/**
 * NextStep Authentication Styles
 * Login, Signup, Password Reset with Real-time Validation & Progress Indicators
 * WCAG 2.1 AA Compliant
 */

/* ========================================
   AUTHENTICATION CONTAINER
   ======================================== */

.auth-container {
    min-height: calc(100vh - 80px);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-8) var(--space-4);
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    position: relative;
}

.auth-container::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 20% 50%, rgba(0, 217, 163, 0.05) 0%, transparent 50%),
                radial-gradient(circle at 80% 80%, rgba(102, 126, 234, 0.05) 0%, transparent 50%);
    pointer-events: none;
    z-index: 0;
}

.auth-container > .container {
    position: relative;
    z-index: 1;
}

/* ========================================
   AUTH CARD
   ======================================== */

.auth-card {
    background: var(--surface-elevated);
    border-radius: var(--border-radius-2xl);
    box-shadow: var(--shadow-xl);
    border: 1px solid var(--border-color);
    overflow: hidden;
    max-width: 480px;
    width: 100%;
    animation: fadeInUp 0.6s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.auth-header {
    text-align: center;
    padding: var(--space-8) var(--space-6) var(--space-6);
    background: var(--primary-gradient);
    color: white;
    position: relative;
    overflow: hidden;
}

.auth-header::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
    animation: pulse 3s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); opacity: 0.5; }
    50% { transform: scale(1.1); opacity: 0.8; }
}

.auth-header h1 {
    color: white;
    font-size: clamp(1.75rem, 4vw, 2.25rem);
    font-weight: var(--font-extrabold);
    margin-bottom: var(--space-2);
    position: relative;
    z-index: 1;
}

.auth-header p {
    color: rgba(255, 255, 255, 0.95);
    margin: 0;
    font-size: var(--text-base);
    position: relative;
    z-index: 1;
}

.auth-body {
    padding: var(--space-8) var(--space-6);
}

/* ========================================
   PROGRESS INDICATOR (Multi-step forms)
   ======================================== */

.progress-steps {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-8);
    position: relative;
    padding: 0 var(--space-4);
}

.progress-steps::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--border-color);
    z-index: 0;
    transform: translateY(-50%);
}

.progress-step {
    position: relative;
    z-index: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-2);
    flex: 1;
}

.progress-step-circle {
    width: 40px;
    height: 40px;
    border-radius: var(--border-radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: var(--font-bold);
    font-size: var(--text-sm);
    background: var(--surface);
    border: 2px solid var(--border-color);
    color: var(--text-secondary);
    transition: all var(--transition-base);
}

.progress-step.active .progress-step-circle {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
    box-shadow: 0 0 0 4px var(--primary-light);
}

.progress-step.completed .progress-step-circle {
    background: var(--success);
    border-color: var(--success);
    color: white;
}

.progress-step.completed .progress-step-circle::after {
    content: '✓';
    font-size: var(--text-lg);
}

.progress-step-label {
    font-size: var(--text-xs);
    color: var(--text-secondary);
    text-align: center;
    font-weight: var(--font-medium);
}

.progress-step.active .progress-step-label {
    color: var(--primary);
    font-weight: var(--font-semibold);
}

.progress-step.completed .progress-step-label {
    color: var(--success);
}

/* ========================================
   FORM GROUPS & INPUTS
   ======================================== */

.form-group {
    margin-bottom: var(--space-6);
    position: relative;
}

.form-label {
    display: block;
    font-weight: var(--font-semibold);
    color: var(--text-primary);
    margin-bottom: var(--space-2);
    font-size: var(--text-sm);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.form-label .required {
    color: var(--error);
    margin-left: 2px;
}

.form-control {
    width: 100%;
    padding: var(--space-4) var(--space-4);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius-md);
    font-size: var(--text-base);
    transition: all var(--transition-base);
    background-color: var(--background);
    color: var(--text-primary);
    font-family: var(--font-sans);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.form-control::placeholder {
    color: var(--text-tertiary);
    opacity: 0.6;
}

/* Input States */
.form-control.valid {
    border-color: var(--success);
    background-image: url("data:image/svg+xml,%3Csvg width='20' height='20' fill='%2310b981' viewBox='0 0 24 24'%3E%3Cpath d='M9 16.17L4.83 12l-1.42 1.41L9 19 21 7l-1.41-1.41z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right var(--space-3) center;
    background-size: 20px;
    padding-right: var(--space-12);
}

