/* ============================================================
   Copilot → Agents course site
   Signature: the "autonomy spectrum" gradient (indigo→amber)
   Type: Space Grotesk (display) · IBM Plex Sans (body) · JetBrains Mono (code)
   ============================================================ */


/* ---- self-hosted fonts (SIL Open Font License) — no third-party CDN, removes the Google Fonts CDN/GDPR dependency ---- */
@font-face {
  font-family: 'IBM Plex Sans';
  font-style: normal;
  font-weight: 400;
  font-stretch: 100%;
  font-display: swap;
  src: url(fonts/ibm-plex-sans-400-latin-ext.woff2) format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
@font-face {
  font-family: 'IBM Plex Sans';
  font-style: normal;
  font-weight: 400;
  font-stretch: 100%;
  font-display: swap;
  src: url(fonts/ibm-plex-sans-400-latin.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 Sans';
  font-style: normal;
  font-weight: 500;
  font-stretch: 100%;
  font-display: swap;
  src: url(fonts/ibm-plex-sans-500-latin-ext.woff2) format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
@font-face {
  font-family: 'IBM Plex Sans';
  font-style: normal;
  font-weight: 500;
  font-stretch: 100%;
  font-display: swap;
  src: url(fonts/ibm-plex-sans-500-latin.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 Sans';
  font-style: normal;
  font-weight: 600;
  font-stretch: 100%;
  font-display: swap;
  src: url(fonts/ibm-plex-sans-600-latin-ext.woff2) format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
@font-face {
  font-family: 'IBM Plex Sans';
  font-style: normal;
  font-weight: 600;
  font-stretch: 100%;
  font-display: swap;
  src: url(fonts/ibm-plex-sans-600-latin.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: 'JetBrains Mono';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url(fonts/jetbrains-mono-400-latin-ext.woff2) format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
@font-face {
  font-family: 'JetBrains Mono';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url(fonts/jetbrains-mono-400-latin.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: 'JetBrains Mono';
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url(fonts/jetbrains-mono-500-latin-ext.woff2) format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
@font-face {
  font-family: 'JetBrains Mono';
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url(fonts/jetbrains-mono-500-latin.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: 'Space Grotesk';
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url(fonts/space-grotesk-500-latin-ext.woff2) format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
@font-face {
  font-family: 'Space Grotesk';
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url(fonts/space-grotesk-500-latin.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: 'Space Grotesk';
  font-style: normal;
  font-weight: 600;
  font-display: swap;
  src: url(fonts/space-grotesk-600-latin-ext.woff2) format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
@font-face {
  font-family: 'Space Grotesk';
  font-style: normal;
  font-weight: 600;
  font-display: swap;
  src: url(fonts/space-grotesk-600-latin.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: 'Space Grotesk';
  font-style: normal;
  font-weight: 700;
  font-display: swap;
  src: url(fonts/space-grotesk-700-latin-ext.woff2) format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
@font-face {
  font-family: 'Space Grotesk';
  font-style: normal;
  font-weight: 700;
  font-display: swap;
  src: url(fonts/space-grotesk-700-latin.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;
}

:root {
  /* surfaces */
  --bg:           #F4F6F9;
  --surface:      #FFFFFF;
  --surface-2:    #FAFBFD;
  --border:       #E4E8EF;
  --border-strong:#CBD3DF;

  /* ink */
  --ink:          #141E2C;
  --ink-soft:     #46546A;
  --ink-faint:    #66748A;

  /* spectrum anchors (low → high autonomy) */
  --indigo:       #4F46E5;
  --indigo-deep:  #4338CA;
  --violet:       #7C3AED;
  --pink:         #DB2777;
  --amber:        #E8890C;
  --amber-deep:   #C2710A;
  --spectrum: linear-gradient(90deg, #4F46E5 0%, #7C3AED 38%, #DB2777 68%, #E8890C 100%);

  /* code */
  --code-bg:      #0D1320;
  --code-bg-2:    #161E2E;
  --code-ink:     #E7EDF6;
  --code-faint:   #8595AD;
  --code-amber:   #F2B45A;
  --code-green:   #79D9A8;
  --code-blue:    #79B8FF;
  --code-pink:    #F490C0;

  /* callouts */
  --try-bg:   #FDF6EC;  --try-line:   #E8890C;  --try-ink:   #8A5208;
  --check-bg: #EEF0FE;  --check-line: #4F46E5;  --check-ink: #312B9C;
  --note-bg:  #F1F4F8;  --note-line:  #8A97A9;  --note-ink:  #46546A;
  --warn-bg:  #FCEEEE;  --warn-line:  #D03434;  --warn-ink:  #9A2222;
  --idea-bg:  #E9F6F4;  --idea-line:  #0E8C7E;  --idea-ink:  #0A5E54;

  --sidebar-w: 300px;
  --measure: 760px;
  --radius: 12px;
  --radius-sm: 8px;

  --font-display: "Space Grotesk", ui-sans-serif, system-ui, sans-serif;
  --font-body: "IBM Plex Sans", ui-sans-serif, system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, monospace;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* ---------- layout shell ---------- */
.layout { display: flex; min-height: 100vh; }

.sidebar {
  width: var(--sidebar-w);
  flex: 0 0 var(--sidebar-w);
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
  background: var(--surface);
  border-right: 1px solid var(--border);
  padding: 0 0 2rem;
}
.sidebar::-webkit-scrollbar { width: 8px; }
.sidebar::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 8px; }

.brand {
  position: sticky; top: 0;
  background: var(--surface);
  padding: 1.5rem 1.5rem 1.1rem;
  border-bottom: 1px solid var(--border);
  z-index: 2;
}
.brand a { text-decoration: none; color: inherit; display: block; }
.brand .spectrum-bar {
  height: 5px; border-radius: 99px; background: var(--spectrum);
  margin-bottom: 0.85rem;
}
.brand .title {
  font-family: var(--font-display);
  font-weight: 700; font-size: 1.08rem; letter-spacing: -0.01em;
  line-height: 1.25; color: var(--ink);
}
.brand .subtitle {
  font-size: 0.74rem; color: var(--ink-faint); margin-top: 0.25rem;
  letter-spacing: 0.02em;
}

