/* Qiaomu Clipper site: direction B "原生" (see DESIGN.md).
   Cool white canvas, near-black ink, grey rings instead of borders, lucide icons on grey tiles.
   The highlighter yellow appears only as the one marked phrase; amber lives in the logo's bead. */

:root {
  color-scheme: light;
  --bg: #f7f8fa; --bg-2: #eef0f4; --card: #ffffff; --surface: #fafafa; --tile: #f2f3f5;
  --ink: #171717; --ink-hover: #333333; --text: #4d4d4d; --muted: #666666; --faint: #808080;
  --ring: #ebebeb; --ring-2: #dcdee3;
  --accent: #ffb020; --highlight: #fff36b;
  --ring-shadow: 0 0 0 1px rgb(0 0 0 / 8%);
  --sh-card: 0 0 0 1px rgb(0 0 0 / 8%), 0 2px 2px rgb(0 0 0 / 4%), 0 8px 8px -8px rgb(0 0 0 / 4%);
  --sh-window: 0 0 0 1px rgb(0 0 0 / 8%), 0 2px 4px rgb(0 0 0 / 6%), 0 40px 80px -24px rgb(23 23 23 / 28%);
  --r-s: 10px; --r-m: 14px; --r-l: 18px;
  --font: -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  --container: 1120px; --gutter: 32px;
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
}

/* Chinese headings: Noto Serif SC Bold (SIL OFL), cut to the characters the headings use and self-hosted. */
@font-face { font-family: "Noto Serif SC Headline"; src: url("/fonts/headline.woff2") format("woff2"); font-weight: 700; font-style: normal; font-display: swap; }

*, *::before, *::after { box-sizing: border-box; }
html, body { overflow-x: clip; }
html { scroll-padding-top: 88px; scroll-behavior: smooth; }
body { margin: 0; background: linear-gradient(180deg, var(--bg) 0, var(--bg-2) 100%) fixed; color: var(--text); font-family: var(--font); font-size: 1.0625rem; line-height: 1.7; -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility; }
img { max-width: 100%; height: auto; display: block; }
svg { display: block; }
a { color: inherit; text-decoration-color: var(--ring-2); text-underline-offset: 0.18em; }
a:hover { text-decoration-color: var(--ink); }
p { margin: 0; text-wrap: pretty; }
h1, h2, h3 { margin: 0; font-family: var(--font); font-weight: 700; color: var(--ink); line-height: 1.2; letter-spacing: 0; text-wrap: balance; overflow-wrap: break-word; min-width: 0; }
:focus-visible { outline: 2px solid var(--ink); outline-offset: 3px; border-radius: 6px; }
::selection { background: color-mix(in srgb, var(--accent) 45%, transparent); }
mark { background: var(--highlight); color: inherit; padding: 0.05em 0.14em; border-radius: 3px; -webkit-box-decoration-break: clone; box-decoration-break: clone; }
kbd { display: inline-block; padding: 0 0.6em; min-width: 2em; text-align: center; border-radius: 8px; background: var(--card); box-shadow: var(--ring-shadow), 0 1px 0 rgb(0 0 0 / 6%); color: var(--ink); font-family: var(--font); font-weight: 600; font-size: 0.92em; line-height: 1.75; }
[hidden] { display: none !important; }

html[lang^="zh"] :is(.hero h1, .page-head h1, .section-title, .block-text h3, .card h3, .principles-panel h3, .edition h3, .feature-text h2, .agent-head h3) { font-family: "Noto Serif SC Headline", "Songti SC", "Noto Serif CJK SC", serif; font-weight: 700; font-synthesis: none; letter-spacing: 0.03em; }
html[lang^="zh"] .hero h1 { font-size: clamp(3rem, 7vw, 5.5rem); line-height: 1.15; }

.container { width: 100%; max-width: var(--container); margin-inline: auto; padding-inline: var(--gutter); }
.skip { position: absolute; left: 16px; top: 16px; z-index: 600; padding: 8px 16px; border-radius: var(--r-s); background: var(--ink); color: var(--card); transform: translateY(-200%); }
.skip:focus-visible { transform: none; }
.section-title { font-size: clamp(1.875rem, 3.4vw, 2.75rem); text-align: center; margin-bottom: 56px; }
.lead { font-size: 1.25rem; line-height: 1.65; color: var(--text); }

