/* Design Theory — the shared site header, standalone, for pages that keep their own stylesheet
   (Apps & Extensions, AI Chat Agent, Website Packages). Same look as the header in dt.css.
   Everything is scoped to the header, its phone menu and the skip link, so the page's own styles are untouched. */
header.nav, nav.menu-sheet, a.skip {
  --dh-label: #1D1D1F; --dh-label-2: #6E6E73; --dh-label-3: #86868B;
  --dh-fill: rgba(118, 118, 128, 0.12); --dh-fill-2: rgba(118, 118, 128, 0.2);
  --dh-blue: #007AFF; --dh-blue-press: #0062CC;
  --dh-glass: rgba(250, 250, 252, 0.72); --dh-glass-rim: rgba(255, 255, 255, 0.9);
  --dh-glass-shadow: 0 8px 28px rgba(0, 0, 0, 0.1), 0 1px 4px rgba(0, 0, 0, 0.06);
  --dh-ease: cubic-bezier(0.22, 1, 0.36, 1);
  --blue: var(--dh-blue); /* the logo dot */
  font: 400 17px/1.47 -apple-system, BlinkMacSystemFont, "SF Pro Text", "SF Pro Display", "Helvetica Neue", Helvetica, Arial, system-ui, sans-serif;
  letter-spacing: -0.012em; -webkit-font-smoothing: antialiased; color: var(--dh-label); box-sizing: border-box;
}
[data-theme="dark"] header.nav, [data-theme="dark"] nav.menu-sheet, [data-theme="dark"] a.skip {
  --dh-label: #F5F5F7; --dh-label-2: #A1A1A6; --dh-label-3: #6E6E73;
  --dh-fill: rgba(118, 118, 128, 0.24); --dh-fill-2: rgba(118, 118, 128, 0.36);
  --dh-blue: #0A84FF; --dh-blue-press: #3D9BFF;
  --dh-glass: rgba(28, 28, 30, 0.7); --dh-glass-rim: rgba(255, 255, 255, 0.12);
  --dh-glass-shadow: 0 8px 28px rgba(0, 0, 0, 0.5), 0 1px 4px rgba(0, 0, 0, 0.3);
}
header.nav *, nav.menu-sheet * { box-sizing: border-box; }
header.nav a, nav.menu-sheet a { color: inherit; text-decoration: none; }
header.nav button { margin: 0; padding: 0; border: 0; background: none; color: inherit; font: inherit; cursor: pointer; }
header.nav :focus-visible, nav.menu-sheet :focus-visible { outline: 3px solid color-mix(in srgb, var(--dh-blue) 55%, transparent); outline-offset: 2px; border-radius: 8px; }

a.skip { position: absolute; left: 12px; top: -60px; z-index: 1000; padding: 8px 14px; border-radius: 10px; background: var(--dh-blue); color: #fff; text-decoration: none; }
a.skip:focus { top: 12px; }

header.nav { position: fixed; top: 12px; left: 50%; translate: -50% 0; transform: none; z-index: 900; width: min(1000px, 100% - 24px); height: 56px; margin: 0;
  padding: 0 8px 0 14px; border-radius: 28px; display: flex; align-items: center; gap: 12px;
  background: var(--dh-glass); border: 1px solid var(--dh-glass-rim); box-shadow: var(--dh-glass-shadow);
  backdrop-filter: blur(22px) saturate(180%); -webkit-backdrop-filter: blur(22px) saturate(180%); }
header.nav .nav-brand { display: flex; align-items: center; gap: 6px; font-weight: 600; font-size: 17px; white-space: nowrap; color: var(--dh-label); }
header.nav .brand-mark { display: block; width: 30px; height: 30px; min-width: 0; margin: 0 0 0 -4px; padding: 0; flex: 0 0 auto;
  border-radius: 0; background: none; box-shadow: none; border: 0; color: var(--dh-label); }
header.nav .nav-links { display: flex; gap: 4px; margin: 0 0 0 auto; }
header.nav .nav-links a { padding: 7px 13px; border-radius: 18px; font-size: 15px; color: var(--dh-label-2); transition: background .2s, color .2s; }
header.nav .nav-links a:hover { background: var(--dh-fill); color: var(--dh-label); }
header.nav .nav-links a[aria-current] { color: var(--dh-label); background: var(--dh-fill); font-weight: 500; }
header.nav .nav-actions { display: flex; align-items: center; gap: 6px; margin-left: 0; }
header.nav .icon-btn { width: 40px; height: 40px; border-radius: 50%; display: grid; place-items: center; color: var(--dh-label); }
header.nav .icon-btn:hover { background: var(--dh-fill); }
header.nav .icon-btn svg { width: 21px; height: 21px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
[data-theme="light"] header.nav .i-sun, [data-theme="dark"] header.nav .i-moon, html:not([data-theme]) header.nav .i-sun { display: none; }
header.nav .menu-btn { display: none; }
header.nav .btn, nav.menu-sheet .btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; white-space: nowrap; border-radius: 24px; font-weight: 500;
  background: var(--dh-blue); color: #fff; transition: background .2s, transform .15s; text-decoration: none; }
header.nav .btn:hover, nav.menu-sheet .btn:hover { background: var(--dh-blue-press); }
header.nav .btn:active, nav.menu-sheet .btn:active { transform: scale(.98); }
header.nav .btn-sm { min-height: 38px; padding: 0 16px; font-size: 15px; }
nav.menu-sheet .btn { width: 100%; min-height: 48px; margin-top: 6px; padding: 0 24px; font-size: 17px; justify-content: center; }

nav.menu-sheet { position: fixed; top: 76px; left: 12px; right: 12px; z-index: 899; margin: 0; padding: 8px; border-radius: 22px;
  background: var(--dh-glass); border: 1px solid var(--dh-glass-rim); box-shadow: var(--dh-glass-shadow);
  backdrop-filter: blur(22px) saturate(180%); -webkit-backdrop-filter: blur(22px) saturate(180%);
  opacity: 0; transform: translateY(-8px) scale(.98); pointer-events: none; transition: opacity .25s var(--dh-ease), transform .3s var(--dh-ease); }
nav.menu-sheet.is-open { opacity: 1; transform: none; pointer-events: auto; }
nav.menu-sheet a:not(.btn) { display: flex; align-items: center; justify-content: space-between; padding: 14px; border-radius: 14px; font-size: 17px; color: var(--dh-label); }
nav.menu-sheet a:not(.btn):hover, nav.menu-sheet a[aria-current] { background: var(--dh-fill); }
nav.menu-sheet a:not(.btn)::after { content: "›"; color: var(--dh-label-3); font-size: 20px; }

@media (max-width: 980px) { header.nav .nav-links a { padding: 7px 9px; font-size: 14px; } }
@media (max-width: 720px) {
  header.nav { height: 52px; padding-left: 12px; }
  header.nav .nav-links, header.nav .nav-actions .btn { display: none; }
  header.nav .nav-actions { margin-left: auto; }
  header.nav .menu-btn { display: grid; }
  nav.menu-sheet { top: 72px; }
}
@media (prefers-reduced-motion: reduce) { nav.menu-sheet { transition: none; } }