/* ===== VARIABLES MODERNES ===== */
:root {
    /* Palette de couleurs modernes */
    --primary-50: #f0f9ff;
    --primary-100: #e0f2fe;
    --primary-500: #27ae60;
    --primary-600: #27ae60;
    --primary-700: #27ae60;
    --primary-900: #14532d;
    
    --secondary-500: #f59e0b;
    --success-500: #10b981;
    --danger-500: #ef4444;
    --warning-500: #f59e0b;
    
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    
    /* Effets modernes */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-md: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 20px 25px -5px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 25px 50px -12px rgb(0 0 0 / 0.25);
    
    --blur-sm: blur(4px);
    --blur-md: blur(8px);
    --blur-lg: blur(16px);
    
    /* Espacements mobiles */
    --space-xs: 0.5rem;
    --space-sm: 0.75rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    
    /* Bordures */
    --radius-sm: 0.5rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.25rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
    
    /* Safe areas */
    --sat: env(safe-area-inset-top);
    --sab: env(safe-area-inset-bottom);
    --sal: env(safe-area-inset-left);
    --sar: env(safe-area-inset-right);
}

/* ===== RESET MOBILE-FIRST ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

html {
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Inter', 'Segoe UI', system-ui, sans-serif;
    background: linear-gradient(135deg, var(--primary-900) 0%, #219150 100%);
    color: var(--gray-900);
    line-height: 1.5;
    min-height: 100vh;
    min-height: -webkit-fill-available;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
    padding-top: var(--sat);
    padding-bottom: var(--sab);
}

/* ===== NAVIGATION MOBILE-FIRST ===== */
.vlsa-nav {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: var(--blur-lg);
    -webkit-backdrop-filter: var(--blur-lg);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    padding: var(--space-sm) var(--space-md);
    padding-top: calc(var(--space-sm) + var(--sat));
    position: sticky;
    top: 0;
    z-index: 50;
    box-shadow: var(--shadow-sm);
}

.nav-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-sm);
}

.brand {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    text-decoration: none;
}

.brand-icon {
    width: 44px;
    height: 44px;
    background: linear-gradient(135deg, var(--primary-500), var(--primary-700));
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.25rem;
    box-shadow: var(--shadow);
}

.brand-text {
    display: flex;
    flex-direction: column;
}

.brand-name {
    font-size: 1.25rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-600), var(--primary-800));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.025em;
}

.brand-tagline {
    font-size: 0.75rem;
    color: var(--gray-500);
    font-weight: 500;
    letter-spacing: -0.01em;
}

.lang-selector {
    background: rgba(255, 255, 255, 0.9);
    border: 1.5px solid var(--gray-200);
    border-radius: var(--radius-full);
    padding: 0.5rem 1rem 0.5rem 0.75rem;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--gray-700);
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%236b7280'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.5rem center;
    background-size: 1rem;
    min-width: 120px;
    transition: var(--transition-fast);
}

.lang-selector:focus {
    outline: none;
    border-color: var(--primary-500);
    box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.1);
}

/* ===== CONTAINER PRINCIPAL ===== */
.main-container {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-lg) var(--space-md);
    width: 100%;
}

/* ===== CARTE DE CONNEXION MODERNE ===== */
.login-card {
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: var(--blur-lg);
    -webkit-backdrop-filter: var(--blur-lg);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-xl);
    width: 100%;
    max-width: 440px;
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.3);
    animation: slideUp 0.6s var(--transition) forwards;
    opacity: 0;
    transform: translateY(20px);
}

@keyframes slideUp {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.card-header {
    background: linear-gradient(135deg, var(--primary-500), var(--primary-700));
    padding: var(--space-xl) var(--space-lg);
    text-align: center;
    color: white;
    position: relative;
    overflow: hidden;
}

.card-header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(45deg, transparent 30%, rgba(255,255,255,0.1) 50%, transparent 70%);
    animation: shine 3s infinite;
}

@keyframes shine {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

.card-header h2 {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    letter-spacing: -0.025em;
}

.card-header p {
    opacity: 0.9;
    font-size: 0.9375rem;
    font-weight: 400;
}

/* ===== FORMULAIRE MODERNE ===== */
.login-form {
    padding: var(--space-xl) var(--space-lg);
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