/* ---------- icons ---------- */
.mark-icon { display: inline-flex; align-items: center; justify-content: center; width: 40px; height: 40px; border-radius: 12px; background: var(--tile); color: var(--ink); }

/* icon tile sitting on the canvas gets a white face and a ring */
.block-text .mark-icon, .feature-text .mark-icon { background: var(--card); box-shadow: var(--ring-shadow); }

/* ---------- buttons: near-black primary, white secondary with a grey ring ---------- */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 44px; padding-inline: 20px; border: 0; border-radius: var(--r-s); background: var(--ink); color: var(--card); font-family: var(--font); font-weight: 500; font-size: 0.9375rem; line-height: 1.2; text-decoration: none; white-space: nowrap; cursor: pointer; transition: transform 180ms var(--ease), background-color 180ms var(--ease), box-shadow 180ms var(--ease); }
.btn:hover { background: var(--ink-hover); }
.btn:active { transform: translateY(1px); }
.btn:focus-visible { outline: 2px solid var(--ink); outline-offset: 2px; }
.btn:disabled, .btn[aria-disabled="true"] { opacity: 0.5; cursor: not-allowed; transform: none; }
.btn--secondary { background: var(--card); color: var(--ink); box-shadow: 0 0 0 1px var(--ring); }
.btn--secondary:hover { background: var(--surface); box-shadow: 0 0 0 1px var(--ring-2); }
.btn--sm { min-height: 36px; padding-inline: 14px; font-size: 0.875rem; }
.actions { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; }
.icon-btn { display: inline-flex; align-items: center; justify-content: center; width: 40px; height: 40px; padding: 0; border: 0; border-radius: var(--r-s); background: none; color: var(--muted); cursor: pointer; transition: background-color 180ms var(--ease), color 180ms var(--ease); }
.icon-btn:hover { background: var(--tile); color: var(--ink); }
.icon-btn:active { transform: translateY(1px); }
.icon-btn:disabled { opacity: 0.5; cursor: not-allowed; }

/* ---------- nav ---------- */
.site-nav { position: sticky; top: 0; z-index: 300; background: color-mix(in srgb, var(--bg) 82%, transparent); backdrop-filter: saturate(1.6) blur(16px); -webkit-backdrop-filter: saturate(1.6) blur(16px); box-shadow: 0 1px 0 rgb(0 0 0 / 6%); }
.nav-inner { display: flex; align-items: center; gap: 24px; min-height: 60px; }
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; font-weight: 700; font-size: 1.0625rem; color: var(--ink); white-space: nowrap; }
.brand img { border-radius: 8px; }
.nav-links { display: flex; align-items: center; gap: 2px; margin-inline-start: 12px; }
.nav-links a { padding: 6px 12px; border-radius: 8px; color: var(--muted); font-size: 0.9375rem; text-decoration: none; transition: background-color 180ms var(--ease), color 180ms var(--ease); }
.nav-links a:hover { background: var(--tile); color: var(--ink); }
.nav-links a[aria-current="page"] { color: var(--ink); }
.nav-tools { display: flex; align-items: center; gap: 2px; margin-inline-start: auto; }
.lang-switch { margin-inline: 4px 10px; padding: 6px 10px; border-radius: 8px; color: var(--muted); font-size: 0.9375rem; text-decoration: none; transition: background-color 180ms var(--ease), color 180ms var(--ease); }
.lang-switch:hover { background: var(--tile); color: var(--ink); }

/* ---------- hero ---------- */
.hero { padding-top: 88px; text-align: center; }
.hero-text { display: grid; justify-items: center; gap: 20px; }
.hero h1 { font-size: clamp(2.75rem, 6.4vw, 4.75rem); line-height: 1.1; max-width: 13em; font-weight: 700; }
.hero .lead { max-width: 30em; font-size: 1.3125rem; color: var(--muted); }
.chips { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; }
.chip { display: inline-flex; align-items: center; gap: 8px; padding: 7px 14px 7px 10px; border-radius: 999px; background: var(--card); box-shadow: var(--ring-shadow); color: var(--ink); font-size: 0.9375rem; font-weight: 500; text-decoration: none; transition: background-color 180ms var(--ease); }
.chip:hover { background: var(--surface); }
.hero .actions { margin-top: 4px; }
.hero-meta { font-size: 0.875rem; color: var(--faint); }
.window { margin: 64px auto 0; max-width: 1040px; }
.window-bar { display: flex; align-items: center; gap: 7px; height: 36px; padding-inline: 14px; border-radius: var(--r-m) var(--r-m) 0 0; background: #f1f2f4; box-shadow: var(--ring-shadow); }
.window-bar i { display: block; width: 11px; height: 11px; border-radius: 50%; background: #d4d6da; }
.window img { width: 100%; height: auto; background: var(--card); box-shadow: var(--sh-window); }
.window figcaption { margin-top: 16px; font-size: 0.875rem; color: var(--faint); }

