* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: #f6f7fb;
  color: #111;
}
code { font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace; }

.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255,255,255,.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid #e8e9f0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
}
.brand { font-weight: 700; }
.links { display: flex; align-items: center; gap: 10px; }
.links a { color: #222; text-decoration: none; padding: 6px 10px; border-radius: 10px; }
.links a.active { background: #111; color: #fff; }
.linkbtn {
  border: 0;
  background: transparent;
  cursor: pointer;
  padding: 6px 10px;
  border-radius: 10px;
}
.linkbtn:hover { background: #f0f1f7; }

.container { max-width: 980px; margin: 24px auto; padding: 0 16px; }
.card {
  background: #fff;
  border: 1px solid #e8e9f0;
  border-radius: 16px;
  padding: 16px;
  box-shadow: 0 8px 24px rgba(14,18,38,0.06);
}
h1 { font-size: 20px; margin: 0 0 12px 0; }
h2 { font-size: 16px; margin: 0 0 12px 0; }
.muted { color: #667; }
.small { font-size: 12px; }

.form { display: grid; gap: 12px; }
.grid2 { grid-template-columns: 1fr 1fr; }
.span2 { grid-column: 1 / span 2; }
label span { display: block; font-size: 12px; color: #556; margin-bottom: 6px; }
input, textarea {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid #d9dbea;
  border-radius: 12px;
  outline: none;
  background: #fff;
}
input:focus, textarea:focus { border-color: #7c5cff; box-shadow: 0 0 0 4px rgba(124,92,255,.12); }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 12px;
  border-radius: 12px;
  border: 1px solid #d9dbea;
  background: #fff;
  cursor: pointer;
  text-decoration: none;
  color: #111;
  font-weight: 600;
}
.btn.primary { background: #111; color: #fff; border-color: #111; }
.btn.danger { background: #fff0f2; border-color: #ffccd3; color: #a11; }

.alert {
  background: #fff0f2;
  border: 1px solid #ffccd3;
  color: #a11;
  padding: 10px 12px;
  border-radius: 12px;
  margin-bottom: 10px;
}
.toast {
  background: #eefdf5;
  border: 1px solid #bff0d2;
  color: #095;
  padding: 10px 12px;
  border-radius: 12px;
  margin-bottom: 10px;
}

.inv { border-top: 1px dashed #e8e9f0; padding: 12px 0; }
.inv:first-of-type { border-top: 0; padding-top: 0; }
.inv-head { display: flex; justify-content: space-between; align-items: center; gap: 10px; }
.inv-title { font-weight: 800; }
.copyrow { display: flex; gap: 8px; margin-top: 10px; }
.copyrow input { flex: 1; }
.mono { font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace; }
details { margin-top: 10px; }
summary { cursor: pointer; color: #333; }

@media (max-width: 720px) {
  .grid2 { grid-template-columns: 1fr; }
  .span2 { grid-column: auto; }
  .inv-head { flex-direction: column; align-items: flex-start; }
  .copyrow { flex-direction: column; }
}