:root {
  --color-gold-primary: #D4AF37;
  --color-gold-light: #F3E5AB;
  --color-gold-dark: #AA7A1E;
  --color-magenta: #E0076B;
  --color-magenta-hover: #B80456;
  --color-dark-bg: #0B0B0C;
  --color-dark-surface: #141416;
  --color-dark-card: #1C1C1F;
  --color-border: #2A2A2E;
  --color-border-active: #D4AF37;
  --color-text-light: #F5F5F7;
  --color-text-muted: #8E8E93;
  --font-serif: 'Cinzel', 'Playfair Display', Georgia, serif;
  --font-sans: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

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

body {
  background-color: var(--color-dark-bg);
  color: var(--color-text-light);
  font-family: var(--font-sans);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  overflow-x: hidden;
  position: relative;
  background-image: 
    radial-gradient(circle at 50% -20%, rgba(212, 175, 55, 0.15), transparent 60%),
    radial-gradient(circle at 100% 100%, rgba(224, 7, 107, 0.08), transparent 40%);
}

.brand-header {
  padding: 2.5rem 1rem 1.5rem;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.brand-logo {
  max-width: 220px;
  height: auto;
  filter: drop-shadow(0 4px 12px rgba(212, 175, 55, 0.25));
  margin-bottom: 0.75rem;
}

.collab-tag {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 2px;
  color: var(--color-gold-light);
  opacity: 0.9;
}

.main-container {
  width: 100%;
  max-width: 680px;
  padding: 0 1.25rem 3rem;
}

.form-wrapper {
  background: var(--color-dark-card);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  padding: 2.5rem;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.6);
  position: relative;
}

/* Stepper Progress Bar */
.stepper-header {
  display: flex;
  justify-content: space-between;
  margin-bottom: 2.5rem;
  position: relative;
}

.stepper-header::before {
  content: '';
  position: absolute;
  top: 18px;
  left: 10%;
  right: 10%;
  height: 2px;
  background: var(--color-border);
  z-index: 1;
}

.step-node {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
}

.step-bubble {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: var(--color-dark-surface);
  border: 2px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--color-text-muted);
  transition: var(--transition);
}

.step-node.active .step-bubble {
  border-color: var(--color-magenta);
  background: var(--color-magenta);
  color: #fff;
  box-shadow: 0 0 15px rgba(224, 7, 107, 0.4);
}

.step-node.completed .step-bubble {
  border-color: var(--color-gold-primary);
  background: var(--color-gold-primary);
  color: #000;
}

.step-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--color-text-muted);
}

.step-node.active .step-label {
  color: var(--color-text-light);
  font-weight: 600;
}

/* Form Steps */
.step-pane {
  display: none;
  animation: fadeIn 0.4s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.step-pane.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.section-title {
  font-family: var(--font-serif);
  font-size: 1.6rem;
  color: var(--color-gold-light);
  margin-bottom: 0.5rem;
  text-align: center;
}

.section-subtitle {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  text-align: center;
  margin-bottom: 2rem;
  line-height: 1.4;
}

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

.form-label {
  display: block;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 0.5rem;
  color: #CCC;
}

.form-input, .form-select, .form-textarea {
  width: 100%;
  padding: 0.9rem 1.1rem;
  background: var(--color-dark-surface);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  color: #FFF;
  font-family: var(--font-sans);
  font-size: 0.95rem;
  transition: var(--transition);
}

.form-input:focus, .form-select:focus, .form-textarea:focus {
  outline: none;
  border-color: var(--color-gold-primary);
  box-shadow: 0 0 10px rgba(212, 175, 55, 0.2);
}

/* Tier Selection Cards */
.tier-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.tier-card {
  border: 1px solid var(--color-border);
  border-radius: 10px;
  padding: 1.2rem;
  cursor: pointer;
  background: var(--color-dark-surface);
  transition: var(--transition);
  position: relative;
  text-align: left;
}

.tier-card:hover {
  border-color: rgba(212, 175, 55, 0.5);
  transform: translateY(-2px);
}

.tier-card.selected {
  border-color: var(--color-gold-primary);
  background: linear-gradient(135deg, rgba(212, 175, 55, 0.1), transparent);
}

.tier-title {
  font-family: var(--font-serif);
  font-size: 1.1rem;
  color: var(--color-gold-light);
  margin-bottom: 0.3rem;
}

.tier-price {
  font-size: 0.8rem;
  color: var(--color-magenta);
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.tier-desc {
  font-size: 0.78rem;
  color: var(--color-text-muted);
  line-height: 1.3;
}

/* Buttons */
.btn-group {
  display: flex;
  gap: 1rem;
  margin-top: 2rem;
}

.btn {
  flex: 1;
  padding: 1rem 1.5rem;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  border: none;
  transition: var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-magenta), #C2065B);
  color: #FFF;
  box-shadow: 0 4px 15px rgba(224, 7, 107, 0.35);
}

.btn-primary:hover {
  background: linear-gradient(135deg, var(--color-magenta-hover), #9C0347);
  box-shadow: 0 6px 20px rgba(224, 7, 107, 0.5);
}

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

.btn-secondary:hover {
  border-color: #666;
  color: #FFF;
}

/* OTP Boxes */
.otp-inputs-wrapper {
  display: flex;
  justify-content: center;
  gap: 0.75rem;
  margin: 2rem 0;
}

.otp-box {
  width: 50px;
  height: 56px;
  background: var(--color-dark-surface);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-gold-light);
  text-align: center;
  transition: var(--transition);
}

.otp-box:focus {
  border-color: var(--color-gold-primary);
  outline: none;
  box-shadow: 0 0 12px rgba(212, 175, 55, 0.3);
}

.alert-message {
  padding: 0.8rem;
  border-radius: 6px;
  font-size: 0.85rem;
  margin-top: 1rem;
  display: none;
  text-align: center;
}

.alert-error {
  background: rgba(255, 69, 58, 0.15);
  border: 1px solid rgba(255, 69, 58, 0.4);
  color: #FF453A;
}

.alert-success {
  background: rgba(48, 209, 88, 0.15);
  border: 1px solid rgba(48, 209, 88, 0.4);
  color: #30D158;
}

@media (max-width: 600px) {
  .form-wrapper { padding: 1.5rem; }
  .tier-grid { grid-template-columns: 1fr; }
  .otp-box { width: 42px; height: 50px; font-size: 1.25rem; }
}