:root {
  --primary-color: #2c3e50;
  --secondary-color: #34495e;
  --accent-color: #3498db;
  --gradient-start: #2c3e50;
  --gradient-end: #3498db;
  --text-color: #2c3e50;
  --light-bg: #f8f9fa;
  --white: #ffffff;
  --shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
  --card-shadow: 0 8px 25px rgba(0, 0, 0, 0.08);
  --hover-shadow: 0 12px 30px rgba(0, 0, 0, 0.12);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Cairo', sans-serif;
}

body {
  background-color: var(--light-bg);
  color: var(--text-color);
  line-height: 1.6;
}

header {
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  color: var(--white);
  padding: 3rem 0;
  text-align: center;
  box-shadow: var(--shadow);
  position: relative;
  overflow: hidden;
}

header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('../images/pattern.png');
  opacity: 0.1;
  z-index: 1;
}

header h1 {
  font-size: 2.5rem;
  margin-bottom: 1.5rem;
  font-weight: 700;
}

.logos-container {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 3rem;
  margin: 2rem 0;
  position: relative;
  z-index: 2;
}

.logo-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  transition: all 0.4s ease;
  background: rgba(255, 255, 255, 0.1);
  padding: 1.5rem;
  border-radius: 15px;
  backdrop-filter: blur(5px);
}

.logo-item:hover {
  transform: translateY(-10px);
  background: rgba(255, 255, 255, 0.2);
}

.logo-item img {
  width: 150px;
  height: 150px;
  object-fit: contain;
  margin-bottom: 1rem;
  filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.2));
  transition: all 0.4s ease;
}

.logo-item:hover img {
  transform: scale(1.1);
}

.logo-item span {
  color: var(--white);
  font-size: 1.1rem;
  font-weight: 500;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.conference-date {
  font-size: 1.2rem;
  margin-top: 1rem;
}

nav {
  background-color: var(--white);
  padding: 1rem;
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: var(--shadow);
}

nav a, .dropdown-trigger {
  color: var(--text-color);
  text-decoration: none;
  padding: 0.5rem 1rem;
  margin: 0 0.5rem;
  border-radius: 5px;
  transition: all 0.3s ease;
  font-weight: 500;
}

nav a:hover, .dropdown-trigger:hover {
  background: var(--section-gradient);
  color: var(--white);
  box-shadow: 0 4px 15px rgba(44, 62, 80, 0.15);
}

.dropdown {
  position: relative;
  display: inline-block;
}

.dropdown-content {
  display: none;
  position: absolute;
  background-color: var(--white);
  min-width: 200px;
  box-shadow: var(--shadow);
  border-radius: 5px;
  z-index: 1;
}

.dropdown:hover .dropdown-content {
  display: block;
}

.dropdown-content a {
  display: block;
  padding: 0.8rem 1rem;
}

.section {
  background-color: var(--white);
  margin: 2rem auto;
  padding: 2rem;
  max-width: 1200px;
  border-radius: 10px;
  box-shadow: var(--shadow);
}

.section h2 {
  color: var(--section-color);
  margin-bottom: 2rem;
  text-align: center;
  font-size: 2.2rem;
  position: relative;
  padding-bottom: 1rem;
  text-shadow: none;
}

.section h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 150px;
  height: 4px;
  background: var(--section-gradient);
  border-radius: 2px;
  box-shadow: 0 2px 4px rgba(44, 62, 80, 0.08);
}

.topics {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
}

.topics ul {
  list-style: none;
}

.topics li {
  padding: 0.8rem;
  margin: 0.5rem 0;
  background-color: var(--light-bg);
  border-radius: 5px;
  transition: transform 0.3s ease;
}

.topics li:hover {
  transform: translateX(10px);
  background-color: var(--accent-color);
  color: var(--white);
}

.speakers-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: 3rem;
  padding: 2rem 0;
}

.speaker-card, .committee-card {
  background: var(--white);
  border-radius: 15px;
  overflow: hidden;
  box-shadow: var(--card-shadow);
  transition: all 0.4s cubic-bezier(0.165, 0.84, 0.44, 1);
  border: 1px solid rgba(44, 62, 80, 0.08);
  border-top: 4px solid var(--section-color);
}