/* ---------- feature blocks ---------- */
.blocks { padding-block: 112px 24px; }
.block { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); gap: 72px; align-items: center; padding-block: 48px; }
.block:nth-of-type(even) { grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); }
.block:nth-of-type(even) .block-text { order: 2; }
.block-text { display: grid; gap: 14px; justify-items: start; }
.block-text h3 { font-size: clamp(1.625rem, 2.8vw, 2.25rem); max-width: 14em; }
.block-text p:not([class]) { font-size: 1.125rem; line-height: 1.75; max-width: 28em; color: var(--muted); }
.keyline { display: flex; align-items: center; gap: 12px; margin-top: 6px; font-size: 0.9688rem; color: var(--faint); }
.keyline kbd { font-size: 1.125rem; padding-inline: 0.75em; }
.visual { display: flex; align-items: center; justify-content: center; gap: 20px; padding: 36px; border-radius: 22px; background: var(--card); box-shadow: var(--sh-card); min-height: 360px; }
.visual img { width: 100%; height: auto; max-height: 480px; object-fit: contain; border-radius: 12px; box-shadow: var(--ring-shadow); background: var(--card); }
.visual--pair img { width: auto; max-width: 47%; }

/* ---------- cards ---------- */
.more { padding-block: 96px; }
.cards { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.card { display: grid; align-content: start; gap: 10px; height: 100%; padding: 28px; border-radius: var(--r-l); background: var(--card); text-decoration: none; color: var(--text); box-shadow: var(--sh-card); transition: transform 220ms var(--ease), box-shadow 220ms var(--ease); }
.card:hover { transform: translateY(-3px); box-shadow: 0 0 0 1px rgb(0 0 0 / 10%), 0 2px 4px rgb(0 0 0 / 5%), 0 16px 28px -12px rgb(0 0 0 / 14%); }
.card:active { transform: translateY(-1px); }
.card .mark-icon { margin-bottom: 6px; }
.card h3 { font-size: 1.1875rem; }
.card p { font-size: 0.9688rem; line-height: 1.7; color: var(--muted); }
.more-link { display: flex; justify-content: center; margin-top: 44px; }

/* ---------- principles ---------- */
.principles { padding-block: 40px; }
.principles-panel { padding: 56px; border-radius: 28px; background: var(--ink); color: #c7c7c7; }
.principles-panel ul { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 40px; }
.principles-panel h3 { margin-bottom: 10px; font-size: 1.375rem; color: var(--card); }
.principles-panel li p { font-size: 0.9688rem; line-height: 1.75; }
.principles-note { margin-top: 44px; padding-top: 24px; border-top: 1px solid rgb(255 255 255 / 14%); font-size: 0.875rem; color: #9a9a9a; max-width: 60em; }
.principles-note a { color: var(--card); }
.principles-panel :focus-visible { outline-color: var(--card); }

/* ---------- get ---------- */
.get { padding-block: 104px 96px; }
.editions { list-style: none; margin: 0; padding: 0; display: grid; gap: 14px; }
.editions--cards { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.edition { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 24px; align-items: center; padding: 24px 28px; border-radius: var(--r-l); background: var(--card); box-shadow: var(--sh-card); }
.edition--main { box-shadow: 0 0 0 2px var(--ink), 0 8px 24px -10px rgb(0 0 0 / 20%); }
.edition h3 { margin-bottom: 6px; font-size: 1.25rem; }
.edition p { font-size: 0.9688rem; line-height: 1.65; color: var(--muted); max-width: 32em; }
.editions--cards .edition { grid-template-columns: minmax(0, 1fr); align-content: space-between; gap: 28px; padding: 30px; }
.editions--cards .edition .btn { width: 100%; }
.agent { display: grid; grid-template-columns: minmax(0, 4fr) minmax(0, 8fr); gap: 48px; margin-top: 56px; padding: 36px; border-radius: var(--r-l); background: var(--card); box-shadow: var(--sh-card); align-items: start; }
.agent-head { display: grid; gap: 10px; }
.agent-head h3 { font-size: 1.375rem; }
.agent-head p { font-size: 0.9688rem; color: var(--muted); }
.agent-box { display: grid; gap: 14px; justify-items: start; min-width: 0; }
.agent-box pre { width: 100%; max-height: 220px; margin: 0; padding: 18px 20px; overflow: auto; border-radius: var(--r-m); background: var(--surface); box-shadow: inset 0 0 0 1px var(--ring); color: var(--ink); font: inherit; font-size: 0.9062rem; line-height: 1.75; white-space: pre-wrap; overflow-wrap: anywhere; }
.feature .agent { display: block; margin-top: 0; padding: 0; background: none; box-shadow: none; border-radius: 0; }

