/* --- DESIGN SYSTEM ULTRA-PREMIUM V2 --- */
:root {
    --brand-accent: #8b5cf6; /* Violet électrique */
    --brand-accent-hover: #7c3aed;
    --brand-secondary: #3b82f6; /* Bleu cloud */
    --brand-success: #10b981;
    --brand-error: #ef4444;
    
    --bg-dark: #09090b;
    --bg-panel: rgba(24, 24, 27, 0.6);
    --border-subtle: rgba(255, 255, 255, 0.1);
    --border-focus: rgba(139, 92, 246, 0.3);
    
    --text-primary: #fafafa;
    --text-secondary: #a1a1aa;
    --text-muted: #71717a;
    
    --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
    --transition-smooth: 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    --transition-fast: 0.15s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
    scroll-behavior: smooth;
}

body {
    background-color: var(--bg-dark);
    color: var(--text-primary);
    font-family: var(--font-sans);
    overflow: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* --- SPLIT LAYOUT (GRID) --- */
.split-layout {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    min-height: 100vh;
}

/* =========================================
   SECTION GAUCHE : BRANDING & ANIMATIONS
========================================= */
.brand-section {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 4rem;
    overflow: hidden;
    border-right: 1px solid var(--border-subtle);
    background: radial-gradient(circle at top left, #18181b, var(--bg-dark));
}

/* Formes floutées animées (Blobs) - Optimisées */
.animated-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 0;
    filter: blur(100px);
    opacity: 0.5;
    will-change: transform;
}

.blob {
    position: absolute;
    border-radius: 50%;
    animation: float 25s infinite ease-in-out alternate;
}

.blob-1 {
    width: 400px;
    height: 400px;
    background: var(--brand-accent);
    top: -10%;
    left: 10%;
}

.blob-2 {
    width: 500px;
    height: 500px;
    background: var(--brand-secondary);
    bottom: -20%;
    right: -10%;
    animation-delay: -7s;
}

@keyframes float {
    0% {
        transform: translate(0, 0) scale(1);
    }
    100% {
        transform: translate(80px, 40px) scale(1.15);
    }
}

/* Glassmorphism Panel */
.glass-panel {
    position: relative;
    z-index: 1;
    background: rgba(255, 255, 255, 0.02);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border: 1px solid var(--border-subtle);
    border-radius: 24px;
    padding: 3rem;
    max-width: 520px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5),
                inset 0 1px 0 0 rgba(255, 255, 255, 0.05);
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 2.5rem;
    color: var(--text-primary);
    letter-spacing: -0.5px;
}

.logo svg {
    color: var(--brand-accent);
    flex-shrink: 0;
}

.glass-panel h1 {
    font-size: 2.75rem;
    line-height: 1.2;
    margin-bottom: 1rem;
    font-weight: 700;
    letter-spacing: -1px;
    background: linear-gradient(to right, #fff 0%, #a1a1aa 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.glass-panel p {
    font-size: 1.0625rem;
    color: var(--text-secondary);
    line-height: 1.7;
    font-weight: 400;
}

/* =========================================
   SECTION DROITE : FORMULAIRE
========================================= */
.auth-section {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
    background-color: var(--bg-dark);
    position: relative;
}

.auth-wrapper {
    width: 100%;
    max-width: 400px;
    animation: slideUp 0.5s var(--transition-smooth);
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.auth-header {
    margin-bottom: 2.5rem;
}

.auth-header h1 {
    font-size: 1.875rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    letter-spacing: -0.5px;
}

.auth-header p {
    color: var(--text-secondary);
    font-size: 0.9375rem;
}

/* ========================================= 
   ERROR & SUCCESS STATES
========================================= */
.form-error {
    display: none;
    padding: 0.75rem 1rem;
    background-color: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    border-radius: 10px;
    color: #fca5a5;
    font-size: 0.875rem;
    margin-bottom: 1.5rem;
    animation: slideDown 0.3s var(--transition-smooth);
}

.form-error.show {
    display: block;
}

.success-message {
    display: none;
    padding: 1rem;
    background-color: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.3);
    border-radius: 10px;
    color: #86efac;
    font-size: 0.9375rem;
    margin-top: 1.5rem;
    align-items: center;
    gap: 10px;
    animation: slideDown 0.3s var(--transition-smooth);
}

.success-message.show {
    display: flex;
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* OAuth Button */
.oauth-group {
    margin-bottom: 2rem;
}

