/* --- VARIABLES & RESET --- */
:root {
    --primary: #003366; /* Bleu NVTECH */
    --secondary: #ff6600; /* Orange NVTECH */
    --text: #333;
    --light-bg: #f4f7f6;
    --white: #ffffff;
    --font: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    font-family: var(--font);
    line-height: 1.6;
    color: var(--text);
    background-color: var(--light-bg);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* --- HEADER & NAVIGATION --- */
header {
    background: var(--white);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar {
    max-width: 1200px;
    margin: 0 auto;
    padding: 15px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* Logo SVG stylisé */
.logo svg { height: 50px; width: auto; }

.nav-menu {
    list-style: none;
    display: flex;
    gap: 20px;
}

.nav-menu a {
    text-decoration: none;
    color: var(--primary);
    font-weight: 600;
    font-size: 0.9rem;
    text-transform: uppercase;
    transition: color 0.3s;
}

.nav-menu a:hover, .nav-menu a.active {
    color: var(--secondary);
    border-bottom: 2px solid var(--secondary);
}

/* --- HERO SECTION --- */
.hero {
    background: linear-gradient(rgba(0, 51, 102, 0.9), rgba(0, 51, 102, 0.8)), url('https://images.unsplash.com/photo-1519389950473-47ba0277781c?ixlib=rb-1.2.1&auto=format&fit=crop&w=1350&q=80');
    background-size: cover;
    background-position: center;
    color: var(--white);
    padding: 100px 20px;
    text-align: center;
}

.hero h1 { font-size: 3rem; margin-bottom: 20px; }
.hero p { font-size: 1.2rem; max-width: 800px; margin: 0 auto 30px; }
.btn {
    background: var(--secondary); color: var(--white);
    padding: 12px 30px; text-decoration: none; border-radius: 5px; font-weight: bold;
    transition: 0.3s;
}
.btn:hover { background: #e65c00; }

/* --- SECTIONS --- */
.container { max-width: 1200px; margin: 0 auto; padding: 60px 20px; }
.section-title {
    text-align: center; color: var(--primary); margin-bottom: 50px; font-size: 2.2rem;
    border-bottom: 3px solid var(--secondary); display: inline-block; padding-bottom: 10px;
}
.center-wrap { text-align: center; }

/* --- GRIDS & CARDS --- */
.grid-3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 30px; }
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 50px; align-items: center; }

.card {
    background: var(--white); border-radius: 8px; overflow: hidden;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05); transition: transform 0.3s;
}
.card:hover { transform: translateY(-5px); }
.card-img { height: 200px; background-size: cover; background-position: center; }
.card-content { padding: 25px; }
.card-content h3 { color: var(--primary); margin-bottom: 10px; }

/* --- PROCESS STEPS (About) --- */
.steps-container { display: flex; flex-wrap: wrap; justify-content: center; gap: 20px; margin-top: 30px; }
.step-circle {
    width: 140px; height: 140px; background: var(--primary); border-radius: 50%;
    display: flex; flex-direction: column; justify-content: center; align-items: center;
    color: var(--white); text-align: center; border: 4px solid var(--secondary);
}
.step-num { font-size: 1.5rem; font-weight: bold; color: var(--secondary); }

/* --- CONTACT FORM --- */
.contact-info { background: var(--primary); color: white; padding: 40px; border-radius: 8px; }
.contact-info a { color: white; text-decoration: none; }
.form-group { margin-bottom: 15px; }
.form-control { width: 100%; padding: 12px; border: 1px solid #ccc; border-radius: 4px; }
.btn-submit { width: 100%; border: none; cursor: pointer; font-size: 1rem; }

/* --- FOOTER --- */
footer { background: #1a1a1a; color: #ccc; padding: 60px 20px 20px; margin-top: auto; }
.footer-links ul { list-style: none; }
.footer-links a { color: #ccc; text-decoration: none; }
.footer-links a:hover { color: var(--secondary); }
.copyright { text-align: center; margin-top: 40px; padding-top: 20px; border-top: 1px solid #333; }

/* --- RESPONSIVE --- */
@media (max-width: 768px) {
    .navbar { flex-direction: column; gap: 15px; }
    .nav-menu { flex-direction: column; text-align: center; }
    .grid-2 { grid-template-columns: 1fr; }
}