/* ===== Base & Variables ===== */
:root {
  --primary: #60a5fa;
  --primary-light: #93c5fd;
  --accent: #00a8e8;
  --accent-dark: #38bdf8;
  --gold: #d4a843;
  --text: #e2e8f0;
  --text-light: #94a3b8;
  --bg: #0f172a;
  --bg-light: #1e293b;
  --bg-card: #1e293b;
  --bg-card-alt: #253349;
  --bg-dark: #020617;
  --border: #334155;
  --shadow: 0 2px 15px rgba(0, 0, 0, 0.3);
  --radius: 8px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Segoe UI', 'Roboto', 'Helvetica Neue', Arial, sans-serif;
  color: var(--text);
  line-height: 1.7;
  font-size: 16px;
  background: var(--bg);
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.3s;
}

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

img {
  max-width: 100%;
  height: auto;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ===== Navigation ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(15, 23, 42, 0.95);
  backdrop-filter: blur(10px);
  padding: 0 0;
  transition: box-shadow 0.3s;
  box-shadow: 0 1px 0 var(--border);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-brand {
  color: #fff;
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: 1px;
}

.nav-brand span {
  color: var(--accent);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: #fff;
  margin: 5px 0;
  transition: 0.3s;
}

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

.nav-links a {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.9rem;
  padding: 8px 14px;
  border-radius: 4px;
  transition: all 0.3s;
  font-weight: 500;
}

.nav-links a:hover,
.nav-links a.active {
  color: #fff;
  background: rgba(0, 168, 232, 0.15);
}

/* ===== Hero Section ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, rgba(2, 6, 23, 0.92), rgba(15, 23, 42, 0.88)),
              url('../images/abu-dhabi-banner.jpg') center/cover no-repeat;
  color: #fff;
  text-align: center;
  padding: 120px 20px 80px;
}

.hero-content {
  max-width: 900px;
}

.hero-logos {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 30px;
  margin-bottom: 30px;
  flex-wrap: wrap;
}

.hero-logos img {
  height: 60px;
  opacity: 0.95;
}

.hero h1 {
  font-size: 3rem;
  font-weight: 800;
  margin-bottom: 8px;
  letter-spacing: 3px;
  text-transform: uppercase;
}

.hero h1 .highlight {
  color: var(--accent);
}

.hero .subtitle {
  font-size: 1.25rem;
  font-weight: 300;
  margin-bottom: 25px;
  color: rgba(255, 255, 255, 0.85);
  line-height: 1.5;
}

.hero .venue-info {
  display: inline-flex;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
  justify-content: center;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 50px;
  padding: 14px 32px;
  margin-top: 10px;
  font-size: 1.05rem;
}

.hero .venue-info .divider {
  width: 1px;
  height: 20px;
  background: rgba(255, 255, 255, 0.2);
}

.hero .badge {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  padding: 6px 20px;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 20px;
  letter-spacing: 1px;
  text-transform: uppercase;
}

/* ===== Section Common ===== */
section {
  padding: 80px 0;
  background: var(--bg);
}

section:nth-child(even) {
  background: var(--bg-light);
}

.section-title {
  text-align: center;
  margin-bottom: 50px;
}

.section-title h2 {
  font-size: 2rem;
  color: #fff;
  margin-bottom: 10px;
  font-weight: 700;
}

.section-title p {
  color: var(--text-light);
  font-size: 1.05rem;
}

.section-title .underline {
  display: block;
  width: 60px;
  height: 3px;
  background: var(--accent);
  margin: 12px auto 0;
  border-radius: 2px;
}

/* ===== About Section ===== */
.about-content {
  max-width: 850px;
  margin: 0 auto;
  font-size: 1.05rem;
  color: var(--text);
}

.about-content p {
  margin-bottom: 18px;
  text-align: justify;
}

/* ===== Topics Section ===== */
.topics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
  max-width: 950px;
  margin: 0 auto;
}

.topic-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
  border-left: 4px solid var(--accent);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  transition: transform 0.3s, box-shadow 0.3s;
}

.topic-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.4);
  border-color: var(--accent);
}

.topic-card h3 {
  color: var(--primary);
  font-size: 1.05rem;
  margin-bottom: 8px;
}

.topic-card p {
  color: var(--text-light);
  font-size: 0.92rem;
  line-height: 1.6;
}

/* ===== Important Dates ===== */
.dates-timeline {
  max-width: 650px;
  margin: 0 auto;
  position: relative;
}

.dates-timeline::before {
  content: '';
  position: absolute;
  left: 18px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--accent);
  opacity: 0.2;
}

.date-item {
  display: flex;
  align-items: flex-start;
  gap: 24px;
  margin-bottom: 28px;
  position: relative;
}

.date-dot {
  width: 38px;
  height: 38px;
  min-width: 38px;
  border-radius: 50%;
  background: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 700;
  font-size: 0.75rem;
  z-index: 1;
}

.date-content h3 {
  font-size: 1rem;
  color: #fff;
  margin-bottom: 2px;
}

.date-content p {
  color: var(--accent);
  font-weight: 600;
  font-size: 0.95rem;
}

.date-content .tbd {
  color: var(--text-light);
  font-style: italic;
  font-weight: 400;
}

/* ===== Schedule / Program ===== */
.schedule-table {
  max-width: 800px;
  margin: 0 auto;
  border-collapse: collapse;
  width: 100%;
  background: var(--bg-card);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.schedule-table thead {
  background: rgba(0, 168, 232, 0.15);
  color: #fff;
}