.nav { padding: 1rem 0.85rem 0; }
.nav .group-label {
  font-family: var(--font-display);
  font-size: 0.68rem; font-weight: 600; letter-spacing: 0.13em;
  text-transform: uppercase; color: var(--ink-faint);
  padding: 1.1rem 0.65rem 0.45rem;
}
.nav a {
  display: flex; align-items: baseline; gap: 0.6rem;
  text-decoration: none;
  color: var(--ink-soft);
  font-size: 0.92rem;
  padding: 0.42rem 0.65rem;
  border-radius: var(--radius-sm);
  transition: background 0.15s, color 0.15s;
}
.nav a .num {
  font-family: var(--font-mono);
  font-size: 0.72rem; color: var(--ink-faint);
  flex: 0 0 1.6rem;
}
.nav a:hover { background: var(--surface-2); color: var(--ink); }
.nav a.active {
  background: linear-gradient(90deg, rgba(79,70,229,0.10), rgba(79,70,229,0.02));
  color: var(--indigo-deep);
  font-weight: 600;
  box-shadow: inset 3px 0 0 var(--indigo);
}
.nav a.active .num { color: var(--indigo); }

/* ---------- topbar (mobile) ---------- */
.topbar {
  display: none;
  position: sticky; top: 0; z-index: 40;
  align-items: center; gap: 0.8rem;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 0.7rem 1rem;
}
.topbar .spectrum-bar { height: 4px; flex: 1; border-radius: 99px; background: var(--spectrum); }
.menu-btn {
  border: 1px solid var(--border-strong); background: var(--surface);
  border-radius: var(--radius-sm); width: 40px; height: 40px;
  font-size: 1.2rem; cursor: pointer; color: var(--ink);
  display: inline-flex; align-items: center; justify-content: center;
}
.scrim {
  display: none; position: fixed; inset: 0; background: rgba(8,12,20,0.45);
  z-index: 30;
}

/* ---------- content ---------- */
.content {
  flex: 1 1 auto;
  min-width: 0;
  padding: 3.2rem 2.6rem 5rem;
  display: flex; justify-content: center;
}
.content > .inner { width: 100%; max-width: var(--measure); }

/* page header */
.eyebrow {
  font-family: var(--font-display);
  font-size: 0.74rem; font-weight: 600; letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--indigo);
  display: inline-flex; align-items: center; gap: 0.6rem;
}
.eyebrow .dot { width: 6px; height: 6px; border-radius: 99px; background: var(--amber); }

h1 {
  font-family: var(--font-display);
  font-weight: 700; font-size: clamp(2rem, 4.4vw, 2.7rem);
  letter-spacing: -0.025em; line-height: 1.08;
  margin: 0.85rem 0 0.5rem;
}
.lead {
  font-size: 1.18rem; line-height: 1.55; color: var(--ink-soft);
  margin: 0 0 1.4rem;
}

h2 {
  font-family: var(--font-display);
  font-weight: 600; font-size: 1.55rem; letter-spacing: -0.02em;
  line-height: 1.2;
  margin: 3rem 0 0.9rem; padding-top: 1.4rem;
  border-top: 1px solid var(--border);
}
h2:first-of-type { border-top: none; padding-top: 0; }
h3 {
  font-family: var(--font-body);
  font-weight: 600; font-size: 1.18rem; color: var(--ink);
  margin: 2rem 0 0.6rem;
}
h4 {
  font-family: var(--font-body);
  font-weight: 600; font-size: 1rem; color: var(--ink);
  margin: 1.4rem 0 0.4rem;
}

p { margin: 0 0 1.05rem; }
.content a {
  color: var(--indigo-deep);
  text-decoration: underline;
  text-decoration-color: rgba(79,70,229,0.3);
  text-underline-offset: 2px;
}
.content a:hover { text-decoration-color: var(--indigo); }

strong { font-weight: 600; color: var(--ink); }
em { font-style: italic; }

ul, ol { margin: 0 0 1.2rem; padding-left: 1.4rem; }
li { margin: 0 0 0.5rem; padding-left: 0.2rem; }
li::marker { color: var(--ink-faint); }
ol li::marker { color: var(--indigo); font-weight: 600; font-family: var(--font-mono); font-size: 0.9em; }

hr {
  border: none; border-top: 1px solid var(--border);
  margin: 2.5rem 0;
}

/* inline code */
code {
  font-family: var(--font-mono);
  font-size: 0.86em;
  background: #EAEEF4;
  color: #2A3A52;
  padding: 0.12em 0.4em;
  border-radius: 5px;
  border: 1px solid #DDE3EC;
}

/* code blocks */
.code {
  position: relative;
  background: var(--code-bg);
  border-radius: var(--radius);
  margin: 0 0 1.4rem;
  overflow: hidden;
  border: 1px solid #1E2940;
}
.code .code-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 0.5rem 0.9rem;
  background: var(--code-bg-2);
  border-bottom: 1px solid #1E2940;
}
.code .lang {
  font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--code-faint);
}
.code .copy {
  border: 1px solid #2A3650; background: transparent; color: var(--code-faint);
  font-family: var(--font-mono); font-size: 0.68rem; cursor: pointer;
  padding: 0.2rem 0.55rem; border-radius: 6px; transition: 0.15s;
}
.code .copy:hover { color: var(--code-ink); border-color: #3A4870; }
.code pre {
  margin: 0; padding: 1rem 1.1rem; overflow-x: auto;
  font-family: var(--font-mono); font-size: 0.82rem; line-height: 1.6;
  color: var(--code-ink);
}
.code pre::-webkit-scrollbar { height: 8px; }
.code pre::-webkit-scrollbar-thumb { background: #2A3650; border-radius: 8px; }

/* schematic / ASCII diagram block */
.schematic {
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 3px solid var(--violet);
  border-radius: var(--radius);
  margin: 0 0 1.4rem;
  overflow: hidden;
}
.schematic .cap {
  font-family: var(--font-display); font-size: 0.68rem; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--ink-faint);
  padding: 0.55rem 0.9rem; border-bottom: 1px solid var(--border);
  background: var(--surface-2);
}
.schematic pre {
  margin: 0; padding: 1.1rem; overflow-x: auto;
  font-family: var(--font-mono); font-size: 0.76rem; line-height: 1.45;
  color: var(--ink-soft);
}
.schematic pre::-webkit-scrollbar { height: 8px; }
.schematic pre::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 8px; }