.btn-oauth {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 0.875rem 1rem;
    background-color: transparent;
    border: 1.5px solid var(--border-subtle);
    border-radius: 12px;
    color: var(--text-primary);
    font-size: 0.9375rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition-smooth);
    position: relative;
    overflow: hidden;
}

.btn-oauth::before {
    content: "";
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transition: var(--transition-smooth);
}

.btn-oauth:hover {
    background-color: rgba(255, 255, 255, 0.05);
    border-color: var(--border-subtle);
    transform: translateY(-1px);
}

.btn-oauth:hover::before {
    left: 100%;
}

.btn-oauth:focus-visible {
    outline: 2px solid var(--brand-accent);
    outline-offset: 2px;
}

.btn-oauth:active {
    transform: translateY(0);
}

/* Divider */
.divider {
    display: flex;
    align-items: center;
    margin: 2rem 0;
    color: var(--text-muted);
    font-size: 0.8125rem;
    font-weight: 500;
}

.divider::before,
.divider::after {
    content: "";
    flex: 1;
    height: 1px;
    background: linear-gradient(to right, var(--border-subtle), transparent);
}

.divider::after {
    background: linear-gradient(to left, var(--border-subtle), transparent);
}

.divider span {
    padding: 0 1rem;
}

/* ========================================= 
   FLOATING LABELS & INPUTS
========================================= */
.floating-input-group {
    position: relative;
    margin-bottom: 1.5rem;
}

.floating-input-group input {
    width: 100%;
    padding: 1.125rem 1rem 0.5rem;
    background-color: rgba(255, 255, 255, 0.03);
    border: 1.5px solid var(--border-subtle);
    border-radius: 12px;
    color: var(--text-primary);
    font-size: 0.9375rem;
    font-family: inherit;
    transition: var(--transition-smooth);
    -webkit-autofill-selected-text-color: var(--text-primary);
}

.floating-input-group input::placeholder {
    color: transparent;
}

.floating-input-group input:hover {
    background-color: rgba(255, 255, 255, 0.04);
    border-color: rgba(255, 255, 255, 0.15);
}

.floating-input-group input:focus {
    outline: none;
    background-color: rgba(255, 255, 255, 0.06);
    border-color: var(--brand-accent);
    box-shadow: 0 0 0 3px var(--border-focus);
}

.floating-input-group input:invalid:not(:placeholder-shown) {
    border-color: var(--brand-error);
}

.floating-input-group input:invalid:focus {
    box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.2);
}

/* Label Animation */
.floating-input-group label {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-secondary);
    pointer-events: none;
    transition: var(--transition-fast);
    font-size: 0.9375rem;
    font-weight: 500;
}

.floating-input-group input:focus ~ label,
.floating-input-group input:not(:placeholder-shown) ~ label {
    top: 0.625rem;
    font-size: 0.75rem;
    color: var(--brand-accent);
    font-weight: 600;
}

.floating-input-group input:invalid:not(:placeholder-shown) ~ label {
    color: var(--brand-error);
}

/* Input Hint */
.input-hint {
    display: block;
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 0.25rem;
    height: 1rem;
}

.floating-input-group input:invalid:not(:placeholder-shown) ~ .input-hint {
    color: var(--brand-error);
}

/* Password Toggle Button */
.toggle-password {
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    width: 36px;
    height: 36px;
    background: transparent;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition-fast);
    z-index: 10;
}

.toggle-password:hover {
    color: var(--text-primary);
}

.toggle-password:focus-visible {
    outline: 2px solid var(--brand-accent);
    outline-offset: 2px;
}

/* ========================================= 
   CHECKBOX CUSTOM
========================================= */
.remember-me {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    user-select: none;
    transition: var(--transition-fast);
}

.remember-me input[type="checkbox"] {
    display: none;
}

.checkmark {
    width: 20px;
    height: 20px;
    border: 1.5px solid var(--border-subtle);
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition-fast);
    flex-shrink: 0;
}

.remember-me input[type="checkbox"]:checked ~ .checkmark {
    background: linear-gradient(135deg, var(--brand-accent), var(--brand-secondary));
    border-color: transparent;
}

.remember-me input[type="checkbox"]:checked ~ .checkmark::after {
    content: "✓";
    color: white;
    font-size: 0.75rem;
    font-weight: 700;
}

.remember-me input[type="checkbox"]:focus-visible ~ .checkmark {
    outline: 2px solid var(--brand-accent);
    outline-offset: 2px;
}