.form-group {
    position: relative;
}

.form-group label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--gray-700);
}

.form-group input {
    width: 100%;
    padding: 1rem 1rem 1rem 3rem;
    background: var(--gray-50);
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-lg);
    font-size: 1rem;
    font-weight: 500;
    color: var(--gray-900);
    transition: var(--transition-fast);
    -webkit-appearance: none;
    appearance: none;
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary-500);
    background: white;
    box-shadow: 0 0 0 4px rgba(14, 165, 233, 0.1);
}

.form-group input::placeholder {
    color: var(--gray-400);
    font-weight: 400;
}

.form-group i.fas {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(50%);
    color: var(--gray-400);
    font-size: 1.125rem;
    transition: var(--transition-fast);
}

.form-group input:focus + i.fas {
    color: var(--primary-500);
}

/* ===== BOUTONS MODERNES ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.625rem;
    padding: 1rem 1.5rem;
    border: none;
    border-radius: var(--radius-lg);
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
    min-height: 3.5rem;
    user-select: none;
    -webkit-user-select: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-500), var(--primary-600));
    color: white;
    box-shadow: 0 4px 15px rgba(14, 165, 233, 0.3);
}

.btn-primary:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(14, 165, 233, 0.4);
}

.btn-primary:active:not(:disabled) {
    transform: translateY(0);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.btn-secondary {
    background: white;
    color: var(--primary-600);
    border: 2px solid var(--primary-200);
    box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
    background: var(--primary-50);
    border-color: var(--primary-300);
    transform: translateY(-1px);
}

/* Ripple effect */
.btn-ripple {
    position: absolute;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.7);
    transform: scale(0);
    animation: ripple 0.6s linear;
    pointer-events: none;
}

@keyframes ripple {
    to {
        transform: scale(4);
        opacity: 0;
    }
}

/* ===== LOADER MODERNE ===== */
.loader {
    display: none;
    width: 1.25rem;
    height: 1.25rem;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 0.8s linear infinite;
}

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

.btn.loading .loader {
    display: block;
}

.btn.loading span {
    opacity: 0.8;
}

/* ===== MOT DE PASSE OUBLIÉ ===== */
.forgot-password {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--primary-600);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    transition: var(--transition-fast);
    padding: 0.5rem;
    border-radius: var(--radius-sm);
}

.forgot-password:hover {
    color: var(--primary-700);
    background: var(--primary-50);
}

/* ===== INSCRIPTION ===== */
.register-link {
    text-align: center;
    padding-top: var(--space-lg);
    border-top: 1px solid var(--gray-200);
    margin-top: var(--space-lg);
}

.register-link p {
    color: var(--gray-600);
    font-size: 0.9375rem;
    margin-bottom: var(--space-md);
}

/* ===== INDICATEUR DE FORCE ===== */
.password-strength {
    height: 4px;
    background: var(--gray-200);
    border-radius: 2px;
    margin-top: 0.5rem;
    overflow: hidden;
    position: relative;
}

.strength-bar {
    height: 100%;
    width: 0%;
    border-radius: 2px;
    transition: width 0.3s ease;
    background: var(--danger-500);
}

.strength-bar.weak {
    width: 33%;
    background: var(--danger-500);
}

.strength-bar.medium {
    width: 66%;
    background: var(--warning-500);
}

.strength-bar.strong {
    width: 100%;
    background: var(--success-500);
}

/* ===== TOAST MODERNE ===== */
.toast {
    position: fixed;
    bottom: var(--space-xl);
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--gray-800);
    color: white;
    padding: var(--space-md) var(--space-lg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    max-width: calc(100vw - 2rem);
    z-index: 1000;
    opacity: 0;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    backdrop-filter: var(--blur-md);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

.toast.success {
    background: linear-gradient(135deg, var(--success-500), #059669);
}

.toast.error {
    background: linear-gradient(135deg, var(--danger-500), #dc2626);
}

.toast.warning {
    background: linear-gradient(135deg, var(--warning-500), #d97706);
}

