/* KiMiA Sound Design — course styles.
   Studio (dark) follows KiMiA's Graphite Orange theme; Paper (light) is for reading and print. */

:root {
  --bg: #141416; --bg-2: #18181B; --surface: #1D1D21; --card: #242429; --raised: #33333B; --button: #3B3B45;
  --line: rgba(255,255,255,.08); --line-strong: rgba(255,255,255,.16);
  --text: #F1EEE9; --text-2: #D5D2CC; --muted: #A3A8B2; --faint: #888D9A;
  --accent: #FFB04A; --accent-ink: #20170D; --accent-text: #FFB866; --accent-soft: rgba(255,176,74,.12);
  --lav: #C7AAFF; --lav-soft: rgba(199,170,255,.13); --teal: #7FD4C1; --teal-soft: rgba(127,212,193,.12); --rose: #FF8FA3; --rose-soft: rgba(255,143,163,.12);
  --fig-bg: #0B0B10; --fig-grid: rgba(255,255,255,.07); --fig-zero: rgba(255,255,255,.18); --fig-label: #8E929C;
  --fig-after: #FFB04A; --fig-before: #C7AAFF; --fig-third: #7FD4C1; --fig-curve: #F4EDE4; --fig-area: rgba(255,176,74,.13);
  --fig-mark: rgba(244,237,228,.55); --fig-chip: #2A2A31; --fig-chip-text: #F4EDE4; --fig-text: #E9E6E1; --fig-glow: .22;
  --fig-key-white: #D9D6D1; --fig-key-black: #141418; --fig-key-line: rgba(0,0,0,.35);
  --shadow: 0 1px 0 rgba(255,255,255,.04) inset, 0 12px 40px rgba(0,0,0,.35);
  --radius: 16px; --radius-sm: 10px;
  --font: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  --font-head: Sora, Inter, -apple-system, system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, monospace;
  --top: 60px; --side: 290px; --col: 740px;
  color-scheme: dark;
}
@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) {
    --bg: #F6F4F0; --bg-2: #EFECE6; --surface: #FFFFFF; --card: #FFFFFF; --raised: #F1EEE9; --button: #E9E5DE;
    --line: rgba(24,24,27,.10); --line-strong: rgba(24,24,27,.18);
    --text: #1B1B1F; --text-2: #34343A; --muted: #5F636C; --faint: #6A6D74;
    --accent: #FFB04A; --accent-ink: #20170D; --accent-text: #A65A00; --accent-soft: rgba(224,124,0,.10);
    --lav: #7A5AD8; --lav-soft: rgba(122,90,216,.10); --teal: #1A7B69; --teal-soft: rgba(30,140,119,.10); --rose: #C8385A; --rose-soft: rgba(200,56,90,.09);
    --fig-bg: #FFFFFF; --fig-grid: rgba(20,20,24,.07); --fig-zero: rgba(20,20,24,.22); --fig-label: #71757E;
    --fig-after: #E07C00; --fig-before: #7A5AD8; --fig-third: #1A7B69; --fig-curve: #2B2B30; --fig-area: rgba(224,124,0,.10);
    --fig-mark: rgba(30,30,35,.45); --fig-chip: #F1EEE9; --fig-chip-text: #1B1B1F; --fig-text: #2B2B30; --fig-glow: .12;
    --fig-key-white: #FFFFFF; --fig-key-black: #2B2B30; --fig-key-line: rgba(20,20,24,.28);
    --shadow: 0 1px 2px rgba(20,20,24,.06), 0 10px 30px rgba(20,20,24,.07);
    color-scheme: light;
  }
}
:root[data-theme="light"] {
  --bg: #F6F4F0; --bg-2: #EFECE6; --surface: #FFFFFF; --card: #FFFFFF; --raised: #F1EEE9; --button: #E9E5DE;
  --line: rgba(24,24,27,.10); --line-strong: rgba(24,24,27,.18);
  --text: #1B1B1F; --text-2: #34343A; --muted: #5F636C; --faint: #6A6D74;
  --accent: #FFB04A; --accent-ink: #20170D; --accent-text: #A65A00; --accent-soft: rgba(224,124,0,.10);
  --lav: #7A5AD8; --lav-soft: rgba(122,90,216,.10); --teal: #1A7B69; --teal-soft: rgba(30,140,119,.10); --rose: #C8385A; --rose-soft: rgba(200,56,90,.09);
  --fig-bg: #FFFFFF; --fig-grid: rgba(20,20,24,.07); --fig-zero: rgba(20,20,24,.22); --fig-label: #71757E;
  --fig-after: #E07C00; --fig-before: #7A5AD8; --fig-third: #1A7B69; --fig-curve: #2B2B30; --fig-area: rgba(224,124,0,.10);
  --fig-mark: rgba(30,30,35,.45); --fig-chip: #F1EEE9; --fig-chip-text: #1B1B1F; --fig-text: #2B2B30; --fig-glow: .12;
    --fig-key-white: #FFFFFF; --fig-key-black: #2B2B30; --fig-key-line: rgba(20,20,24,.28);
  --shadow: 0 1px 2px rgba(20,20,24,.06), 0 10px 30px rgba(20,20,24,.07);
  color-scheme: light;
}
:root[data-theme="dark"] { color-scheme: dark; }

