.app-header{border-bottom:1px solid var(--line);background:color-mix(in srgb, var(--paper) 97%, transparent);z-index:20;grid-template-columns:minmax(210px,1fr) auto minmax(280px,560px) minmax(110px,1fr);align-items:center;gap:24px;min-height:72px;padding:12px 24px;display:grid;position:relative}.app-header .brand{color:inherit;text-decoration:none}.mode-switch{border:1px solid var(--line);background:var(--surface-muted);border-radius:7px;gap:3px;padding:3px;display:inline-flex}.mode-button{height:32px;color:var(--muted);background:0 0;border:0;border-radius:5px;justify-content:center;align-items:center;padding:0 12px;font-size:13px;font-weight:650;text-decoration:none;display:inline-flex}.mode-button.active{color:var(--ink);background:var(--surface);box-shadow:0 1px 3px #17232c1a}.mode-button:disabled{cursor:not-allowed;opacity:.55}.header-mode-switch{flex-wrap:wrap;justify-self:start;max-width:100%}.header-actions{grid-column:-2;justify-self:end;align-items:center;gap:14px;display:flex}.header-about-link{color:var(--muted);font-size:13px;font-weight:650;text-decoration:none}.header-about-link:hover,.header-about-link:focus-visible{color:var(--teal)}@media (max-width:900px){.app-header{grid-template-columns:minmax(0,1fr) auto auto}.header-mode-switch{grid-area:1/2}.header-actions{grid-area:1/3}}@media (max-width:560px){.app-header{grid-template-columns:minmax(0,1fr) auto;gap:10px;padding:10px 12px 12px}.header-mode-switch{grid-area:2/1/auto/-1}.header-actions{grid-area:1/2;gap:8px}.mode-button{padding:0 9px}.header-about-link{font-size:12px}}