.form-control.invalid {
    border-color: var(--error);
    background-image: url("data:image/svg+xml,%3Csvg width='20' height='20' fill='%23ef4444' viewBox='0 0 24 24'%3E%3Cpath d='M12 2C6.48 2 2 6.48 2 12s4.48 10 10 10 10-4.48 10-10S17.52 2 12 2zm1 15h-2v-2h2v2zm0-4h-2V7h2v6z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right var(--space-3) center;
    background-size: 20px;
    padding-right: var(--space-12);
}

.form-control:disabled {
    background-color: var(--surface);
    cursor: not-allowed;
    opacity: 0.6;
}

/* ========================================
   REAL-TIME VALIDATION FEEDBACK
   ======================================== */

.validation-feedback {
    display: flex;
    align-items: flex-start;
    gap: var(--space-2);
    margin-top: var(--space-2);
    font-size: var(--text-sm);
    line-height: 1.5;
    animation: slideDown 0.3s ease-out;
}

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

.validation-feedback.valid {
    color: var(--success);
}

.validation-feedback.invalid {
    color: var(--error);
}

.validation-feedback.info {
    color: var(--text-secondary);
}

.validation-icon {
    flex-shrink: 0;
    width: 16px;
    height: 16px;
    margin-top: 2px;
}

.validation-message {
    flex: 1;
}

/* Password Strength Indicator */
.password-strength-container {
    margin-top: var(--space-3);
}

.password-strength-bar {
    height: 4px;
    background-color: var(--border-color);
    border-radius: var(--border-radius-full);
    overflow: hidden;
    margin-bottom: var(--space-2);
}

.password-strength-fill {
    height: 100%;
    width: 0%;
    transition: all var(--transition-base);
    border-radius: var(--border-radius-full);
}

.password-strength-fill.weak {
    width: 33%;
    background-color: var(--error);
}

.password-strength-fill.medium {
    width: 66%;
    background-color: var(--warning);
}

.password-strength-fill.strong {
    width: 100%;
    background-color: var(--success);
}

.password-requirements {
    list-style: none;
    padding: 0;
    margin: 0;
    font-size: var(--text-xs);
    color: var(--text-secondary);
}

.password-requirements li {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    margin-bottom: var(--space-1);
    transition: color var(--transition-base);
}

.password-requirements li.valid {
    color: var(--success);
}

.password-requirements li.invalid {
    color: var(--text-tertiary);
}

.password-requirements li::before {
    content: '○';
    font-size: var(--text-sm);
    flex-shrink: 0;
}

.password-requirements li.valid::before {
    content: '✓';
    color: var(--success);
}

/* ========================================
   SOCIAL LOGIN BUTTONS
   ======================================== */

.social-login-section {
    margin-bottom: var(--space-6);
}

.social-login-divider {
    display: flex;
    align-items: center;
    text-align: center;
    margin: var(--space-6) 0;
    color: var(--text-tertiary);
    font-size: var(--text-sm);
}

.social-login-divider::before,
.social-login-divider::after {
    content: '';
    flex: 1;
    border-bottom: 1px solid var(--border-color);
}

.social-login-divider span {
    padding: 0 var(--space-4);
}

.social-buttons {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.btn-social {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-3);
    padding: var(--space-4) var(--space-6);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    background-color: var(--background);
    color: var(--text-primary);
    font-weight: var(--font-semibold);
    font-size: var(--text-base);
    transition: all var(--transition-base);
    cursor: pointer;
    text-decoration: none;
    min-height: 52px;
    position: relative;
    overflow: hidden;
}

.btn-social::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(0, 0, 0, 0.05);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn-social:hover::before {
    width: 300px;
    height: 300px;
}

.btn-social:hover {
    border-color: var(--primary);
    background-color: var(--primary-light);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

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

.btn-social-icon {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
}

.btn-social-google {
    border-color: #4285F4;
}

.btn-social-google:hover {
    border-color: #4285F4;
    background-color: rgba(66, 133, 244, 0.1);
}

.btn-social-linkedin {
    border-color: #0077B5;
}

.btn-social-linkedin:hover {
    border-color: #0077B5;
    background-color: rgba(0, 119, 181, 0.1);
}

/* ========================================
   FORM ACTIONS
   ======================================== */

.form-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-6);
    flex-wrap: wrap;
    gap: var(--space-3);
}

.form-check {
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.form-check-input {
    width: 20px;
    height: 20px;
    cursor: pointer;
    accent-color: var(--primary);
}

.form-check-label {
    color: var(--text-secondary);
    font-size: var(--text-sm);
    cursor: pointer;
    user-select: none;
}

