/* --- Variables de Couleur & Styles de Base --- */
:root {
    --primary-color: #1B2A41;
    --secondary-color: #3A506B;
    --accent-color: #FFC107;
    --electric-glow: #00BFFF;
    --text-color: #333;
    --light-text-color: #F8F9FA;
    --light-gray-bg: #F8F9FA;
    --white: #ffffff;
    --box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    --header-height: 80px;
    --font-primary: 'Montserrat', sans-serif;
    --font-secondary: 'Roboto', sans-serif;
}

/* --- Keyframes --- */
@keyframes electric-glow{0%{box-shadow:0 0 5px var(--accent-color),0 0 10px var(--accent-color)}50%{box-shadow:0 0 20px var(--electric-glow),0 0 30px var(--electric-glow)}100%{box-shadow:0 0 5px var(--accent-color),0 0 10px var(--accent-color)}}
@keyframes text-flicker{0%,100%{text-shadow:0 0 2px var(--light-text-color);opacity:1}50%{text-shadow:none;opacity:.95}}
@keyframes hero-slideshow{0%{opacity:0;animation-timing-function:ease-in}8%{opacity:1}17%{opacity:1}25%{opacity:0;animation-timing-function:ease-out}100%{opacity:0}}
@keyframes lightbox-zoom { from {transform: scale(0.8);} to {transform: scale(1);} }

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
    font-family: var(--font-secondary);
    color: var(--text-color);
    background-color: var(--white);
    line-height: 1.6;
    padding-top: var(--header-height);
}
body.nav-open { overflow: hidden; }

@media (max-width: 768px) {
  body {
    padding-top: 100px; /* correspond au header plus grand sur mobile */
  }
}

main { padding-top: 0; }

/* --- Utilitaires --- */
.fade-in-element{opacity:0;transform:translateY(20px);transition:opacity .6s ease-out,transform .6s ease-out}
.fade-in-element.is-visible{opacity:1;transform:translateY(0)}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);border:0}

/* --- Header & Navigation --- */
.header{
    position:fixed;
    top:0;
    left:0;
    width:100%;
    display:flex;
    justify-content:space-between;
    align-items:center;
    height:var(--header-height);
    padding:0 3rem;
    z-index:1000;
    background-color:transparent;
    transition:background-color .3s ease-in-out,box-shadow .3s ease-in-out
}
.header.scrolled{background-color:rgba(255,255,255,.95);backdrop-filter:blur(10px);box-shadow:0 2px 5px rgba(0,0,0,.05)}
.header-logo{display:flex;align-items:center;text-decoration:none;z-index:1001}
.header-logo img{height:80px;width:auto}
.main-nav{display:flex}
.main-nav ul{list-style:none;display:flex;gap:2.5rem;margin:0}
.main-nav a{text-decoration:none;color:var(--white);font-weight:500;position:relative;padding:.5rem 0;overflow:hidden;transition:color .3s ease,text-shadow .3s ease}
.main-nav a:hover{text-shadow:0 0 5px var(--electric-glow)}
.main-nav a::after{content:'';position:absolute;width:100%;height:2px;bottom:0;left:0;background-color:var(--accent-color);transform:scaleX(0);transform-origin:center;transition:transform .4s ease-out}
.main-nav a:hover::after{transform:scaleX(1)}
.header.scrolled .main-nav a{color:var(--primary-color)}
.header.mobile-open {background-color: rgba(27, 42, 65, 0.98);backdrop-filter: blur(15px);box-shadow: 0 2px 5px rgba(0,0,0,0.1);}
.header.mobile-open .main-nav a {color: var(--light-text-color);}



