/* H-DXC-1 handbook stylesheet — DiffuseXrayCalibration.
   Light and dark mode, phone-first (16 px side gutter), no horizontal scroll. */

/* ---- bilingual switch (skill 0.5.0, pasted unchanged) ---- */
html[data-lang="en"] .l-zh,
html:not([data-lang="en"]) .l-en { display: none !important; }

.lang-toggle {
  font: inherit; font-size: 0.9rem; padding: 0.3rem 0.8rem; min-height: 44px; min-width: 44px;
  border: 1px solid currentColor; border-radius: 999px; background: transparent; color: inherit; cursor: pointer;
}
.lang-toggle:focus-visible { outline: 2px solid currentColor; outline-offset: 2px; }

/* ---- theme ---- */
:root {
  --bg: #f6f7f9; --panel: #ffffff; --ink: #1a1d21; --muted: #5b6470;
  --line: #d8dde3; --accent: #0b5fa5; --accent-soft: #e8f1fa;
  --ok: #0f7b3d; --warn: #b45309; --bad: #b3261e; --code-bg: #eef1f4;
  --shadow: 0 1px 2px rgba(16,24,40,.06), 0 1px 3px rgba(16,24,40,.10);
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}
html[data-theme="dark"] {
  --bg: #14171a; --panel: #1b1f24; --ink: #e6e9ed; --muted: #a3adb9;
  --line: #2c333b; --accent: #6cb2f0; --accent-soft: #1d2b3a;
  --ok: #58c08a; --warn: #e0a35a; --bad: #f08a82; --code-bg: #22272e;
  --shadow: 0 1px 2px rgba(0,0,0,.4), 0 1px 3px rgba(0,0,0,.5);
}
@media (prefers-color-scheme: dark) {
  html:not([data-theme="light"]) {
    --bg: #14171a; --panel: #1b1f24; --ink: #e6e9ed; --muted: #a3adb9;
    --line: #2c333b; --accent: #6cb2f0; --accent-soft: #1d2b3a;
    --ok: #58c08a; --warn: #e0a35a; --bad: #f08a82; --code-bg: #22272e;
    --shadow: 0 1px 2px rgba(0,0,0,.4), 0 1px 3px rgba(0,0,0,.5);
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font-family: var(--sans); font-size: 16px; line-height: 1.62;
  overflow-x: hidden;
}
img, svg, figure, table, pre { max-width: 100%; }
img { height: auto; }

/* ---- layout ---- */
.wrap { max-width: 1180px; margin: 0 auto; padding: 0 16px; }
header.site {
  position: sticky; top: 0; z-index: 20; background: var(--panel);
  border-bottom: 1px solid var(--line); box-shadow: var(--shadow);
}
header.site .bar {
  max-width: 1180px; margin: 0 auto; padding: 8px 16px;
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
}
.brand { font-weight: 700; font-size: 1.02rem; letter-spacing: .2px; text-decoration: none; color: var(--ink); }
.brand small { font-weight: 500; color: var(--muted); font-size: .78rem; margin-left: 6px; }
header.site .spacer { flex: 1 1 auto; }
button.theme {
  font: inherit; font-size: .85rem; min-height: 44px; min-width: 44px; padding: .3rem .7rem;
  border: 1px solid var(--line); border-radius: 999px; background: var(--bg); color: var(--ink); cursor: pointer;
}
button.theme:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

nav.toc { background: var(--panel); border-bottom: 1px solid var(--line); }
nav.toc details { max-width: 1180px; margin: 0 auto; padding: 0 16px; }
nav.toc summary {
  cursor: pointer; padding: 8px 0; font-size: .9rem; color: var(--muted); list-style: none;
}
nav.toc summary::-webkit-details-marker { display: none; }
nav.toc summary::before { content: "☰ "; }
nav.toc ol { margin: 0 0 10px; padding-left: 20px; }
nav.toc a { color: var(--accent); text-decoration: none; }
nav.toc a:hover { text-decoration: underline; }
nav.toc a.here { font-weight: 700; }
nav.toc ol { display: flex; flex-wrap: wrap; gap: 2px 14px; list-style: none; padding-left: 0; }

main { padding: 18px 0 60px; }
footer.site {
  border-top: 1px solid var(--line); background: var(--panel);
  padding: 18px 0; color: var(--muted); font-size: .85rem;
}

