/* CORPS DE LA PAGE */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  margin: 0;
  padding: 0;
  font-family: Verdana, Geneva, Tahoma, sans-serif;
  background-color: #0A0A0A;
  color: #E6ECEF;
  width: 100%;
}





/* HEADER */
/* ------------------------------------------------------------------ */

.header {
  width: 100%;
  background-color: #0A0A0A;
  position: sticky;
  top: 0;
  z-index: 999;
  border-bottom: 2px solid #CCCCCC;
}

/* topbar */
.header-topbar {
  background-color: #111111;
  color: #FFFFFF;
  font-size: 12px;
  padding: 6px 20px;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  border-bottom: 2px solid #CCCCCC;
}

.topbar-right a {
  margin-left: 15px;
  color: #FFFFFF;
  text-decoration: none;
  transition: all 0.3s ease;
}

.topbar-right a:hover {
  background-color: #FFFFFF;
  color: #000000;
  padding: 2px 6px;
  border-radius: 4px;
}

/* barre principale */
.header-main {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 40px;
  width: 100%;
}

/* logo */
.logo img {
  height: 50px;
  width: 50px;
  border: 2px solid #CCCCCC;
  border-radius: 8px;
}

/* navigation (menu) */
.nav {
  display: flex;
  align-items: center;
  position: relative;
}

.nav-list {
  display: flex;
  gap: 45px;
  list-style: none;
}

.nav-link {
  color: #FFFFFF;
  text-decoration: none;
  font-weight: 600;
  font-size: 15px;
  padding: 10px 14px;   
  line-height: 1;
  border-radius: 6px;
}

.nav-link:hover {
  background-color: #E6ECEF;
  color: #000000;
  box-shadow: 0 0 8px rgba(255,255,255,0.2);
}

.nav-toggle {
  display: none;      
  position: relative; 
  z-index: 1001;      
}






/* CONTENU */
/* ------------------------------------------------------------------ */

.container {
  max-width: 1140px;
  margin: auto;
  padding: 20px 20px 40px;
  width: 100%;
}

/* titre */
.page-title{
  text-align: center;
  font-size: 80px;
  line-height: 1.05;
  margin: 12px auto 16px;
  font-weight: 800;
  color: #E6ECEF;
}

.page-title::after{
  content: '';
  display: block;
  width: min(100%, 1140px);
  height: 2px;
  margin: 12px auto 0;
  background: #BFDFFF;
}

.title {
  font-size: 35px;
  color: #E6ECEF;
  margin-top: 80px;
  margin-bottom: 30px;
}

/* phrase en dessous des petits titres dans les blocs */
.intro-section {
  font-size: 20px;
  color: #E6ECEF;
  margin: 0 0 30px 0;
  text-align: left;
  padding-left: 20px;
  line-height: 1.8;
}


/* BLOC INFRASTRUCTURE */
.bloc-carte-infrastructure {
  border: 2px solid #BFDFFF;
  border-radius: 12px;
  padding: 30px 10px;
  background-color: #000000;
  width: 100%;
  text-align: center;
  margin-bottom: 40px;
}

/* bloc carte infrastucture */
.bloc-carte-infrastructure > div {
  display: inline-block;
  margin-right: 25px;
  margin-top: 40px;
  margin-bottom: 30px;
  vertical-align: top;
}

/* BLOC MATHEMATIQUES */
.bloc-carte-mathematiques {
  border: 2px solid #BFDFFF;
  border-radius: 12px;
  padding: 30px 10px;
  background-color: #000000;
  width: 100%;
  text-align: center;
  margin-bottom: 40px;
}

/* bloc carte mathematiques */
.bloc-carte-mathematiques > div {
  display: inline-block;
  margin-right: 25px;
  margin-top: 40px;
  margin-bottom: 30px;
  vertical-align: top;
}


/* BLOC DATA MANAGEMENT */
.bloc-carte-datamanagement {
  border: 2px solid #BFDFFF;
  border-radius: 12px;
  padding: 30px 10px;
  background-color: #000000;
  width: 100%;
  text-align: center;
  margin-bottom: 40px;
}

/* bloc carte data management */
.bloc-carte-datamanagement > div {
  display: inline-block;
  margin-right: 25px;
  margin-top: 40px;
  margin-bottom: 30px;
  vertical-align: top;
}


/* BLOC DIGITALS SKILLS */
.bloc-carte-digitals {
  border: 2px solid #BFDFFF;
  border-radius: 12px;
  padding: 30px 10px;
  background-color: #000000;
  width: 100%;
  text-align: center;
  margin-bottom: 40px;
}

/* bloc carte digitals skills */
.bloc-carte-digitals > div {
  display: inline-block;
  margin-right: 25px;
  margin-top: 40px;
  margin-bottom: 30px;
  vertical-align: top;
}


/* BLOC CYBERSECURITE */
.bloc-carte-cybersecurite {
  border: 2px solid #BFDFFF;
  border-radius: 12px;
  padding: 30px 10px;
  background-color: #000000;
  width: 100%;
  text-align: center;
  margin-bottom: 40px;
}

/* bloc carte cybersecurite */
.bloc-carte-cybersecurite > div {
  display: inline-block;
  margin-right: 25px;
  margin-top: 40px;
  margin-bottom: 30px;
  vertical-align: top;
}





/* carte */
.flip-carte {
  background-color: transparent;
  width: 300px;
  height: 300px;
}

/* derriere de la carte */
.carte-interieur {
  position: relative;
  width: 300px;
  height: 300px;
  text-align: center;
  transition: transform 0.8s;
  transform-style: preserve-3d;
}

