body { font-family: Arial, sans-serif; background: #f7f7f9; margin: 0; padding: 24px; }
.container { max-width: 1000px; margin: 0 auto; }
h1 { margin-top: 0; }

.grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

@media (min-width: 900px) {
  .grid { grid-template-columns: 1fr 1fr 1fr; }
}

.card {
  background: #fff;
  border: 1px solid #e8e8ef;
  border-radius: 12px;
  padding: 16px;
}

label { display: block; margin: 10px 0; }
input, textarea {
  width: 100%;
  box-sizing: border-box;
  padding: 10px;
  border-radius: 10px;
  border: 1px solid #dcdce6;
  outline: none;
}
textarea { resize: vertical; }

button {
  margin-top: 10px;
  width: 100%;
  padding: 10px 12px;
  border: 0;
  border-radius: 10px;
  background: #0b66c3;
  color: #fff;
  cursor: pointer;
}

.result { margin-top: 10px; font-size: 14px; }
.sharebox {
  border: 1px dashed #cfd4e6;
  border-radius: 12px;
  padding: 12px;
  background: #fafbff;
  word-break: break-word;
}
.help { color: #666; font-size: 14px; }
.muted { color: #999; }