body {
  font-family: 'Segoe UI', Arial, sans-serif;
  background: #f8fafc;
  color: #222;
  margin: 0;
  padding: 0;
}
main {
  max-width: 600px;
  margin: 2rem auto;
  padding: 1rem;
  background: #fff;
  border-radius: 10px;
  box-shadow: 0 2px 12px rgba(0,0,0,0.07);
}
h1 {
  font-size: 2rem;
  margin-bottom: 1rem;
}
ul {
  list-style: disc inside;
  padding-left: 1.5rem;
}
.preview-link {
  color: #2563eb;
  text-decoration: underline;
  cursor: pointer;
  position: relative;
  outline: none;
  transition: color 0.2s;
}
.preview-link:focus, .preview-link:hover {
  color: #1d4ed8;
}
#link-preview {
  position: fixed;
  z-index: 1000;
  min-width: 220px;
  max-width: 320px;
  background: #fff;
  border: 1.5px solid #2563eb;
  border-radius: 8px;
  box-shadow: 0 4px 24px rgba(37,99,235,0.13);
  padding: 1rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.18s cubic-bezier(.4,2,.6,1);
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  font-size: 1rem;
}
#link-preview.visible {
  opacity: 1;
  pointer-events: auto;
}
#link-preview img {
  max-width: 100%;
  max-height: 90px;
  border-radius: 5px;
  object-fit: contain;
  background: #f1f5f9;
}
#link-preview .preview-title {
  font-weight: 600;
  color: #2563eb;
  font-size: 1.1rem;
}
#link-preview .preview-desc {
  color: #444;
  font-size: 0.98rem;
}
.visually-hidden {
  position: absolute !important;
  height: 1px; width: 1px;
  overflow: hidden;
  clip: rect(1px, 1px, 1px, 1px);
  white-space: nowrap;
}
@media (max-width: 700px) {
  main { max-width: 98vw; }
  #link-preview { max-width: 90vw; }
}