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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: linear-gradient(135deg, #0f0f1a 0%, #1a1a2e 50%, #16213e 100%);
  min-height: 100vh;
  color: #fff;
  display: flex;
  flex-direction: column;
}

.container {
  max-width: 500px;
  margin: 0 auto;
  padding: 0 20px;
}

.optin-container {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 0;
}

.optin-card {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 20px;
  padding: 50px 40px;
  text-align: center;
  backdrop-filter: blur(10px);
}

.badge {
  display: inline-block;
  background: linear-gradient(135deg, #22c55e, #16a34a);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 2px;
  padding: 8px 20px;
  border-radius: 20px;
  margin-bottom: 25px;
}

h1 {
  font-size: 2.2rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 12px;
}

.highlight {
  background: linear-gradient(135deg, #60a5fa, #a78bfa);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.subtitle {
  font-size: 1.1rem;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 30px;
}

.preview-box {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 12px;
  padding: 20px;
  margin-bottom: 30px;
  text-align: left;
}

.preview-header {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  margin-bottom: 15px;
  padding-bottom: 12px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.file-icon {
  font-size: 1.3rem;
}

.preview-list {
  list-style: none;
}

.preview-list li {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 0;
  font-size: 0.95rem;
  color: rgba(255, 255, 255, 0.85);
}

.check {
  color: #22c55e;
  font-weight: 700;
}

.form-group {
  margin-bottom: 15px;
}

.form-group input {
  width: 100%;
  padding: 16px 20px;
  font-size: 1rem;
  border: 2px solid rgba(255, 255, 255, 0.15);
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.05);
  color: #fff;
  transition: border-color 0.3s ease;
}

.form-group input:focus {
  outline: none;
  border-color: #60a5fa;
}

.form-group input::placeholder {
  color: rgba(255, 255, 255, 0.5);
}

.submit-btn {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  background: linear-gradient(135deg, #3b82f6, #8b5cf6);
  color: #fff;
  font-size: 1.1rem;
  font-weight: 700;
  padding: 18px 30px;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 8px 25px rgba(59, 130, 246, 0.3);
}

.submit-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 35px rgba(59, 130, 246, 0.4);
}

.submit-btn:disabled {
  opacity: 0.7;
  cursor: not-allowed;
  transform: none;
}

.btn-arrow {
  font-size: 1.2rem;
  transition: transform 0.3s ease;
}

.submit-btn:hover .btn-arrow {
  transform: translateX(5px);
}

.privacy-text {
  margin-top: 15px;
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.5);
}

.success-message {
  background: rgba(34, 197, 94, 0.15);
  border: 1px solid rgba(34, 197, 94, 0.3);
  border-radius: 12px;
  padding: 30px;
}

.success-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 60px;
  height: 60px;
  background: linear-gradient(135deg, #22c55e, #16a34a);
  border-radius: 50%;
  font-size: 1.8rem;
  margin-bottom: 15px;
}

.success-message h3 {
  font-size: 1.4rem;
  margin-bottom: 8px;
}

.success-message p {
  color: rgba(255, 255, 255, 0.8);
}

.error-message {
  background: rgba(220, 38, 38, 0.15);
  border: 1px solid rgba(220, 38, 38, 0.3);
  border-radius: 8px;
  padding: 12px 15px;
  margin-top: 15px;
  color: #fca5a5;
  font-size: 0.9rem;
}

.footer {
  background: rgba(0, 0, 0, 0.3);
  padding: 20px 0;
  text-align: center;
}

.footer p {
  color: rgba(255, 255, 255, 0.4);
  font-size: 0.85rem;
}

@media (max-width: 600px) {
  .optin-card {
    padding: 35px 25px;
  }
  
  h1 {
    font-size: 1.7rem;
  }
  
  .subtitle {
    font-size: 1rem;
  }
}