:root {
    --primary: #2ecc71; /* Vert agriculture */
    --secondary: #2c3e50; /* Bleu pro / logiciel */
    --accent: #3498db;
    --white: #ffffff;
    --gray: #f4f7f6;
}

* { margin: 30; padding: 10; box-sizing: border-box; font-family: 'Segoe UI', sans-serif; }

/* Navigation */
header { background: var(--secondary); padding: 1rem 0; position: sticky; top: 0; z-index: 1000; }
nav { display: flex; justify-content: space-around; align-items: center; max-width: 1200px; margin: auto; }
.logo { color: white; font-size: 1.8rem; font-weight: bold; }
.logo span { color: var(--primary); }
nav ul { display: flex; list-style: none; }
nav ul li a { color: white; text-decoration: none; padding: 0.5rem 1rem; transition: 0.3s; }
nav ul li a:hover, .active { color: var(--primary); }

/* Hero Section */
.hero {
    background: linear-gradient(rgba(44, 62, 80, 0.8), rgba(44, 62, 80, 0.8)), 
                url('https://images.unsplash.com/photo-1516467508483-a7212febe31a?auto=format&fit=crop&w=1200');
    height: 70vh; background-size: cover; background-position: center;
    display: flex; flex-direction: column; justify-content: center; align-items: center;
    color: white; text-align: center;
}
.btn { background: var(--primary); color: white; padding: 12px 30px; text-decoration: none; border-radius: 30px; margin: 10px; display: inline-block; }
.btn-alt { background: var(--accent); }

/* WhatsApp Button */
.whatsapp-float {
    position: fixed; bottom: 20px; right: 20px;
    background: #25d366; color: white;
    padding: 15px 25px; border-radius: 50px;
    text-decoration: none; display: flex; align-items: center;
    box-shadow: 0 4px 10px rgba(0,0,0,0.3); z-index: 1000;
    transition: transform 0.3s;
}
.whatsapp-float:hover { transform: scale(1.1); }
.whatsapp-float i { font-size: 24px; margin-right: 10px; }

/* Footer */
footer { background: var(--secondary); color: white; text-align: center; padding: 2rem; }