/* theme-specific elements */
.only-light { display: none; }
@media (prefers-color-scheme: light) { :root:not([data-theme="dark"]) .only-light { display: inline; } :root:not([data-theme="dark"]) .only-dark { display: none; } }
:root[data-theme="light"] .only-light { display: inline; }
:root[data-theme="light"] .only-dark { display: none; }

*, *::before, *::after { box-sizing: border-box; }
html { scroll-padding-top: calc(var(--top) + 20px); -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--text); font: 400 17px/1.7 var(--font); -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility; }
a { color: var(--accent-text); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
img, svg { max-width: 100%; }
button { font: inherit; color: inherit; }
::selection { background: rgba(255,176,74,.35); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 6px; }

/* ------------------------------------------------------------ top bar */
.topbar { position: sticky; top: 0; z-index: 30; height: var(--top); display: flex; align-items: center; gap: 14px; padding: 0 18px;
  background: color-mix(in srgb, var(--bg) 82%, transparent); backdrop-filter: saturate(1.4) blur(14px); -webkit-backdrop-filter: saturate(1.4) blur(14px); border-bottom: 1px solid var(--line); }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--text); flex: none; }
.brand svg { width: 30px; height: 30px; }
.brand-name { font: 700 19px/1 var(--font-head); letter-spacing: .01em; }
.brand-sub { font: 500 13px/1 var(--font); color: var(--muted); padding-left: 10px; border-left: 1px solid var(--line-strong); }
.crumbs { display: flex; align-items: center; gap: 8px; min-width: 0; font-size: 13.5px; color: var(--muted); margin-left: 12px; }
.crumbs a { color: var(--muted); text-decoration: none; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.crumbs a:hover { color: var(--text); }
.crumbs i { font-style: normal; color: var(--faint); }
.topbar-end { margin-left: auto; display: flex; align-items: center; gap: 10px; }
.icon-btn { display: inline-grid; place-items: center; width: 38px; height: 38px; border-radius: 10px; border: 1px solid var(--line); background: var(--card); cursor: pointer; color: var(--text-2); }
.icon-btn:hover { border-color: var(--line-strong); color: var(--text); }
.icon-btn svg { width: 20px; height: 20px; }
.nav-toggle { display: none; }
.progress-pill { display: flex; align-items: center; gap: 8px; padding: 4px 12px 4px 5px; border: 1px solid var(--line); border-radius: 99px; background: var(--card); font: 600 13px/1 var(--font-mono); color: var(--text-2); }
.progress-ring svg { width: 28px; height: 28px; transform: rotate(-90deg); display: block; }
.ring-bg { fill: none; stroke: var(--line-strong); stroke-width: 4; }
.ring-fg { fill: none; stroke: var(--accent); stroke-width: 4; stroke-linecap: round; stroke-dasharray: 94.2; stroke-dashoffset: 94.2; transition: stroke-dashoffset .6s ease; }

/* ------------------------------------------------------------ shell */
.shell { display: grid; grid-template-columns: var(--side) minmax(0, 1fr); }
.sidebar { position: sticky; top: var(--top); height: calc(100vh - var(--top)); overflow-y: auto; border-right: 1px solid var(--line); background: var(--bg-2); scrollbar-width: thin; }
.side-inner { padding: 22px 14px 40px; }
.side-level { margin-bottom: 18px; }
.side-level-name { font: 600 11.5px/1.3 var(--font); letter-spacing: .08em; text-transform: uppercase; color: var(--muted); padding: 0 10px 8px; }
.side-level-name span { display: block; color: var(--accent-text); font-family: var(--font-mono); letter-spacing: .04em; margin-bottom: 2px; }
.sidebar ul, .sidebar ol { list-style: none; margin: 0; padding: 0; }
.side-mod > a, .side-soon { display: flex; align-items: baseline; gap: 10px; padding: 7px 10px; border-radius: 9px; text-decoration: none; color: var(--text-2); font-size: 14.5px; line-height: 1.35; }
.side-mod > a:hover { background: var(--card); color: var(--text); }
.side-mod.is-here > a { background: var(--card); color: var(--text); box-shadow: inset 3px 0 0 var(--accent); }
.mod-n { font: 600 12px/1 var(--font-mono); color: var(--faint); flex: none; width: 20px; }
.side-mod.is-here .mod-n { color: var(--accent-text); }
.side-soon { color: var(--faint); cursor: default; }
.side-soon em { margin-left: auto; font-style: normal; font-size: 10.5px; letter-spacing: .06em; text-transform: uppercase; color: var(--faint); border: 1px solid var(--line); padding: 1px 6px; border-radius: 99px; }
.side-lessons { margin: 4px 0 8px 30px !important; border-left: 1px solid var(--line); }
.side-lessons a { display: flex; gap: 8px; align-items: baseline; padding: 6px 10px; font-size: 13.5px; line-height: 1.35; color: var(--muted); text-decoration: none; border-radius: 0 8px 8px 0; }
.side-lessons a:hover { color: var(--text); background: var(--card); }
.side-lessons a[aria-current="page"] { color: var(--text); font-weight: 600; background: var(--accent-soft); box-shadow: inset 2px 0 0 var(--accent); }
.done-dot { flex: none; width: 15px; height: 15px; border-radius: 50%; border: 1.5px solid var(--line-strong); display: inline-grid; place-items: center; transform: translateY(2px); }
.done-dot svg { width: 10px; height: 10px; opacity: 0; color: var(--accent-ink); }
.is-done .done-dot { background: var(--accent); border-color: var(--accent); }
.is-done .done-dot svg { opacity: 1; }

