.usbc-visual {
  min-width: 0;
  padding: clamp(18px, 4vw, 30px);
  background: var(--surface);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
}
.article-content .usbc-visual h2 { margin-top: 0; font-size: clamp(1.4rem, 3vw, 1.9rem); }
.article-content .usbc-visual > p { margin-top: 12px; }
.article-content .usbc-signal {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  list-style: none;
  gap: 16px;
  margin: 24px 0;
  padding: 0;
}
.article-content .usbc-signal li { position: relative; padding: 14px 12px; margin: 0; border-radius: var(--radius); background: var(--surface-muted); }
.usbc-signal li:not(:last-child)::after { content: "→"; position: absolute; right: -14px; top: 40%; color: var(--brand-accent); }
.usbc-signal span { display: block; color: var(--brand-accent); font-weight: 700; }
.usbc-signal strong { display: block; color: var(--text); }
.usbc-signal small { display: block; color: var(--muted); font-size: .85rem; line-height: 1.5; }
.usbc-form { margin-top: 24px; }
.usbc-form .button { background: var(--brand-accent); color: var(--brand-ink); border-color: transparent; }
.usbc-form .button:hover { background: var(--primary-hover); color: var(--brand-ink); }
.usbc-fields { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; margin-bottom: 20px; }
.usbc-fields label { display: grid; align-content: start; gap: 8px; color: var(--text); font-weight: 600; font-size: .95rem; }
.usbc-fields select { width: 100%; min-width: 0; min-height: 48px; padding: 10px 30px 10px 10px; color: var(--text); background: var(--bg); border: 1px solid var(--line-strong); border-radius: var(--radius); font: inherit; font-size: 1rem; }
.usbc-fields select:focus-visible, .usbc-form button:focus-visible { outline: 2px solid var(--brand-accent); outline-offset: 3px; }
.usbc-result { margin-top: 24px; padding-top: 24px; border-top: 1px solid var(--line-strong); }
.usbc-result h3 { color: var(--brand-accent); }
.article-content .usbc-result p { margin-top: 12px; }
.article-content .usbc-result ol { margin: 16px 0; padding-left: 24px; color: var(--muted); }
.article-content .usbc-result a { color: var(--primary-hover); text-decoration: underline; text-underline-offset: 3px; }
.usbc-method { padding-left: 16px; border-left: 3px solid var(--brand-accent); }
.usbc-visual [hidden] { display: none !important; }
@media (max-width: 680px) {
  .usbc-fields { grid-template-columns: minmax(0, 1fr); }
  .article-content .usbc-signal { grid-template-columns: minmax(0, 1fr); gap: 16px; }
  .article-content .usbc-signal li { padding: 12px 16px; }
  .usbc-signal li:not(:last-child)::after { content: "↓"; top: auto; right: 18px; bottom: -21px; }
  .usbc-form button { width: 100%; white-space: normal; }
}