@import url("https://fonts.googleapis.com/css2?family=Poppins:wght@300;400;500;600;700;800&display=swap");

:root {
  --primary-blue: #0a3d62;
  --secondary-blue: #1e88e5;
  --accent-orange: #ffab40;
  --light-bg: #f7f9fc;
  --white: #ffffff;
  --dark-text: #333;
  --light-text: #6c757d;
  --border-color: #e9ecef;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.09);
  --header-height: 80px;
}

/* --- General Styles --- */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height);
}
body {
  font-family: "Poppins", sans-serif;
  color: var(--light-text);
  background-color: var(--white);
  line-height: 1.7;
  font-size: 16px;
}
.no-scroll {
  overflow: hidden;
}
.container {
  width: 90%;
  max-width: 1200px;
  margin: auto;
}
h1,
h2,
h3,
h4 {
  font-weight: 700;
  color: var(--primary-blue);
  margin-bottom: 1rem;
}
section {
  padding: 100px 0;
  overflow: hidden;
}
.about-conference-section,
.speakers-section,
.committee-section {
  background-color: var(--white);
}
.dates-section,
.about-aec-section {
  background-color: var(--light-bg);
}
.section-title {
  text-align: center;
  font-size: 2.8rem;
  margin-bottom: 60px;
}
.section-title .bengali {
  color: var(--secondary-blue);
  display: block;
  font-size: 0.7em;
}
.bengali {
  font-weight: 400;
}
.btn {
  text-decoration: none;
  font-weight: 600;
  transition: all 0.4s ease;
  display: inline-block;
  padding: 12px 30px;
  border-radius: 50px;
  border: 2px solid transparent;
}
.btn.primary {
  background: linear-gradient(90deg, var(--accent-orange), #ff9800);
  color: var(--white);
  box-shadow: 0 5px 15px rgba(255, 171, 64, 0.4);
}
.btn.primary:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 20px rgba(255, 171, 64, 0.5);
}
.btn.secondary {
  background-color: transparent;
  color: var(--white);
  border-color: var(--accent-orange);
}
.btn.secondary:hover {
  background-color: var(--accent-orange);
  color: var(--primary-blue);
}
.fade-in {
  opacity: 0;
  transform: translateY(50px);
  transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* --- Header --- */
.header {
  background-color: var(--white);
  box-shadow: 0 2px 15px rgba(0, 0, 0, 0.08);
  position: fixed;
  width: 100%;
  top: 0;
  left: 0;
  z-index: 1000;
  height: var(--header-height);
}

.navbar {
  display: flex;
  align-items: center;
  height: 100%;
  gap: 15px; /* Adds a small space between items */
}

/* New styles for the added logos */
.header-logos {
  display: flex;
  align-items: center;
  gap: 15px;
}
.logo-img {
  height: 45px;
  width: auto;
}

.logo-text {
  color: var(--primary-blue);
  border: 2px solid var(--primary-blue);
  padding: 5px 10px;
  text-align: center;
  line-height: 1.1;
}

.logo-text span:first-child {
  font-size: 1.3rem;
  font-weight: 800;
  letter-spacing: 1px;
}
.logo-text span:last-child {
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0;
  border-top: 1px solid var(--primary-blue);
  text-transform: uppercase;
}

/* This is the key fix for the layout */
.nav-menu {
  margin-left: auto; /* Pushes links and buttons to the right */
}

.nav-links {
  list-style: none;
  display: flex;
  align-items: center; /* Vertically align links */
  margin: 0;
  padding: 0;
}
.nav-links li {
  margin: 0 15px;
}
.nav-links a {
  text-decoration: none;
  color: var(--dark-text);
  font-weight: 500;
  font-size: 0.9rem;
  transition: color 0.3s;
  padding: 5px;
  white-space: nowrap; /* Prevent links from wrapping */
}
.nav-links a:hover {
  color: var(--secondary-blue);
}
.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}
.header-actions .register-btn,
.header-actions .paper-btn {
  text-decoration: none;
  font-weight: 500;
  padding: 8px 18px;
  border-radius: 8px;
  transition: all 0.3s;
  white-space: nowrap;
}
.header-actions .register-btn {
  background-color: var(--secondary-blue);
  color: var(--white);
}
.header-actions .register-btn:hover {
  background-color: var(--primary-blue);
}
.header-actions .paper-btn {
  background-color: transparent;
  color: var(--primary-blue);
  border: 2px solid var(--secondary-blue);
}
.header-actions .paper-btn:hover {
  background-color: var(--secondary-blue);
  color: var(--white);
}
.mobile-nav-toggle {
  display: none;
  cursor: pointer;
  font-size: 24px;
  color: var(--primary-blue);
}
.mobile-reg-btn,
.mobile-paper-btn {
  display: none;
}

