/* ============================================
   COMPONENT LIBRARY - COURSERA PREMIUM
   Authentication & UI Components
   ============================================ */

/* ============================================
   AUTHENTICATION COMPONENTS
   ============================================ */

.auth-container {
  min-height: 100vh;
  background: var(--bg-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
  position: relative;
}

.auth-container::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(ellipse at center, rgba(0, 86, 210, 0.05) 0%, transparent 70%);
  animation: float 20s ease-in-out infinite;
}

@keyframes float {

  0%,
  100% {
    transform: translate(0, 0) rotate(0deg);
  }

  33% {
    transform: translate(30px, -30px) rotate(1deg);
  }

  66% {
    transform: translate(-20px, 20px) rotate(-1deg);
  }
}

.auth-card {
  background: white;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  width: 100%;
  max-width: 440px;
  position: relative;
  z-index: 10;
  border: 1px solid var(--border-light);
}

.auth-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--primary-500);
}

.auth-header {
  text-align: center;
  padding: var(--space-12) var(--space-8) var(--space-8);
  background: white;
}

.auth-logo {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  font-size: var(--text-2xl);
  font-weight: var(--font-bold);
  color: var(--primary-500);
  text-decoration: none;
  margin-bottom: var(--space-6);
  transition: var(--transition-fast);
}

.auth-logo:hover {
  color: var(--coursera-blue-dark);
  transform: translateY(-1px);
  text-decoration: none;
}

.auth-logo i {
  font-size: 1.4em;
  color: var(--primary-500);
}

.auth-title {
  font-size: var(--text-3xl);
  font-weight: var(--font-bold);
  color: var(--text-primary);
  margin: 0 0 var(--space-3);
  line-height: var(--leading-tight);
  letter-spacing: -0.025em;
}

.auth-subtitle {
  font-size: var(--text-lg);
  color: var(--text-secondary);
  margin: 0 0 var(--space-8);
  line-height: var(--leading-normal);
  font-weight: var(--font-normal);
}

.auth-body {
  padding: 0 var(--space-8) var(--space-8);
}

/* Enhanced Form Styles */
.auth-form {
  width: 100%;
}

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

.form-label {
  display: block;
  font-size: var(--text-sm);
  font-weight: var(--font-semibold);
  color: var(--text-primary);
  margin-bottom: var(--space-2);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.form-label i {
  color: var(--text-muted);
  font-size: 0.9em;
}

.form-control {
  width: 100%;
  padding: var(--space-4) var(--space-4);
  border: 2px solid var(--neutral-200);
  border-radius: var(--radius-lg);
  font-size: var(--text-base);
  font-weight: var(--font-normal);
  color: var(--text-primary);
  background: white;
  transition: all var(--transition-base);
  line-height: 1.5;
}

.form-control::placeholder {
  color: var(--text-light);
  font-weight: var(--font-normal);
}

.form-control:focus {
  outline: none;
  border-color: var(--primary-500);
  box-shadow: 0 0 0 3px rgba(0, 86, 210, 0.05);
  background: white;
}

.form-control:hover:not(:focus) {
  border-color: var(--neutral-300);
}

.focused .form-control {
  border-color: var(--coursera-blue);
  box-shadow: 0 0 0 3px rgba(0, 86, 210, 0.1);
}

/* Primary Auth Button */
.auth-btn {
  width: 100%;
  padding: var(--space-4) var(--space-6);
  font-size: var(--text-base);
  font-weight: var(--font-semibold);
  border-radius: var(--radius-lg);
  border: none;
  background: var(--primary-500);
  color: white;
  cursor: pointer;
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  margin: var(--space-6) 0;
  position: relative;
}

.auth-btn::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: left 0.5s;
}

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

.auth-btn:hover {
  background: var(--primary-600);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.auth-btn:active {
  transform: translateY(0);
  box-shadow:
    0 4px 6px -1px rgba(0, 86, 210, 0.3),
    0 2px 4px -1px rgba(0, 86, 210, 0.2);
}

.auth-btn i {
  font-size: 1.1em;
}

/* Loading State */
.loading-btn.loading {
  pointer-events: none;
  color: transparent;
}

.loading-btn.loading::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 20px;
  height: 20px;
  margin: -10px 0 0 -10px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-top-color: white;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

/* Social Login Buttons */
.social-login {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.social-btn {
  width: 100%;
  padding: var(--space-4) var(--space-6);
  border: 2px solid var(--neutral-200);
  border-radius: var(--radius-lg);
  background: white;
  color: var(--text-primary);
  font-weight: var(--font-semibold);
  font-size: var(--text-base);
  cursor: pointer;
  transition: all var(--transition-base);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-3);
  position: relative;
  overflow: hidden;
}

.social-btn:hover {
  border-color: var(--neutral-300);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.social-btn i {
  font-size: 1.2em;
}

.social-btn.google:hover {
  border-color: #db4437;
  color: #db4437;
}

.social-btn.github:hover {
  border-color: var(--neutral-800);
  color: var(--neutral-800);
}

.social-btn.facebook:hover {
  border-color: #1877f2;
  color: #1877f2;
}

/* Divider */
.auth-divider {
  position: relative;
  margin: var(--space-8) 0;
  text-align: center;
}

.auth-divider::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 0;
  right: 0;
  height: 1px;
  background: var(--neutral-200);
}

.auth-divider span {
  background: white;
  padding: 0 var(--space-4);
  color: var(--text-muted);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
}

/* Footer */
.auth-footer {
  text-align: center;
  padding: var(--space-6) var(--space-8) var(--space-8);
  background: var(--bg-gray-50);
  border-top: 1px solid var(--neutral-100);
}