.schedule-table th {
  padding: 14px 20px;
  text-align: left;
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--accent);
}

.schedule-table td {
  padding: 12px 20px;
  border-bottom: 1px solid var(--border);
  font-size: 0.95rem;
  color: var(--text);
}

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

.schedule-table .session-header {
  background: var(--bg-card-alt);
  font-weight: 700;
  color: var(--primary);
}

.schedule-table .break-row {
  background: rgba(212, 168, 67, 0.08);
  font-style: italic;
  color: var(--text-light);
}

/* ===== Speakers / Keynotes ===== */
.speakers-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 36px;
  max-width: 700px;
  margin: 0 auto;
}

.speaker-card {
  text-align: center;
}

.speaker-card .speaker-photo {
  width: 150px;
  height: 150px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--bg-card-alt), #334155);
  margin: 0 auto 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 2.5rem;
  font-weight: 700;
  overflow: hidden;
  border: 3px solid var(--border);
}

.speaker-card .speaker-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.speaker-card h3 {
  color: #fff;
  font-size: 1.1rem;
  margin-bottom: 4px;
}

.speaker-card .speaker-role {
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 4px;
}

.speaker-card .speaker-affiliation {
  color: var(--text-light);
  font-size: 0.88rem;
}

/* ===== Organizers ===== */
.organizers-section h3 {
  text-align: center;
  color: var(--primary);
  margin: 40px 0 24px;
  font-size: 1.3rem;
}

.organizers-section h3:first-of-type {
  margin-top: 0;
}

.organizers-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 28px;
  max-width: 850px;
  margin: 0 auto;
}

.organizer-card {
  text-align: center;
  padding: 20px;
}

.organizer-card .organizer-photo {
  width: 110px;
  height: 110px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--bg-card-alt), #334155);
  margin: 0 auto 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-light);
  font-size: 1.8rem;
  font-weight: 700;
  overflow: hidden;
  border: 2px solid var(--border);
}

.organizer-card .organizer-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.organizer-card h4 {
  color: #fff;
  font-size: 1rem;
  margin-bottom: 4px;
}

.organizer-card p {
  color: var(--text-light);
  font-size: 0.85rem;
}

/* ===== Call for Papers ===== */
.cfp-box {
  max-width: 800px;
  margin: 0 auto;
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 40px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  border-top: 4px solid var(--accent);
}

.cfp-box h3 {
  color: var(--primary);
  margin-bottom: 12px;
  font-size: 1.2rem;
}

.cfp-box p {
  margin-bottom: 16px;
  color: var(--text);
}

.cfp-box ul {
  margin-left: 20px;
  margin-bottom: 20px;
}

.cfp-box ul li {
  margin-bottom: 8px;
  color: var(--text);
  line-height: 1.6;
}

.btn {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  padding: 12px 30px;
  border-radius: 30px;
  font-weight: 600;
  font-size: 0.95rem;
  transition: all 0.3s;
  border: none;
  cursor: pointer;
}

.btn:hover {
  background: var(--accent-dark);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 4px 20px rgba(0, 168, 232, 0.25);
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--accent);
  color: var(--accent);
}

.btn-outline:hover {
  background: var(--accent);
  color: #fff;
}

/* ===== SENSAR Network ===== */
.sensar-banner {
  background: linear-gradient(135deg, #0c1a33, #132744);
  color: #fff;
  padding: 50px 0;
  text-align: center;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.sensar-banner h2 {
  font-size: 1.6rem;
  margin-bottom: 12px;
}

.sensar-banner p {
  max-width: 700px;
  margin: 0 auto;
  font-size: 1.02rem;
  color: rgba(255, 255, 255, 0.75);
  line-height: 1.7;
}

/* ===== Footer ===== */
.footer {
  background: var(--bg-dark);
  color: rgba(255, 255, 255, 0.5);
  padding: 40px 0 24px;
  text-align: center;
  border-top: 1px solid var(--border);
}

.footer-logos {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 30px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}

.footer-logos img {
  height: 40px;
  opacity: 0.7;
}

.footer p {
  font-size: 0.88rem;
  margin-bottom: 6px;
}

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

.footer .footer-links {
  margin-top: 12px;
}

.footer .footer-links a {
  margin: 0 12px;
  font-size: 0.88rem;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .hero h1 {
    font-size: 2rem;
    letter-spacing: 1px;
  }

  .hero .subtitle {
    font-size: 1.05rem;
  }

  .hero .venue-info {
    flex-direction: column;
    gap: 8px;
    padding: 12px 20px;
    border-radius: 12px;
  }

  .hero .venue-info .divider {
    display: none;
  }

  section {
    padding: 50px 0;
  }

  .section-title h2 {
    font-size: 1.6rem;
  }

  .nav-toggle {
    display: block;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--bg);
    flex-direction: column;
    padding: 16px;
    gap: 4px;
    border-bottom: 1px solid var(--border);
  }

  .nav-links.active {
    display: flex;
  }

  .nav-links a {
    padding: 10px 16px;
  }

  .hero-logos img {
    height: 45px;
  }

  .schedule-table th,
  .schedule-table td {
    padding: 10px 12px;
    font-size: 0.85rem;
  }

  .cfp-box {
    padding: 24px;
  }

  .speakers-grid {
    grid-template-columns: 1fr 1fr;
    gap: 20px;
  }

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

@media (max-width: 480px) {
  .hero h1 {
    font-size: 1.6rem;
  }

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

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