/* === VARIABLES CSS POUR LES MODES JOUR/NUIT === */
:root {
    /* Mode Nuit (par défaut) */
    --bg-primary: #0f0f23;
    --bg-secondary: #1a1a2e;
    --bg-tertiary: #16213e;
    --bg-quaternary: #0f3460;
    --bg-quinary: #1e3a8a;
    --text-primary: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.8);
    --text-muted: rgba(255, 255, 255, 0.6);
    --accent-primary: #8b5cf6;
    --accent-secondary: #6366f1;
    --border-color: rgba(139, 92, 246, 0.2);
    --card-bg: rgba(255, 255, 255, 0.05);
    --nav-bg: rgba(15, 15, 35, 0.95);
    --shadow-color: rgba(0, 0, 0, 0.3);
    --orb-color-1: rgba(139, 92, 246, 0.4);
    --orb-color-2: rgba(6, 182, 212, 0.2);
    --orb-color-3: rgba(16, 185, 129, 0.4);
    --orb-color-4: rgba(245, 158, 11, 0.2);
    --orb-color-5: rgba(249, 115, 22, 0.4);
    --orb-color-6: rgba(236, 72, 153, 0.2);
}

/* Mode Jour */
[data-theme="day"] {
    --bg-primary: #3b82f6;
    --bg-secondary: #60a5fa;
    --bg-tertiary: #93c5fd;
    --bg-quaternary: #3b82f6;
    --bg-quinary: #1d4ed8;
    --text-primary: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.9);
    --text-muted: rgba(255, 255, 255, 0.7);
    --accent-primary: #1e40af;
    --accent-secondary: #1e3a8a;
    --border-color: rgba(255, 255, 255, 0.3);
    --card-bg: rgba(255, 255, 255, 0.15);
    --nav-bg: rgba(59, 130, 246, 0.95);
    --shadow-color: rgba(0, 0, 0, 0.2);
    --orb-color-1: rgba(255, 255, 255, 0.3);
    --orb-color-2: rgba(30, 64, 175, 0.4);
    --orb-color-3: rgba(255, 255, 255, 0.2);
    --orb-color-4: rgba(29, 78, 216, 0.3);
    --orb-color-5: rgba(255, 255, 255, 0.4);
    --orb-color-6: rgba(30, 58, 138, 0.3);
}

/* === APPLICATION DES VARIABLES CSS === */
html,
body {
    margin: 0;
    padding: 0;
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 25%, var(--bg-tertiary) 50%, var(--bg-quaternary) 75%, var(--bg-quinary) 100%);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    overflow-x: hidden;
    font-weight: 400;
    min-height: 100vh;
    transition: background 0.6s ease, color 0.6s ease;
}

/* === COMPORTEMENT DE SCROLL FLUIDE === */
html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    overflow-x: hidden;
    scroll-behavior: smooth;
}

/* === TRANSITIONS ULTRA-FLUIDES === */
* {
    box-sizing: border-box;
}

/* === ANIMATIONS D'ENTRÉE FLUIDES === */
.fade-in-up {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.fade-in-up.active {
    opacity: 1;
    transform: translateY(0);
}

/* === TRANSITIONS DES ÉLÉMENTS INTERACTIFS === */
a, button, .nav-link {
    transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

/* === PREFERENCES DE MOUVEMENT === */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* === ILLUSTRATIONS MODE JOUR/NUIT === */
.illustration-day {
    display: none !important;
    opacity: 0;
    transition: opacity 0.6s ease;
}

.illustration-night {
    display: block !important;
    opacity: 1;
    transition: opacity 0.6s ease;
}

[data-theme="day"] .illustration-day {
    display: block !important;
    opacity: 1;
}

[data-theme="day"] .illustration-night {
    display: none !important;
    opacity: 0;
}