.speaker-card:hover, .committee-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--hover-shadow);
  border-top-color: var(--accent-color);
  border-color: rgba(44, 62, 80, 0.15);
}

.speaker-image {
  position: relative;
  height: 450px;
  overflow: hidden;
  background: var(--light-bg);
  display: flex;
  align-items: center;
  justify-content: center;
}

.speaker-image::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(to bottom, transparent 50%, rgba(0, 0, 0, 0.7));
  z-index: 1;
}

.speaker-image img {
  width: auto;
  height: 100%;
  max-width: 100%;
  object-fit: contain;
  transition: transform 0.5s cubic-bezier(0.165, 0.84, 0.44, 1);
}

.speaker-card:hover .speaker-image img {
  transform: scale(1.05);
}

.speaker-info {
  padding: 2rem;
  background: var(--white);
  position: relative;
  z-index: 2;
}

.speaker-info h3 {
  color: var(--primary-color);
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  line-height: 1.4;
}

.university-info {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  padding: 1.2rem;
  background: var(--light-bg);
  border-radius: 12px;
  transition: all 0.3s ease;
}

.university-info:hover {
  background: var(--accent-color);
  color: var(--white);
}

.university-logo {
  width: 60px;
  height: 60px;
  border-radius: 12px;
  object-fit: contain;
  background: var(--white);
  padding: 0.5rem;
  transition: all 0.3s ease;
}

.university-info:hover .university-logo {
  transform: scale(1.1);
}

.university-details {
  flex: 1;
}

.university-details p {
  font-size: 1.1rem;
  font-weight: 600;
  margin: 0 0 0.5rem 0;
}

.country-info {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.country-flag {
  width: 24px;
  height: 16px;
  border-radius: 4px;
  object-fit: cover;
}

.country-info span {
  font-size: 0.9rem;
  font-weight: 500;
}

.speaker-bio {
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--light-bg);
}

.speaker-bio p {
  color: var(--text-color);
  font-size: 1rem;
  line-height: 1.6;
  margin: 0;
}

.committee-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  padding: 2rem 0;
}

.committee-card img {
  width: auto;
  height: 350px;
  max-width: 100%;
  object-fit: contain;
  margin: 1rem auto;
  display: block;
  border-radius: 15px;
  transition: all 0.4s ease;
  background: var(--light-bg);
  padding: 0.5rem;
}

.committee-card:hover img {
  transform: scale(1.05);
}

.committee-card h3 {
  color: var(--primary-color);
  font-size: 1.3rem;
  margin: 1rem 0;
  text-align: center;
  font-weight: 700;
}

.committee-card p {
  color: var(--text-color);
  text-align: center;
  padding: 0 1rem 1.5rem;
  font-size: 1.1rem;
}

.date-card {
  background: var(--white);
  padding: 2rem;
  border-radius: 15px;
  text-align: center;
  transition: all 0.4s ease;
  box-shadow: var(--card-shadow);
  position: relative;
  overflow: hidden;
  border: 1px solid rgba(44, 62, 80, 0.08);
  border-top: 4px solid var(--section-color);
}

.date-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 5px;
  background: linear-gradient(to right, var(--gradient-start), var(--gradient-end));
}

.date-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--hover-shadow);
  border-top-color: var(--accent-color);
  border-color: rgba(44, 62, 80, 0.15);
}

.date-icon {
  width: 70px;
  height: 70px;
  background: var(--light-bg);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem;
  transition: all 0.4s ease;
  color: var(--section-color);
  box-shadow: 0 4px 15px rgba(44, 62, 80, 0.08);
}

.date-card:hover .date-icon {
  background: var(--section-gradient);
  color: var(--white);
  box-shadow: 0 4px 15px rgba(44, 62, 80, 0.15);
}

.date-icon i {
  font-size: 2rem;
}

.date-content h3 {
  color: var(--primary-color);
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
  font-weight: 600;
}

.date-content p {
  color: var(--text-color);
  font-size: 1.3rem;
  font-weight: 700;
}

.contact-container {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 2rem;
}