/* callouts */
.callout {
  border-radius: var(--radius);
  padding: 1rem 1.2rem 1rem 1.25rem;
  margin: 0 0 1.4rem;
  border-left: 4px solid var(--note-line);
  background: var(--note-bg);
}
.callout .tag {
  display: inline-flex; align-items: center; gap: 0.45rem;
  font-family: var(--font-display); font-weight: 600;
  font-size: 0.72rem; letter-spacing: 0.1em; text-transform: uppercase;
  margin-bottom: 0.5rem;
  color: var(--note-ink);
}
.callout p:last-child, .callout ul:last-child, .callout ol:last-child { margin-bottom: 0; }
.callout.try   { background: var(--try-bg);   border-color: var(--try-line); }
.callout.try .tag   { color: var(--try-ink); }
.callout.check { background: var(--check-bg); border-color: var(--check-line); }
.callout.check .tag { color: var(--check-ink); }
.callout.warn  { background: var(--warn-bg);  border-color: var(--warn-line); }
.callout.warn .tag  { color: var(--warn-ink); }
.callout.idea  { background: var(--idea-bg);  border-color: var(--idea-line); }
.callout.idea .tag  { color: var(--idea-ink); }

/* tables */
.table-wrap { overflow-x: auto; margin: 0 0 1.4rem; border-radius: var(--radius); border: 1px solid var(--border); }
table { width: 100%; border-collapse: collapse; font-size: 0.92rem; background: var(--surface); }
th, td { text-align: left; padding: 0.7rem 0.9rem; border-bottom: 1px solid var(--border); vertical-align: top; }
th {
  font-family: var(--font-display); font-weight: 600; font-size: 0.78rem;
  letter-spacing: 0.04em; text-transform: uppercase; color: var(--ink-soft);
  background: var(--surface-2);
}
tr:last-child td { border-bottom: none; }
td code { font-size: 0.82em; }

/* ---------- home page ---------- */
.hero {
  border-radius: 18px;
  background:
    radial-gradient(120% 140% at 0% 0%, rgba(79,70,229,0.10), transparent 55%),
    radial-gradient(120% 140% at 100% 100%, rgba(232,137,12,0.12), transparent 55%),
    var(--surface);
  border: 1px solid var(--border);
  padding: 2.6rem 2.4rem;
  margin-bottom: 2.4rem;
}
.hero h1 { font-size: clamp(2.2rem, 5vw, 3.1rem); margin-top: 0.7rem; }

/* the signature: autonomy spectrum */
.spectrum {
  margin: 2rem 0 0.5rem;
}
.spectrum .rail {
  height: 10px; border-radius: 99px; background: var(--spectrum);
  position: relative; margin-bottom: 1.1rem;
}
.spectrum .ticks {
  display: grid; grid-template-columns: repeat(6, 1fr); gap: 0.5rem;
}
.spectrum .tick { text-align: center; }
.spectrum .tick .k {
  font-family: var(--font-display); font-weight: 600; font-size: 0.82rem;
  color: var(--ink); display: block; line-height: 1.2;
}
.spectrum .tick .v { font-size: 0.72rem; color: var(--ink-faint); }
.spectrum .ends {
  display: flex; justify-content: space-between;
  font-family: var(--font-mono); font-size: 0.7rem; color: var(--ink-faint);
  margin-top: 0.4rem;
}

/* per-page spectrum locator */
.locator {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 0.9rem 1.1rem; margin: 0 0 1.8rem;
}
.locator .lab {
  font-family: var(--font-display); font-size: 0.68rem; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--ink-faint); margin-bottom: 0.6rem;
}
.locator .rail { height: 8px; border-radius: 99px; background: var(--spectrum); position: relative; }
.locator .pin {
  position: absolute; top: 50%; width: 16px; height: 16px; border-radius: 99px;
  background: #fff; border: 3px solid var(--ink); transform: translate(-50%, -50%);
  box-shadow: 0 1px 4px rgba(0,0,0,0.2);
}
.locator .where { font-size: 0.84rem; color: var(--ink-soft); margin-top: 0.6rem; }

/* topic grid */
.grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(248px, 1fr));
  gap: 1rem; margin: 1.4rem 0;
}
.card {
  text-decoration: none; color: inherit;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 1.2rem 1.3rem;
  transition: border-color 0.15s, transform 0.15s, box-shadow 0.15s;
  display: flex; flex-direction: column; gap: 0.35rem;
}
.card:hover {
  border-color: var(--indigo); transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(79,70,229,0.10);
}
.card .num {
  font-family: var(--font-mono); font-size: 0.72rem; color: var(--ink-faint);
}
.card h3 { margin: 0; font-family: var(--font-display); font-size: 1.05rem; }
.card p { margin: 0; font-size: 0.88rem; color: var(--ink-soft); line-height: 1.5; }

/* objectives box */
.objectives {
  background: var(--surface-2); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 1.1rem 1.3rem; margin: 0 0 1.8rem;
}
.objectives .lab {
  font-family: var(--font-display); font-size: 0.7rem; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--indigo); margin-bottom: 0.5rem; font-weight: 600;
}
.objectives p { margin: 0; color: var(--ink-soft); font-size: 0.96rem; }

/* key takeaway pill */
.keyline {
  border-left: 4px solid var(--amber);
  background: linear-gradient(90deg, rgba(232,137,12,0.07), transparent);
  padding: 0.9rem 1.2rem; border-radius: 0 var(--radius) var(--radius) 0;
  margin: 0 0 1.4rem; font-size: 1.02rem;
}
.keyline strong { color: var(--amber-deep); }

/* ---------- pagination ---------- */
.pager {
  display: flex; gap: 1rem; margin-top: 3.5rem;
  border-top: 1px solid var(--border); padding-top: 1.6rem;
}
.pager a {
  flex: 1; text-decoration: none; color: inherit;
  border: 1px solid var(--border); border-radius: var(--radius);
  padding: 0.9rem 1.1rem; transition: border-color 0.15s, background 0.15s;
}
.pager a:hover { border-color: var(--indigo); background: var(--surface); }
.pager .dir { font-family: var(--font-mono); font-size: 0.7rem; color: var(--ink-faint); }
.pager .t { font-family: var(--font-display); font-weight: 600; color: var(--ink); display: block; margin-top: 0.2rem; }
.pager .next { text-align: right; }

