html:has(.tool-page) { overscroll-behavior: none; }
.tool-page { display: flex; flex-direction: column; height: 100dvh; overflow: hidden; overscroll-behavior: none; }
.tool-page .site-header { flex: none; position: relative; padding: 0.6rem var(--gutter); }
.tool-main { flex: 1; min-height: 0; display: flex; flex-direction: column; }

.tool-intro { flex: none; display: flex; align-items: center; gap: 0.75rem; padding: 0.5rem var(--gutter); border-bottom: 1px solid var(--line); background: var(--surface); }
.tool-breadcrumbs { display: flex; align-items: center; gap: 0.5rem; margin: 0; font-size: 0.85rem; }
.tool-breadcrumbs a { padding: 0.15rem 0.55rem; border-radius: 999px; background: var(--surface-raised); color: var(--muted); text-decoration: none; }
.tool-breadcrumbs a:hover { color: var(--text); }
.tool-breadcrumb-separator { color: var(--muted); }
.tool-title { display: flex; align-items: center; gap: 0.5rem; margin: 0; font-size: 1.05rem; letter-spacing: -0.01em; white-space: nowrap; }
.tool-icon { display: inline-grid; place-items: center; width: 1.7rem; height: 1.7rem; border-radius: 6px; background: var(--accent); color: var(--accent-ink); font: 700 0.75rem var(--mono); }
.tool-tagline { flex: 1; min-width: 0; margin: 0; padding-left: 0.75rem; border-left: 1px solid var(--line); color: var(--muted); font-size: 0.85rem; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.tool-about-button { flex: none; padding: 0.25rem 0.7rem; border: 1px solid var(--line); border-radius: 999px; background: transparent; color: var(--muted); font: inherit; font-size: 0.8rem; cursor: pointer; }
.tool-about-button:hover { color: var(--text); border-color: var(--accent); }

.tool-app { flex: 1; min-height: 0; }
.tool-noscript { margin: 2rem var(--gutter); }

.tool-about { width: min(46rem, calc(100vw - 2rem)); max-height: min(85dvh, 60rem); margin: auto; padding: 1.5rem 1.75rem; overflow: auto; overscroll-behavior: contain; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); color: var(--text); font-size: 0.95rem; }
.tool-about::backdrop { background: rgb(0 0 0 / 0.55); }
.tool-about h2 { margin: 0 2rem 0.75rem 0; font-size: 1.4rem; }
.tool-about h3 { margin: 1.5rem 0 0.4rem; font-size: 1.05rem; }
.tool-about li { margin-bottom: 0.35rem; }
.tool-about-close { position: sticky; top: 0; float: right; width: 2rem; height: 2rem; margin: -0.5rem -0.75rem 0 0; border: 1px solid var(--line); border-radius: 50%; background: var(--surface-raised); color: var(--text); font-size: 1.2rem; line-height: 1; cursor: pointer; }
.tool-faq dt { margin-top: 0.9rem; font-weight: 600; }
.tool-faq dd { margin: 0.2rem 0 0; color: var(--muted); }

@media (max-width: 800px) {
  .tool-tagline, .tool-breadcrumbs { display: none; }
  .tool-title { min-width: 0; font-size: 0.95rem; white-space: normal; line-height: 1.25; }
  .tool-intro { justify-content: space-between; }
}