.contact-info {
  background-color: var(--light-bg);
  padding: 2rem;
  border-radius: 10px;
  width: 100%;
  max-width: 600px;
}

.contact-item {
  display: flex;
  align-items: center;
  margin: 1rem 0;
  padding: 1rem;
  background-color: var(--white);
  border-radius: 5px;
  transition: transform 0.3s ease;
}

.contact-item:hover {
  transform: translateX(10px);
}

.contact-item i {
  font-size: 1.5rem;
  margin-right: 1rem;
  color: var(--accent-color);
}

footer {
  background-color: var(--primary-color);
  color: var(--white);
  text-align: center;
  padding: 1.5rem;
  margin-top: 3rem;
}

@media (max-width: 768px) {
  header h1 {
    font-size: 1.8rem;
  }
  
  .logos-container {
    flex-direction: column;
    gap: 2rem;
  }
  
  .logo-item {
    width: 100%;
    max-width: 300px;
  }
  
  .speakers-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
    padding: 1rem;
  }
  
  .speaker-image {
    height: 400px;
  }
  
  .speaker-info {
    padding: 1.5rem;
  }
  
  .speaker-info h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
  }
  
  .university-info {
    padding: 1rem;
    gap: 1rem;
  }
  
  .university-logo {
    width: 50px;
    height: 50px;
  }
  
  .university-details p {
    font-size: 1rem;
  }
  
  .committee-card img {
    height: 300px;
  }
  
  .date-card {
    padding: 1.5rem;
  }
  
  .date-icon {
    width: 60px;
    height: 60px;
  }
  
  nav {
    padding: 0.5rem;
  }
  
  nav a, .dropdown-trigger {
    display: block;
    margin: 0.5rem 0;
    text-align: center;
  }
  
  .section {
    margin: 1rem;
    padding: 1rem;
  }
}

/* تخصيص الألوان لكل قسم */
#keynote {
  --section-color: #1a237e;
  --section-gradient: linear-gradient(135deg, #1a237e, #283593);
}

#Internationalscientific {
  --section-color: #0d47a1;
  --section-gradient: linear-gradient(135deg, #0d47a1, #1565c0);
}

#supervisory {
  --section-color: #311b92;
  --section-gradient: linear-gradient(135deg, #311b92, #4527a0);
}

#editorial {
  --section-color: #1a237e;
  --section-gradient: linear-gradient(135deg, #1a237e, #283593);
}

#scientific {
  --section-color: #0d47a1;
  --section-gradient: linear-gradient(135deg, #0d47a1, #1565c0);
}

#organizing {
  --section-color: #311b92;
  --section-gradient: linear-gradient(135deg, #311b92, #4527a0);
}

/* تنسيق الجداول */
.editorial-table, .scientific-table {
  background: var(--white);
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--card-shadow);
  margin: 2rem 0;
  border: 1px solid rgba(26, 35, 126, 0.1);
}

.editorial-row, .scientific-row {
  display: flex;
  padding: 1.5rem;
  border-bottom: 1px solid var(--light-bg);
  transition: all 0.3s ease;
  background: var(--white);
  border-right: 4px solid var(--section-color);
}

.editorial-row:hover, .scientific-row:hover {
  background: var(--light-bg);
  transform: translateX(10px);
  border-right-color: var(--accent-color);
}

.editorial-cell:first-child, .scientific-cell:first-child {
  font-weight: 600;
  color: var(--section-color);
}

.editorial-cell {
  flex: 1;
  padding: 0 1rem;
  font-size: 1.1rem;
  color: var(--text-color);
}

.scientific-cell {
  flex: 1;
  padding: 0 1rem;
  font-size: 1.1rem;
  color: var(--text-color);
}

/* تنسيق البطاقات */
.speaker-card, .committee-card {
  background: var(--white);
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--card-shadow);
  transition: all 0.4s cubic-bezier(0.165, 0.84, 0.44, 1);
  border-top: 4px solid var(--section-color);
}

.speaker-card:hover, .committee-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--hover-shadow);
  border-top-color: var(--accent-color);
}

/* تحسين التجاوب */
@media (max-width: 768px) {
  .editorial-row {
    flex-direction: column;
    gap: 0.5rem;
  }
  