/* footer */
.foot {
  margin-top: 2.4rem; padding-top: 1.4rem; border-top: 1px solid var(--border);
  font-size: 0.82rem; color: var(--ink-faint);
}
.foot .spectrum-bar { height: 4px; border-radius: 99px; background: var(--spectrum); margin-bottom: 1rem; max-width: 160px; }

/* focus visibility */
a:focus-visible, button:focus-visible {
  outline: 3px solid rgba(79,70,229,0.5); outline-offset: 2px; border-radius: 4px;
}

/* ---------- responsive ---------- */
@media (max-width: 940px) {
  .sidebar {
    position: fixed; left: 0; top: 0; z-index: 35;
    transform: translateX(-100%); transition: transform 0.22s ease;
    box-shadow: 4px 0 28px rgba(8,12,20,0.18);
  }
  body.nav-open .sidebar { transform: translateX(0); }
  body.nav-open .scrim { display: block; }
  .topbar { display: flex; }
  .content { padding: 1.8rem 1.3rem 4rem; }
  .hero { padding: 1.8rem 1.4rem; }
  .spectrum .ticks { grid-template-columns: repeat(3, 1fr); row-gap: 0.8rem; }
}
@media (prefers-reduced-motion: reduce) {
  .sidebar { transition: none; }
  .card:hover { transform: none; }
}

/* ---------- self-check quiz ---------- */
.quiz-meta {
  position: sticky; top: 0; z-index: 5;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 0.7rem 1rem; margin: 0 0 1.4rem;
  display: flex; align-items: center; justify-content: space-between; gap: 1rem;
  flex-wrap: wrap;
}
.quiz-meta .stat { font-family: var(--font-display); font-weight: 600; font-size: 0.92rem; }
.quiz-meta .stat .n { color: var(--indigo-deep); }
.quiz-meta .stat .c { color: var(--idea-line); }
.quiz-meta .bar { flex: 1 1 160px; height: 8px; border-radius: 99px; background: var(--border); overflow: hidden; min-width: 120px; }
.quiz-meta .bar > span { display: block; height: 100%; width: 0; background: var(--spectrum); transition: width 0.3s; }
.quiz-meta button {
  border: 1px solid var(--border-strong); background: var(--surface); color: var(--ink-soft);
  font-family: var(--font-mono); font-size: 0.72rem; cursor: pointer;
  padding: 0.35rem 0.7rem; border-radius: 6px;
}
.quiz-meta button:hover { border-color: var(--indigo); color: var(--indigo-deep); }
.q {
  border: 1px solid var(--border); border-radius: var(--radius);
  background: var(--surface); padding: 1.1rem 1.2rem; margin: 0 0 1.1rem;
}
.q .chip {
  display: inline-block; font-family: var(--font-display); font-size: 0.64rem;
  letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-faint);
  border: 1px solid var(--border); border-radius: 99px; padding: 0.1rem 0.55rem; margin-bottom: 0.55rem;
}
.q .stem { font-weight: 600; margin: 0 0 0.8rem; }
.q .stem .qnum { color: var(--ink-faint); font-family: var(--font-mono); font-size: 0.85em; margin-right: 0.4rem; }
.q .opt {
  display: block; width: 100%; text-align: left; cursor: pointer;
  border: 1px solid var(--border); background: var(--surface-2);
  border-radius: var(--radius-sm); padding: 0.6rem 0.85rem; margin: 0 0 0.5rem;
  font-family: var(--font-body); font-size: 0.95rem; color: var(--ink);
  transition: border-color 0.12s, background 0.12s;
}
.q .opt:hover:not(:disabled) { border-color: var(--indigo); }
.q .opt:disabled { cursor: default; }
.q .opt .mk { font-family: var(--font-mono); color: var(--ink-faint); margin-right: 0.5rem; }
.q .opt.correct { background: var(--idea-bg); border-color: var(--idea-line); color: var(--idea-ink); font-weight: 600; }
.q .opt.wrong { background: var(--warn-bg); border-color: var(--warn-line); color: var(--warn-ink); }
.q .opt .ostat { margin-left: 0.5rem; font-weight: 700; font-family: var(--font-mono); font-size: 0.8em; }
.q .exp {
  display: none; margin-top: 0.6rem; padding: 0.7rem 0.9rem;
  background: var(--check-bg); border-left: 4px solid var(--check-line); border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: 0.9rem; color: var(--check-ink);
}
.q.answered .exp { display: block; }
.q .exp b { color: var(--check-ink); }
.quiz-done {
  display: none; border-radius: var(--radius); padding: 1.2rem 1.3rem; margin: 0 0 1.2rem;
  background: linear-gradient(90deg, rgba(79,70,229,0.08), rgba(232,137,12,0.08));
  border: 1px solid var(--border); font-family: var(--font-display); font-weight: 600;
}
.quiz-done.show { display: block; }

