/* mcp-surface playground. Same tokens as the homepage and the neuronet-arena
   demo: near-black ground, amber accent, teal secondary, IBM Plex. */

/* ---- tokens (§7.1). Demo pages carry a copy of this block (§7.11). ---- */
/* Tokens for brettadams0.github.io. Dark only. Demo pages copy this :root block (spec 7.11). */
:root {
  color-scheme: dark;

  /* Colour: existing values, unchanged */
  --bg: #0b0f14;
  --bg-2: #0e141b;
  --surface: #131a22;
  --surface-2: #18212b;
  --border: #222c38;
  --border-strong: #2f3b4a;
  --text: #e7ecf2;
  --soft: #c4ccd6;
  --muted: #8695a7;
  --faint: #5a6878;        /* list markers and control edges only; never words (3.37:1 on --bg) */
  --amber: #ffb454;
  --amber-hi: #ffc97f;
  --teal: #4fd6c4;
  --red: #ef6a5f;
  --good: #3ccf6e;

  /* Colour: new */
  --dim: #7b8a9c;          /* words that used --faint; >= 4.61:1 on every background */
  --good-text: #9fe3b7;    /* text on green washes: status line, Live demo badge */
  --on-amber: #1a1206;     /* text on --amber / --amber-hi fills */
  --term: var(--bg-2);     /* terminal and code panels */
  --focus: var(--amber);
  --amber-line: rgba(255, 180, 84, 0.5);
  --amber-wash: rgba(255, 180, 84, 0.1);
  --good-line: rgba(60, 207, 110, 0.3);
  --good-wash: rgba(60, 207, 110, 0.07);

  /* Type */
  --sans: "IBM Plex Sans", "IBM Plex Sans Fallback", -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  --mono: "IBM Plex Mono", "IBM Plex Mono Fallback", ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --fs-xs: 0.75rem;                            /* 12px */
  --fs-sm: 0.875rem;                           /* 14px */
  --fs-base: 1rem;                             /* 16px */
  --fs-md: 1.0625rem;                          /* 17px */
  --fs-lg: 1.1875rem;                          /* 19px */
  --fs-xl: 1.375rem;                           /* 22px */
  --fs-2xl: clamp(2rem, 5vw, 2.75rem);         /* 32–44px */
  --fs-3xl: clamp(1.625rem, 4.5vw, 3rem);      /* 26–48px */
  --fs-display: clamp(2.75rem, 6vw, 4.5rem);   /* 44–72px */
  --lh-tight: 1.1;
  --lh-snug: 1.3;
  --lh-base: 1.6;
  --lh-loose: 1.75;
  --tracking-tight: -0.03em;
  --tracking-caps: 0.08em;

  /* Space (4 px base) */
  --space-1: 0.25rem;   /* 4 */
  --space-2: 0.5rem;    /* 8 */
  --space-3: 0.75rem;   /* 12 */
  --space-4: 1rem;      /* 16 */
  --space-5: 1.25rem;   /* 20 */
  --space-6: 1.5rem;    /* 24 */
  --space-7: 2rem;      /* 32 */
  --space-8: 3rem;      /* 48 */
  --space-9: 4rem;      /* 64 */
  --space-10: 5.5rem;   /* 88 */

  /* Layout */
  --container: 1200px;
  --container-demo: 1320px;
  --container-post: 760px;
  --gutter: 24px;
  --header-h: 56px;

  /* Shape and layers */
  --radius-sm: 6px;
  --radius: 10px;
  --radius-pill: 999px;
  --shadow-focus: 0 0 0 3px var(--bg), 0 0 0 5px var(--focus);
  --z-header: 10;
  --z-skip: 20;

  /* Motion (section 9) */
  --dur-fast: 120ms;
  --dur: 180ms;
  --dur-slow: 240ms;
  --ease-out: cubic-bezier(0.2, 0, 0, 1);
  --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);
}

@media (max-width: 640px) {
  :root { --gutter: 16px; }
}

@media (prefers-reduced-motion: reduce) {
  :root { --dur-fast: 0ms; --dur: 0ms; --dur-slow: 0ms; }
}

/* IBM Plex, self-hosted (7.5). Files are Google Fonts' latin subsets, byte for byte. Licence: ../fonts/OFL.txt */
@font-face {
  font-family: "IBM Plex Sans";
  font-style: normal;
  font-weight: 400 700;
  font-display: swap;
  src: url("/assets/fonts/ibm-plex-sans-latin-var.woff2") format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
@font-face {
  font-family: "IBM Plex Mono";
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url("/assets/fonts/ibm-plex-mono-latin-400.woff2") format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
@font-face {
  font-family: "IBM Plex Mono";
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url("/assets/fonts/ibm-plex-mono-latin-500.woff2") format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
@font-face {
  font-family: "IBM Plex Mono";
  font-style: normal;
  font-weight: 600;
  font-display: swap;
  src: url("/assets/fonts/ibm-plex-mono-latin-600.woff2") format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

