/**
* Modern Tech Conference Redesign for EDiS'2026
*/

:root {
  --c-primary: #2563EB;
  --c-primary-hover: #1D4ED8;
  --c-accent: #E11D48;
  --c-dark: #0F172A;
  
  --bg-page: #FAFAFA;
  --bg-surface: #FFFFFF;
  --bg-surface-alt: #F1F5F9;
  
  --t-heading: #0F172A;
  --t-body: #334155; 
  --t-muted: #64748B;

  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  
  --shadow-sm: 0 4px 6px -1px rgba(0,0,0,0.05);
  --shadow-md: 0 10px 15px -3px rgba(0,0,0,0.05);
  --shadow-lg: 0 20px 40px -5px rgba(15,23,42,0.1);
  --shadow-float: 0 30px 60px -10px rgba(37,99,235,0.15);
  --shadow-glow: 0 0 20px rgba(37,99,235,0.2);
  
--f-display: Arial, Helvetica, sans-serif;
--f-body: Arial, Helvetica, sans-serif;
}

body {
  background-color: var(--bg-page);
  color: var(--t-body);
  font-family: var(--f-body);
  font-size: 1.05rem; 
  font-weight: 400;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--f-display);
  color: var(--t-heading);
  font-weight: 700;
  letter-spacing: -0.02em;
}

a {
  color: var(--c-primary);
  text-decoration: none;
  transition: all 0.3s ease;
}

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

.text-accent { color: var(--c-accent); }
.bg-light-alt { background-color: var(--bg-surface-alt); }

.modern-section {
  padding: 100px 0;
  position: relative;
}

.section-heading {
  margin-bottom: 60px;
}

.section-heading h2 {
  font-size: clamp(2.5rem, 4vw, 3.5rem);
  font-weight: 800;
  margin-bottom: 15px;
  line-height: 1.1;
}

.section-heading p {
  font-size: 1.2rem;
  color: var(--t-muted);
  max-width: 600px;
}

.section-heading.text-center p {
  margin-left: auto;
  margin-right: auto;
}

/* Header */
#header {
  position: fixed;
  top: 20px;
  left: 0;
  right: 0;
  z-index: 997;
  transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  padding: 0 20px;
}

.header-container {
  max-width: 1200px;
  margin: 0 auto;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.4);
  border-radius: 100px;
  padding: 10px 20px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
  transition: all 0.3s ease;
}

#header.header-scrolled .header-container {
  background: rgba(255, 255, 255, 0.98);
  box-shadow: 0 15px 40px rgba(0, 0, 0, 0.08);
}

.logo-img { height: 45px; transition: height 0.3s ease; }
.lapeci-logo { height: 28px; border-left: 1px solid #e2e8f0; padding-left: 12px; }

.navbar ul {
  display: flex; list-style: none; margin: 0; padding: 0; align-items: center;
}
.navbar li { padding: 0 5px; }
.navbar a {
  font-family: var(--f-body);
  font-weight: 500;
  font-size: 0.85rem;
  color: var(--t-heading);
  padding: 6px 10px;
  border-radius: 100px;
  transition: 0.3s;
}
.navbar a:hover, .navbar .active {
  background: rgba(37, 99, 235, 0.08);
  color: var(--c-primary);
}

.btn-primary-modern {
  background: var(--c-primary);
  color: #fff !important;
  padding: 12px 28px;
  border-radius: 100px;
  font-weight: 600;
  font-family: var(--f-body);
  box-shadow: 0 4px 15px rgba(37, 99, 235, 0.3);
  transition: all 0.3s ease;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 2px solid var(--c-primary);
}
.btn-primary-modern:hover {
  background: transparent;
  color: var(--c-primary) !important;
  transform: translateY(-2px);
  box-shadow: none;
}

.btn-outline-modern {
  background: transparent;
  color: var(--t-heading) !important;
  padding: 12px 28px;
  border-radius: 100px;
  font-weight: 600;
  border: 2px solid #E2E8F0;
  transition: all 0.3s;
}
.btn-outline-modern:hover {
  border-color: var(--c-dark);
  color: var(--c-dark) !important;
}

.mobile-nav-toggle {
  color: var(--t-heading);
  font-size: 28px; cursor: pointer; display: none; margin-left: 15px;
}
@media (max-width: 991px) {
  .mobile-nav-toggle { display: block; }
  .navbar ul { display: none; }
  .header-container { border-radius: 20px; }

  .navbar.navbar-mobile ul {
    display: flex !important;
    flex-direction: column;
    position: fixed;
    top: 90px;
    left: 15px;
    right: 15px;
    background: rgba(255, 255, 255, 0.98);
    border-radius: 20px;
    padding: 10px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.15);
    z-index: 9999;
  }