/* ---------- flashcards ---------- */
.fc-bar { display: flex; align-items: center; gap: 1rem; flex-wrap: wrap; margin: 0 0 1.2rem;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 0.7rem 1rem; }
.fc-bar .stat { font-family: var(--font-display); font-weight: 600; font-size: 0.92rem; }
.fc-bar .stat .k { color: var(--idea-line); } .fc-bar .stat .r { color: var(--indigo-deep); }
.fc-bar .prog { flex: 1 1 140px; height: 8px; min-width: 110px; border-radius: 99px; background: var(--border); overflow: hidden; }
.fc-bar .prog > span { display: block; height: 100%; width: 0; background: var(--spectrum); transition: width 0.3s; }
.fc-scene { perspective: 1200px; margin: 0 0 1rem; }
.fc-card { position: relative; width: 100%; min-height: 230px; cursor: pointer;
  transform-style: preserve-3d; transition: transform 0.5s; }
.fc-card.is-flipped { transform: rotateY(180deg); }
.fc-face { position: absolute; inset: 0; backface-visibility: hidden; -webkit-backface-visibility: hidden;
  display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center;
  border-radius: 14px; border: 1px solid var(--border); padding: 1.6rem 1.8rem; }
.fc-front { background: radial-gradient(120% 140% at 0% 0%, rgba(79,70,229,0.10), transparent 60%), var(--surface); }
.fc-back { background: radial-gradient(120% 140% at 100% 100%, rgba(232,137,12,0.12), transparent 60%), var(--surface); transform: rotateY(180deg); }
.fc-face .lab { font-family: var(--font-display); font-size: 0.64rem; letter-spacing: 0.16em; text-transform: uppercase; color: var(--ink-faint); margin-bottom: 0.7rem; }
.fc-front .term { font-family: var(--font-display); font-weight: 700; font-size: 1.5rem; letter-spacing: -0.01em; color: var(--ink); }
.fc-back .def { font-size: 1.02rem; line-height: 1.55; color: var(--ink); max-width: 46ch; }
.fc-face .chip { margin-top: 0.9rem; font-size: 0.64rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-faint); border: 1px solid var(--border); border-radius: 99px; padding: 0.1rem 0.55rem; }
.fc-face .hint { position: absolute; bottom: 0.7rem; right: 0.9rem; font-family: var(--font-mono); font-size: 0.66rem; color: var(--ink-faint); }
.fc-controls { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.fc-controls button { font-family: var(--font-display); font-weight: 600; font-size: 0.84rem; cursor: pointer;
  border: 1px solid var(--border-strong); background: var(--surface); color: var(--ink); border-radius: 8px; padding: 0.5rem 0.9rem; transition: 0.12s; }
.fc-controls button:hover { border-color: var(--indigo); color: var(--indigo-deep); }
.fc-controls .primary { background: var(--indigo); border-color: var(--indigo); color: #fff; }
.fc-controls .primary:hover { background: var(--indigo-deep); color: #fff; }
.fc-controls .known { background: var(--idea-bg); border-color: var(--idea-line); color: var(--idea-ink); }
.fc-empty { display: none; text-align: center; padding: 2rem; border: 1px dashed var(--border-strong); border-radius: var(--radius); color: var(--ink-soft); }

/* ---------- lab checklist ---------- */
.lab-bar { position: sticky; top: 0; z-index: 5; display: flex; align-items: center; gap: 1rem; flex-wrap: wrap;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 0.7rem 1rem; margin: 0 0 1.4rem; }
.lab-bar .stat { font-family: var(--font-display); font-weight: 600; font-size: 0.92rem; }
.lab-bar .stat .d { color: var(--idea-line); }
.lab-bar .prog { flex: 1 1 140px; height: 8px; min-width: 110px; border-radius: 99px; background: var(--border); overflow: hidden; }
.lab-bar .prog > span { display: block; height: 100%; width: 0; background: var(--spectrum); transition: width 0.3s; }
.lab-bar button { border: 1px solid var(--border-strong); background: var(--surface); color: var(--ink-soft); font-family: var(--font-mono); font-size: 0.72rem; cursor: pointer; padding: 0.35rem 0.7rem; border-radius: 6px; }
.lab { display: flex; gap: 0.9rem; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); padding: 1rem 1.1rem; margin: 0 0 0.9rem; transition: border-color 0.15s, background 0.15s; }
.lab.done { background: var(--idea-bg); border-color: var(--idea-line); }
.lab .box { flex: 0 0 auto; padding-top: 0.15rem; }
.lab .box input { width: 20px; height: 20px; cursor: pointer; accent-color: var(--idea-line); }
.lab .body { flex: 1; min-width: 0; }
.lab .ttl { font-family: var(--font-display); font-weight: 600; font-size: 1.05rem; }
.lab .ttl .n { font-family: var(--font-mono); color: var(--indigo); font-size: 0.85em; margin-right: 0.45rem; }
.lab.done .ttl { text-decoration: line-through; text-decoration-color: var(--idea-line); }
.lab .do { margin: 0.3rem 0 0.4rem; font-size: 0.95rem; }
.lab .ok { font-size: 0.86rem; color: var(--ink-soft); }
.lab .ok b { color: var(--idea-ink); }
.lab .lk { font-size: 0.82rem; margin-top: 0.3rem; }

/* ---------- domain filter bar (quiz + flashcards) ---------- */
.filter-bar { display: flex; flex-wrap: wrap; gap: 0.4rem; margin: 0 0 1.1rem; align-items: center; }
.filter-bar .flab { font-family: var(--font-display); font-size: 0.7rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--ink-faint); margin-right: 0.3rem; }
.filter-bar button { font-family: var(--font-mono); font-size: 0.74rem; cursor: pointer; border: 1px solid var(--border); background: var(--surface); color: var(--ink-soft); border-radius: 99px; padding: 0.28rem 0.7rem; transition: 0.12s; }
.filter-bar button:hover { border-color: var(--indigo); color: var(--indigo-deep); }
.filter-bar button.on { background: var(--indigo); border-color: var(--indigo); color: #fff; }
.filter-bar button.gh { border-color: var(--amber); color: var(--amber-ink, #8A5208); }
.filter-bar button.gh.on { background: var(--amber); border-color: var(--amber); color: #fff; }

/* ---------- tabbed hubs ---------- */
.tabs { display: flex; gap: 0.2rem; flex-wrap: wrap; border-bottom: 2px solid var(--border); margin: 0 0 1.5rem; }
.tab { font-family: var(--font-display); font-weight: 600; font-size: 0.92rem; cursor: pointer; border: none; background: none; color: var(--ink-soft); padding: 0.6rem 0.9rem; border-bottom: 2px solid transparent; margin-bottom: -2px; transition: 0.12s; }
.tab:hover { color: var(--indigo-deep); }
.tab.on { color: var(--indigo-deep); border-bottom-color: var(--indigo); }
.tabpanel { display: none; }
.tabpanel.on { display: block; animation: fadein 0.2s ease; }
@keyframes fadein { from { opacity: 0; } to { opacity: 1; } }

