/* Variables globales et styles de base */
:root {
    --primary-color: #2c3e50;
    --secondary-color: #34495e;
    --accent-color: #3498db;
    --background-color: #f5f6fa;
    --text-color: #2c3e50;
    --border-radius: 8px;
    --box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    --header-height: 60px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.6;
    padding-top: var(--header-height);
}

header {
    background: white;
    box-shadow: var(--box-shadow);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    z-index: 1000;
}

.content {
    padding: 2rem;
    max-width: 1400px;
    margin: 0 auto;
}

/* Utilitaires */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border: none;
    border-radius: var(--border-radius);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

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

.btn-danger {
    background: #e74c3c;
    color: white;
}

.error {
    background: #fee;
    color: #e74c3c;
    padding: 0.75rem;
    border-radius: var(--border-radius);
    margin-bottom: 1.5rem;
}