  .navbar.navbar-mobile ul li {
    width: 100%;
    padding: 0;
  }

  .navbar.navbar-mobile ul li a {
    width: 100%;
    display: block;
    padding: 14px 20px;
    font-size: 1rem;
    color: var(--t-heading);
    border-radius: 12px;
  }

  .navbar.navbar-mobile ul li a:hover {
    background: rgba(37, 99, 235, 0.08);
    color: var(--c-primary);
  }
}

/* Hero Section */
.hero-modern {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 80px;
  position: relative;
}

.hero-content {
  position: relative;
  z-index: 1;
  width: 100%;
  display: flex;
  justify-content: flex-start;
}

/* Modifié : réduction de la taille et de l'espacement pour que ce soit moins imposant */
.hero-text-box {
  background: rgba(255, 255, 255, 0.92); 
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  padding: 35px; /* Réduit (auparavant 40px) */
  border-radius: var(--radius-lg);
  max-width: 480px; /* Réduit (auparavant 550px) */
  box-shadow: var(--shadow-lg);
  border: 1px solid rgba(255,255,255,0.5);
  text-align: left; 
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background: #fff;
  border: 1px solid #E2E8F0;
  padding: 8px 18px;
  border-radius: 100px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--t-heading);
  margin-bottom: 20px; /* Réduit (auparavant 25px) */
  box-shadow: var(--shadow-sm);
}

.pulse-dot {
  width: 8px; height: 8px;
  background: var(--c-accent);
  border-radius: 50%;
  box-shadow: 0 0 0 0 rgba(225, 29, 72, 0.7);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(225, 29, 72, 0.7); }
  70% { transform: scale(1); box-shadow: 0 0 0 10px rgba(225, 29, 72, 0); }
  100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(225, 29, 72, 0); }
}


.hero-title {
  font-size: clamp(1.8rem, 3.2vw, 2.8rem); 
  font-weight: 900;
  line-height: 1.15; 
  letter-spacing: -0.02em;
  margin-bottom: 15px; 
}

.gradient-text {
  background: linear-gradient(135deg, var(--c-primary) 0%, #8b5cf6 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.15rem);
  color: var(--t-body);
  margin-bottom: 30px;
}

.hero-actions {
  display: flex; gap: 15px; justify-content: flex-start; margin-top: 20px;
}

@media (max-width: 768px) {
  .hero-text-box {
    padding: 25px 20px;
  }
}

/* About Bento Grid */
.bento-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.bento-card {
  background: var(--bg-surface);
  border-radius: var(--radius-lg);
  padding: 40px;
  border: 1px solid #E2E8F0;
  box-shadow: var(--shadow-sm);
  transition: all 0.3s ease;
}

.bento-card:hover { box-shadow: var(--shadow-md); transform: translateY(-3px); }

.span-2 { grid-column: span 2; }
.span-1 { grid-column: span 1; }

.bento-main h3, .bento-dates h3 {
  font-size: 2rem; margin-bottom: 20px; font-weight: 800;
}

.bg-accent {
  background: var(--c-primary);
  border: none;
  color: #fff;
  background-image: linear-gradient(135deg, var(--c-primary) 0%, #4338ca 100%);
}
.bg-accent h3 { color: #fff; }

.timeline-list { list-style: none; padding: 0; margin: 0; }
.timeline-list li {
  display: flex; justify-content: space-between; align-items: center;
  padding: 15px 0; border-bottom: 1px solid rgba(255,255,255,0.15);
  font-size: 1.05rem;
}
.timeline-list li:last-child { border-bottom: none; }
.timeline-list li span { opacity: 0.8; }
.timeline-highlight {
  background: rgba(255,255,255,0.15);
  padding: 15px !important;
  border-radius: var(--radius-sm);
  margin-top: 10px;
}
.timeline-highlight b { font-size: 1.25rem; color: #fff;}

.news-header { display: flex; align-items: center; gap: 10px; margin-bottom: 20px; color: var(--c-accent);}
.news-header h3 { margin: 0; font-size: 1.5rem; color: var(--t-heading); }
.news-header i { font-size: 1.5rem; animation: pulse 2s infinite; border-radius: 50%;}

.news-item { background: var(--bg-surface-alt); padding: 25px; border-radius: var(--radius-md); }
.news-date { display: inline-block; font-size: 0.85rem; font-weight: 700; color: var(--c-primary); text-transform: uppercase; margin-bottom: 8px; letter-spacing: 1px;}
.news-item p { margin: 0; font-size: 1.05rem; line-height: 1.6;}