  .editorial-cell {
    padding: 0.5rem 0;
  }
  
  .section h2 {
    font-size: 1.8rem;
  }
}

#dates {
  --section-color: #1a237e;
  --section-gradient: linear-gradient(135deg, #1a237e, #283593);
}

.dates-timeline {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
  padding: 2rem 0;
  position: relative;
}

.dates-timeline::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--section-gradient);
  transform: translateY(-50%);
  z-index: 1;
  opacity: 0.2;
}

.date-card {
  background: var(--white);
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--card-shadow);
  transition: all 0.4s cubic-bezier(0.165, 0.84, 0.44, 1);
  position: relative;
  z-index: 2;
  padding: 2rem;
  border: 1px solid rgba(26, 35, 126, 0.1);
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.date-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--section-gradient);
  opacity: 0.8;
}

.date-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--hover-shadow);
}

.date-card:hover::before {
  opacity: 1;
}

.date-icon {
  width: 80px;
  height: 80px;
  background: var(--light-bg);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem;
  transition: all 0.4s ease;
  color: var(--section-color);
  font-size: 2rem;
  position: relative;
  z-index: 2;
}

.date-icon::after {
  content: '';
  position: absolute;
  top: -5px;
  left: -5px;
  right: -5px;
  bottom: -5px;
  border-radius: 50%;
  background: var(--section-gradient);
  opacity: 0.1;
  z-index: -1;
  transition: all 0.4s ease;
}

.date-card:hover .date-icon {
  background: var(--section-gradient);
  color: var(--white);
  transform: scale(1.1);
}

.date-card:hover .date-icon::after {
  opacity: 0.2;
  transform: scale(1.2);
}

.date-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.date-content h3 {
  color: var(--section-color);
  font-size: 1.2rem;
  margin-bottom: 1rem;
  font-weight: 600;
  line-height: 1.4;
}

.date-content p {
  color: var(--text-color);
  font-size: 1.4rem;
  font-weight: 700;
  background: var(--light-bg);
  padding: 0.5rem 1.5rem;
  border-radius: 10px;
  display: inline-block;
  margin: 0 auto;
  transition: all 0.3s ease;
}

.date-card:hover .date-content p {
  background: var(--section-gradient);
  color: var(--white);
  transform: scale(1.05);
}

@media (max-width: 768px) {
  .dates-timeline {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  
  .dates-timeline::before {
    display: none;
  }
  
  .date-card {
    padding: 1.5rem;
  }
  
  .date-icon {
    width: 70px;
    height: 70px;
    font-size: 1.8rem;
  }
  
  .date-content h3 {
    font-size: 1.1rem;
  }
  
  .date-content p {
    font-size: 1.2rem;
  }
}

/* تحسينات للهواتف المحمولة */
@media (max-width: 480px) {
  header {
    padding: 1.5rem 0.5rem;
    min-height: auto;
  }

  header h1 {
    font-size: 1.3rem;
    margin-bottom: 0.8rem;
    padding: 0 0.5rem;
    line-height: 1.4;
  }

  .logos-container {
    flex-direction: column;
    gap: 1rem;
    margin: 1rem 0;
    padding: 0 0.5rem;
  }

  .logo-item {
    width: 100%;
    max-width: 200px;
    padding: 0.8rem;
    margin: 0 auto;
  }

  .logo-item img {
    width: 100px;
    height: 100px;
    margin-bottom: 0.5rem;
  }

  .logo-item span {
    font-size: 0.9rem;
    text-align: center;
  }

  .conference-date {
    font-size: 1rem;
    margin-top: 0.5rem;
    padding: 0 0.5rem;
  }

  header::before {
    opacity: 0.05;
  }

  .section {
    margin: 1rem 0.5rem;
    padding: 1rem;
  }

  .section h2 {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
  }

  .speakers-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
    padding: 0.5rem;
  }

  .speaker-image {
    height: 300px;
  }

  .speaker-info {
    padding: 1rem;
  }

  .speaker-info h3 {
    font-size: 1.2rem;
    margin-bottom: 0.8rem;
  }

  .university-info {
    padding: 0.8rem;
    gap: 0.8rem;
  }

  .university-logo {
    width: 40px;
    height: 40px;
  }

  .university-details p {
    font-size: 0.9rem;
  }

  .committee-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .committee-card img {
    height: 250px;
  }