.main { display: grid; grid-template-columns: minmax(0, 1fr); justify-items: center; padding: 0 28px 80px; min-width: 0; overflow-x: clip; } /* the title wave may bleed into the margins, never past the page */
.lesson { width: 100%; max-width: var(--col); min-width: 0; }

/* ------------------------------------------------------------ lesson header */
.lesson-head { position: relative; padding: 56px 0 30px; margin-bottom: 26px; border-bottom: 1px solid var(--line); }
.head-wave { position: absolute; inset: 18px -8% auto -8%; height: 150px; opacity: .55; pointer-events: none; z-index: -1; -webkit-mask-image: linear-gradient(90deg, transparent, #000 25%, #000 75%, transparent); mask-image: linear-gradient(90deg, transparent, #000 25%, #000 75%, transparent); }
.head-wave svg, .hero-wave svg, .cover-wave svg { width: 100%; height: 100%; display: block; }
.hw1 { fill: none; stroke: var(--lav); stroke-width: 2; opacity: .35; vector-effect: non-scaling-stroke; }
.hw2 { fill: none; stroke: var(--accent); stroke-width: 2.5; opacity: .6; vector-effect: non-scaling-stroke; }
.kicker { font: 600 12.5px/1 var(--font-mono); letter-spacing: .08em; text-transform: uppercase; color: var(--accent-text); margin-bottom: 16px; }
.lesson-head h1 { font: 650 clamp(32px, 4.6vw, 48px)/1.08 var(--font-head); letter-spacing: -.02em; margin: 0 0 16px; text-wrap: balance; }
.deck { font-size: 20px; line-height: 1.55; color: var(--text-2); margin: 0 0 22px; text-wrap: pretty; }
.meta { display: flex; flex-wrap: wrap; gap: 8px 18px; font-size: 14px; color: var(--muted); margin-bottom: 26px; }
.meta span { display: inline-flex; align-items: center; gap: 7px; }
.meta svg { width: 17px; height: 17px; color: var(--accent-text); }
.goals { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 22px; box-shadow: var(--shadow); }
.goals-title { font: 600 12px/1 var(--font); letter-spacing: .08em; text-transform: uppercase; color: var(--muted); margin-bottom: 12px; }
.goals ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; }
.goals li { display: flex; gap: 11px; align-items: flex-start; font-size: 16px; line-height: 1.5; }
.goals svg { flex: none; width: 20px; height: 20px; padding: 3px; border-radius: 50%; background: var(--accent-soft); color: var(--accent-text); margin-top: 1px; }

/* ------------------------------------------------------------ body text */
.lesson-body > h2 { font: 650 28px/1.2 var(--font-head); letter-spacing: -.015em; margin: 64px 0 16px; display: flex; align-items: baseline; gap: 14px; text-wrap: balance; }
.lesson-body > h2 .n { font: 600 14px/1 var(--font-mono); color: var(--accent-text); background: var(--accent-soft); border: 1px solid color-mix(in srgb, var(--accent) 30%, transparent); padding: 6px 8px; border-radius: 8px; transform: translateY(-4px); flex: none; }
.lesson-body h3 { font: 600 20px/1.3 var(--font-head); margin: 36px 0 10px; }
.lesson-body p { margin: 0 0 18px; color: var(--text-2); text-wrap: pretty; }
.lesson-body strong { color: var(--text); font-weight: 650; }
.lesson-body ul, .lesson-body ol { color: var(--text-2); padding-left: 1.3em; margin: 0 0 18px; }
.lesson-body li { margin-bottom: 7px; }
.lesson-body li::marker { color: var(--accent-text); }
.lead { font-size: 19px; color: var(--text) !important; }
.term { font-weight: 600; color: var(--text); background: linear-gradient(transparent 62%, var(--accent-soft) 62%); padding: 0 2px; }
kbd, .val { font: 600 .86em/1 var(--font-mono); background: var(--card); border: 1px solid var(--line-strong); border-bottom-width: 2px; border-radius: 6px; padding: 3px 6px; color: var(--text); white-space: nowrap; }
.uipath { display: inline-flex; flex-wrap: wrap; align-items: center; gap: 4px; font: 600 .84em/1 var(--font); vertical-align: 1px; }
.uipath span { background: var(--card); border: 1px solid var(--line-strong); border-radius: 6px; padding: 4px 7px; color: var(--text); white-space: nowrap; }
.uipath i { font-style: normal; color: var(--faint); }
hr.soft { border: 0; height: 1px; background: var(--line); margin: 40px 0; }

