/* Reset and base styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --color-bg: #FAFAFA;
  --color-surface: #FFFFFF;
  --color-text-primary: #0A0A0B;
  --color-text-secondary: #6B7280;
  --color-text-muted: #9CA3AF;
  --color-accent: #D4AF37;
  --color-accent-hover: #C29D2F;
  --color-border: #E5E5E5;
  --color-success: #10B981;
  --color-error: #EF4444;
  --font-stack: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
  --max-width: 720px;
}

body {
  font-family: var(--font-stack);
  background-color: var(--color-bg);
  color: var(--color-text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Container */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 40px 24px;
}

/* Header */
.header {
  text-align: center;
  margin-bottom: 60px;
}

.logo {
  font-size: 48px;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--color-text-primary);
  margin-bottom: 16px;
}

.divider {
  width: 120px;
  height: 3px;
  background-color: var(--color-accent);
  margin: 0 auto 20px;
}

.tagline {
  font-size: 18px;
  color: var(--color-text-secondary);
  font-weight: 400;
}

/* Main content */
.main {
  background-color: var(--color-surface);
  border-radius: 16px;
  padding: 48px 40px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
}

/* Intro section */
.intro {
  text-align: center;
  margin-bottom: 48px;
}

.intro h2 {
  font-size: 32px;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--color-text-primary);
}

.description {
  font-size: 18px;
  line-height: 1.7;
  color: var(--color-text-secondary);
  max-width: 560px;
  margin: 0 auto;
}

/* Features section */
.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 32px;
  margin-bottom: 56px;
  padding-bottom: 48px;
  border-bottom: 1px solid var(--color-border);
}

.feature {
  text-align: center;
}

.feature-icon {
  font-size: 40px;
  display: block;
  margin-bottom: 12px;
}

.feature h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--color-text-primary);
}

.feature p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* Signup section */
.signup {
  text-align: center;
  margin-bottom: 48px;
}

.signup h2 {
  font-size: 28px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--color-text-primary);
}

.signup-description {
  font-size: 16px;
  color: var(--color-text-secondary);
  margin-bottom: 32px;
}

/* Form */
.signup-form {
  max-width: 480px;
  margin: 0 auto;
}

.form-group {
  display: flex;
  gap: 12px;
  margin-bottom: 16px;
}

.email-input {
  flex: 1;
  padding: 14px 18px;
  font-size: 16px;
  font-family: var(--font-stack);
  border: 2px solid var(--color-border);
  border-radius: 8px;
  background-color: var(--color-surface);
  color: var(--color-text-primary);
  transition: border-color 0.2s;
}

.email-input:focus {
  outline: none;
  border-color: var(--color-accent);
}

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

.submit-button {
  padding: 14px 32px;
  font-size: 16px;
  font-weight: 600;
  font-family: var(--font-stack);
  background-color: var(--color-accent);
  color: var(--color-text-primary);
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: background-color 0.2s, transform 0.1s;
  white-space: nowrap;
}

.submit-button:hover {
  background-color: var(--color-accent-hover);
}

.submit-button:active {
  transform: scale(0.98);
}

.submit-button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.form-note {
  font-size: 13px;
  color: var(--color-text-muted);
  margin-top: 12px;
}

/* Messages */
.message {
  max-width: 480px;
  margin: 24px auto 0;
  padding: 16px 20px;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 12px;
}

.message-icon {
  font-size: 20px;
  font-weight: 700;
}

.success-message {
  background-color: #D1FAE5;
  color: #065F46;
  border: 1px solid #10B981;
}

.error-message {
  background-color: #FEE2E2;
  color: #991B1B;
  border: 1px solid #EF4444;
}

/* Sample section */
.sample {
  padding-top: 48px;
  border-top: 1px solid var(--color-border);
}

.sample h3 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 20px;
  text-align: center;
  color: var(--color-text-primary);
}

.sample-list {
  list-style: none;
  max-width: 400px;
  margin: 0 auto;
}

.sample-list li {
  padding: 12px 0;
  font-size: 16px;
  color: var(--color-text-secondary);
  border-bottom: 1px dashed var(--color-border);
  position: relative;
  padding-left: 28px;
}

.sample-list li:last-child {
  border-bottom: none;
}

.sample-list li::before {
  content: '→';
  position: absolute;
  left: 0;
  color: var(--color-accent);
  font-weight: 600;
}

/* Footer */
.footer {
  text-align: center;
  margin-top: 60px;
  padding-top: 32px;
  border-top: 1px solid var(--color-border);
}

.footer-logo {
  font-size: 20px;
  font-weight: 600;
  letter-spacing: 0.1em;
  margin-bottom: 8px;
  color: var(--color-text-primary);
}

.footer-text {
  font-size: 13px;
  color: var(--color-text-muted);
  margin-bottom: 4px;
}

.footer-copyright {
  font-size: 12px;
  color: var(--color-text-muted);
}

/* Responsive */
@media (max-width: 640px) {
  .container {
    padding: 24px 16px;
  }

  .main {
    padding: 32px 24px;
  }

  .logo {
    font-size: 36px;
  }

  .intro h2 {
    font-size: 26px;
  }

  .description {
    font-size: 16px;
  }

  .features {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .form-group {
    flex-direction: column;
  }

  .submit-button {
    width: 100%;
  }
}