/* ---------- certification track cards (home) ---------- */
.tracks { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; margin: 1.5rem 0; }
@media (max-width: 680px) { .tracks { grid-template-columns: 1fr; } }
.track { display: block; text-decoration: none; color: inherit; border: 1px solid var(--border); border-radius: var(--radius); padding: 1.3rem 1.4rem 1.3rem 1.6rem; background: var(--surface); transition: 0.15s; position: relative; overflow: hidden; }
.track:hover { border-color: var(--indigo); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(79,70,229,0.10); }
.track::before { content: ""; position: absolute; left: 0; top: 0; bottom: 0; width: 4px; background: var(--spectrum); }
.track .badge { font-family: var(--font-mono); font-size: 0.72rem; color: var(--indigo-deep); background: var(--surface-2); border: 1px solid var(--border); border-radius: 99px; padding: 0.15rem 0.6rem; display: inline-block; margin-bottom: 0.6rem; }
.track h3 { font-family: var(--font-display); font-size: 1.18rem; margin: 0 0 0.35rem; }
.track p { margin: 0 0 0.55rem; color: var(--ink-soft); font-size: 0.95rem; }
.track .go { font-family: var(--font-display); font-weight: 600; font-size: 0.85rem; color: var(--indigo-deep); }

/* ---------- provider lenses (home) ---------- */
.lenses { display: grid; grid-template-columns: repeat(3, 1fr); gap: 0.8rem; margin: 1.2rem 0; }
@media (max-width: 680px) { .lenses { grid-template-columns: 1fr; } }
.lens { border: 1px solid var(--border); border-radius: var(--radius); padding: 1rem 1.1rem; background: var(--surface-2); }
.lens h4 { font-family: var(--font-display); font-size: 1.02rem; margin: 0 0 0.2rem; }
.lens .tag2 { font-family: var(--font-mono); font-size: 0.68rem; color: var(--ink-faint); text-transform: uppercase; letter-spacing: 0.06em; }
.lens p { margin: 0.35rem 0 0; font-size: 0.88rem; color: var(--ink-soft); }

/* ---------- launch button (cert apps) ---------- */
/* raised to a.launch so it beats ".content a" (which would force dark text + underline) */
a.launch { display: inline-flex; align-items: center; gap: 0.5rem; font-family: var(--font-display); font-weight: 600; font-size: 0.98rem; text-decoration: none; color: #fff; background: var(--indigo); border: 1px solid var(--indigo); border-radius: 10px; padding: 0.7rem 1.2rem; transition: 0.15s; }
a.launch:hover { background: var(--indigo-deep); border-color: var(--indigo-deep); color: #fff; text-decoration: none; }
/* secondary / outlined companion button — pairs cleanly with the filled primary */
a.launch.alt { background: var(--surface); color: var(--indigo-deep); border-color: var(--border-strong); }
a.launch.alt:hover { background: var(--surface-2); border-color: var(--indigo); color: var(--indigo-deep); text-decoration: none; }
/* legacy blue variant (kept for compatibility) */
a.launch.gh { background: #1F6FEB; border-color: #1F6FEB; color: #fff; }
a.launch.gh:hover { background: #1A5FCC; border-color: #1A5FCC; color: #fff; text-decoration: none; }

.filter-bar button.cc { border-color: #7C3AED; color: #6D28D9; }
.filter-bar button.cc:hover { border-color: #6D28D9; color: #5B21B6; }
.filter-bar button.cc.on { background: #7C3AED; border-color: #7C3AED; color: #fff; }
.filter-bar button.oa { border-color: #0E8C7E; color: #0B7568; }
.filter-bar button.oa:hover { border-color: #0B7568; color: #084a41; }
.filter-bar button.oa.on { background: #0E8C7E; border-color: #0E8C7E; color: #fff; }
.filter-bar button.gg { border-color: #1A73E8; color: #1558b0; }
.filter-bar button.gg:hover { border-color: #1558b0; color: #0f3f80; }
.filter-bar button.gg.on { background: #1A73E8; border-color: #1A73E8; color: #fff; }

.schematic svg { display: block; width: 100%; height: auto; max-width: 760px; margin: 0 auto; padding: 1.1rem 1rem; }

.callout.eli { background: #F0FBF4; border-color: #BFE9CC; }
.callout.eli .tag { color: #128A4E; }

/* compact per-section "explain like I'm 10" note — sits right under an h2/h3 */
.eli-note {
  margin: -0.2rem 0 1.15rem;
  padding: 0.55rem 0.9rem 0.6rem;
  border-left: 3px solid #7FCF9C;
  background: #F0FBF4;
  border-radius: 0 8px 8px 0;
  font-size: 0.92rem;
  line-height: 1.5;
  color: var(--ink-soft);
}
.eli-note b {
  color: #128A4E;
  font-family: var(--font-display);
  font-weight: 600;
  letter-spacing: 0.01em;
}
.eli-note code { background: rgba(18,138,78,0.08); }

/* ============================================================
   AI Academy — recurring animal-character cast
   ============================================================ */
/* per-page host banner: who teaches this topic */
.cast-strip {
  display: flex; align-items: center; gap: 0.75rem;
  margin: 0 0 1.5rem; padding: 0.6rem 0.95rem;
  border: 1px solid var(--border); border-left: 4px solid var(--violet);
  border-radius: 0 10px 10px 0;
  background: linear-gradient(180deg, #FBF7FF, #F8F4FD);
  font-size: 0.92rem; color: var(--ink-soft); line-height: 1.5;
}
.cast-strip .emos { font-size: 1.55rem; line-height: 1; white-space: nowrap; flex: none; }
.cast-strip b { color: var(--ink); font-family: var(--font-display); font-weight: 600; }

/* storyline dialogue — a little "scene" at the AI Academy */
.toon {
  margin: 1.3rem 0 1.6rem; padding: 0.9rem 1.15rem 1rem;
  border: 1px solid #E6D8F5; border-radius: 14px;
  background: linear-gradient(180deg, #FBF7FF, #F6F1FC);
}
.toon .toon-cap {
  display: flex; align-items: center; gap: 0.4rem;
  font-family: var(--font-display); font-weight: 600; font-size: 0.72rem;
  letter-spacing: 0.1em; text-transform: uppercase; color: var(--violet);
  margin-bottom: 0.65rem;
}
.toon .line { display: flex; gap: 0.65rem; margin: 0.4rem 0; align-items: baseline; }
.toon .line .em { font-size: 1.2rem; line-height: 1.4; flex: none; width: 1.7rem; text-align: center; }
.toon .line .sp { margin: 0; }
.toon .line .sp b { font-family: var(--font-display); font-weight: 600; color: var(--ink); }
.toon .line .sp .role { color: var(--ink-faint); font-size: 0.82rem; }