/* --- Bouton du menu mobile --- */
.mobile-nav-toggle{display:none;position:relative;z-index:1001;background:transparent;border:0;width:2em;height:2em;cursor:pointer}
.mobile-nav-toggle .icon-hamburger,.mobile-nav-toggle .icon-close{position:absolute;inset:0;margin:auto;width:100%;height:3px;background:var(--white);transition:transform .3s ease-out,opacity .2s ease-out}
.mobile-nav-toggle .icon-hamburger::before,.mobile-nav-toggle .icon-hamburger::after{content:'';position:absolute;left:0;width:100%;height:100%;background:var(--white);transition:transform .3s ease-out}
.mobile-nav-toggle .icon-hamburger::before{transform:translateY(-8px)}
.mobile-nav-toggle .icon-hamburger::after{transform:translateY(8px)}
.header.scrolled .mobile-nav-toggle .icon-hamburger,.header.scrolled .mobile-nav-toggle .icon-hamburger::before,.header.scrolled .mobile-nav-toggle .icon-hamburger::after{background:var(--primary-color)}
.mobile-nav-toggle .icon-close{background:transparent}
.mobile-nav-toggle .icon-close::before,.mobile-nav-toggle .icon-close::after{content:'';position:absolute;left:0;width:100%;height:100%;background:var(--white)}
.mobile-nav-toggle .icon-close::before{transform:rotate(45deg)}
.mobile-nav-toggle .icon-close::after{transform:rotate(-45deg)}
.mobile-nav-toggle[aria-expanded=false] .icon-close{opacity:0;transform:rotate(45deg)}
.mobile-nav-toggle[aria-expanded=true] .icon-hamburger{opacity:0;transform:rotate(-45deg)}