/* ===== FOOTER MOBILE ===== */
.vlsa-footer {
    background: var(--gray-900);
    color: white;
    padding: var(--space-lg) var(--space-md);
    padding-bottom: calc(var(--space-lg) + var(--sab));
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-sm);
    margin-bottom: var(--space-lg);
}

.footer-links a {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--gray-300);
    text-decoration: none;
    font-size: 0.875rem;
    padding: 0.5rem;
    border-radius: var(--radius-sm);
    transition: var(--transition-fast);
}

.footer-links a:hover {
    color: white;
    background: rgba(255, 255, 255, 0.1);
}

.copyright {
    font-size: 0.75rem;
    color: var(--gray-400);
    text-align: center;
    line-height: 1.6;
}

/* ===== DARK MODE ===== */
@media (prefers-color-scheme: dark) {
    .vlsa-nav {
        background: rgba(15, 23, 42, 0.95);
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    }
    
    .login-card {
        background: rgba(15, 23, 42, 0.95);
        border: 1px solid rgba(255, 255, 255, 0.1);
        color: var(--gray-100);
    }
    
    .form-group input {
        background: rgba(255, 255, 255, 0.05);
        border-color: rgba(255, 255, 255, 0.1);
        color: var(--gray-100);
    }
    
    .form-group label {
        color: var(--gray-300);
    }
    
    .btn-secondary {
        background: rgba(255, 255, 255, 0.05);
        color: var(--primary-300);
        border-color: rgba(255, 255, 255, 0.1);
    }
    
    .btn-secondary:hover {
        background: rgba(255, 255, 255, 0.1);
    }
    
    .register-link {
        border-top-color: rgba(255, 255, 255, 0.1);
    }
    
    .register-link p {
        color: var(--gray-400);
    }
}

/* ===== RESPONSIVE ADAPTATIONS ===== */

/* Petits mobiles */
@media (max-width: 374px) {
    .brand-name {
        font-size: 1.125rem;
    }
    
    .brand-icon {
        width: 40px;
        height: 40px;
        font-size: 1.125rem;
    }
    
    .login-form {
        padding: var(--space-lg) var(--space-md);
    }
    
    .btn {
        min-height: 3rem;
        padding: 0.875rem 1.25rem;
    }
}

/* Paysage mobile */
@media (orientation: landscape) and (max-height: 600px) {
    .main-container {
        padding: var(--space-sm);
        align-items: flex-start;
        overflow-y: auto;
    }
    
    .login-card {
        margin: var(--space-sm) auto;
        max-height: 90vh;
        overflow-y: auto;
    }
    
    .card-header {
        padding: var(--space-lg) var(--space-md);
    }
    
    .login-form {
        padding: var(--space-md);
        gap: var(--space-md);
    }
    
    .form-group input {
        padding: 0.75rem 0.75rem 0.75rem 2.75rem;
    }
}

/* Tablettes */
@media (min-width: 768px) {
    .vlsa-nav {
        padding: var(--space-md) var(--space-xl);
        padding-top: calc(var(--space-md) + var(--sat));
    }
    
    .login-card {
        max-width: 480px;
    }
    
    .card-header {
        padding: var(--space-2xl) var(--space-xl);
    }
    
    .login-form {
        padding: var(--space-2xl) var(--space-xl);
    }
    
    .footer-links {
        grid-template-columns: repeat(4, auto);
        justify-content: center;
        gap: var(--space-xl);
    }
}

/* Desktop */
@media (min-width: 1024px) {
    .login-card {
        max-width: 440px;
    }
    
    .brand-name {
        font-size: 1.375rem;
    }
}

/* Très grands écrans */
@media (min-width: 1440px) {
    .vlsa-nav,
    .footer-content {
        max-width: 1400px;
    }
}

/* ===== PWA FULLSCREEN ===== */
@media (display-mode: standalone) {
    .vlsa-nav {
        padding-top: calc(var(--space-lg) + var(--sat));
    }
    
    body {
        padding-top: var(--sat);
    }
}

/* ===== ACCESSIBILITÉ ===== */
@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;
    }
}

:focus-visible {
    outline: 3px solid var(--primary-500);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
}

/* Touch targets minimum */
@media (max-width: 768px) {
    .btn,
    .footer-links a,
    .forgot-password {
        min-height: 44px;
        min-width: 44px;
    }
}