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

:root {
  --obsidian: #0A0A0B;
  --smoke: #1A1A1C;
  --graphite: #2D2D30;
  --sterling: #8A8A8E;
  --ivory: #F5F5F3;
  --pearl: #FAFAF8;
  --champagne: #C9A962;
  --champagne-light: #E8D5A3;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--obsidian);
  color: var(--ivory);
  line-height: 1.5;
  min-height: 100vh;
}

.container {
  max-width: 520px;
  margin: 0 auto;
  padding: 0 24px;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 24px 0;
  margin-bottom: 48px;
  border-bottom: 1px solid var(--graphite);
}

.logo {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 2px;
}

.logo img {
  height: 32px;
  width: auto;
}

.header-link {
  font-size: 14px;
  color: var(--sterling);
  text-decoration: none;
}

.header-link:hover {
  color: var(--ivory);
}

h1 {
  font-size: 32px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--pearl);
}

h2 {
  font-size: 24px;
  font-weight: 600;
  margin-bottom: 24px;
  color: var(--pearl);
}

h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--ivory);
}

p {
  color: var(--sterling);
  margin-bottom: 32px;
}

label {
  display: block;
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 6px;
  color: var(--ivory);
}

input, select, textarea {
  width: 100%;
  padding: 14px 16px;
  font-size: 15px;
  border: 1px solid var(--graphite);
  border-radius: 6px;
  margin-bottom: 16px;
  font-family: inherit;
  background: var(--smoke);
  color: var(--ivory);
}

input::placeholder {
  color: var(--sterling);
}

input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--champagne);
}

select {
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%238A8A8E' stroke-width='2'%3E%3Cpolyline points='6 9 12 15 18 9'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 16px center;
}

.checkbox-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin-bottom: 16px;
}

.checkbox-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px;
  background: var(--smoke);
  border: 1px solid var(--graphite);
  border-radius: 6px;
  cursor: pointer;
  transition: border-color 0.15s;
}

.checkbox-item:hover {
  border-color: var(--sterling);
}

.checkbox-item input {
  width: 18px;
  height: 18px;
  margin: 0;
  accent-color: var(--champagne);
}

.checkbox-item span {
  font-size: 14px;
}

.url-input-group {
  display: none;
  margin-bottom: 16px;
}

.url-input-group.visible {
  display: block;
}

.url-input-group label {
  font-size: 13px;
  margin-bottom: 4px;
}

.url-input-group input {
  margin-bottom: 8px;
  padding: 12px 14px;
  font-size: 14px;
}

.btn {
  display: inline-block;
  padding: 16px 28px;
  font-size: 15px;
  font-weight: 600;
  background: var(--champagne);
  color: var(--obsidian);
  border: none;
  border-radius: 6px;
  cursor: pointer;
  width: 100%;
  transition: background 0.15s;
}

.btn:hover {
  background: var(--champagne-light);
}

.btn:disabled {
  background: var(--sterling);
  cursor: not-allowed;
}

.form-section {
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--graphite);
}

.form-section:last-of-type {
  border-bottom: none;
}

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.form-group.full-width {
  grid-column: 1 / -1;
}

.referral-status {
  font-size: 13px;
  margin-top: -8px;
  margin-bottom: 16px;
}

.referral-status.valid {
  color: #2E7D5F;
}

.referral-status.invalid {
  color: #C43C3C;
}

.error-message {
  color: #C43C3C;
  font-size: 13px;
  margin-top: -8px;
  margin-bottom: 16px;
}

.alert {
  padding: 16px;
  border-radius: 6px;
  margin-bottom: 24px;
}

.alert-error {
  background: rgba(196, 60, 60, 0.1);
  border: 1px solid #C43C3C;
  color: #C43C3C;
}

.success-page {
  text-align: center;
  padding: 60px 0;
}

.success-page h1 {
  margin-bottom: 16px;
}

.success-details {
  text-align: left;
  background: var(--smoke);
  padding: 20px;
  border-radius: 8px;
  margin: 24px 0;
}

.success-details h3 {
  margin-bottom: 12px;
}

.success-details p {
  margin-bottom: 8px;
  font-size: 14px;
}

.user-type-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin-top: 24px;
}

.user-type-card {
  padding: 20px;
  background: var(--smoke);
  border: 1px solid var(--graphite);
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.15s;
}

.user-type-card:hover {
  border-color: var(--champagne);
}

.user-type-card h3 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 4px;
  color: var(--ivory);
}

.user-type-card p {
  font-size: 13px;
  margin: 0;
  color: var(--sterling);
}

.loading-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(10, 10, 11, 0.9);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
}

.loading-overlay.hidden {
  display: none;
}

.hidden {
  display: none !important;
}

.spinner {
  width: 32px;
  height: 32px;
  border: 3px solid var(--graphite);
  border-top-color: var(--champagne);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

.required {
  color: #C43C3C;
}

.tagline {
  font-size: 15px;
  color: var(--sterling);
  margin-bottom: 40px;
}

.footer {
  text-align: center;
  margin-top: 60px;
  padding-top: 24px;
  border-top: 1px solid var(--graphite);
  font-size: 13px;
  color: var(--sterling);
}

.footer a {
  color: var(--sterling);
  text-decoration: none;
}

.footer a:hover {
  color: var(--champagne);
}

.form-actions {
  display: flex;
  gap: 12px;
  margin-top: 24px;
}

.form-actions .btn {
  flex: 1;
}

.back-btn {
  background: var(--graphite);
  color: var(--ivory);
}

.back-btn:hover {
  background: var(--sterling);
}

main {
  padding-bottom: 40px;
}

@media (max-width: 500px) {
  .form-grid {
    grid-template-columns: 1fr;
  }
  
  .user-type-grid {
    grid-template-columns: 1fr;
  }
  
  .checkbox-grid {
    grid-template-columns: 1fr;
  }
  
  h1 {
    font-size: 26px;
  }
}