:root {
  --bg: #ffffff;
  --bg-soft: #f6f8fb;
  --text: #1f2937;
  --muted: #6b7280;
  --border: #e5e7eb;
  --accent: #1d4ed8;
  --accent-dark: #1e3a8a;

  --max-width: 1400px;
}

/* =========================
   Base
========================= */

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
}

.container {
  width: min(var(--max-width), calc(100% - 80px));
  margin: 0 auto;
}

/* =========================
   Hero
========================= */

.hero {
  padding: 42px 0 36px;
  background:
    linear-gradient(
      135deg,
      rgba(29, 78, 216, 0.06),
      rgba(255, 255, 255, 0)
    ),
    var(--bg-soft);
}

.hero-inner {
  display: flex;
  justify-content: center;
}

.hero-branding {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 60px;

  width: 100%;
  max-width: 1250px;
}

.praw-logo {
  display: block;

  width: 600px;
  max-width: 60%;
  height: auto;

  object-fit: contain;
}

.hero-event {
  min-width: 280px;
  text-align: left;
}

.edition {
  margin: 0 0 18px;

  color: var(--text);

  font-size: 1.25rem;
  font-weight: 700;
}

.wacv-row {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 10px;

  margin-bottom: 16px;
}

.wacv-row span {
  color: var(--muted);
  font-size: 0.95rem;
}

.wacv-logo {
  display: block;

  width: 190px;
  height: auto;

  object-fit: contain;
}

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

.hero-branding {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 70px;

  width: 100%;
  max-width: 1100px;
}

.workshop-date {
  width: 100%;

  margin: 28px 0 0;

  text-align: center;

  color: var(--text);
  opacity: 0.85;

  font-size: 1.2rem;
  font-weight: 600;
  line-height: 1.5;
}

/* =========================
   Navigation
========================= */

nav {
  position: sticky;
  top: 0;
  z-index: 100;

  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);

  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(8px);
}

.nav-links {
  display: flex;
  justify-content: center;
  align-items: center;

  gap: 22px;
  flex-wrap: wrap;

  min-height: 64px;
  padding: 10px 0;
}

.nav-links a {
  color: var(--text);
  text-decoration: none;

  font-size: 0.95rem;
  font-weight: 600;
}

.nav-links a:hover {
  color: var(--accent);
}

/* =========================
   Main content
========================= */

main {
  padding: 0 0 70px;
}

section {
  position: relative;

  padding: 55px 0;

  border-bottom: 1px solid var(--border);

  scroll-margin-top: 85px;
}

section:last-child {
  border-bottom: 0;
}

section h2 {
  margin: 0 0 24px;

  font-size: clamp(2rem, 4vw, 2.8rem);
  line-height: 1.15;
  letter-spacing: -0.03em;
}

section p {
  max-width: none;

  margin-top: 0;
  margin-bottom: 20px;

  font-size: 1rem;
  line-height: 1.7;
}

/* =========================
   Alternating sections
========================= */

section:nth-of-type(even)::before {
  content: "";

  position: absolute;
  inset: 0 calc(50% - 50vw);

  z-index: -1;

  background: var(--bg-soft);
}

/* =========================
   Call for Papers
========================= */

.topic-list {
  margin: 28px 0;
  padding-left: 24px;

  columns: 2;
  column-gap: 60px;
}

.topic-list li {
  margin-bottom: 12px;
  padding-right: 20px;

  line-height: 1.6;

  break-inside: avoid;
}

/* =========================
   Challenge
========================= */

#challenge h2 {
  color: var(--accent-dark);
}

/* =========================
   Info boxes
========================= */

.info-box {
  margin-top: 28px;
  padding: 22px 24px;

  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  border-radius: 8px;

  background: var(--bg-soft);
}

.info-box p {
  margin: 8px 0 0;
}

/* =========================
   Dates
========================= */

.dates-table {
  width: 100%;
  max-width: 900px;

  margin-top: 28px;

  overflow: hidden;

  border: 1px solid var(--border);
  border-radius: 10px;

  background: var(--bg);
}

.date-row {
  display: flex;
  justify-content: space-between;
  align-items: center;

  gap: 30px;

  padding: 17px 20px;

  border-bottom: 1px solid var(--border);
}

.date-row:last-child {
  border-bottom: 0;
}

.small-note {
  margin-top: 15px;

  color: var(--muted);

  font-size: 0.9rem;
}

/* =========================
   Speakers & Organizers
========================= */