/* ---------- faq ---------- */
.faq-home { padding-block: 40px 120px; }
.faq-narrow { max-width: 860px; }
.qa-list { display: grid; gap: 10px; }
.qa { border-radius: var(--r-m); background: var(--card); box-shadow: var(--sh-card); }
.qa summary { display: flex; align-items: center; justify-content: space-between; gap: 20px; min-height: 64px; padding: 12px 22px; cursor: pointer; list-style: none; border-radius: var(--r-m); }
.qa summary::-webkit-details-marker { display: none; }
.qa summary:focus-visible { outline: 2px solid var(--ink); outline-offset: 2px; }
.qa summary h3 { font-size: 1.0625rem; font-weight: 600; max-width: none; }
.qa summary::after { content: "+"; flex: none; display: inline-flex; align-items: center; justify-content: center; width: 28px; height: 28px; border-radius: 50%; background: var(--tile); color: var(--ink); font-size: 1.25rem; line-height: 1; transition: transform 220ms var(--ease); }
.qa[open] summary::after { transform: rotate(45deg); }
.qa p { padding: 0 22px 22px; max-width: 44em; font-size: 0.9688rem; line-height: 1.85; color: var(--muted); }
.faq-full { padding-top: 0; }

/* ---------- inner pages ---------- */
.page-head { padding-block: 88px 48px; text-align: center; }
.page-head .container { display: grid; gap: 14px; justify-items: center; }
.page-head h1 { font-size: clamp(2.25rem, 4.6vw, 3.5rem); }
.page-head .lead { max-width: 32em; color: var(--muted); }
.version { font-size: 0.875rem; color: var(--faint); }
.feature { padding-block: 8px; }
.feature:last-of-type { padding-bottom: 0; }
.feature-card { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 56px; align-items: center; padding: 44px; border-radius: 22px; background: var(--card); box-shadow: var(--sh-card); }
.feature-card--text { grid-template-columns: minmax(0, 1fr); }
.feature-card--text .feature-text { max-width: 52em; }
.feature-text { display: grid; gap: 14px; justify-items: start; align-content: start; }
.feature-text h2 { font-size: clamp(1.625rem, 2.8vw, 2.125rem); max-width: none; }
.feature-text h3 { margin-top: 14px; font-size: 1.25rem; }
.feature-text .lead { font-size: 1.125rem; color: var(--muted); }
.details { display: grid; gap: 12px; margin-top: 2px; }
.details p { font-size: 1rem; line-height: 1.85; max-width: 40em; }
.shot { margin: 0; display: flex; align-items: center; justify-content: center; padding: 24px; border-radius: var(--r-l); background: var(--surface); box-shadow: inset 0 0 0 1px var(--ring); min-height: 300px; }
.shot img { width: 100%; height: auto; max-height: 420px; object-fit: contain; border-radius: 10px; box-shadow: var(--ring-shadow); background: var(--card); }
.points { margin: 0; padding-inline-start: 22px; display: grid; gap: 10px; font-size: 1rem; }
.note { max-width: 44em; font-size: 0.9062rem; color: var(--faint); }
.keys { width: 100%; border-collapse: collapse; margin-top: 4px; }
.keys th, .keys td { padding: 14px 0; text-align: start; border-top: 1px solid var(--ring); font-size: 1rem; font-weight: 400; }
.keys th { width: 9rem; }
.keys tr:last-child th, .keys tr:last-child td { border-bottom: 1px solid var(--ring); }
.editions--flat .edition { box-shadow: inset 0 0 0 1px var(--ring); background: var(--surface); }
.editions--flat .edition--main { box-shadow: inset 0 0 0 2px var(--ink); }
.close { padding-block: 88px 112px; }
.close-inner { display: grid; justify-items: center; gap: 24px; }
.close-inner .section-title { margin-bottom: 0; }