/* ---- headings & text ---- */
h1 { font-size: 1.55rem; line-height: 1.25; margin: 18px 0 10px; }
h2 { font-size: 1.22rem; line-height: 1.3; margin: 26px 0 8px; padding-bottom: 4px; border-bottom: 1px solid var(--line); }
h3 { font-size: 1.03rem; margin: 18px 0 6px; }
h4 { font-size: .95rem; margin: 14px 0 4px; color: var(--muted); }
p { margin: 8px 0; }
ul, ol { margin: 8px 0 8px 22px; padding: 0; }
li { margin: 4px 0; }
a { color: var(--accent); }
code, kbd, samp {
  font-family: var(--mono); font-size: .86em; background: var(--code-bg);
  padding: .1em .35em; border-radius: 4px; word-break: break-word;
}
pre {
  background: var(--code-bg); border: 1px solid var(--line); border-radius: 8px;
  padding: 10px 12px; overflow-x: auto; font-size: .82rem; line-height: 1.5;
}
pre code { background: none; padding: 0; }
blockquote { margin: 10px 0; padding: 6px 14px; border-left: 3px solid var(--accent); color: var(--muted); background: var(--accent-soft); border-radius: 0 8px 8px 0; }
hr { border: none; border-top: 1px solid var(--line); margin: 22px 0; }

/* ---- cards, tables, figures ---- */
.card {
  background: var(--panel); border: 1px solid var(--line); border-radius: 12px;
  padding: 14px 16px; margin: 14px 0; box-shadow: var(--shadow);
}
.card > h2, .card > h3 { margin-top: 0; }
.grid2 { display: grid; grid-template-columns: 1fr; gap: 14px; }
@media (min-width: 860px) { .grid2 { grid-template-columns: 1fr 1fr; } }

table { border-collapse: collapse; width: 100%; margin: 10px 0; font-size: .88rem; }
th, td { border: 1px solid var(--line); padding: 6px 8px; text-align: left; vertical-align: top; }
th { background: var(--code-bg); font-weight: 600; }
td.num, th.num { text-align: right; font-variant-numeric: tabular-nums; }
.tw { overflow-x: auto; -webkit-overflow-scrolling: touch; }

figure { margin: 14px 0; }
figure img { display: block; width: 100%; border: 1px solid var(--line); border-radius: 10px; background: var(--panel); }
figcaption { font-size: .84rem; color: var(--muted); margin-top: 6px; }

.src {
  font-size: .78rem; color: var(--muted); margin: 4px 0 0;
  border-left: 3px solid var(--line); padding-left: 8px;
}
.src code { font-size: .95em; }

.tag { display: inline-block; font-size: .74rem; padding: 1px 8px; border-radius: 999px; border: 1px solid var(--line); background: var(--code-bg); color: var(--muted); white-space: nowrap; }
.tag.ok { color: var(--ok); border-color: var(--ok); }
.tag.warn { color: var(--warn); border-color: var(--warn); }
.tag.bad { color: var(--bad); border-color: var(--bad); }
.tag.info { color: var(--accent); border-color: var(--accent); }

.banner {
  border: 1px solid var(--warn); background: color-mix(in srgb, var(--warn) 10%, var(--panel));
  border-radius: 10px; padding: 10px 14px; margin: 14px 0; font-size: .9rem;
}
.banner.info { border-color: var(--accent); background: var(--accent-soft); }

.katex-display { overflow-x: auto; overflow-y: hidden; padding: 4px 0; }
.katex { font-size: 1.05em; }

/* ---- animations ---- */
.anim { border: 1px solid var(--line); border-radius: 12px; background: var(--panel); padding: 10px; margin: 14px 0; box-shadow: var(--shadow); }
.anim .stage { display: block; width: 100%; }
.anim .ctrl { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; margin-top: 8px; font-size: .85rem; }
.anim .ctrl button {
  font: inherit; font-size: .82rem; min-height: 36px; padding: .25rem .8rem;
  border: 1px solid var(--line); border-radius: 8px; background: var(--bg); color: var(--ink); cursor: pointer;
}
.anim .ctrl button[aria-pressed="true"] { background: var(--accent); color: #fff; border-color: var(--accent); }
.anim .readout { font-family: var(--mono); font-size: .82rem; color: var(--muted); }

/* ---- home-page compact mode (the workbench must fit one screen at 1280x800) ---- */
.home { font-size: 15px; line-height: 1.5; }
.home h1 { font-size: 1.3rem; margin: 10px 0 6px; }
.home h2 { font-size: 1.08rem; margin: 10px 0 4px; }
.home .card { padding: 8px 10px; margin: 6px 0; }
.home figure { margin: 8px 0; }
.home figcaption { font-size: .78rem; }
.home .src { font-size: .72rem; margin: 2px 0 0; }
.home table { font-size: .82rem; margin: 6px 0; }
.home th, .home td { padding: 3px 5px; }
.home .banner { padding: 6px 10px; margin: 8px 0; font-size: .84rem; }
.home p { margin: 6px 0; }
.home main { padding-top: 4px; }
.home header.site .bar { padding: 4px 16px; }
.home nav.toc summary { padding: 4px 0; }
.home h1 { margin: 6px 0 4px; }

/* ---- print ---- */
@media print {
  header.site, nav.toc, .anim .ctrl, button { display: none !important; }
  body { background: #fff; color: #000; }
  .card, .anim { break-inside: avoid; box-shadow: none; }
}