/* ------------------------------------------------------------ callouts */
.note { position: relative; margin: 26px 0; padding: 18px 20px 18px 58px; border-radius: var(--radius); background: var(--card); border: 1px solid var(--line); }
.note::before { content: ""; position: absolute; left: 18px; top: 19px; width: 26px; height: 26px; border-radius: 8px; background: var(--accent-soft) center/16px no-repeat; }
.note-title { display: block; font: 700 12px/1.2 var(--font); letter-spacing: .08em; text-transform: uppercase; margin-bottom: 6px; color: var(--accent-text); }
.note p:last-child { margin-bottom: 0; }
.note p { font-size: 16px; }
.note.keys { background: linear-gradient(0deg, var(--lav-soft), var(--lav-soft)), var(--card); border-color: color-mix(in srgb, var(--lav) 28%, transparent); }
.note.keys .note-title { color: var(--lav); }
.note.keys::before { background-color: var(--lav-soft); background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Crect x='2.5' y='5' width='19' height='14' rx='2' fill='none' stroke='%23B69CF5' stroke-width='1.7'/%3E%3Cpath d='M5.2 5h3.4v8H5.2zM10.3 5h3.4v8h-3.4zM15.4 5h3.4v8h-3.4z' fill='%23B69CF5'/%3E%3C/svg%3E"); }
.note.tip::before { background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M9 18h6M10 21h4M12 3a6 6 0 0 0-3.5 10.9c.6.5 1 1.2 1 2V16h5v-.1c0-.8.4-1.5 1-2A6 6 0 0 0 12 3z' fill='none' stroke='%23F0A040' stroke-width='1.8' stroke-linejoin='round'/%3E%3C/svg%3E"); }
.note.warn { background: linear-gradient(0deg, var(--rose-soft), var(--rose-soft)), var(--card); border-color: color-mix(in srgb, var(--rose) 28%, transparent); }
.note.warn .note-title { color: var(--rose); }
.note.warn::before { background-color: var(--rose-soft); background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M12 4l9 16H3z' fill='none' stroke='%23E8687F' stroke-width='1.8' stroke-linejoin='round'/%3E%3Cpath d='M12 10v4M12 17v.5' stroke='%23E8687F' stroke-width='1.9' stroke-linecap='round'/%3E%3C/svg%3E"); }
.note.kimia::before { background-color: var(--accent); background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M3 12c1.5-5 3-5 4.5 0s3 5 4.5 0 3-5 4.5 0 3 5 4.5 0' fill='none' stroke='%2320170D' stroke-width='2.2' stroke-linecap='round'/%3E%3C/svg%3E"); }
.note.future { background: linear-gradient(0deg, var(--teal-soft), var(--teal-soft)), var(--card); border-color: color-mix(in srgb, var(--teal) 30%, transparent); }
.note.future .note-title { color: var(--teal); }
.note.future::before { background-color: var(--teal-soft); background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M12 3l2.6 5.6 6 .7-4.5 4.1 1.2 6L12 16.4 6.7 19.4l1.2-6L3.4 9.3l6-.7z' fill='none' stroke='%2350B8A2' stroke-width='1.7' stroke-linejoin='round'/%3E%3C/svg%3E"); }
details.theory { margin: 26px 0; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
details.theory summary { cursor: pointer; list-style: none; padding: 16px 20px; font-weight: 600; display: flex; align-items: center; gap: 10px; color: var(--text); }
details.theory summary::-webkit-details-marker { display: none; }
details.theory summary::before { content: "+"; display: inline-grid; place-items: center; width: 24px; height: 24px; border-radius: 7px; background: var(--raised); font: 600 16px/1 var(--font-mono); color: var(--accent-text); transition: transform .2s; }
details.theory[open] summary::before { content: "−"; }
details.theory summary small { font-weight: 500; color: var(--muted); margin-left: auto; font-size: 12.5px; letter-spacing: .06em; text-transform: uppercase; }
details.theory > div { padding: 0 20px 6px; }
details.theory p { font-size: 16px; }

