/* Variables */
:root {
    --bg-color: #fafafa;
    --card-bg: #ffffff;
    --text-color: #2c3e50;
    --text-light: #5a6c7d;
    --primary-color: #27ae60;
    --primary-dark: #229954;
    --secondary-color: #34495e;
    --border-color: #e1e8ed;
    --code-bg: #f4f6f8;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    --radius: 6px;
}

/* Reset */
* {
    margin: 0;
    padding: 0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    min-height: 100vh;
}

/* Navigation */
.navbar {
    background-color: var(--card-bg);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    text-decoration: none;
    user-select: none;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    pointer-events: none;
}

.logo i {
    font-size: 1.8rem;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-menu a {
    color: var(--text-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--primary-color);
}

.nav-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-color);
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
    flex: 1;
}

/* Hero Section */
.hero {
    position: relative;
    text-align: center;
    padding: 6rem 2rem;
    background-image: url('../images/zitro-hero.png'); 
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    margin-bottom: 3rem;
    color: white;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(15, 23, 42, 0.85); /* Fond bleu nuit très sombre avec opacité pour la lisibilité */
    z-index: 1;
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 2.8rem;
    margin-bottom: 1rem;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.hero .lead {
    font-size: 1.25rem;
    margin-bottom: 2.5rem;
    opacity: 0.9;
    line-height: 1.6;
}


.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius);
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    border: 2px solid transparent;
}

.btn-primary {
    background-color: white;
    color: var(--primary-color);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.btn-secondary {
    background-color: transparent;
    color: white;
    border-color: white;
}

.btn-secondary:hover {
    background-color: white;
    color: var(--primary-color);
}

/* Features */
.features {
    margin-bottom: 3rem;
}

.features h2 {
    text-align: center;
    margin-bottom: 2rem;
    font-size: 2rem;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}

.card {
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    text-align: center;
    transition: transform 0.3s;
}

.card:hover {
    transform: translateY(-5px);
}

.card i {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.card h3 {
    margin-bottom: 0.5rem;
    color: var(--secondary-color);
}

/* Quick Start */
.quick-start {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.quick-start h2 {
    margin-bottom: 1rem;
}

/* Code Blocks */
.code-block {
    background-color: var(--code-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 1rem;
    overflow-x: auto;
    margin: 1rem 0;
}

.code-block pre {
    margin: 0;
}

.code-block code {
    font-family: 'Courier New', Courier, monospace;
    font-size: 0.9rem;
    color: var(--text-color);
}

/* Content Sections */
.content-section {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    margin-bottom: 2rem;
}

.content-section h2 {
    color: var(--secondary-color);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.content-section h2 i {
    color: var(--primary-color);
}

.content-section h3 {
    margin: 1.5rem 0 0.75rem;
    color: var(--text-color);
}

.content-section ul,
.content-section ol {
    margin-left: 1.5rem;
    margin-bottom: 1rem;
}

.content-section li {
    margin-bottom: 0.5rem;
}

.content-section p {
    margin-bottom: 1rem;
}

/* Tables */
.table {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
    background-color: var(--card-bg);
    border-radius: var(--radius);
    overflow: hidden;
}

.table th,
.table td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.table th {
    background-color: var(--secondary-color);
    color: white;
    font-weight: 600;
}

.table tr:hover {
    background-color: var(--bg-color);
}

/* Alerts */
.alert {
    padding: 1rem;
    border-radius: var(--radius);
    margin: 1rem 0;
    display: flex;
    gap: 0.75rem;
    align-items: flex-start;
}

.alert-info {
    background-color: #e3f2fd;
    border-left: 4px solid #2196f3;
}

.alert i {
    font-size: 1.2rem;
    color: #2196f3;
}

/* Grade Cards */
.grade-card {
    padding: 1rem;
    border-radius: var(--radius);
    text-align: center;
    border: 2px solid;
}

.grade-a {
    border-color: #27ae60;
    background-color: #e8f5e9;
}

.grade-b {
    border-color: #8bc34a;
    background-color: #f1f8e9;
}

.grade-c {
    border-color: #ffc107;
    background-color: #fffde7;
}

.grade-d {
    border-color: #ff9800;
    background-color: #fff3e0;
}

.grade-e {
    border-color: #f44336;
    background-color: #ffebee;
}

.grade-f {
    border-color: #9c27b0;
    background-color: #fce4ec;
}

/* Metrics */
.metric-card {
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: var(--radius);
    text-align: center;
    box-shadow: var(--shadow);
}

.metric-card i {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.metric-weight {
    font-weight: bold;
    color: var(--primary-color);
    margin-top: 0.5rem;
}

/* Formula */
.formula {
    background-color: var(--code-bg);
    padding: 1.5rem;
    border-radius: var(--radius);
    text-align: center;
    margin: 1rem 0;
    font-size: 1.1rem;
    font-weight: 600;
    border-left: 4px solid var(--primary-color);
}

/* Command sections */
.command {
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: var(--radius);
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow);
}

.command h3 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

/* Footer */
.footer {
    background-color: #1a2e1f; /* Vert forêt très sombre, presque noir */
    color: #e0e0e0;
    text-align: center;
    padding: 2rem;
    margin-top: auto;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin: 1rem 0;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin: 1rem 0;
}

.footer-links a:hover {
    color: var(--primary-color);
    transform: translateY(-3px);
    text-decoration: none;
}

.footer a {
    color: #8fbc8f;
    text-decoration: none;
    margin: 0 0.5rem;
}

.footer a:hover {
    text-decoration: underline;
    color: #27ae60;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background-color: var(--card-bg);
        flex-direction: column;
        padding: 1rem;
        box-shadow: var(--shadow);
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .nav-toggle {
        display: block;
    }
    
    .hero h1 {
        font-size: 1.8rem;
    }
    
    .hero .lead {
        font-size: 1rem;
    }
    
    .grid {
        grid-template-columns: 1fr;
    }
    
    .container {
        padding: 1rem;
    }
    
    .content-section {
        padding: 1rem;
    }
    
    .table {
        font-size: 0.85rem;
    }
    
    .table th,
    .table td {
        padding: 0.5rem;
    }
}

/* Table grade colors */
tr.grade-a {
    background-color: #e8f5e9;
}

tr.grade-b {
    background-color: #f1f8e9;
}

tr.grade-c {
    background-color: #fffde7;
}

tr.grade-d {
    background-color: #fff3e0;
}

tr.grade-e {
    background-color: #ffebee;
}

tr.grade-f {
    background-color: #fce4ec;
}