/* Metric-matched fallbacks: shown until Plex arrives, sized so no line re-wraps on swap (7.5). */
@font-face {
  font-family: "IBM Plex Sans Fallback";
  src: local("Arial"), local("ArialMT"), local("Liberation Sans"), local("Helvetica");
  size-adjust: 100.3%;
  ascent-override: 102.2%;
  descent-override: 27.4%;
  line-gap-override: 0%;
}
@font-face {
  font-family: "IBM Plex Sans Fallback";
  font-weight: 600 700;
  src: local("Arial Bold"), local("Arial-BoldMT"), local("Liberation Sans Bold"), local("Helvetica Bold");
  size-adjust: 98%;
  ascent-override: 104.6%;
  descent-override: 28.1%;
  line-gap-override: 0%;
}
@font-face {
  font-family: "IBM Plex Mono Fallback";
  src: local("Courier New"), local("CourierNewPSMT"), local("Liberation Mono");
  size-adjust: 100%;
  ascent-override: 102.5%;
  descent-override: 27.5%;
  line-gap-override: 0%;
}
/* ---- end tokens ---- */

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--text); font: 15px/1.55 var(--sans); }
a { color: var(--amber); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { color: var(--amber-hi); }
code { font-family: var(--mono); font-size: 0.9em; }

.wrap { max-width: var(--container-demo); margin: 0 auto; padding: 0 var(--gutter); }

.intro { padding: 28px 0 20px; max-width: 860px; }
h1 { margin: 0 0 8px; font: 600 30px/1.2 var(--mono); letter-spacing: -0.01em; }
.lede { margin: 0; color: var(--soft); font-size: var(--fs-md); }

.layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 20px;
  align-items: start;
}

.card {
  display: flex;
  flex-direction: column;
  min-width: 0;
  padding: 16px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.card-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap; margin-bottom: 12px; }
.card h2 { margin: 0; font-size: 14px; font-weight: 600; }
.meta { color: var(--muted); font: 12px var(--mono); }

/* Segmented control, as in the neuronet-arena demo */
.seg { display: inline-flex; border: 1px solid var(--border-strong); border-radius: 7px; overflow: hidden; }
.seg button {
  padding: 5px 11px;
  border: 0;
  border-right: 1px solid var(--border-strong);
  background: transparent;
  color: var(--text);
  font: 500 13px var(--sans);
  cursor: pointer;
}
.seg button:last-child { border-right: 0; }
.seg button:hover { background: var(--surface-2); }
.seg button[aria-pressed="true"] { background: rgba(255, 180, 84, 0.12); color: var(--amber); }

/* Editor */
.editor {
  display: flex;
  height: 620px;
  background: var(--term);
  border: 1px solid var(--muted);
  border-radius: 8px;
  overflow: hidden;
}
.editor:focus-within { box-shadow: var(--shadow-focus); }
.gutter {
  margin: 0;
  padding: 12px 10px 12px 12px;
  min-width: 44px;
  overflow: hidden;
  color: var(--dim);
  text-align: right;
  font: 13px/1.6 var(--mono);
  user-select: none;
  border-right: 1px solid var(--border);
}
textarea {
  flex: 1;
  min-width: 0;
  margin: 0;
  padding: 12px;
  border: 0;
  outline: 0;
  resize: none;
  background: transparent;
  color: var(--text);
  font: 13px/1.6 var(--mono);
  tab-size: 2;
  white-space: pre;
  overflow: auto;
}
textarea[aria-invalid="true"] { box-shadow: inset 3px 0 0 var(--red); }
.parse { margin: 10px 0 0; color: var(--muted); font: 12px var(--mono); }
.parse.bad { color: var(--red); }

/* Report */
.failon { color: var(--muted); font: 12px var(--mono); display: inline-flex; align-items: center; gap: 8px; }
select {
  padding: 4px 8px;
  border: 1px solid var(--muted);
  border-radius: 6px;
  background: var(--surface-2);
  color: var(--text);
  font: 13px var(--mono);
}

.term {
  height: 620px;
  padding: 12px 14px;
  overflow: auto;
  background: var(--term);
  border: 1px solid var(--border);
  border-radius: 8px;
  font: 13px/1.6 var(--mono);
}
.term p { margin: 0; }
.cmd { margin-bottom: 12px !important; color: var(--text); overflow-wrap: anywhere; }
.prompt { color: var(--good); }
.line { overflow-wrap: anywhere; }
.dim { color: var(--muted); }
.tools { margin: 12px 0; padding-left: 16px; }
.tool-name { color: var(--teal); }
.ok { margin-top: 12px !important; color: var(--good); }
.findings { margin: 12px 0; display: grid; gap: 6px; }
.finding {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  column-gap: 10px;
  overflow-wrap: anywhere;
}
.finding .lvl { grid-row: span 3; font-weight: 600; }
.finding .subject { color: var(--text); font-weight: 600; }
.finding .msg { color: var(--soft); }
.finding .rule-tag { color: var(--dim); }
.lvl-error .lvl { color: var(--red); }
.lvl-warn .lvl { color: var(--amber); }
.lvl-info .lvl { color: var(--muted); }
.summary { margin-top: 12px !important; color: var(--muted); }

