/* ============================
   General & Typography
   ============================ */
:root {
  --primary-color: #1e3a5f;
  --accent-color: #2b77b4;
  --accent-light: #4a9fd4;
  --light-bg: #f4f7fb;
  --dark-bg: #1e3a5f;
  --text-color: #333;
  --heading-font: "Raleway", sans-serif;
  --body-font: "Roboto", sans-serif;
}

body {
  font-family: var(--body-font);
  color: var(--text-color);
  background: #fff;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--heading-font);
}

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

a:hover {
  color: #1a5a8a;
}

ul {
  padding-left: 1.4rem;
}

ul li {
  margin-bottom: 0.5rem;
  line-height: 1.7;
}

/* ============================
   Header / Navigation
   ============================ */
.header {
  background: rgba(30, 58, 95, 0.97);
  padding: 12px 0;
  z-index: 997;
  box-shadow: 0 2px 12px rgba(0,0,0,0.25);
  transition: all 0.3s;
}

.header .sitename {
  font-size: 1.4rem;
  font-weight: 800;
  color: #fff;
  letter-spacing: 0.5px;
  margin: 0;
}

.header .sitename span {
  color: var(--accent-light);
}

.navmenu ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 2px;
}

.navmenu ul li a {
  color: #c8d8ea;
  font-family: var(--heading-font);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.4px;
  padding: 7px 11px;
  border-radius: 4px;
  transition: all 0.25s;
  text-transform: uppercase;
}

.navmenu ul li a:hover,
.navmenu ul li a.active {
  color: #fff;
  background: var(--accent-color);
}

/* Mobile nav toggle */
.mobile-nav-toggle {
  color: #fff;
  font-size: 1.5rem;
  cursor: pointer;
  display: none;
}

@media (max-width: 1199px) {
  .mobile-nav-toggle {
    display: block;
  }

  .navmenu ul {
    display: none;
    flex-direction: column;
    position: fixed;
    top: 60px;
    right: 0;
    bottom: 0;
    width: 260px;
    background: var(--primary-color);
    padding: 20px;
    overflow-y: auto;
    z-index: 998;
  }

  .navmenu.mobile-nav-active ul {
    display: flex;
  }
}

/* ============================
   Hero Section
   ============================ */
.hero {
  min-height: 60vh;
  background: var(--dark-bg);
  display: flex;
  flex-direction: column;
  justify-content: center;
  position: relative;
  overflow: hidden;
  padding-top: 70px;
  padding-bottom: 60px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(to bottom, rgba(15,30,60,0.96) 0%, rgba(15,30,60,0.96) 100%),
    url('../img/hero-bg.jpg') center center / cover no-repeat;
  z-index: 0;
}

.hero .container {
  position: relative;
  z-index: 2;
  padding: 80px 20px 40px;
}

section.hero h2,
section.hero h2::after {
  color: #ffffff !important;
  background: none;
  font-size: 2.1rem;
  font-weight: 800;
  line-height: 1.35;
  max-width: 860px;
  text-shadow: 0 2px 16px rgba(0,0,0,0.9);
}

section.hero p {
  color: #e0ecf8 !important;
  font-size: 1.1rem;
  margin-top: 12px;
  font-weight: 500;
  text-shadow: 0 1px 8px rgba(0,0,0,0.8);
}

section.hero p.hero-tagline {
  font-size: 1.2rem;
  font-weight: 600;
  letter-spacing: 0.3px;
  margin-top: 16px;
}

section.hero p.hero-venue {
  font-size: 1rem;
  font-weight: 400;
  color: #c3d8ee !important;
  margin-top: 8px;
}

.about-info {
  position: relative;
  z-index: 2;
  background: #fff;
  border-top: 4px solid var(--accent-color);
  padding: 48px 0;
}

.about-info h2 {
  color: var(--primary-color);
  font-size: 1.55rem;
  font-weight: 700;
  margin-bottom: 16px;
  position: relative;
  padding-bottom: 10px;
}

.about-info h2::after {
  content: '';
  display: block;
  width: 44px;
  height: 3px;
  background: var(--accent-color);
  margin-top: 8px;
}

.about-info p {
  color: #444;
  line-height: 1.85;
  font-size: 0.96rem;
}

.about-info h3 {
  color: var(--accent-color);
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.2px;
  margin-bottom: 6px;
}

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

/* ============================
   Sections (general)
   ============================ */
.section {
  padding: 70px 0;
}

.section.light-background {
  background: var(--light-bg);
}

.section-title {
  margin-bottom: 30px;
}

.section-title h2,
.section h2 {
  font-size: 1.9rem;
  font-weight: 800;
  color: var(--primary-color);
  position: relative;
  padding-bottom: 12px;
  margin-bottom: 24px;
}

.section-title h2::after,
.section h2::after {
  content: '';
  display: block;
  width: 44px;
  height: 3px;
  background: var(--accent-color);
  margin-top: 8px;
}

.section p,
.section ul li {
  font-size: 0.96rem;
  line-height: 1.85;
  color: #444;
}