  .committee-card h3 {
    font-size: 1.1rem;
  }

  .committee-card p {
    font-size: 0.9rem;
    padding: 0 0.5rem 1rem;
  }

  .dates-timeline {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .date-card {
    padding: 1rem;
  }

  .date-icon {
    width: 60px;
    height: 60px;
    font-size: 1.5rem;
  }

  .date-content h3 {
    font-size: 1rem;
  }

  .date-content p {
    font-size: 1.1rem;
    padding: 0.4rem 1rem;
  }

  .contact-container {
    padding: 1rem;
  }

  .contact-info {
    padding: 1rem;
  }

  .contact-item {
    padding: 0.8rem;
    margin: 0.8rem 0;
  }

  .contact-item i {
    font-size: 1.2rem;
  }

  nav {
    padding: 0.5rem;
  }

  nav a, .dropdown-trigger {
    padding: 0.4rem 0.8rem;
    margin: 0.3rem 0;
    font-size: 0.9rem;
  }

  .dropdown-content {
    min-width: 180px;
  }

  .dropdown-content a {
    padding: 0.6rem 0.8rem;
    font-size: 0.9rem;
  }

  .editorial-row, .scientific-row {
    padding: 1rem;
    flex-direction: column;
    gap: 0.5rem;
  }

  .editorial-cell, .scientific-cell {
    padding: 0.3rem 0;
    font-size: 0.9rem;
  }
}

/* تحسينات إضافية للشاشات الصغيرة جداً */
@media (max-width: 320px) {
  header {
    padding: 1rem 0.3rem;
  }

  header h1 {
    font-size: 1.1rem;
    margin-bottom: 0.6rem;
  }

  .logo-item {
    max-width: 180px;
    padding: 0.6rem;
  }

  .logo-item img {
    width: 80px;
    height: 80px;
  }

  .logo-item span {
    font-size: 0.8rem;
  }

  .conference-date {
    font-size: 0.9rem;
  }

  .section h2 {
    font-size: 1.3rem;
  }

  .speaker-image {
    height: 250px;
  }

  .date-icon {
    width: 50px;
    height: 50px;
    font-size: 1.3rem;
  }
}

/* تنسيق القائمة المنسدلة للهواتف */
.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--white);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0.5rem;
  position: absolute;
  right: 1rem;
  top: 1rem;
  z-index: 1001;
}

@media (max-width: 768px) {
  .mobile-menu-toggle {
    display: block;
  }

  nav {
    position: fixed;
    top: 0;
    right: -100%;
    width: 80%;
    max-width: 300px;
    height: 100vh;
    background: var(--primary-color);
    padding: 4rem 1rem 1rem;
    transition: right 0.3s ease;
    z-index: 1000;
    overflow-y: auto;
  }

  nav.active {
    right: 0;
  }

  nav a, .dropdown-trigger {
    display: block;
    color: var(--white);
    padding: 0.8rem 1rem;
    margin: 0.5rem 0;
    border-radius: 5px;
    text-align: right;
  }

  .dropdown {
    width: 100%;
  }

  .dropdown-content {
    position: static;
    background: rgba(255, 255, 255, 0.1);
    box-shadow: none;
    width: 100%;
    display: none;
    padding: 0.5rem 0;
  }

  .dropdown.active .dropdown-content {
    display: block;
  }

  .dropdown-content a {
    padding: 0.6rem 1.5rem;
    color: var(--white);
    opacity: 0.9;
  }

  .overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 999;
  }

  .overlay.active {
    display: block;
  }
}

@media (max-width: 480px) {
  nav {
    width: 85%;
  }

  .mobile-menu-toggle {
    font-size: 1.3rem;
    top: 0.8rem;
    right: 0.8rem;
  }

  nav a, .dropdown-trigger {
    padding: 0.7rem 0.8rem;
    font-size: 0.95rem;
  }

  .dropdown-content a {
    padding: 0.5rem 1.2rem;
    font-size: 0.9rem;
  }
}