/* --- Hero Section --- */
.hero {
  color: var(--white);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  position: relative;
  padding-top: var(--header-height);
  padding-bottom: 20px;
}
.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(
    135deg,
    rgba(10, 61, 98, 0.92) 0%,
    rgba(30, 136, 229, 0.85) 100%
  );
}
#particles-js {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
}
.hero-content {
  position: relative;
  z-index: 2;
  width: 100%;
}
.hero-top-text {
  color: var(--accent-orange);
  font-weight: 500;
  margin-bottom: 20px;
}
.hero h1 {
  font-size: 4rem;
  color: var(--white);
  font-weight: 800;
}
.hero .vaani {
  font-size: 5rem;
  color: var(--accent-orange);
  font-weight: 800;
  line-height: 1;
  margin-top: -10px;
}
.hero .subtitle {
  font-size: 1.3rem;
  margin-top: 20px;
  font-weight: 300;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}
.hero-info {
  display: flex;
  justify-content: center;
  gap: 30px;
  margin: 30px 0 40px;
  flex-wrap: wrap;
}
.hero-info i {
  color: var(--accent-orange);
  margin-right: 8px;
}
.btn-group {
  display: flex;
  justify-content: center;
  gap: 20px;
  flex-wrap: wrap;
}

/* --- About & AEC Sections --- */
.about-conference-section,
.about-aec-section {
  background-color: var(--white);
}
.conference-details-grid,
.about-aec-container {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 50px;
  align-items: center;
}
.conference-image img,
.about-aec-image img {
  width: 100%;
  border-radius: 10px;
  box-shadow: var(--shadow);
}
.partner-logos {
  margin-bottom: 20px;
}
.partner-logos img {
  height: 50px;
  margin-right: 20px;
  opacity: 0.8;
}
.bengali-block {
  margin-top: 20px;
  padding: 15px;
  background: var(--light-bg);
  border-left: 3px solid var(--secondary-blue);
  border-radius: 5px;
}

/* --- Speakers Section --- */
.speakers-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 30px;
}
.speaker-card {
  background: var(--white);
  border-radius: 10px;
  box-shadow: var(--shadow);
  text-align: center;
  overflow: hidden;
  transition: transform 0.4s ease, box-shadow 0.4s ease;
}
.speaker-card:hover {
  transform: translateY(-10px);
}
.speaker-img {
  width: 100%;
  height: 280px;
  overflow: hidden;
}
.speaker-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top;
}
.speaker-info {
  padding: 25px 15px;
}
.speaker-info h4 {
  font-size: 1.2rem;
}
.speaker-info p {
  font-size: 0.95rem;
  color: var(--light-text);
}

/* --- Important Dates Section --- */
.dates-section {
  background-color: var(--light-bg);
}
.timeline {
  position: relative;
  max-width: 800px;
  margin: 0 auto;
}
.timeline::before {
  content: "";
  position: absolute;
  width: 3px;
  background-color: var(--border-color);
  top: 0;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
}
.timeline-item {
  position: relative;
  width: 50%;
  padding: 20px 40px;
  --accent-color: var(--secondary-blue);
}
.timeline-item:nth-child(1) {
  --accent-color: #29b6f6;
}
.timeline-item:nth-child(2) {
  --accent-color: #66bb6a;
}
.timeline-item:nth-child(3) {
  --accent-color: #ffa726;
}
.timeline-item:nth-child(4) {
  --accent-color: #ef5350;
}
.timeline-item:nth-child(5) {
  --accent-color: #ab47bc;
}
.timeline-item:nth-child(odd) {
  left: 0;
}
.timeline-item:nth-child(even) {
  left: 50%;
}
.timeline-dot {
  content: "";
  position: absolute;
  width: 20px;
  height: 20px;
  background-color: var(--white);
  border: 4px solid var(--accent-color);
  border-radius: 50%;
  top: 35px;
  z-index: 1;
  transition: transform 0.3s;
}
.timeline-item:hover .timeline-dot {
  transform: scale(1.2);
}
.timeline-item:nth-child(odd) .timeline-dot {
  right: -11.5px;
}
.timeline-item:nth-child(even) .timeline-dot {
  left: -8.5px;
}
.timeline-content {
  background: var(--white);
  padding: 30px;
  border-radius: 10px;
  box-shadow: 0 5px 25px rgba(0, 0, 0, 0.07);
  transition: transform 0.3s;
  border-left: 4px solid var(--accent-color);
}
.timeline-item:hover .timeline-content {
  transform: translateY(-5px);
}
.timeline-content h3 {
  font-size: 1.2rem;
  color: var(--accent-color);
}
.timeline-content p {
  font-size: 1.1rem;
  font-weight: 500;
  color: var(--dark-text);
}
.timeline-item:nth-child(odd) .timeline-content {
  text-align: right;
  border-left: none;
  border-right: 4px solid var(--accent-color);
}