/* ============================
   Call for Papers: track headings
   ============================ */
.track-heading {
  margin-top: 34px;
  margin-bottom: 12px;
  font-family: var(--heading-font);
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--primary-color);
  padding-left: 12px;
  border-left: 4px solid var(--accent-color);
}

/* ============================
   Program / Schedule
   ============================ */
.program-table {
  width: 100%;
  margin-top: 20px;
  background: #fff;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 12px rgba(30, 58, 95, 0.07);
}

.program-table td {
  padding: 14px 18px;
  border-top: 1px solid #eef2f7;
  vertical-align: top;
}

.program-table tr:first-child td {
  border-top: none;
}

.prog-time {
  width: 88px;
  font-family: var(--heading-font);
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--accent-color);
  white-space: nowrap;
}

.prog-title {
  display: block;
  font-family: var(--heading-font);
  font-weight: 700;
  font-size: 1rem;
  color: var(--primary-color);
}

.prog-detail {
  display: block;
  margin-top: 3px;
  font-size: 0.9rem;
  line-height: 1.6;
  color: #5a6b7d;
}

.program-table tr.prog-break {
  background: #f7fafd;
}

.program-table tr.prog-break .prog-title {
  font-weight: 600;
  color: #5a6b7d;
}

.tba {
  display: inline-block;
  margin-left: 8px;
  padding: 1px 8px;
  border-radius: 10px;
  background: #eef3f9;
  color: #6b7f93;
  font-family: var(--body-font);
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  vertical-align: 2px;
}

/* ============================
   Important Dates
   ============================ */
.dates-list {
  list-style: none;
  padding: 0;
}

.dates-list li {
  padding: 10px 16px;
  border-left: 4px solid var(--accent-color);
  margin-bottom: 12px;
  background: #fff;
  border-radius: 0 6px 6px 0;
  box-shadow: 0 1px 6px rgba(0,0,0,0.06);
  font-size: 0.96rem;
}

.date-label {
  font-weight: 700;
  color: var(--primary-color);
  margin-right: 8px;
}

.date-note {
  display: inline-block;
  margin-left: 8px;
  padding: 1px 8px;
  border-radius: 10px;
  background: #eef3f9;
  color: #6b7f93;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  vertical-align: 1px;
}

.date-note.date-fixed {
  background: var(--accent-color);
  color: #fff;
}

/* ============================
   Organizers / Speakers
   ============================ */
.speakers.section {
  padding: 70px 0;
  background: #fff;
}

.speakers .section-title h2 {
  font-size: 1.9rem;
  font-weight: 800;
  color: var(--primary-color);
}

.member {
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 14px rgba(0,0,0,0.09);
  background: #fff;
  border: 1px solid #e4ecf4;
  transition: transform 0.25s, box-shadow 0.25s;
}

.member:hover {
  transform: translateY(-4px);
  box-shadow: 0 6px 24px rgba(43,119,180,0.15);
}

.member img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  display: block;
}

.member-info {
  padding: 16px;
}

.member-info-content h4 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--primary-color);
  margin-bottom: 4px;
}

.member-info-content h4 a {
  color: var(--primary-color);
}

.member-info-content h4 a:hover {
  color: var(--accent-color);
}

.pc-note {
  text-align: center;
  color: #6b7f93;
  font-size: 0.92rem;
}

.member-info-content span {
  font-size: 0.82rem;
  color: #666;
  display: block;
  margin-bottom: 3px;
}

.member-info .social {
  display: flex;
  gap: 8px;
  margin-top: 8px;
}

.member-info .social a {
  width: 30px;
  height: 30px;
  border-radius: 50%;
  border: 1px solid #c8d8ea;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-color);
  font-size: 0.85rem;
  transition: all 0.25s;
}

.member-info .social a:hover {
  background: var(--accent-color);
  border-color: var(--accent-color);
  color: #fff;
}

/* ============================
   Submit button
   ============================ */
.btn-submit {
  display: inline-block;
  background: var(--accent-color);
  color: #fff;
  padding: 12px 32px;
  border-radius: 4px;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.25s;
}

.btn-submit:hover {
  background: #1f5c8f;
  color: #fff;
}

/* ============================
   Footer
   ============================ */
.footer {
  background: var(--dark-bg);
  padding: 24px 0;
}

.footer .copyright {
  color: #8aafcc;
  font-size: 0.85rem;
}

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

/* ============================
   Scroll Top
   ============================ */
.scroll-top {
  position: fixed;
  right: 20px;
  bottom: 20px;
  width: 40px;
  height: 40px;
  background: var(--accent-color);
  color: #fff;
  border-radius: 50%;
  font-size: 1.4rem;
  opacity: 0;
  visibility: hidden;
  transition: all 0.4s;
  z-index: 99;
}

.scroll-top.active {
  opacity: 1;
  visibility: visible;
}

.scroll-top:hover {
  background: #1a5a8a;
  color: #fff;
}

/* ============================
   Responsive
   ============================ */
@media (max-width: 768px) {
  .hero h2 {
    font-size: 1.5rem;
  }

  .about-info h2 {
    font-size: 1.3rem;
  }
}