.forgot-password-link {
    color: var(--primary);
    text-decoration: none;
    font-size: var(--text-sm);
    font-weight: var(--font-semibold);
    transition: color var(--transition-base);
}

.forgot-password-link:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

/* ========================================
   SUBMIT BUTTON
   ======================================== */

.btn-submit {
    width: 100%;
    padding: var(--space-4) var(--space-6);
    background: var(--primary-gradient);
    color: white;
    border: none;
    border-radius: var(--border-radius-lg);
    font-size: var(--text-base);
    font-weight: var(--font-bold);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    cursor: pointer;
    transition: all var(--transition-base);
    min-height: 52px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    position: relative;
    overflow: hidden;
}

.btn-submit::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn-submit:hover::before {
    width: 300px;
    height: 300px;
}

.btn-submit:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

.btn-submit:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.btn-submit-loading {
    pointer-events: none;
}

.btn-submit-loading .spinner {
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

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

/* ========================================
   ALERTS & MESSAGES
   ======================================== */

.alert {
    padding: var(--space-4);
    border-radius: var(--border-radius-md);
    margin-bottom: var(--space-5);
    display: flex;
    align-items: flex-start;
    gap: var(--space-3);
    animation: slideDown 0.3s ease-out;
}

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

.alert-success {
    background-color: rgba(16, 185, 129, 0.1);
    border: 1px solid var(--success);
    color: var(--success);
}

.alert-info {
    background-color: rgba(59, 130, 246, 0.1);
    border: 1px solid var(--info);
    color: var(--info);
}

.alert-icon {
    flex-shrink: 0;
    width: 20px;
    height: 20px;
}

/* ========================================
   TRUST BADGES
   ======================================== */

.trust-badges {
    display: flex;
    justify-content: center;
    gap: var(--space-6);
    margin-top: var(--space-6);
    flex-wrap: wrap;
}

.trust-badge {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    color: var(--text-tertiary);
    font-size: var(--text-xs);
}

.trust-badge-icon {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
}

/* ========================================
   AUTH FOOTER
   ======================================== */

.auth-footer {
    text-align: center;
    padding: var(--space-6);
    background-color: var(--surface);
    border-top: 1px solid var(--border-color);
}

.auth-footer p {
    margin: 0;
    color: var(--text-secondary);
    font-size: var(--text-sm);
}

.auth-footer a {
    color: var(--primary);
    font-weight: var(--font-semibold);
    text-decoration: none;
    transition: color var(--transition-base);
}

.auth-footer a:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

/* ========================================
   RESPONSIVE DESIGN
   ======================================== */

@media (max-width: 768px) {
    .auth-container {
        padding: var(--space-4) var(--space-3);
    }
    
    .auth-card {
        max-width: 100%;
    }
    
    .auth-header {
        padding: var(--space-6) var(--space-4) var(--space-4);
    }
    
    .auth-body {
        padding: var(--space-6) var(--space-4);
    }
    
    .progress-steps {
        padding: 0 var(--space-2);
    }
    
    .progress-step-circle {
        width: 32px;
        height: 32px;
        font-size: var(--text-xs);
    }
    
    .progress-step-label {
        font-size: 10px;
    }
    
    .form-actions {
        flex-direction: column;
        align-items: stretch;
    }
    
    .forgot-password-link {
        text-align: center;
    }
}

/* ========================================
   DARK MODE OVERRIDES
   ======================================== */

[data-theme="dark"] .auth-container {
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
}

[data-theme="dark"] .auth-container::before {
    background: radial-gradient(circle at 20% 50%, rgba(0, 217, 163, 0.1) 0%, transparent 50%),
                radial-gradient(circle at 80% 80%, rgba(102, 126, 234, 0.1) 0%, transparent 50%);
}

[data-theme="dark"] .auth-card {
    background: var(--bg-tertiary);
    border-color: var(--border-color);
}

[data-theme="dark"] .form-control {
    background-color: var(--bg-secondary);
}

[data-theme="dark"] .btn-social {
    background-color: var(--bg-secondary);
}

[data-theme="dark"] .auth-footer {
    background-color: var(--bg-secondary);
}

/* ========================================
   ACCESSIBILITY (WCAG 2.1 AA)
   ======================================== */

/* Focus visible for keyboard navigation */
.form-control:focus-visible,
.btn-social:focus-visible,
.btn-submit:focus-visible {
    outline: 3px solid var(--primary);
    outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    .form-control {
        border-width: 3px;
    }
    
    .btn-submit {
        border: 2px solid white;
    }
}

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

/* Screen reader only text */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}