.organizer-grid,
.speaker-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);

  gap: 38px 28px;

  margin-top: 34px;
}

.organizer,
.speaker {
  text-align: center;
}

.organizer-photo,
.speaker-photo {
  display: block;

  width: 180px;
  height: 180px;

  margin: 0 auto 18px;

  object-fit: cover;

  border: 1px solid var(--border);
  border-radius: 50%;
}

.organizer h3,
.speaker h3 {
  margin: 0 0 6px;

  font-size: 1.1rem;
}

.affiliation {
  margin: 0;

  color: var(--muted);

  font-size: 0.95rem;
}

.talk-title {
  max-width: 240px;

  margin: 10px auto 0;

  color: var(--accent-dark);

  font-size: 0.95rem;
  font-weight: 600;
  line-height: 1.45;
}

/* =========================
   Program Committee
========================= */

.committee-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);

  column-gap: 60px;
  row-gap: 0;

  margin-top: 30px;
}

.committee-member {
  padding: 18px 0;

  border-bottom: 1px solid var(--border);
}

.committee-member h3 {
  margin: 0 0 4px;

  font-size: 1.05rem;
}

.committee-member p {
  margin: 0;

  color: var(--muted);

  font-size: 0.95rem;
  line-height: 1.5;
}

/* =========================
   Contact
========================= */

#contact p:last-child {
  display: inline-block;

  margin-top: 8px;
  padding: 12px 16px;

  border: 1px solid var(--border);
  border-radius: 8px;

  background: var(--bg-soft);

  font-family: Consolas, "Courier New", monospace;
}

/* =========================
   Footer
========================= */

footer {
  padding: 34px 0;

  border-top: 1px solid var(--border);

  text-align: center;

  color: var(--muted);
  background: var(--bg-soft);
}

footer p {
  margin: 0;
}

/* =========================
   Tablet
========================= */

@media (max-width: 1000px) {
  .container {
    width: min(var(--max-width), calc(100% - 50px));
  }

  .hero-branding {
    gap: 40px;
  }

  .praw-logo {
    width: 520px;
    max-width: 58%;
  }

  .organizer-grid,
  .speaker-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* =========================
   Small tablet
========================= */

@media (max-width: 800px) {
  .hero-branding {
    flex-direction: column;
    gap: 28px;
  }

  .praw-logo {
    width: min(480px, 100%);
    max-width: 100%;
  }

  .hero-event {
    min-width: 0;
    text-align: center;
  }

  .wacv-row {
    align-items: center;
  }

  .nav-links {
    justify-content: flex-start;

    gap: 12px 18px;

    min-height: auto;
    padding: 14px 0;
  }

  section {
    padding: 50px 0;
  }

  .organizer-grid,
  .speaker-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .committee-grid {
    grid-template-columns: 1fr;
  }

  .topic-list {
    columns: 1;
  }
}

/* =========================
   Mobile
========================= */

@media (max-width: 520px) {
  .container {
    width: calc(100% - 28px);
  }

  .hero {
    padding: 30px 0;
  }

  .praw-logo {
    width: 100%;
  }

  .wacv-logo {
    width: 165px;
  }

  .edition {
    font-size: 1.1rem;
  }

  .nav-links a {
    font-size: 0.9rem;
  }

  section {
    padding: 42px 0;
  }

  section h2 {
    margin-bottom: 20px;
  }

  .organizer-grid,
  .speaker-grid {
    grid-template-columns: 1fr;
  }

  .organizer-photo,
  .speaker-photo {
    width: 150px;
    height: 150px;
  }

  .date-row {
    flex-direction: column;
    align-items: flex-start;

    gap: 4px;
  }
}

/* =========================
   Program / Schedule
========================= */

.program-list {
  margin-top: 28px;
  border: 1px solid var(--border);
  border-radius: 10px;
  overflow: hidden;
  max-width: 750px;
}

.program-item {
  display: grid;
  grid-template-columns: 160px 1fr;
  align-items: center;
  gap: 20px;
  padding: 16px 22px;
  border-bottom: 1px solid var(--border);
  transition: background 0.15s;
}

.program-item:last-child {
  border-bottom: none;
}

.program-item:hover {
  background: var(--bg-soft);
}

.program-time {
  color: var(--accent);
  font-size: 0.9rem;
  font-weight: 700;
  font-family: Consolas, "Courier New", monospace;
  white-space: nowrap;
}

.program-text {
  font-size: 1rem;
  color: var(--text);
  font-weight: 500;
}

/* highlight breaks differently */
.program-item.break .program-text {
  color: var(--muted);
  font-style: italic;
}

@media (max-width: 520px) {
  .program-item {
    grid-template-columns: 1fr;
    gap: 4px;
  }
}