@media (max-width: 992px) {
  .bento-grid { grid-template-columns: 1fr; }
  .span-2, .span-1 { grid-column: span 1; }
}

/* Topics Grid */
.topics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 20px;
}

.topic-card {
  background: var(--bg-surface);
  border: 1px solid #E2E8F0;
  border-top-width: 4px;
  border-radius: var(--radius-md);
  padding: 30px;
  transition: all 0.3s ease;
  overflow: hidden;
}

.topic-card:hover {
  background: var(--bg-surface);
  box-shadow: 0 10px 25px rgba(0,0,0,0.06);
  transform: translateY(-5px);
}

.topic-icon {
  width: 55px; height: 55px;
  border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.5rem; 
  margin-bottom: 20px; 
  transition: all 0.3s ease;
}

.border-top-blue { border-top-color: #3B82F6; }
.border-top-indigo { border-top-color: #6366F1; }
.border-top-cyan { border-top-color: #06B6D4; }
.border-top-purple { border-top-color: #A855F7; }
.border-top-orange { border-top-color: #F59E0B; }
.border-top-pink { border-top-color: #EC4899; }
.border-top-green { border-top-color: #10B981; }
.border-top-rose { border-top-color: #E11D48; }

.icon-blue { color: #3B82F6; background: rgba(59, 130, 246, 0.1); }
.icon-indigo { color: #6366F1; background: rgba(99, 102, 241, 0.1); }
.icon-cyan { color: #06B6D4; background: rgba(6, 182, 212, 0.1); }
.icon-purple { color: #A855F7; background: rgba(168, 85, 247, 0.1); }
.icon-orange { color: #F59E0B; background: rgba(245, 158, 11, 0.1); }
.icon-pink { color: #EC4899; background: rgba(236, 72, 153, 0.1); }
.icon-green { color: #10B981; background: rgba(16, 185, 129, 0.1); }
.icon-rose { color: #E11D48; background: rgba(225, 29, 72, 0.1); }

.topic-card:hover .topic-icon { color: #fff; }
.topic-card:hover .icon-blue { background: #3B82F6; }
.topic-card:hover .icon-indigo { background: #6366F1; }
.topic-card:hover .icon-cyan { background: #06B6D4; }
.topic-card:hover .icon-purple { background: #A855F7; }
.topic-card:hover .icon-orange { background: #F59E0B; }
.topic-card:hover .icon-pink { background: #EC4899; }
.topic-card:hover .icon-green { background: #10B981; }
.topic-card:hover .icon-rose { background: #E11D48; }

.topic-card h4 { font-size: 1.25rem; margin-bottom: 10px; color: var(--t-heading); }
.topic-card p { margin: 0; font-size: 0.95rem; color: var(--t-muted); line-height: 1.5; }


/* Keynote Speakers Redesigned Grid (Small photo, clickable abstract) */
.speakers-modern-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 25px;
}

.speaker-card {
  transition: all 0.3s ease;
}

.speaker-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md) !important;
}

.speaker-topic {
  color: var(--t-body);
  font-size: 1.05rem;
  line-height: 1.4;
}


/* COMMITTEES GRID SYSTEM */
.committee-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}

.committee-block {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 30px;
  border: 1px solid #E2E8F0;
  box-shadow: var(--shadow-sm);
  height: 100%;
}

.committee-title {
  font-size: 1.35rem;
  margin-bottom: 20px;
  padding-bottom: 15px;
  border-bottom: 2px solid var(--bg-surface-alt);
}

.chair-card {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--t-heading);
  padding: 12px 0;
  border-bottom: 1px solid #F1F5F9;
}
.chair-card:last-child { border-bottom: none; }
.chair-card small { 
  display: block; 
  font-size: 0.9rem; 
  font-weight: 400; 
  color: var(--t-muted); 
  margin-top: 4px; 
}

/* Program Committee Accordion Grid */
.modern-accordion .accordion-item {
  border: 1px solid #E2E8F0;
  background: var(--bg-surface);
  border-radius: var(--radius-lg) !important;
  margin-bottom: 15px;
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}

.modern-accordion .accordion-button {
  background: transparent;
  padding: 24px 30px;
  font-family: var(--f-display);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--t-heading);
  box-shadow: none !important;
}

.modern-accordion .accordion-button:not(.collapsed) {
  color: var(--c-primary);
  background: rgba(37, 99, 235, 0.02);
}

.modern-accordion .accordion-body {
  padding: 0 30px 30px 30px;
  background: rgba(37, 99, 235, 0.02);
}

