body {
  margin:0;
  font-family:sans-serif;
  color:#333;
}
.container {
  max-width:800px;
  margin:0 auto;
  padding:16px;
  display:flex;
  justify-content:space-between;
  align-items:center;
}
.logo {
  height:40px;
}
.upload-btn {
  padding:8px 16px;
  background:#0070f3;
  color:#fff;
  border:none;
  border-radius:4px;
  cursor:pointer;
}
.hero {
  text-align:center;
  padding:80px 16px;
}
.hero h1 {
  font-size:1.8rem;
  margin:0;
}
.preview {
  max-width:800px;
  margin:40px auto;
  padding:16px;
}
.certificate-placeholder {
  border:2px dashed #0070f3;
  padding:80px;
  text-align:center;
  color:#777;
}
footer {
  text-align:center;
  padding:16px;
  font-size:0.8rem;
  color:#999;
}
@media(min-width:600px) {
  .hero h1 {
    font-size:2.4rem;
  }
}