/* ==========================================================================
 *  CSS Onconux - Barre de navigation centrée et Responsive
 *  ========================================================================== */

/* 1. Conteneur principal de la navigation (Bande sombre) */
.nav-container {
    width: 100%;
    background-color: #2c3e50;
    box-shadow: 0 2px 5px rgba(0,0,0,0.15);
    position: relative;
    z-index: 999;
}

nav {
    max-width: 1100px;
    margin: 0 auto;
    text-align: center; /* Permet de centrer les éléments du menu sur PC */
}

/* 2. Liste principale du menu */
#nav {
list-style: none;
padding: 0;
margin: 0;
display: inline-block; /* Crucial pour le centrage horizontal exact */
}

#nav > li {
display: block;
float: left; /* Aligne les onglets horizontalement sur PC */
position: relative;
}

#nav a {
display: block;
color: #ffffff;
text-decoration: none;
font-weight: 600;
font-size: 15px;
padding: 15px 20px;
transition: background-color 0.2s ease, color 0.2s ease;
}

/* Changement de couleur au survol de la souris */
#nav li:hover > a {
background-color: #34495e;
color: #3182ce;
}

/* 3. Premier niveau de sous-menu (Ex: Énergies, Alcool) */
#nav ul.submenu {
display: none; /* Caché par défaut, s'affiche au survol */
position: absolute;
top: 100%;
left: 0;
background-color: #34495e;
min-width: 220px;
list-style: none;
padding: 0;
margin: 0;
box-shadow: 0 4px 8px rgba(0,0,0,0.2);
text-align: left;
}

#nav ul.submenu li {
width: 100%;
position: relative;
border-bottom: 1px solid #2c3e50;
}

#nav ul.submenu li a {
padding: 12px 20px;
font-size: 14px;
color: #ecf0f1;
}

/* Affichage du premier sous-menu au survol */
#nav li:hover > ul.submenu {
display: block;
}

/* 4. Deuxième niveau de sous-menu (Ex: Plomberie / Chauffage) */
#nav ul.submenu-nested {
display: none;
position: absolute;
top: 0;
left: 100%; /* S'ouvre sur le côté droit */
background-color: #1a252f;
min-width: 220px;
list-style: none;
padding: 0;
margin: 0;
box-shadow: 0 4px 8px rgba(0,0,0,0.2);
}

/* Affichage du sous-menu imbriqué au survol */
#nav ul.submenu li:hover > ul.submenu-nested {
display: block;
}

/* Flèches indicatrices pour les menus déroulants sur PC */
@media (min-width: 769px) {
    #nav li.has-submenu > a::after {
    content: " ▾";
    font-size: 12px;
    opacity: 0.7;
    }
    #nav ul.submenu li.has-submenu > a::after {
    content: " ▸";
    float: right;
    }
    .hamburger-btn, .menu-toggle {
        display: none !important; /* Force la disparition du bouton mobile sur PC */
    }
}



:root {
    --primary: #1e3a8a;
    --secondary: #eab308;
    --dark: #334155;
    --light: #f8fafc;
    --border: #cbd5e1;
}

*, *::before, *::after {
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    line-height: 1.6;
    color: var(--dark);
    background-color: #ffffff;
    margin: 0;
    padding: 0;
}

.container {
    max-width: 960px;
    margin: 0 auto;
    padding: 0 20px;
}

header {
    background: linear-gradient(135deg, var(--primary), #3b82f6);
    color: white;
    padding: 30px 0 10px 0;
    text-align: center;
}

header h1 { margin: 0 0 10px 0; font-size: 2.2rem; }
.subtitle { margin: 0 0 25px 0; opacity: 0.9; font-size: 1.1rem; }

nav {
    display: flex;
    justify-content: center;
    gap: 15px;
    flex-wrap: wrap;
}

nav a {
    color: white;
    text-decoration: none;
    padding: 8px 16px;
    border-radius: 4px;
    background: rgba(255, 255, 255, 0.1);
    transition: background 0.2s;
}

nav a:hover, nav a.active {
    background: var(--secondary);
    color: var(--primary);
    font-weight: bold;
}

main { padding: 40px 0; }
section { margin-bottom: 40px; }
h2 { color: var(--primary); border-bottom: 2px solid var(--light); padding-bottom: 10px; }

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.card {
    background: var(--light);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 20px;
}

.note {
    background: #fef9c3;
    border-left: 5px solid var(--secondary);
    padding: 20px;
    border-radius: 4px;
    margin-top: 30px;
}

.calculator-box {
    background: var(--light);
    border: 2px solid var(--primary);
    border-radius: 8px;
    padding: 25px;
}

.checkbox-group label {
    display: block;
    margin-bottom: 12px;
    font-size: 1.1rem;
    cursor: pointer;
}

.results-box {
    margin-top: 25px;
    padding-top: 20px;
    border-top: 2px dashed var(--border);
}

.badge {
    padding: 15px;
    border-radius: 6px;
    font-weight: bold;
    margin-top: 10px;
}
.badge-info { background: #e0f2fe; color: #0369a1; }
.badge-success { background: #dcfce7; color: #15803d; }
.badge-warning { background: #fef9c3; color: #a16207; }
.badge-danger { background: #fee2e2; color: #b91c1c; }

/* Styles spécifiques aux conteneurs de schémas */
.schema-container {
    background: #ffffff;
    padding: 20px;
    border: 1px solid var(--border);
    border-radius: 8px;
    text-align: center;
    margin-top: 20px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
}

.schema-container svg {
    width: 100%;
    height: auto;
    display: block;
    margin: 0 auto;
    max-width: 760px;
}

.legend {
    margin-top: 15px;
    padding-top: 10px;
    border-top: 1px solid var(--light);
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--dark);
}

hr {
    border: 0;
    height: 1px;
    background: var(--border);
    margin: 40px 0;
}

footer {
    text-align: center;
    padding: 20px 0;
    background: var(--light);
    border-top: 1px solid var(--border);
    color: #64748b;
}