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 3rem;
  flex-wrap: wrap;
}

.funding-logos img {
  height: 70px;
  width: auto;
  object-fit: contain;
  opacity: 0.85;
  transition: opacity 0.2s;
}

.funding-logos img:hover { opacity: 1; }

/* ── Footer ── */
footer {
  text-align: center;
  padding: 1.2rem 1rem 2rem;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  font-size: 0.85rem;
  color: var(--muted);
  border-top: 1px solid var(--border);
}

footer a {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid var(--border);
}

footer a:hover { color: var(--accent); border-color: var(--accent); }