.pc-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 15px;
}

.pc-name {
  background: #fff;
  border: 1px solid #E2E8F0;
  padding: 12px 15px;
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--t-heading);
  display: flex;
  flex-direction: column;
}

.pc-name span {
  font-size: 0.8rem;
  font-weight: 400;
  color: var(--t-muted);
  margin-top: 2px;
}

/* Action Hub */
.action-bento-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
@media (max-width: 992px) { .action-bento-grid { grid-template-columns: 1fr; } }

.bg-gradient-primary { background: linear-gradient(135deg, var(--c-primary) 0%, #6366f1 100%); }

.icon-circle, .icon-circle-alt {
  width: 80px; height: 80px;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 2.5rem;
}
.icon-circle { background: rgba(255,255,255,0.2); }
.icon-circle-alt { background: rgba(37, 99, 235, 0.1); }

.action-card { transition: transform 0.3s ease, box-shadow 0.3s ease; }
.action-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-float) !important; }

/* Past Editions Row-based Design */
.past-edition-row {
  display: flex; 
  align-items: center; 
  background: rgba(255, 255, 255, 0.05); 
  border: 1px solid rgba(255, 255, 255, 0.15); 
  border-radius: var(--radius-md); 
  padding: 15px; 
  text-decoration: none; 
  transition: all 0.3s ease;
}

.past-edition-row:hover { 
  background: rgba(255, 255, 255, 0.1); 
  transform: translateX(10px); 
  border-color: rgba(255, 255, 255, 0.3);
}

.past-edition-row img { 
  width: 140px; 
  height: 90px; 
  object-fit: cover; 
  border-radius: var(--radius-sm); 
  margin-right: 25px; 
  background: #222;
}

.pe-info h4 { 
  color: #fff; 
  margin: 0 0 5px 0; 
  font-size: 1.4rem;
}

.pe-info span { 
  color: var(--c-primary); 
  font-size: 0.95rem; 
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.pe-icon { 
  color: #fff; 
  font-size: 1.5rem; 
  transition: transform 0.3s ease;
}

.past-edition-row:hover .pe-icon {
  transform: translateX(5px);
  color: var(--c-primary);
}

@media (max-width: 576px) {
  .past-edition-row img { width: 100px; height: 70px; margin-right: 15px;}
  .pe-info h4 { font-size: 1.1rem; }
}

/* Sponsors */
.sponsor-grid {
  display: grid; 
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); 
  gap: 20px;
}

.sponsor-logo-box {
  background: #fff; 
  border: 1px solid #E2E8F0;
  border-radius: var(--radius-md);
  height: 120px; /* Hauteur de la case agrandie */
  display: flex; align-items: center; justify-content: center;
  padding: 15px; transition: all 0.3s ease;
}

.sponsor-logo-box img { 
  max-width: 100%; 
  max-height: 100%; 
  transition: all 0.3s ease; 
}
.sponsor-logo-box:hover { 
  border-color: var(--c-primary); 
  box-shadow: var(--shadow-sm); 
  transform: translateY(-3px);
}
.sponsor-logo-box:hover img { filter: grayscale(0); opacity: 1; }

/* Footer */
.modern-footer { background: var(--bg-surface); border-top: 1px solid #E2E8F0; padding: 60px 0 40px 0; }
.footer-logo { color: var(--t-heading); }
.footer-logo:hover { color: var(--c-primary); }

.back-to-top {
  position: fixed; right: 30px; bottom: 30px; z-index: 996;
  width: 50px; height: 50px; border-radius: 50%;
  background: var(--t-heading); color: #fff;
  visibility: hidden; opacity: 0; transition: all 0.4s;
  box-shadow: var(--shadow-md);
}
.back-to-top i { font-size: 24px; line-height: 0; }
.back-to-top:hover { background: var(--c-primary); color: #fff; transform: translateY(-5px); }
.back-to-top.active { visibility: visible; opacity: 1; }

/* --- MULTI-PAGE HEADER STYLE --- */
.page-header {
  padding: 180px 0 80px 0;
  background: linear-gradient(135deg, rgba(15, 23, 42, 0.85), rgba(37, 99, 235, 0.8));
  color: #fff;
  text-align: center;
}
.page-header h1 {
  color: #fff;
  font-size: clamp(2.5rem, 4vw, 3.5rem);
  font-weight: 800;
  margin-bottom: 15px;
}
.page-header p {
  font-size: 1.2rem;
  opacity: 0.9;
  max-width: 600px;
  margin: 0 auto;
}

@media (max-width: 768px) {
  .header-container,
  .hero-text-box {
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }

  .hero-modern {
    min-height: auto;
    padding: 120px 0 60px;
  }
}