.remember-me:hover .checkmark {
    border-color: var(--brand-accent);
}

/* ========================================= 
   FORM OPTIONS & LINKS
========================================= */
.form-options {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    font-size: 0.875rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.remember-me span:last-child {
    color: var(--text-primary);
    font-weight: 500;
}

.forgot-link {
    color: var(--brand-accent);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition-fast);
    position: relative;
}

.forgot-link::after {
    content: "";
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 1.5px;
    background: var(--brand-accent);
    transition: var(--transition-fast);
}

.forgot-link:hover {
    color: var(--brand-accent-hover);
}

.forgot-link:hover::after {
    width: 100%;
}

.forgot-link:focus-visible {
    outline: 2px solid var(--brand-accent);
    outline-offset: 4px;
}

/* ========================================= 
   PRIMARY BUTTON
========================================= */
.btn-primary {
    width: 100%;
    padding: 1rem;
    background: linear-gradient(135deg, var(--brand-accent) 0%, var(--brand-secondary) 100%);
    color: white;
    border: none;
    border-radius: 12px;
    font-size: 0.9375rem;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(139, 92, 246, 0.3);
    transition: var(--transition-smooth);
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.btn-primary::before {
    content: "";
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: var(--transition-smooth);
    z-index: 0;
}

.btn-text {
    position: relative;
    z-index: 1;
}

.btn-loader {
    position: relative;
    z-index: 1;
    display: flex;
    gap: 4px;
    opacity: 0;
    transform: scale(0.8);
    transition: var(--transition-smooth);
}

.btn-loader span {
    width: 4px;
    height: 4px;
    border-radius: 50%;
    background: white;
    animation: bounce 1.4s infinite;
}

.btn-loader span:nth-child(2) {
    animation-delay: 0.2s;
}

.btn-loader span:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes bounce {
    0%, 100% {
        opacity: 0.3;
        transform: translateY(0);
    }
    50% {
        opacity: 1;
        transform: translateY(-8px);
    }
}

.btn-primary:hover:not(:disabled) {
    box-shadow: 0 8px 25px rgba(139, 92, 246, 0.4);
    transform: translateY(-2px);
}

.btn-primary:hover:not(:disabled)::before {
    left: 100%;
}

.btn-primary:focus-visible {
    outline: 2px solid var(--brand-accent);
    outline-offset: 2px;
}

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

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

.btn-primary.loading .btn-text {
    opacity: 0;
    transform: scale(0.8);
}

.btn-primary.loading .btn-loader {
    opacity: 1;
    transform: scale(1);
}

/* ========================================= 
   SIGNUP PROMPT
========================================= */
.signup-prompt {
    text-align: center;
    margin-top: 2rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.signup-prompt a {
    color: var(--brand-accent);
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition-fast);
    position: relative;
}

.signup-prompt a::after {
    content: "";
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 1.5px;
    background: var(--brand-accent);
    transition: var(--transition-fast);
}

.signup-prompt a:hover {
    color: var(--brand-accent-hover);
}

.signup-prompt a:hover::after {
    width: 100%;
}

.signup-prompt a:focus-visible {
    outline: 2px solid var(--brand-accent);
    outline-offset: 4px;
}

/* ========================================= 
   RESPONSIVE DESIGN
========================================= */
@media (max-width: 968px) {
    .split-layout {
        grid-template-columns: 1fr;
    }
    
    .brand-section {
        display: none;
    }
    
    .auth-section {
        padding: 2rem 1rem;
    }
    
    .auth-wrapper {
        max-width: 100%;
    }
    
    .glass-panel {
        padding: 2.5rem;
    }
    
    .glass-panel h1 {
        font-size: 2rem;
    }
}

@media (max-width: 480px) {
    .auth-section {
        padding: 1.5rem 1rem;
    }
    
    .auth-wrapper {
        max-width: 100%;
    }
    
    .auth-header h1 {
        font-size: 1.5rem;
    }
    
    .form-options {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.75rem;
    }
    
    .forgot-link {
        width: 100%;
        text-align: right;
    }
    
    .btn-primary {
        padding: 0.9rem;
        font-size: 0.875rem;
    }
}

/* ========================================= 
   DARK MODE & CONTRAST
========================================= */
@media (prefers-contrast: more) {
    :root {
        --border-subtle: rgba(255, 255, 255, 0.2);
    }
    
    .btn-primary {
        box-shadow: 0 2px 8px rgba(139, 92, 246, 0.5);
    }
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* ========================================= 
   PRINT STYLES
========================================= */
@media print {
    .animated-bg,
    .blob {
        display: none;
    }
}