.auth-footer p {
  color: var(--text-secondary);
  font-size: var(--text-sm);
  margin: 0 0 var(--space-4);
}

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

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

.auth-links {
  display: flex;
  justify-content: center;
  gap: var(--space-6);
  flex-wrap: wrap;
}

.auth-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  transition: var(--transition-base);
}

.auth-links a:hover {
  color: var(--coursera-blue);
}

/* Form Validation */
.field-validation-error {
  display: block;
  color: var(--coursera-red);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  margin-top: var(--space-2);
  animation: slideIn 0.2s ease-out;
}

.validation-summary-errors {
  background: #fef2f2;
  border: 1px solid #fecaca;
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  margin-bottom: var(--space-6);
  color: #dc2626;
  font-size: var(--text-sm);
  display: flex;
  align-items: flex-start;
  gap: var(--space-2);
}

.validation-summary-errors i {
  margin-top: 2px;
}

.validation-summary-errors ul {
  margin: 0;
  padding-left: var(--space-4);
}

.validation-summary-errors li {
  margin-bottom: var(--space-1);
}

/* Success Messages */
.success-message {
  background: #f0fdf4;
  border: 1px solid #bbf7d0;
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  margin-bottom: var(--space-6);
  color: #166534;
  font-size: var(--text-sm);
  display: flex;
  align-items: center;
  gap: var(--space-2);
  animation: slideIn 0.3s ease-out;
}

.success-message i {
  color: var(--coursera-green);
  font-size: 1.1em;
}

/* Form Enhancements */
.form-check {
  display: flex;
  align-items: flex-start;
  gap: var(--space-2);
}

.form-check-input {
  width: 18px;
  height: 18px;
  border: 2px solid var(--neutral-300);
  border-radius: var(--radius);
  cursor: pointer;
  transition: var(--transition-base);
  margin: 0;
  flex-shrink: 0;
  margin-top: 2px;
}

.form-check-input:checked {
  background-color: var(--coursera-blue);
  border-color: var(--coursera-blue);
  background-image: url("data:image/svg+xml,%3csvg viewBox='0 0 16 16' fill='white' xmlns='http://www.w3.org/2000/svg'%3e%3cpath d='m13.854 3.646-7.5 7.5a.5.5 0 0 1-.708 0l-3-3a.5.5 0 1 1 .708-.708L6 10.293l7.146-7.147a.5.5 0 0 1 .708.708z'/%3e%3c/svg%3e");
}

.form-check-input:focus {
  outline: none;
  box-shadow: 0 0 0 3px rgba(0, 86, 210, 0.1);
}

.form-check-label {
  color: var(--text-secondary);
  font-size: var(--text-sm);
  line-height: 1.5;
  cursor: pointer;
  margin: 0;
}

/* Password Strength Indicator */
.password-strength {
  margin-top: var(--space-2);
}

.password-strength small {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  font-size: var(--text-xs);
  font-weight: var(--font-medium);
  transition: var(--transition-base);
}

/* ============================================
   RESPONSIVE ADJUSTMENTS
   ============================================ */

@media (max-width: 640px) {
  .auth-container {
    padding: var(--space-3);
    align-items: flex-start;
    padding-top: var(--space-8);
  }

  .auth-card {
    max-width: 100%;
    border-radius: var(--radius-xl);
  }

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

  .auth-body {
    padding: 0 var(--space-6) var(--space-6);
  }

  .auth-footer {
    padding: var(--space-4) var(--space-6) var(--space-6);
  }

  .auth-title {
    font-size: var(--text-2xl);
  }

  .auth-subtitle {
    font-size: var(--text-base);
  }

  .auth-links {
    flex-direction: column;
    gap: var(--space-3);
  }
}

@media (max-width: 480px) {
  .auth-header {
    padding: var(--space-6) var(--space-4) var(--space-4);
  }

  .auth-body {
    padding: 0 var(--space-4) var(--space-4);
  }

  .auth-footer {
    padding: var(--space-4) var(--space-4) var(--space-4);
  }
}

/* ============================================
   ACCESSIBILITY IMPROVEMENTS
   ============================================ */

@media (prefers-reduced-motion: reduce) {
  .auth-container::before {
    animation: none;
  }

  .auth-btn::before {
    transition: none;
  }

  .field-validation-error,
  .success-message {
    animation: none;
  }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  .auth-card {
    border: 2px solid var(--neutral-800);
  }

  .form-control {
    border-width: 3px;
  }

  .auth-btn {
    border: 2px solid var(--coursera-blue-dark);
  }
}

/* Focus improvements for keyboard navigation */
.auth-btn:focus-visible,
.form-control:focus-visible,
.social-btn:focus-visible,
.form-check-input:focus-visible {
  outline: 2px solid var(--coursera-blue);
  outline-offset: 2px;
}

/* ============================================
   REGISTER PAGE SPECIFIC STYLES
   ============================================ */

.auth-card.register {
  max-width: 520px;
}

.register .auth-body {
  padding: 0 var(--space-8) var(--space-12);
}

.register .form-group {
  margin-bottom: var(--space-5);
}

.register .auth-btn {
  background: var(--coursera-green);
  margin: var(--space-8) 0 var(--space-6);
}

.register .auth-btn:hover {
  background: #00b366;
  box-shadow:
    0 10px 15px -3px rgba(0, 202, 114, 0.3),
    0 4px 6px -2px rgba(0, 202, 114, 0.2);
}

/* Enhanced animations */
.fade-in-up {
  animation: fadeInUp 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.slide-in {
  animation: slideIn 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}