/* home "Meet the AI Academy" cast grid */
.cast-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 0.7rem; margin: 1.4rem 0; }
@media (max-width: 680px) { .cast-grid { grid-template-columns: 1fr; } }
.cast-card {
  display: flex; gap: 0.75rem; align-items: flex-start;
  border: 1px solid var(--border); border-radius: 12px;
  padding: 0.85rem 0.95rem; background: var(--surface-2);
}
.cast-card .ava { font-size: 1.85rem; line-height: 1; flex: none; }
.cast-card .role2 { font-family: var(--font-mono); font-size: 0.66rem; text-transform: uppercase; letter-spacing: 0.05em; color: var(--indigo-deep); }
.cast-card h4 { font-family: var(--font-display); font-size: 0.98rem; margin: 0.1rem 0 0.2rem; }
.cast-card p { margin: 0; font-size: 0.85rem; color: var(--ink-soft); line-height: 1.45; }

/* "pick your provider" dropdowns — a distinct accented CARD so they stand out while scrolling */
.picker {
  margin: 1.6rem 0;
  padding: 0.9rem 1.15rem 1.15rem;
  background: linear-gradient(180deg, #FBF7FF, #F6F2FC);
  border: 1px solid #E6D8F5; border-left: 4px solid var(--violet);
  border-radius: 0 12px 12px 0;
}
.prov-picker { display: flex; align-items: center; gap: 0.6rem; margin: 0 0 0.9rem; flex-wrap: wrap; }
.prov-picker label {
  font-family: var(--font-display); font-weight: 600;
  font-size: 0.72rem; letter-spacing: 0.09em; text-transform: uppercase; color: var(--violet);
  display: inline-flex; align-items: center; gap: 0.4rem;
}
.prov-picker label::before { content: "⇅"; font-size: 1rem; }
.prov-picker select {
  font: inherit; font-size: 1rem; font-weight: 600;
  padding: 0.5rem 0.85rem; border: 1.5px solid var(--violet); border-radius: 8px;
  background: var(--surface); color: var(--ink); cursor: pointer;
  box-shadow: 0 1px 3px rgba(124,58,237,0.15); transition: border-color .15s, box-shadow .15s;
}
.prov-picker select:hover, .prov-picker select:focus { border-color: var(--indigo-deep); box-shadow: 0 2px 8px rgba(124,58,237,0.22); outline: none; }
.prov-picker .hint { font-size: 0.85rem; color: var(--ink-faint); }
/* Progressive enhancement: panels are all visible by default; only collapse to the
   selected one once JS wires the picker (wirePickers adds .js-ready). So if JS is
   missing or a stale site.js is cached, EVERY labelled panel shows — never a wrong one. */
.picker.js-ready .prov-panel { display: none; }
.picker.js-ready .prov-panel.on { display: block; animation: fadein 0.2s ease; }
.prov-panel { margin-top: 0.4rem; }
.prov-panel .prov-head { font-family: var(--font-display); font-weight: 600; font-size: 0.95rem; margin: 0.2rem 0 0.5rem; color: var(--indigo-deep); }

/* ---- checkpoint answer-key reveal (collapsible; closes the feedback loop) ---- */
.answer-key { margin: 0.7rem 0 0; border: 1px solid var(--border); border-radius: 10px; background: var(--surface-2); padding: 0 0.95rem; }
.answer-key > summary { cursor: pointer; padding: 0.7rem 0; font-weight: 600; color: var(--indigo-deep); list-style: none; }
.answer-key > summary::-webkit-details-marker { display: none; }
.answer-key > summary::before { content: "▸ "; }
.answer-key[open] > summary::before { content: "▾ "; }
.answer-key ol { margin: 0 0 0.85rem; padding-left: 1.4rem; }
.answer-key li { margin: 0.4rem 0; color: var(--ink-soft); }
.answer-key li b, .answer-key li strong { color: var(--ink); }

/* ---- skip-to-content link (accessibility) ---- */
.skip-link {
  position: absolute; left: 8px; top: -48px; z-index: 1000;
  background: var(--indigo-deep); color: #fff;
  padding: 0.55rem 0.9rem; border-radius: 8px;
  font-weight: 600; font-size: 0.9rem; text-decoration: none;
  transition: top 0.15s ease;
}
.skip-link:focus { top: 8px; outline: 3px solid #fff; outline-offset: 2px; }

/* ---- print stylesheet: clean, chrome-free pages for PDF/paper ---- */
@media print {
  .sidebar, .topbar, .scrim, .pager, .skip-link, .copy, .menu-btn { display: none !important; }
  .layout { display: block !important; }
  .main-col, .content, .inner { display: block !important; width: auto !important; max-width: none !important; margin: 0 !important; padding: 0 !important; }
  body, .content { background: #fff !important; color: #000 !important; }
  a { color: #000 !important; text-decoration: underline; }
  pre, code { white-space: pre-wrap !important; word-wrap: break-word; }
  .code, .schematic, table, .callout, .toon, blockquote, li, tr, img, svg { break-inside: avoid; page-break-inside: avoid; }
  h1, h2, h3 { break-after: avoid; page-break-after: avoid; }
  .foot { border-top: 1px solid #999; color: #000 !important; }
  .foot .spectrum-bar, .brand .spectrum-bar { display: none !important; }
}

