:root {
  --primary-color: #2563EB;
  --primary-hover: #1D4ED8;
  --accent-color: #FBBF24;
  --accent-hover: #F59E0B;
  --bg-color: #F8FAFC;
  --card-bg: #FFFFFF;
  --text-main: #1E293B;
  --text-muted: #64748B;
  --border-color: #E2E8F0;
  --error-color: #EF4444;
  --success-color: #10B981;
  
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --radius-md: 0.5rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  
  --transition: all 0.3s ease;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: 'Inter', 'Roboto', sans-serif;
}

body {
  background-color: var(--bg-color);
  color: var(--text-main);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 1rem;
}

.auth-container {
  width: 100%;
  max-width: 400px;
  background-color: var(--card-bg);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  padding: 2rem;
  animation: slideUp 0.5s ease;
  position: relative;
  overflow: hidden;
}

.auth-container.register {
  max-width: 500px;
}

.auth-header {
  text-align: center;
  margin-bottom: 2rem;
}

.auth-logo {
  font-size: 2rem;
  font-weight: 800;
  color: var(--primary-color);
  margin-bottom: 0.5rem;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.auth-logo span {
  color: var(--accent-color);
}

.auth-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.auth-subtitle {
  color: var(--text-muted);
  font-size: 0.875rem;
}

.form-group {
  margin-bottom: 1.25rem;
  position: relative;
}

.form-label {
  display: block;
  font-size: 0.875rem;
  font-weight: 500;
  margin-bottom: 0.5rem;
  color: var(--text-main);
}

.form-input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.form-input-wrapper .material-icons {
  position: absolute;
  left: 1rem;
  color: var(--text-muted);
  font-size: 1.25rem;
}

.form-input {
  width: 100%;
  padding: 0.75rem 1rem 0.75rem 2.75rem;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  font-size: 1rem;
  outline: none;
  transition: var(--transition);
  background: var(--bg-color);
}

.form-input:focus {
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
  background: var(--card-bg);
}

.form-input-wrapper .toggle-password {
  position: absolute;
  right: 1rem;
  left: auto;
  cursor: pointer;
  transition: var(--transition);
}
.form-input-wrapper .toggle-password:hover {
  color: var(--primary-color);
}

.btn {
  width: 100%;
  padding: 0.875rem;
  border: none;
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
}

.btn-primary {
  background-color: var(--primary-color);
  color: white;
  box-shadow: 0 4px 14px 0 rgba(37, 99, 235, 0.39);
}

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

.btn-outline {
  background-color: transparent;
  border: 1px solid var(--border-color);
  color: var(--text-main);
}

.btn-outline:hover {
  background-color: var(--bg-color);
  border-color: var(--primary-color);
}

.auth-links {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 1.5rem;
  font-size: 0.875rem;
}

.auth-link {
  color: var(--primary-color);
  text-decoration: none;
  font-weight: 500;
  transition: var(--transition);
}

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

.divider {
  display: flex;
  align-items: center;
  text-align: center;
  margin: 1.5rem 0;
  color: var(--text-muted);
  font-size: 0.875rem;
}
.divider::before,
.divider::after {
  content: '';
  flex: 1;
  border-bottom: 1px solid var(--border-color);
}
.divider:not(:empty)::before {
  margin-right: .25em;
}
.divider:not(:empty)::after {
  margin-left: .25em;
}

.checkbox-group {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  color: var(--text-muted);
  cursor: pointer;
}

.checkbox-group input[type="checkbox"] {
  width: 1rem;
  height: 1rem;
  accent-color: var(--primary-color);
  cursor: pointer;
}

.error-message {
  color: var(--error-color);
  font-size: 0.75rem;
  margin-top: 0.25rem;
  display: none;
}
.form-group.error .error-message {
  display: block;
}
.form-group.error .form-input {
  border-color: var(--error-color);
}

.otp-container {
  display: flex;
  gap: 0.5rem;
  justify-content: center;
  margin-bottom: 1.5rem;
}

.otp-input {
  width: 3rem;
  height: 3rem;
  text-align: center;
  font-size: 1.5rem;
  font-weight: 700;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background: var(--bg-color);
  transition: var(--transition);
}
.otp-input:focus {
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
  background: var(--card-bg);
  outline: none;
}

.password-strength {
  height: 4px;
  background-color: var(--border-color);
  border-radius: 2px;
  margin-top: 0.5rem;
  overflow: hidden;
}
.strength-bar {
  height: 100%;
  width: 0;
  transition: var(--transition);
}
.strength-text {
  font-size: 0.75rem;
  margin-top: 0.25rem;
  text-align: right;
  color: var(--text-muted);
}

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

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

.spinner {
  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;
}
.btn.loading .spinner {
  display: block;
}
.btn.loading .btn-text {
  display: none;
}

.row {
  display: flex;
  gap: 1rem;
}
.col {
  flex: 1;
}

@media (max-width: 480px) {
  .auth-container {
    padding: 1.5rem;
    box-shadow: none;
    border-radius: 0;
    background: transparent;
  }
  body {
    background-color: var(--card-bg);
    align-items: flex-start;
  }
  .row {
    flex-direction: column;
    gap: 0;
  }
}

.skeleton {
  background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
  background-size: 200% 100%;
  animation: skeletonLoading 1.5s infinite;
  border-radius: var(--radius-md);
}

@keyframes skeletonLoading {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}