/* --- Sections --- */
.hero-section{position:relative;height:100vh;margin-top:calc(-1 * var(--header-height));display:flex;align-items:center;justify-content:center;text-align:center;color:var(--white);overflow:hidden}
.hero-slide{position:absolute;top:0;left:0;width:100%;height:100%;background-size:cover;background-position:center;opacity:0;animation:hero-slideshow 48s infinite;transform:scale(1.1)}
.hero-slide:nth-child(2){animation-delay:4s}
.hero-slide:nth-child(3){animation-delay:8s}
.hero-slide:nth-child(4){animation-delay:12s}
.hero-slide:nth-child(5){animation-delay:16s}
.hero-slide:nth-child(6){animation-delay:20s}
.hero-slide:nth-child(7){animation-delay:24s}
.hero-slide:nth-child(8){animation-delay:28s}
.hero-slide:nth-child(9){animation-delay:32s}
.hero-slide:nth-child(10){animation-delay:36s}
.hero-slide:nth-child(11){animation-delay:40s}
.hero-slide:nth-child(12){animation-delay:44s}
.hero-overlay{position:absolute;top:0;left:0;width:100%;height:100%;background-color:rgba(27,42,65,.7);z-index:1}
.hero-content{position:relative;z-index:2;padding:0 1rem}
.hero-content h1 {
    font-size: clamp(2.5rem, 5vw, 4rem);
    margin-bottom: 1.5rem;
}
.hero-content p {
    font-size: clamp(1rem, 2.5vw, 1.3rem); 
}
.cta-button{background-color:var(--accent-color);color:var(--primary-color);padding:.8rem 1.8rem;border-radius:50px;text-decoration:none;font-weight:700;font-family:var(--font-primary);transition:all .3s ease;border:none;cursor:pointer;font-size:1rem}
.cta-button:hover{background-color:var(--primary-color);color:var(--accent-color);transform:translateY(-3px);animation:electric-glow 1.5s infinite}
.content-section{padding:5rem 3rem;text-align:center}
.content-section h2{font-family:var(--font-primary);font-size:clamp(2rem,4vw,2.5rem);margin-bottom:3rem;color:var(--primary-color)}
.bg-light{background-color:var(--light-gray-bg)}
.cards-container{display:flex;justify-content:center;gap:1.5rem;flex-wrap:wrap}
.card{background:var(--white);border-radius:10px;box-shadow:var(--box-shadow);width:340px;padding:2rem;transition:transform .3s ease,box-shadow .3s ease;text-align:center;border:2px solid transparent}
.card:hover{transform:translateY(-10px);box-shadow:0 10px 20px rgba(0,0,0,.15)}
.card-icon{width:100%;height:180px;object-fit:cover;border-radius:8px;margin-bottom:1.5rem}
.card h3{font-family:var(--font-primary);color:var(--secondary-color);margin-bottom:1rem}
.realisations-container{display:grid;grid-template-columns:repeat(auto-fit,minmax(350px,1fr));gap:1.5rem}
.realisation-card{background:var(--white);border-radius:10px;box-shadow:var(--box-shadow);padding:1.5rem;overflow:hidden;transition:transform .3s ease}
.realisation-card:hover{transform:translateY(-10px);box-shadow:0 15px 25px rgba(0,0,0,.15)}
.realisation-card h3{font-family:var(--font-primary);color:var(--primary-color);font-size:1.8rem;margin-bottom:1.5rem;transition:transform .3s ease}
.realisation-card:hover h3{transform:translateY(-5px)}
.realisation-images{display:grid;grid-template-columns:1fr;gap:1rem}
.realisation-images img{width:100%;height:250px;object-fit:cover;border-radius:8px;transition:transform .4s ease,box-shadow .4s ease;cursor:pointer}
.realisation-card:hover .realisation-images img{transform:scale(1.05);box-shadow:0 8px 15px rgba(0,0,0,.2)}
.contact-section{background:linear-gradient(to right,var(--secondary-color),var(--primary-color))}
.contact-section h2{color:var(--white)}
.contact-wrapper{display:flex;gap:3rem;max-width:1000px;margin:0 auto;background:var(--white);padding:3rem;border-radius:10px;box-shadow:var(--box-shadow);align-items:flex-start;text-align: left;}
.contact-info{flex:1;text-align:left}
.contact-info h3{color:var(--primary-color);font-family:var(--font-primary);margin-bottom:1.5rem}
.contact-info p{margin-bottom:1rem}
.contact-info a{color:var(--secondary-color);text-decoration:none;font-weight:500}
.contact-form{flex:1.5}
.form-group{margin-bottom:1rem}
.form-group input,.form-group textarea{width:100%;padding:1rem;border:1px solid #ccc;border-radius:5px;font-size:1rem;font-family:var(--font-secondary)}
.contact-logo{max-width:200px;margin-bottom:1.5rem;display:block;margin-left:auto;margin-right:auto}
.footer{background-color:var(--primary-color);color:var(--light-text-color);text-align:center;padding:2rem;font-size:.9rem}

/* --- Styles de la Lightbox --- */
.lightbox {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.9);
}
.lightbox-content {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    max-width: 90%;
    max-height: 85%;
    animation: lightbox-zoom 0.5s ease-out;
}
.lightbox-close {
    position: absolute;
    top: 30px;
    right: 45px;
    color: var(--white);
    font-size: 40px;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.3s ease;
}
.lightbox-close:hover { color: var(--accent-color); }
.lightbox-prev, .lightbox-next {
    cursor: pointer;
    position: absolute;
    top: 50%;
    width: auto;
    padding: 16px;
    margin-top: -30px;
    color: var(--white);
    font-weight: bold;
    font-size: 30px;
    transition: 0.3s ease;
    user-select: none;
}
.lightbox-next { right: 0; border-radius: 3px 0 0 3px; }
.lightbox-prev { left: 0; border-radius: 0 3px 3px 0; }
.lightbox-prev:hover, .lightbox-next:hover { background-color: rgba(255, 255, 255, 0.1); }

/* --- Responsive --- */
@media (max-width: 768px) {
  .main-nav,
  .mobile-nav-toggle {
    display: none !important;
  }
  .header-logo img {
    display: block;
    height: 80px;
    margin: 0 auto;
  }
  .header {
    justify-content: center;
  }
}