/* effet derriere de la carte */
.flip-carte:hover .carte-interieur {
  transform: rotateY(180deg);
}

/* configuration des cartes devant (images) et derriere (listes) */
.carte-devant, .carte-derriere {
  position: absolute;
  width: 300px;
  height: 300px;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

/* carte devant */
.carte-devant {
  color: black;
}

/* image carte devant */
.carte-devant img {
  width: 300px;
  height: 300px;
  object-fit: cover;
  border: 2px solid #BFDFFF;
  border-radius: 12px;
}

/* liste derriere de la carte */
.carte-derriere {
  background-color: #2A2A2A;
  color: #E6ECEF;
  transform: rotateY(180deg);
  padding: 15px;
  border: 2px solid #BFDFFF;
  border-radius: 12px;
  line-height: 1.6;
  text-align: justify;
  font-size: 15px;
}





/* FOOTER */
/* ------------------------------------------------------- */

.footer {
  background-color: #0e0e0e;
  color: #E6ECEF;
  padding: 40px 20px 10px;
  font-size: 14px;
  border-top: 2px solid #CCCCCC;
  font-family: Verdana, Geneva, Tahoma, sans-serif;
}

.footer-container {
  display: flex;
  justify-content: space-around;
  flex-wrap: wrap;
  max-width: 1200px;
  margin: auto;
  gap: 30px;
}

.footer-section h4 {
  color: #E6ECEF;
  font-size: 15px;
  margin-bottom: 10px;
  text-transform: uppercase;
}

.footer-section ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-section li {
  margin-bottom: 6px;
}

.footer-section a {
  color: #E6ECEF;
  text-decoration: none;
  transition: 0.2s ease;
}

.footer-section a:hover {
  color: #CCCCCC; 
}

.footer-bottom {
  text-align: center;
  margin-top: 10px;
  font-size: 15px;
  color: #E6ECEF;
}

.footer-divider {
  width: 80%;
  max-width: 4000px;
  margin-top: 15px;
  border-top: 1px solid #CCCCCC;
  width: 100%;
}

.scroll-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background-color: #CCCCCC;
  color: #000;
  text-decoration: none;
  font-size: 20px;
  font-weight: bold;
  padding: 8px 12px;
  border-radius: 8px;
  opacity: 0.7;
  transition: all 0.3s ease;
  z-index: 999;
}

.scroll-top:hover {
  opacity: 1;
  transform: scale(1.1);
}





/* RESPONSIVE */
/* ------------------------------------------------------- */

@media (max-width: 768px) {

  .header { 
    z-index: 9990; 
  }

  .header-main {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
  }

  .logo img { 
    width: 40px; 
    height: 40px; 
  }

  .nav-toggle {
    display: flex;
    flex-direction: column;
    justify-content: space-around;
    width: 32px;
    height: 26px;
    cursor: pointer;
    margin-left: auto;
    position: relative;
    z-index: 10001;
  }

  .nav-toggle span {
    height: 3px;
    background-color: #FFFFFF;   
    border-radius: 2px;
    display: block;
  }

  .nav-list { 
    display: none; 
  }

  .nav-list.active {
    display: flex;
    flex-direction: column;
    gap: 14px;
    position: fixed;
    top: 64px;        
    left: 0; 
    right: 0; 
    bottom: 0;
    padding: 16px;
    background-color: #0A0A0A;
    border-top: 1px solid #CCCCCC;
    z-index: 10000;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
  }

  .nav-link { 
    display: block; 
    padding: 14px 10px; 
  }

  .nav-list li { 
    margin: 0; 
    text-align: left; 
  }

  .page-title{
    font-size: 36px;
    margin: 16px auto;
  }

  .title {
    font-size: 24px;
    margin: 16px auto;
  }


  .intro-section {
    font-size: 16px;
    line-height: 1.7;
    padding-left: 0;
    margin-bottom: 16px;
    text-align: justify;
  }

  .container { 
    padding: 24px 16px; 
  }

  .bloc-carte-infrastructure,
  .bloc-carte-mathematiques,
  .bloc-carte-datamanagement,
  .bloc-carte-digitals,
  .bloc-carte-cybersecurite {
    padding: 16px 8px;
    text-align: center;
  }

  .bloc-carte-infrastructure > div,
  .bloc-carte-mathematiques > div,
  .bloc-carte-datamanagement > div,
  .bloc-carte-digitals > div,
  .bloc-carte-cybersecurite > div {
    display: grid !important;
    grid-template-columns: 1fr;  
    gap: 12px;
    margin: 0;                   
  }

  .flip-carte {
    width: 100%;
    max-width: 360px;             
    margin: 0 auto 16px;
    height: auto;
    aspect-ratio: 1 / 1;          
  }

  .carte-interieur,
  .carte-devant,
  .carte-derriere {
    width: 100%;
    height: 100%;
  }

  .carte-devant img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 12px;
  }

  .carte-derriere {
    font-size: 14px;
    line-height: 1.6;
    padding: 12px;
    text-align: left;
  }

  .campus-section .media-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .campus-section .media-grid img {
    width: 100%;
    height: auto;
    aspect-ratio: 1 / 1;
    object-fit: cover;
  }

  .bts-section p,
  .bts-section ul {
    font-size: 16px;
    line-height: 1.7;
    padding: 0;
    margin-bottom: 12px;
  }

  .footer-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .scroll-top {
    bottom: 18px;
    right: 18px;
    font-size: 18px;
    padding: 8px 10px;
  }
  
}