/* ---------- footer ---------- */
.site-foot { padding-block: 72px 36px; background: var(--card); box-shadow: 0 -1px 0 rgb(0 0 0 / 6%); }
.foot-top { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); gap: 48px; }
.foot-mast { display: flex; align-items: center; gap: 14px; align-self: start; }
.foot-mast img { border-radius: 12px; }
.foot-name { font-weight: 700; font-size: 1.25rem; color: var(--ink); line-height: 1.2; }
.foot-tag { font-size: 0.9375rem; color: var(--muted); }
.foot-cols { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 32px; }
.foot-title { margin: 0 0 12px; font-weight: 600; font-size: 0.875rem; color: var(--faint); }
.foot-col ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 4px; }
.foot-col a { display: inline-block; padding-block: 4px; color: var(--ink); text-decoration: none; font-size: 0.9688rem; }
.foot-col a:hover { text-decoration: underline; text-decoration-color: var(--ink); }
.foot-base { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 16px; margin-top: 56px; padding-top: 24px; border-top: 1px solid var(--ring); font-size: 0.875rem; color: var(--faint); }
.foot-base p { max-width: 48em; }
.foot-icons { display: flex; gap: 2px; }

/* ---------- modals ---------- */
.modal { width: min(24rem, calc(100% - 32px)); padding: 0; border: 0; border-radius: 20px; background: var(--card); color: var(--text); box-shadow: 0 0 0 1px rgb(0 0 0 / 8%), 0 30px 80px -20px rgb(0 0 0 / 40%); }
.modal::backdrop { background: rgb(23 23 23 / 40%); backdrop-filter: blur(4px); }
.modal-bar { display: flex; align-items: center; justify-content: space-between; gap: 16px; margin: 0; padding: 16px 12px 6px 24px; }
.modal-bar h2 { font-size: 1.1875rem; max-width: none; }
.modal-body { display: grid; gap: 14px; justify-items: center; padding: 8px 24px 28px; text-align: center; }
.modal-body img { width: 240px; height: 240px; object-fit: contain; border-radius: var(--r-m); }
.modal-body p { font-size: 0.9688rem; color: var(--muted); }
.modal-links { display: flex; flex-wrap: wrap; justify-content: center; gap: 4px 16px; font-size: 0.875rem; }

/* ---------- small screens ---------- */
@media (max-width: 62rem) {
  :root { --gutter: 24px; }
  .block, .block:nth-of-type(even) { grid-template-columns: minmax(0, 1fr); gap: 28px; padding-block: 36px; }
  .block:nth-of-type(even) .block-text { order: 0; }
  .visual { padding: 22px; min-height: 0; }
  .cards { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .principles-panel { padding: 36px 28px; }
  .principles-panel ul { grid-template-columns: minmax(0, 1fr); gap: 28px; }
  .editions--cards { grid-template-columns: minmax(0, 1fr); }
  .agent, .foot-top, .feature-card { grid-template-columns: minmax(0, 1fr); gap: 28px; }
  .feature-card { padding: 30px 22px; }
  .agent { padding: 26px 22px; }
  .nav-links { margin-inline-start: 0; }
}
@media (max-width: 46rem) {
  :root { --gutter: 16px; }
  .nav-inner { flex-wrap: wrap; gap: 2px 8px; min-height: 0; padding-block: 8px; }
  .nav-links { order: 3; width: 100%; overflow-x: auto; padding-bottom: 4px; }
  .nav-tools .btn { display: none; }
  .hero { padding-top: 40px; }
  .hero .lead { font-size: 1.125rem; }
  .window { margin-top: 44px; }
  .blocks, .more, .get { padding-block: 56px; }
  .section-title { margin-bottom: 32px; }
  .cards { grid-template-columns: minmax(0, 1fr); }
  .edition { grid-template-columns: minmax(0, 1fr); gap: 16px; padding: 20px; }
  .visual--pair { flex-direction: column; }
  .visual--pair img { max-width: 100%; }
  .foot-cols { grid-template-columns: minmax(0, 1fr); }
  .page-head { padding-block: 52px 28px; }
  .qa summary { padding-inline: 16px; }
  .qa p { padding-inline: 16px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .btn, .icon-btn, .card, .chip, .qa summary::after, .nav-links a, .lang-switch { transition: none; }
}