/* --- Committee Section --- */
.committee-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}
.committee-column {
  display: flex;
  flex-direction: column;
  gap: 30px;
}
.committee-group {
  background: var(--light-bg);
  padding: 30px;
  border-radius: 10px;
  border-left: 4px solid var(--secondary-blue);
  transition: all 0.3s ease;
}
.committee-group:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow);
}
.committee-group h3 {
  color: var(--primary-blue);
  border-bottom: 2px solid var(--border-color);
  padding-bottom: 10px;
  display: flex;
  align-items: center;
}
.committee-group h3 i {
  color: var(--accent-orange);
  margin-right: 15px;
  font-size: 1.2rem;
}
.committee-group h3 .bengali {
  font-size: 0.9em;
  color: var(--secondary-blue);
  margin-left: auto;
}
.committee-group ul {
  list-style: none;
  padding: 10px 0 0 0;
}
.committee-group li {
  padding: 8px 0;
  border-bottom: 1px dashed var(--border-color);
  font-size: 1rem;
  color: var(--dark-text);
}
.committee-group li:last-child {
  border-bottom: none;
}
.committee-group li .bengali {
  color: var(--light-text);
  display: block;
  font-size: 0.9rem;
}

/* --- Footer --- */
.footer {
  background: var(--primary-blue);
  color: #e0e0e0;
  padding-top: 80px;
}
.footer-container {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 50px;
  padding-bottom: 50px;
}
.footer .logo {
  margin-bottom: 20px;
}
.footer .logo .logo-text {
  color: var(--white);
  border-color: var(--white);
}
.footer .logo .logo-text span:last-child {
  border-color: var(--white);
}
.footer h4 {
  color: var(--accent-orange);
}
.footer a {
  color: #e0e0e0;
  text-decoration: none;
  transition: color 0.3s;
}
.footer a:hover {
  color: var(--white);
}
.footer-links ul {
  list-style: none;
  padding: 0;
}
.footer-links li {
  margin-bottom: 12px;
}
.footer-contact p {
  display: flex;
  align-items: center;
}
.footer-contact i {
  margin-right: 10px;
  color: var(--accent-orange);
}
.footer-bottom {
  text-align: center;
  padding: 25px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

/* --- Responsive Design --- */
@media (max-width: 1200px) {
  /* Reduce gap on slightly smaller screens to prevent early wrapping */
  .nav-links li {
    margin: 0 10px;
  }
}

@media (max-width: 992px) {
  html {
    scroll-padding-top: 100px; /* Adjust scroll padding for mobile header */
  }
  .header {
    height: auto; /* Allow header to grow in height for stacked items */
  }
  .navbar {
    flex-wrap: wrap; /* Allow items to wrap to the next line */
    padding-top: 10px;
    padding-bottom: 10px;
  }
  .header-logos {
    order: 1; /* Logos on top */
    width: 100%;
    justify-content: center;
    margin-bottom: 10px;
  }
  .logo {
    order: 2; /* Conference title second */
  }
  .nav-menu {
    margin-left: 0; /* Reset margin */
  }
  .mobile-nav-toggle {
    display: block;
    order: 3; /* Hamburger icon third */
    margin-left: auto; /* Push to the far right */
    z-index: 1001;
  }

  /* Your original full-screen menu logic is preserved */
  .header-actions {
    display: none;
  }
  .nav-menu {
    position: fixed;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100vh;
    background-color: var(--white);
    flex-direction: column;
    justify-content: center;
    align-items: center;
    transition: left 0.4s ease-in-out;
    order: 4;
  }
  .nav-menu.active {
    left: 0;
  }
  .nav-links {
    flex-direction: column;
    text-align: center;
  }
  .nav-links li {
    margin: 15px 0;
    font-size: 1.2rem;
  }
  .mobile-reg-btn,
  .mobile-paper-btn {
    display: block;
    margin-top: 10px;
  }
  .mobile-reg-btn .register-btn,
  .mobile-paper-btn .paper-btn {
    text-decoration: none;
    font-weight: 500;
    padding: 10px 25px;
    border-radius: 50px;
  }
  .mobile-reg-btn .register-btn {
    background-color: var(--secondary-blue);
    color: var(--white);
  }
  .mobile-paper-btn .paper-btn {
    background-color: transparent;
    color: var(--primary-blue);
    border: 1px solid var(--secondary-blue);
  }
  .conference-details-grid,
  .about-aec-container,
  .committee-grid {
    grid-template-columns: 1fr;
  }
  .conference-image,
  .about-aec-image {
    order: -1;
    margin-bottom: 30px;
  }
  .footer-container {
    grid-template-columns: 1fr;
    text-align: center;
  }
}
@media (max-width: 768px) {
  .hero {
    min-height: 100vh;
  }
  .hero h1 {
    font-size: 2.5rem;
  }
  .hero .vaani {
    font-size: 3rem;
  }
  .hero .subtitle {
    font-size: 1.1rem;
  }
  .hero-info {
    flex-direction: column;
    gap: 15px;
  }
  .section-title {
    font-size: 2.2rem;
  }
  .timeline::before {
    left: 10px;
  }
  .timeline-item {
    width: 100%;
    padding-left: 50px;
    padding-right: 20px;
  }
  .timeline-item:nth-child(even) {
    left: 0;
  }
  .timeline-dot {
    left: -8.5px;
  }
  .timeline-item:nth-child(odd) .timeline-dot,
  .timeline-item:nth-child(even) .timeline-dot {
    right: auto;
    left: -8.5px;
  }
  .timeline-item:nth-child(odd) .timeline-content {
    text-align: left;
    border-right: none;
    border-left: 4px solid var(--accent-color);
  }
}