/* ------------------------------------------------------------ figures */
/* chart marks (shared with tools/figures.mjs) */
.fg-bg{fill:var(--fig-bg,#0B0B10)}.fg-grid{stroke:var(--fig-grid,rgba(255,255,255,.07));stroke-width:1}
.fg-zero{stroke:var(--fig-zero,rgba(255,255,255,.18));stroke-width:1}.fg-label{fill:var(--fig-label,#8E929C);font:500 11px/1 Inter,system-ui,sans-serif;font-variant-numeric:tabular-nums}
.fg-after{stroke:var(--fig-after,#FFB04A);fill:none;stroke-width:2.2;stroke-linejoin:round;stroke-linecap:round}
.fg-before{stroke:var(--fig-before,#C7AAFF);fill:none;stroke-width:1.6;stroke-linejoin:round;stroke-linecap:round}
.fg-third{stroke:var(--fig-third,#7FD4C1);fill:none;stroke-width:1.8;stroke-linejoin:round;stroke-linecap:round}
.fg-quad{stroke:var(--rose,#FF8FA3);fill:none;stroke-width:1.8;stroke-linejoin:round;stroke-linecap:round}
.fg-glow{stroke:var(--fig-after,#FFB04A);fill:none;stroke-width:6;opacity:var(--fig-glow,.22);stroke-linejoin:round}
.fg-curve{stroke:var(--fig-curve,#F4EDE4);fill:none;stroke-width:1.8;stroke-linejoin:round}
.fg-area{fill:var(--fig-area,rgba(255,176,74,.13))}.fg-mark{stroke:var(--fig-mark,rgba(244,237,228,.55));stroke-width:1.2;stroke-dasharray:3 4}
.fg-chip{fill:var(--fig-chip,#242429)}.fg-chip-text{fill:var(--fig-chip-text,#F4EDE4);font:600 11px/1 Inter,system-ui,sans-serif}
.fg-dot-after{fill:var(--fig-after,#FFB04A)}.fg-dot-before{fill:var(--fig-before,#C7AAFF)}.fg-dot-third{fill:var(--fig-third,#7FD4C1)}.fg-dot-quad{fill:var(--rose,#FF8FA3)}
.fg-fill-after{fill:var(--fig-after,#FFB04A);opacity:.85}.fg-fill-before{fill:var(--fig-before,#C7AAFF);opacity:.5}
.fg-text{fill:var(--fig-text,#E9E6E1);font:600 12px/1 Inter,system-ui,sans-serif}
.fx { margin: 34px 0; padding: 16px; background: var(--surface); border: 1px solid var(--line); border-radius: calc(var(--radius) + 4px); box-shadow: var(--shadow); }
.fx-wide { margin-left: clamp(-120px, calc((var(--col) - 100vw) / 2 + 190px), 0px); margin-right: clamp(-120px, calc((var(--col) - 100vw) / 2 + 190px), 0px); }
.fx-head { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 12px; padding: 2px 4px 14px; }
.fx-num { font: 600 11.5px/1 var(--font-mono); letter-spacing: .06em; text-transform: uppercase; color: var(--accent-text); flex: none; }
.fx-title { font: 600 16.5px/1.35 var(--font-head); margin: 0; flex: 1 1 280px; color: var(--text); }
.fx-chips { display: flex; flex-wrap: wrap; gap: 6px; width: 100%; }
.chip { display: inline-flex; align-items: center; gap: 7px; font: 600 12px/1 var(--font); padding: 6px 10px; border-radius: 99px; background: var(--card); border: 1px solid var(--line); color: var(--text-2); }
.chip::before { content: ""; width: 8px; height: 8px; border-radius: 50%; background: var(--accent); }
.chip-before::before { background: var(--fig-before); }
.chip-third::before { background: var(--fig-third); }
.chip-quad::before { background: var(--rose); }
.fx-grid { display: grid; gap: 12px; }
.fx-two { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.fx-three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.fx-four { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.fx-span { grid-column: 1 / -1; } /* a panel across the whole figure, under the others */
.fx-panel { min-width: 0; }
.fx-label { font: 500 12.5px/1.3 var(--font); color: var(--muted); margin: 0 4px 7px; }
.fx svg.fg { width: 100%; height: auto; display: block; border-radius: 10px; }
:root[data-theme="light"] .fx svg.fg { outline: 1px solid var(--line); outline-offset: -1px; }
@media (prefers-color-scheme: light) { :root:not([data-theme="dark"]) .fx svg.fg { outline: 1px solid var(--line); outline-offset: -1px; } }
.fx figcaption { font-size: 15px; line-height: 1.6; color: var(--muted); padding: 12px 4px 2px; text-wrap: pretty; }
.fx-illo { margin: 12px 0 0; display: grid; place-items: center; }
.fx-illo svg { width: 100%; height: auto; max-width: 640px; }
.fx-illo-fig .fx-illo svg { max-width: 460px; }
.fx-panel, .fx-illo { cursor: zoom-in; }

/* ------------------------------------------------------------ A/B player */
.ab { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin: 14px 0 2px; padding: 10px; border-radius: 14px; background: var(--card); border: 1px solid var(--line); }
.lesson-body > .ab { margin: 18px 0 24px; }
.ab-btn { --c: var(--fig-after); display: inline-flex; align-items: center; gap: 9px; padding: 9px 14px 9px 10px; border-radius: 10px; border: 1px solid var(--line-strong); background: var(--surface); cursor: pointer; font: 600 14px/1.2 var(--font); color: var(--text); text-align: left; transition: border-color .15s, background .15s, box-shadow .15s; }
.ab-before { --c: var(--fig-before); } .ab-third { --c: var(--fig-third); } .ab-quad { --c: var(--rose); }
.ab-btn:hover { border-color: var(--c); }
.ab-icon { flex: none; width: 24px; height: 24px; border-radius: 50%; background: var(--c); position: relative; }
.ab-icon::after { content: ""; position: absolute; left: 9px; top: 7px; border-left: 8px solid var(--accent-ink); border-top: 5px solid transparent; border-bottom: 5px solid transparent; }
.ab-btn.is-playing { background: color-mix(in srgb, var(--c) 16%, var(--surface)); border-color: var(--c); box-shadow: 0 0 0 3px color-mix(in srgb, var(--c) 20%, transparent); }
.ab-btn.is-playing .ab-icon::after { left: 8px; top: 7.5px; width: 3px; height: 9px; border: 0; background: var(--accent-ink); box-shadow: 5px 0 0 var(--accent-ink); }
.ab-note { font-size: 12.5px; color: var(--faint); margin-left: auto; padding-right: 4px; }
.ab-progress { flex-basis: 100%; height: 3px; border-radius: 3px; background: var(--line); overflow: hidden; }
.ab-progress i { display: block; height: 100%; width: 0; background: var(--accent); }
.print-only { display: none; }

