/* Variables et Styles Généraux */
:root {
    --color-dark-blue: #0A192F;
    --color-light-blue: #66CCFF;
    --color-text: #E6E6E6;
    --color-grey: #30475E;
    --color-card-hover: #172A45;
    --color-cta-hover: #99FFFF;
}

/* --------------------------------- */
/* 🚀 1. Styles Généraux & Reset Minime */
/* --------------------------------- */
*, *::before, *::after {
    box-sizing: border-box; 
}

body {
    font-family: 'Arial', sans-serif;
    color: var(--color-text);
    margin: 0;
    padding: 0;
    line-height: 1.6;

    /* Image de fond */
    background-image: 
        linear-gradient(rgba(10, 25, 47, 0.2), rgba(10, 25, 47, 0.2)), 
        url('expertises.jpg'); 
    
    background-color: var(--color-dark-blue);
    background-size: cover; 
    background-position: center center; 
    background-attachment: fixed; 
}
 
/* --------------------------------- */
/* 🌐 2. En-tête (Navigation) */
/* --------------------------------- */
header {
    background-color: rgba(10, 25, 47, 0.95);
    padding: 15px 50px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 2px solid var(--color-light-blue);
}

/* Styles pour le logo */
.logo-container {
    display: flex;
    align-items: center;
    text-decoration: none;
}
.logo-img {
    height: 120px; 
    width: auto;
    margin-right: 10px;
}
.logo {
    font-size: 1.8em;
    font-weight: bold;
    color: var(--color-light-blue);
}
 
nav a {
    color: var(--color-text);
    text-decoration: none;
    margin-left: 25px;
    font-size: 1.1em;
    transition: color 0.3s;
}
nav a:hover, nav a.active {
    color: var(--color-light-blue);
}

/* Bouton d'Action (CTA) */
.cta-button {
    display: inline-block;
    background-color: var(--color-light-blue);
    color: var(--color-dark-blue);
    padding: 10px 20px;
    text-decoration: none;
    border-radius: 5px;
    font-weight: bold;
    font-size: 1em;
    transition: background-color 0.3s;
}
.cta-button:hover {
    background-color: var(--color-cta-hover);
}

/* --------------------------------- */
/* 🖼️ 3. Contenu Principal */
/* --------------------------------- */
.page-content {
    padding: 50px 80px;
    max-width: 1200px;
    margin: 0 auto;
}
.page-content h1 {
    text-align: center;
    font-size: 3em;
    color: var(--color-light-blue);
    margin-bottom: 20px;
}
.page-content p.intro {
    text-align: center;
    font-size: 1.2em;
    margin-bottom: 60px;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

/* --------------------------------- */
/* 🛠️ 4. Grille d'Expertises */
/* --------------------------------- */
.expertise-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); 
    gap: 30px;
}

/* Carte d'Expertise */
.expertise-card {
    background-color: var(--color-grey);
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    border-top: 5px solid var(--color-light-blue);
    transition: background-color 0.3s, transform 0.3s;
}
.expertise-card:hover {
    background-color: var(--color-card-hover);
    transform: translateY(-5px);
}
.expertise-card h3 {
    color: var(--color-light-blue);
    font-size: 1.8em;
    margin-top: 0;
    margin-bottom: 15px;
}
.expertise-card ul {
    list-style-type: none;
    padding-left: 0;
}
.expertise-card li {
    position: relative;
    padding-left: 20px;
    margin-bottom: 8px;
}
.expertise-card li::before {
    content: '▶';
    color: var(--color-light-blue);
    position: absolute;
    left: 0;
    font-size: 0.8em;
    line-height: 1.6;
}

/* --------------------------------- */
/* 🎯 5. Section Méthodologie */
/* --------------------------------- */
.methodology {
    padding: 60px 0;
    text-align: center;
    margin-top: 50px;
    background-color: var(--color-grey);
    border-radius: 10px;
}
.methodology h2 {
    color: var(--color-light-blue);
    margin-bottom: 30px;
}

.intro-methodology { 
    max-width: 800px;
    margin: 0 auto;
    font-size: 1.1em;
}
.methodology p {
    max-width: 800px;
    margin: 0 auto;
    font-size: 1.1em;
}

/* --------------------------------- */
/* 📜 6. Pied de Page */
/* --------------------------------- */
footer {
    background-color: var(--color-grey);
    text-align: center;
    padding: 20px;
    font-size: 0.9em;
    margin-top: 50px;
    border-top: 2px solid var(--color-light-blue);
}
footer a {
    color: var(--color-light-blue);
    text-decoration: none;
}

/* ========================================= */
/* 📱 7. MEDIA QUERIES (Affichage Mobile) */
/* ========================================= */
@media (max-width: 768px) {
    
    /* 1. Navigation et En-tête */
    header {
        padding: 15px 20px;
        flex-direction: column; 
        text-align: center;
    }
    .logo-img {
        height: 80px; 
    }
    nav {
        margin-top: 15px;
        display: flex;
        flex-direction: column; 
        width: 100%;
        **align-items: center;** /* Ajout pour renforcer le centrage des liens */
    }
    nav a {
        margin: 5px 0;
        padding: 8px 0;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
        width: 100%;
        text-align: center;
    }

    /* 🎯 CORRECTION DÉFINITIVE DU BOUTON "CONTACT" */
    .cta-button {
        margin-top: 10px;
        /* Remplacement de width: 100% pour permettre le centrage */
        **width: 90%;** **display: block;** **margin-left: auto;** /* Centrage Horizontal */
        **margin-right: auto;** /* Centrage Horizontal */
        text-align: center;
    }
    
    /* 2. Contenu Principal */
    .page-content {
        padding: 30px 20px; 
    }
    .page-content h1 {
        font-size: 2em;
    }
    .page-content p.intro {
        font-size: 1em;
    }

    /* 3. Grille d'Expertises */
    .expertise-grid {
        grid-template-columns: 1fr; /* Force la colonne unique */
        gap: 20px; 
    }
    .expertise-card {
        padding: 20px; 
    }
    .expertise-card h3 {
        font-size: 1.5em;
    }

    /* 4. Méthodologie */
    .methodology {
        padding: 40px 20px;
    }
    .methodology p, .intro-methodology { 
        font-size: 1em;
    }
}