:root {
    /* Palette de couleurs - Premium Dark mode */
    --primary: #3b82f6;
    --primary-dark: #2563eb;
    --primary-light: #60a5fa;
    --secondary: #8b5cf6;
    --secondary-dark: #7c3aed;
    --accent: #06b6d4;

    /* Couleurs sémantiques */
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --info: #3b82f6;

    /* Couleurs neutres (Dark Theme) */
    --bg-main: #0f172a;
    --bg-card: #1e293b;
    --bg-input: #334155;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --border-color: rgba(255, 255, 255, 0.1);

    /* Typographie */
    --font-primary: 'Inter', -apple-system, sans-serif;
    --font-heading: 'Outfit', 'Inter', sans-serif;

    /* Espacements */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;

    /* Border radius */
    --radius-sm: 0.5rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;

    /* Ombres & Glows */
    --shadow-glow: 0 0 20px rgba(59, 130, 246, 0.2);
    --shadow-xl: 0 25px 50px -12px rgba(0, 0, 0, 0.5);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* Reset & Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-primary);
    color: var(--text-main);
    background: var(--bg-main);
    background-image:
        radial-gradient(at 0% 0%, rgba(59, 130, 246, 0.15) 0px, transparent 50%),
        radial-gradient(at 100% 100%, rgba(139, 92, 246, 0.1) 0px, transparent 50%);
    min-height: 100vh;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* Typographie */
h1,
h2,
h3,
h4 {
    font-family: var(--font-heading);
    font-weight: 700;
    letter-spacing: -0.025em;
}

a {
    color: var(--primary-light);
    text-decoration: none;
    transition: all var(--transition-fast);
}

a:hover {
    color: var(--white);
    text-shadow: 0 0 8px rgba(59, 130, 246, 0.4);
}

/* Glassmorphism Cards */
.container {
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
}

.card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-xl);
    backdrop-filter: blur(10px);
    transition: transform var(--transition-base), border-color var(--transition-base);
}

.card:hover {
    border-color: rgba(59, 130, 246, 0.4);
    transform: translateY(-2px);
}

/* Boutons Premium */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: 0.75rem 1.5rem;
    font-weight: 600;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-base);
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
}

.btn-primary:hover {
    box-shadow: 0 8px 25px rgba(59, 130, 246, 0.5);
    transform: scale(1.02);
}

/* Formulaires */
.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-muted);
}

.form-input {
    width: 100%;
    padding: 0.75rem 1rem;
    background: var(--bg-input);
    border: 2px solid transparent;
    border-radius: var(--radius-md);
    color: white;
    transition: all var(--transition-fast);
}

.form-input:focus {
    outline: none;
    border-color: var(--primary);
    background: #1e293b;
    box-shadow: var(--shadow-glow);
}

/* Alerts */
.alert {
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    margin-bottom: var(--spacing-lg);
    font-size: 0.875rem;
}

.alert-danger {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid var(--danger);
    color: #fca5a5;
}

/* Spinners */
.spinner {
    width: 1.25rem;
    height: 1.25rem;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

.hidden {
    display: none;
}