/* ------------------------------------------------------------ scrubber */
.scrub-ctl { display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: center; gap: 10px 16px; margin-top: 14px; padding: 14px 16px; background: var(--card); border: 1px solid var(--line); border-radius: 14px; }
.scrub-name { font-weight: 600; color: var(--muted); font-size: 15px; }
.scrub-value { font: 600 18px/1 var(--font-mono); color: var(--text); min-width: 88px; text-align: right; }
.scrub-listen { grid-column: 1 / -1; justify-self: start; display: inline-flex; align-items: center; gap: 9px; padding: 7px 12px 7px 8px; border-radius: 10px; border: 1px solid var(--line-strong); background: var(--surface); cursor: pointer; font-size: 13.5px; font-weight: 600; --c: var(--fig-after); }
.scrub-listen[aria-pressed="true"] { border-color: var(--accent); background: var(--accent-soft); }
input[type="range"].scrub-range { -webkit-appearance: none; appearance: none; width: 100%; height: 28px; background: transparent; cursor: pointer; }
.scrub-range::-webkit-slider-runnable-track { height: 6px; border-radius: 3px; background: linear-gradient(90deg, var(--accent) var(--fill, 0%), var(--button) var(--fill, 0%)); }
.scrub-range::-moz-range-track { height: 6px; border-radius: 3px; background: var(--button); }
.scrub-range::-moz-range-progress { height: 6px; border-radius: 3px; background: var(--accent); }
.scrub-range::-webkit-slider-thumb { -webkit-appearance: none; width: 22px; height: 22px; border-radius: 50%; background: #F4F2EE; border: 1px solid rgba(0,0,0,.25); margin-top: -8px; box-shadow: 0 2px 8px rgba(0,0,0,.35); }
.scrub-range::-moz-range-thumb { width: 22px; height: 22px; border-radius: 50%; background: #F4F2EE; border: 1px solid rgba(0,0,0,.25); box-shadow: 0 2px 8px rgba(0,0,0,.35); }
.scrub-ticks { grid-column: 2; display: flex; justify-content: space-between; font: 500 11px/1 var(--font-mono); color: var(--faint); margin-top: -6px; }

/* ------------------------------------------------------------ signal journey */
.fx-journey .fx-head { align-items: center; }
.journey-play { margin-left: auto; display: inline-flex; align-items: center; gap: 9px; padding: 8px 14px 8px 9px; border-radius: 10px; border: 1px solid var(--accent); background: var(--accent-soft); cursor: pointer; font-weight: 600; font-size: 14px; --c: var(--fig-after); }
.journey { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); grid-auto-rows: auto; column-gap: 22px; row-gap: 0; counter-reset: st; }
.stage { position: relative; display: grid; grid-row: span 5; grid-template-rows: subgrid; row-gap: 7px; margin-bottom: 14px; padding: 10px; border-radius: 14px; background: var(--card); border: 1px solid var(--line); transition: border-color .25s, box-shadow .25s, transform .25s; }
.stage:not(:last-child)::after { content: ""; position: absolute; right: -19px; top: 50%; width: 16px; height: 2px; background: var(--line-strong); }
.stage:not(:last-child)::before { content: ""; position: absolute; right: -19px; top: calc(50% - 4px); border-left: 7px solid var(--line-strong); border-top: 5px solid transparent; border-bottom: 5px solid transparent; transform: translateX(10px); }
.stage-focus { border-color: color-mix(in srgb, var(--accent) 55%, transparent); box-shadow: 0 0 0 3px var(--accent-soft); }
.stage.is-active { border-color: var(--accent); box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 30%, transparent), 0 10px 30px rgba(0,0,0,.25); transform: translateY(-3px); }
.stage-top { display: flex; align-items: center; gap: 7px; }
.stage-n { flex: none; display: inline-grid; place-items: center; width: 20px; height: 20px; border-radius: 6px; background: var(--raised); font: 600 11px/1 var(--font-mono); color: var(--accent-text); }
.stage-focus .stage-n, .stage.is-active .stage-n { background: var(--accent); color: var(--accent-ink); }
.stage-name { font: 600 13px/1.25 var(--font-head); color: var(--text); }
.stage-detail { font-size: 11.5px; line-height: 1.4; color: var(--muted); min-height: 3.2em; }
.stage svg { width: 100%; height: auto; display: block; }
.stage-listen { justify-self: start; align-self: end; display: inline-flex; align-items: center; gap: 7px; padding: 4px 10px 4px 4px; border-radius: 99px; border: 1px solid var(--line-strong); background: var(--surface); cursor: pointer; font-size: 12px; font-weight: 600; --c: var(--fig-after); }
.stage-listen .ab-icon { width: 20px; height: 20px; }
.stage-listen .ab-icon::after { left: 7.5px; top: 5.5px; border-left-width: 7px; border-top-width: 4.5px; border-bottom-width: 4.5px; }