.verdict {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 12px;
  padding: 10px 12px;
  border-radius: 8px;
  font: 13px var(--mono);
  border: 1px solid var(--border);
}
.verdict b { font-weight: 600; }
.verdict.pass { color: var(--good); background: rgba(60, 207, 110, 0.07); border-color: rgba(60, 207, 110, 0.3); }
.verdict.fail { color: var(--red); background: rgba(239, 106, 95, 0.07); border-color: rgba(239, 106, 95, 0.3); }

/* Rules */
.rules-card { margin-top: 20px; }
.rules {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(290px, 100%), 1fr));   /* fits 320 px (reflow, SC 1.4.10) */
  gap: 8px;
}
.rule {
  position: relative;
  width: 100%;
  display: grid;
  grid-template-columns: minmax(44px, auto) minmax(0, 1fr);
  grid-template-rows: auto auto;
  column-gap: 10px;
  padding: 9px 36px 9px 10px;
  text-align: left;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  font: 13px var(--sans);
  cursor: pointer;
  transition: border-color var(--dur-fast) var(--ease-out), background-color var(--dur-fast) var(--ease-out);
}
.rule:hover { border-color: var(--border-strong); }
.rule-level { grid-row: span 2; font: 600 11px/1.9 var(--mono); text-transform: uppercase; color: var(--muted); }
.rule.lvl-error .rule-level { color: var(--red); }
.rule.lvl-warn .rule-level { color: var(--amber); }
.rule-id { font-size: 12px; color: var(--text); }
.rule-what { color: var(--muted); font-size: 12.5px; }
/* State in words and full-opacity colour, never opacity (§8.20 fix 5, §7.3) */
.rule.call-only .rule-id, .rule[aria-pressed="true"] .rule-id { color: var(--muted); }
.rule.call-only .rule-what, .rule[aria-pressed="true"] .rule-what { color: var(--dim); }
.rule.hit { border-color: rgba(255, 180, 84, 0.45); background: rgba(255, 180, 84, 0.06); }
.rule.hit.lvl-error { border-color: rgba(239, 106, 95, 0.5); background: rgba(239, 106, 95, 0.07); }
.rule-hits {
  position: absolute;
  top: 9px;
  right: 10px;
  min-width: 20px;
  padding: 0 6px;
  border-radius: 999px;
  background: var(--border-strong);
  color: var(--text);
  font: 600 11px/18px var(--mono);
  text-align: center;
}
.rule[aria-pressed="true"] .rule-id { text-decoration: line-through; }

@media (max-width: 900px) {
  .layout { grid-template-columns: minmax(0, 1fr); }
  .editor, .term { height: 440px; }
}

@media (max-width: 640px) {
  .seg button, select { min-height: 44px; }
}

/* Break it (PR 22): one-click mutations, a line diff, and findings pinned to editor lines. */
.break { margin: 0 0 18px; }
.break-row { display: flex; flex-wrap: wrap; gap: 8px; }
.break-row button { min-height: 44px; padding: 6px 12px; font: inherit; font-size: var(--fs-sm); color: var(--text); background: var(--bg); border: 1px solid var(--border); border-radius: 6px; cursor: pointer; }
.break-row button:hover { border-color: var(--amber); }
.break-row button:disabled { cursor: not-allowed; color: var(--dim); border-color: var(--border); }
.break-row .undo { border-color: var(--amber); color: var(--amber); }
.break-row .undo:disabled { border-color: var(--border); color: var(--dim); }
.break-summary { margin: 10px 0 0; min-height: 1.5em; font-family: var(--mono); font-size: var(--fs-sm); }
.break-summary .fail { color: var(--red); }
.break-summary .pass { color: var(--good); }
.diff { margin-top: 10px; }
.diff-title { margin: 0 0 4px; color: var(--muted); font-size: var(--fs-sm); }
.diff-body { margin: 0; padding: 8px 10px; overflow-x: auto; max-height: 14em; background: var(--term); border: 1px solid var(--border); border-radius: 6px; font: 12px/1.5 var(--mono); }
.diff-body .del { display: block; color: var(--red); }
.diff-body .add { display: block; color: var(--good); }
.diff-body .ctx { display: block; color: var(--dim); }
.gutter .mark-error { color: var(--red); }
.gutter .mark-warn { color: var(--amber); }
.gutter .mark-info { color: var(--teal); }
.annotations { list-style: none; margin: 6px 0 0; padding: 0; font: var(--fs-sm)/1.5 var(--mono); }
.annotations li { margin: 2px 0; color: var(--soft); }
.annotations .lvl-error { color: var(--red); }
.annotations .lvl-warn { color: var(--amber); }
.annotations .lvl-info { color: var(--teal); }