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

:root {
  /* Dark Theme - SaaS Modern */
  --background: #0F1419;
  --surface: #1A1F26;
  --surface-elevated: #222831;
  --surface-hover: #2A3038;

  /* Text Colors */
  --text-primary: #E8EAED;
  --text-secondary: #9CA3AF;
  --text-muted: #6B7280;

  /* Brand Colors */
  --primary-color: #3B82F6;
  --primary-hover: #2563EB;
  --primary-light: rgba(59, 130, 246, 0.15);
  --accent-color: #F59E0B;

  /* Status Colors */
  --success-color: #10B981;
  --success-light: rgba(16, 185, 129, 0.15);
  --warning-color: #F59E0B;
  --warning-light: rgba(245, 158, 11, 0.15);
  --danger-color: #EF4444;
  --danger-light: rgba(239, 68, 68, 0.15);
  --info-color: #06B6D4;
  --info-light: rgba(6, 182, 212, 0.15);

  /* Borders & Dividers */
  --border: #2A3038;
  --border-light: #374151;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: var(--background);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.btn-primary {
  background: var(--primary-color);
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
  width: 100%;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover:not(:disabled) {
  background: var(--primary-hover);
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}

.btn-primary:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

.btn-secondary {
  background: var(--surface-elevated);
  color: var(--text-primary);
  border: 1px solid var(--border);
  padding: 0.5rem 1rem;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.875rem;
  font-weight: 500;
  transition: all 0.2s ease;
}

.btn-secondary:hover {
  background: var(--surface-hover);
  border-color: var(--border-light);
}

.error-message {
  color: var(--danger-color);
  padding: 0.875rem 1rem;
  margin-top: 1rem;
  border-radius: 8px;
  background: var(--danger-light);
  border: 1px solid rgba(239, 68, 68, 0.3);
  font-size: 0.875rem;
}

/* Login Page */
.login-container {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: 1rem;
}

.login-card {
  background: var(--surface);
  padding: 3rem;
  border-radius: 12px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-lg);
  width: 100%;
  max-width: 440px;
}

.login-logo {
  display: block;
  width: 80px;
  height: auto;
  margin: 0 auto 1rem;
}

.login-card h1 {
  margin-bottom: 0.5rem;
  text-align: center;
  color: var(--text-primary);
  font-size: 1.875rem;
  font-weight: 600;
  letter-spacing: -0.025em;
}

.subtitle {
  color: var(--text-secondary);
  margin-bottom: 2.5rem;
  font-size: 0.925rem;
  line-height: 1.5;
  text-align: center;
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.625rem;
  font-weight: 500;
  font-size: 0.875rem;
  color: var(--text-primary);
}

.form-group input {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 0.95rem;
  background: var(--surface-elevated);
  color: var(--text-primary);
  transition: all 0.2s ease;
}

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

.form-group input::placeholder {
  color: var(--text-muted);
}

.form-group small {
  display: block;
  margin-top: 0.5rem;
  color: var(--text-secondary);
  font-size: 0.8125rem;
  line-height: 1.4;
}

@media (max-width: 480px) {
  .login-card {
    padding: 2rem 1.5rem;
  }
}