/* ------------------------------------------------------------ steps, tables, quiz */
ol.steps { list-style: none; counter-reset: step; padding: 0; margin: 20px 0 26px; display: grid; gap: 12px; }
ol.steps > li { counter-increment: step; position: relative; padding: 14px 18px 14px 58px; background: var(--card); border: 1px solid var(--line); border-radius: 14px; margin: 0; color: var(--text-2); }
ol.steps > li::before { content: counter(step); position: absolute; left: 16px; top: 13px; width: 28px; height: 28px; border-radius: 50%; background: var(--accent); color: var(--accent-ink); display: grid; place-items: center; font: 700 14px/1 var(--font-mono); }
ol.steps > li strong { color: var(--text); }
.table-wrap { overflow-x: auto; margin: 22px 0 28px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
table.nice { width: 100%; border-collapse: collapse; font-size: 15px; min-width: 520px; }
table.nice th, table.nice td { text-align: left; padding: 11px 14px; border-bottom: 1px solid var(--line); vertical-align: top; }
table.nice th { font: 600 12px/1.3 var(--font); letter-spacing: .06em; text-transform: uppercase; color: var(--muted); background: var(--card); }
table.nice tr:last-child td { border-bottom: 0; }
table.nice td:first-child { font-weight: 600; color: var(--text); white-space: nowrap; }
table.nice td { color: var(--text-2); }
.swatch { display: inline-block; width: 10px; height: 10px; border-radius: 3px; margin-right: 7px; vertical-align: 0; }

.quiz { margin: 30px 0; display: grid; gap: 14px; }
.q { padding: 18px 20px; border-radius: var(--radius); background: var(--card); border: 1px solid var(--line); }
.q-text { font-weight: 600; color: var(--text); margin-bottom: 12px; }
.q-text span { font: 600 12px/1 var(--font-mono); color: var(--accent-text); margin-right: 8px; }
.q-options { display: grid; gap: 8px; }
.q-opt { text-align: left; padding: 11px 14px; border-radius: 10px; border: 1px solid var(--line-strong); background: var(--surface); cursor: pointer; font-size: 15.5px; color: var(--text-2); display: flex; gap: 10px; align-items: baseline; }
.q-opt:hover { border-color: var(--accent); color: var(--text); }
.q-opt b { font: 600 12.5px/1 var(--font-mono); color: var(--muted); }
.q-opt.is-right { border-color: var(--teal); background: var(--teal-soft); color: var(--text); }
.q-opt.is-wrong { border-color: var(--rose); background: var(--rose-soft); }
.q-why { display: none; margin-top: 12px; font-size: 15px; color: var(--text-2); padding: 12px 14px; border-radius: 10px; background: var(--surface); border-left: 3px solid var(--teal); }
.q.is-answered .q-why { display: block; }
.q.is-answered .q-opt { cursor: default; }
.workbook-lines { display: none; }

/* ------------------------------------------------------------ lesson end */
.lesson-end { margin-top: 70px; padding-top: 30px; border-top: 1px solid var(--line); display: grid; gap: 22px; }
.complete-btn { justify-self: start; display: inline-flex; align-items: center; gap: 12px; padding: 13px 20px 13px 14px; border-radius: 12px; border: 1px solid var(--line-strong); background: var(--card); cursor: pointer; font-weight: 650; font-size: 15.5px; }
.cb-icon { display: inline-grid; place-items: center; width: 26px; height: 26px; border-radius: 50%; border: 2px solid var(--line-strong); }
.cb-icon svg { width: 15px; height: 15px; opacity: 0; color: var(--accent-ink); }
.complete-btn.is-done { border-color: var(--accent); background: var(--accent-soft); }
.complete-btn.is-done .cb-icon { background: var(--accent); border-color: var(--accent); }
.complete-btn.is-done .cb-icon svg { opacity: 1; }
.pager { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.pager-card { display: grid; gap: 6px; padding: 16px 18px; border-radius: var(--radius); background: var(--card); border: 1px solid var(--line); text-decoration: none; color: var(--text); transition: border-color .15s, transform .15s; }
.pager-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.pager-card.next { text-align: right; }
.pager-dir { display: inline-flex; align-items: center; gap: 4px; font: 600 12px/1 var(--font-mono); letter-spacing: .06em; text-transform: uppercase; color: var(--accent-text); }
.pager-card.next .pager-dir { justify-content: flex-end; }
.pager-dir svg { width: 15px; height: 15px; }
.pager-title { font: 600 16px/1.35 var(--font-head); }

