* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: 'Poppins', sans-serif;
  min-height: 100vh;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  color: #333;
}

.container {
  width: 100%;
  max-width: 480px;
}

.card {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-radius: 20px;
  padding: 0;
  text-align: center;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1), 0 0 0 1px rgba(255, 255, 255, 0.1);
  animation: slideUp 0.8s ease;
  overflow: hidden;
}

.header {
  background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
  color: white;
  padding: 2rem 2rem 1.5rem;
  position: relative;
}

.header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grain" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="20" cy="20" r="1" fill="%23ffffff" opacity="0.1"/><circle cx="80" cy="40" r="0.8" fill="%23ffffff" opacity="0.1"/><circle cx="40" cy="80" r="1.2" fill="%23ffffff" opacity="0.1"/></pattern></defs><rect width="100" height="100" fill="url(%23grain)"/></svg>')
    repeat;
  opacity: 0.3;
}

.security-icon {
  font-size: 3rem;
  margin-bottom: 0.5rem;
  position: relative;
  z-index: 1;
}

h1 {
  font-size: 1.8rem;
  margin: 0 0 0.5rem;
  font-weight: 600;
  position: relative;
  z-index: 1;
}

.subtitle {
  font-size: 1.1rem;
  margin: 0;
  opacity: 0.9;
  position: relative;
  z-index: 1;
}

.content {
  padding: 2rem;
}

.description {
  font-size: 0.95rem;
  line-height: 1.6;
  color: #666;
  margin-bottom: 2rem;
}

.recaptcha-container {
  display: flex;
  justify-content: center;
  margin: 2rem 0;
}

.greeting {
  display: none;
  background: linear-gradient(135deg, #11998e, #38ef7d);
  color: white;
  padding: 2rem;
  border-radius: 15px;
  margin-top: 2rem;
  animation: successSlide 0.6s ease;
}

.success-icon {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.greeting h2 {
  font-size: 1.4rem;
  margin: 0 0 0.5rem;
  font-weight: 600;
}

.greeting p {
  margin: 0;
  opacity: 0.9;
  font-size: 0.95rem;
}

.footer {
  background: #f8f9fa;
  padding: 1rem 2rem;
  border-top: 1px solid #eee;
}

.footer small {
  color: #888;
  font-size: 0.8rem;
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(30px) scale(0.95);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@keyframes successSlide {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* レスポンシブデザイン */
@media (max-width: 480px) {
  .container {
    padding: 0.5rem;
  }

  .header {
    padding: 1.5rem 1.5rem 1rem;
  }

  .content {
    padding: 1.5rem;
  }

  h1 {
    font-size: 1.5rem;
  }

  .security-icon {
    font-size: 2.5rem;
  }
}