/* ===================================================================
   Learning Cloud Migration — hub additions (flip flashcards + filter)
   Uses the existing design tokens so it matches the shared system.
   =================================================================== */
.deck { display: grid; gap: 1rem; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); }
.deck-tools { display: flex; flex-wrap: wrap; gap: 0.6rem; align-items: center; margin: 0 0 0.9rem; }
.flip {
  perspective: 1400px; height: 200px; cursor: pointer; outline-offset: 3px;
}
.flip .fp {
  position: relative; width: 100%; height: 100%;
  transition: transform 0.5s cubic-bezier(0.4,0.15,0.2,1); transform-style: preserve-3d;
}
.flip.flipped .fp { transform: rotateY(180deg); }
.flip .face {
  position: absolute; inset: 0; backface-visibility: hidden;
  border: 1px solid var(--border); border-radius: var(--radius);
  padding: 1.1rem 1.25rem; display: flex; flex-direction: column; justify-content: center;
  background: var(--surface); box-shadow: 0 1px 2px rgba(20,30,44,0.05), 0 8px 24px -16px rgba(20,30,44,0.4);
}
.flip .face .lab {
  font: 600 0.62rem/1 var(--font-display); letter-spacing: 0.14em; text-transform: uppercase;
  margin-bottom: 0.5rem;
}
.flip .front { border-left: 4px solid var(--indigo); }
.flip .front .lab { color: var(--indigo); }
.flip .front .q { font: 600 1.02rem/1.35 var(--font-body); color: var(--ink); }
.flip .front .hint { margin-top: auto; font: 400 0.72rem/1.4 var(--font-mono); color: var(--ink-faint); padding-top: 0.6rem; }
.flip .back { transform: rotateY(180deg); border-left: 4px solid var(--amber); background: var(--surface-2); }
.flip .back .lab { color: var(--amber-deep); }
.flip .back .a { font: 400 0.95rem/1.5 var(--font-body); color: var(--ink-soft); overflow: auto; }
@media (prefers-reduced-motion: reduce) { .flip .fp { transition: none; } }

.filter-input {
  flex: 1; min-width: 220px; font: 400 0.95rem/1.4 var(--font-body); color: var(--ink);
  background: var(--surface); border: 1px solid var(--border-strong); border-radius: 999px;
  padding: 0.6rem 1rem; outline: none;
}
.filter-input:focus { border-color: var(--indigo); box-shadow: 0 0 0 3px rgba(79,70,229,0.15); }
.filter-count { font: 500 0.85rem/1 var(--font-mono); color: var(--ink-faint); white-space: nowrap; }

/* glossary grid — reuses tokens */
.gloss { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px,1fr)); gap: 0.7rem; margin-top: 0.4rem; }
.gloss .term { border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 0.7rem 0.85rem; background: var(--surface); }
.gloss .term b { display: block; font: 600 0.98rem/1.3 var(--font-display); color: var(--ink); margin-bottom: 0.15rem; }
.gloss .term span { font: 400 0.86rem/1.45 var(--font-body); color: var(--ink-soft); }

/* interactive checklist */
.checklist { list-style: none; margin: 0.6rem 0 0; padding: 0; display: grid; grid-template-columns: 1fr 1fr; gap: 0.55rem 1.4rem; }
@media (max-width: 640px) { .checklist { grid-template-columns: 1fr; } }
.checklist li { display: flex; gap: 0.7rem; align-items: flex-start; }
.checklist input { appearance: none; -webkit-appearance: none; flex: 0 0 auto; width: 20px; height: 20px; margin-top: 2px; border: 2px solid var(--border-strong); border-radius: 6px; cursor: pointer; position: relative; background: var(--surface); }
.checklist input:checked { background: var(--indigo); border-color: var(--indigo); }
.checklist input:checked::after { content: "✓"; position: absolute; inset: 0; display: grid; place-items: center; color: #fff; font-size: 0.8rem; font-weight: 700; }
.checklist input:focus-visible { outline: 2px solid var(--indigo); outline-offset: 2px; }
.checklist label { font: 400 0.96rem/1.4 var(--font-body); color: var(--ink); cursor: pointer; }
.checklist input:checked + label { color: var(--ink-faint); text-decoration: line-through; text-decoration-color: var(--border-strong); }
.checklist-phase { grid-column: 1 / -1; margin: 0.7rem 0 0.1rem; font: 600 0.68rem/1 var(--font-display); letter-spacing: 0.14em; text-transform: uppercase; color: var(--indigo); }

/* ============================================================
   Flashcards polish — filter chips, shuffle/count toolbar,
   refined flip cards. Uses the existing design tokens.
   ============================================================ */
.fc-chips { display: flex; flex-wrap: wrap; gap: 0.4rem; margin: 0.2rem 0 0.75rem; }
.fc-chip {
  font: 500 0.72rem/1 var(--font-body); color: var(--ink-soft);
  background: var(--surface); border: 1px solid var(--border-strong);
  border-radius: 99px; padding: 0.38rem 0.8rem; cursor: pointer;
  transition: background .12s, border-color .12s, color .12s;
}
.fc-chip:hover { border-color: var(--indigo); color: var(--ink); }
.fc-chip.on { background: var(--indigo); border-color: var(--indigo); color: #fff; }
.fc-chip:focus-visible { outline: 2px solid var(--indigo); outline-offset: 2px; }
.fc-btn {
  font: 500 0.72rem/1 var(--font-body); color: var(--ink-soft);
  background: var(--surface); border: 1px solid var(--border-strong);
  border-radius: 99px; padding: 0.5rem 0.9rem; cursor: pointer; white-space: nowrap;
}
.fc-btn:hover { border-color: var(--indigo); color: var(--ink); }
.fc-btn:focus-visible { outline: 2px solid var(--indigo); outline-offset: 2px; }
.fc-count { font: 500 0.82rem/1 var(--font-mono); color: var(--ink-faint); margin-left: auto; white-space: nowrap; }
.fc-empty {
  display: none; padding: 1.6rem; text-align: center; color: var(--ink-faint);
  font: 400 0.95rem/1.45 var(--font-body); border: 1px dashed var(--border-strong);
  border-radius: var(--radius); margin-top: 0.6rem;
}

/* refined flip cards (overrides the earlier .flip block; later rule wins) */
.flip { height: 212px; transition: transform 0.14s ease; }
.flip:hover { transform: translateY(-3px); }
.flip .face {
  justify-content: flex-start;
  box-shadow: 0 1px 2px rgba(20,30,44,0.05), 0 12px 28px -18px rgba(20,30,44,0.55);
}
.flip .front .lab, .flip .back .lab { align-self: flex-start; }
.flip .front .q {
  flex: 1; display: flex; align-items: center; margin: 0.15rem 0;
  border: 0; background: none; padding: 0;
  font: 600 1.08rem/1.34 var(--font-display); color: var(--ink);
}
.flip .front .hint { margin-top: auto; }
.flip .back .a { flex: 1; overflow: auto; align-items: flex-start; }