/* ------------------------------------------------------------ table of contents */
.toc { display: none; }
@media (min-width: 1500px) {
  .main { grid-template-columns: minmax(0, 1fr) 230px; justify-items: stretch; column-gap: 40px; }
  .lesson { justify-self: center; }
  .toc { display: block; position: sticky; top: calc(var(--top) + 40px); align-self: start; margin-top: 60px; font-size: 13.5px; }
  .toc-title { font: 600 11.5px/1 var(--font); letter-spacing: .08em; text-transform: uppercase; color: var(--muted); margin-bottom: 12px; }
  .toc-list { list-style: none; padding: 0; margin: 0; border-left: 1px solid var(--line); }
  .toc-list a { display: block; padding: 6px 12px; color: var(--muted); text-decoration: none; line-height: 1.35; margin-left: -1px; border-left: 2px solid transparent; }
  .toc-list a:hover { color: var(--text); }
  .toc-list a.is-active { color: var(--text); border-left-color: var(--accent); }
}

/* ------------------------------------------------------------ module + home pages */
.lesson-body .lesson-cards { list-style: none; padding: 0; margin: 10px 0 30px; display: grid; gap: 12px; }
.lesson-card { display: grid; grid-template-columns: auto minmax(0, 1fr) auto auto; gap: 16px; align-items: center; padding: 18px 20px; border-radius: var(--radius); background: var(--card); border: 1px solid var(--line); text-decoration: none; color: var(--text); transition: border-color .15s, transform .15s; }
.lesson-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.lc-n { font: 600 15px/1 var(--font-mono); color: var(--accent-text); background: var(--accent-soft); padding: 8px 9px; border-radius: 9px; }
.lc-body { display: grid; gap: 4px; }
.lc-title { font: 600 17px/1.3 var(--font-head); }
.lc-goals { font-size: 13.5px; color: var(--muted); line-height: 1.45; }
.lc-min { font: 500 13px/1 var(--font-mono); color: var(--muted); white-space: nowrap; }
.lc-done { width: 24px; height: 24px; border-radius: 50%; border: 2px solid var(--line-strong); display: grid; place-items: center; }
.lc-done svg { width: 14px; height: 14px; opacity: 0; color: var(--accent-ink); }
.is-done .lc-done { background: var(--accent); border-color: var(--accent); }
.is-done .lc-done svg { opacity: 1; }
.downloads { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin: 10px 0 20px; }
.dl-card { display: flex; gap: 14px; align-items: flex-start; padding: 16px 18px; border-radius: var(--radius); background: var(--surface); border: 1px dashed var(--line-strong); text-decoration: none; color: var(--text); }
.dl-card:hover { border-color: var(--accent); border-style: solid; }
.dl-card.is-soon { opacity: .62; }
.dl-card.is-soon:hover { border-color: var(--line-strong); border-style: dashed; }
.dl-card svg { flex: none; width: 34px; height: 34px; padding: 6px; border-radius: 10px; background: var(--accent-soft); color: var(--accent-text); }
.dl-card strong { display: block; font-family: var(--font-head); font-size: 15.5px; margin-bottom: 3px; }
.dl-card span span { font-size: 13.5px; color: var(--muted); line-height: 1.45; }

.home { max-width: 1180px; margin: 0 auto; padding: 0 28px 90px; }
.hero { position: relative; padding: 110px 0 70px; text-align: center; }
.hero-wave { position: absolute; inset: 40px -10% auto -10%; height: 300px; opacity: .6; z-index: -1; pointer-events: none; -webkit-mask-image: radial-gradient(ellipse at center, #000 30%, transparent 72%); mask-image: radial-gradient(ellipse at center, #000 30%, transparent 72%); }
.hero-kicker { font: 600 13px/1 var(--font-mono); letter-spacing: .1em; text-transform: uppercase; color: var(--accent-text); margin-bottom: 22px; }
.hero-title { font: 700 clamp(44px, 8vw, 88px)/1 var(--font-head); letter-spacing: -.035em; margin: 0 0 22px; }
.hero-sub { max-width: 640px; margin: 0 auto 34px; font-size: 20px; line-height: 1.55; color: var(--text-2); text-wrap: balance; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; }
.btn-primary, .btn-ghost { display: inline-flex; align-items: center; padding: 14px 22px; border-radius: 12px; font-weight: 650; text-decoration: none; font-size: 16px; }
.btn-primary { background: var(--accent); color: var(--accent-ink); box-shadow: 0 10px 30px rgba(255,176,74,.25); }
.btn-primary:hover { filter: brightness(1.05); }
.btn-ghost { border: 1px solid var(--line-strong); color: var(--text); }
.btn-ghost:hover { border-color: var(--accent); }
.home-intro { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; margin: 10px 0 70px; }
.intro-card { padding: 22px; border-radius: var(--radius); background: var(--card); border: 1px solid var(--line); }
.intro-card h3 { font: 600 18px/1.3 var(--font-head); margin: 12px 0 8px; }
.intro-card p { margin: 0; color: var(--text-2); font-size: 15.5px; line-height: 1.6; }
.intro-card .fg { width: 100%; height: auto; border-radius: 10px; display: block; }
.level-block { margin: 0 0 54px; }
.level-head { display: grid; grid-template-columns: auto 1fr; column-gap: 18px; align-items: baseline; margin-bottom: 18px; }
.level-n { font: 600 13px/1 var(--font-mono); letter-spacing: .08em; text-transform: uppercase; color: var(--accent-text); }
.level-head h2 { font: 650 28px/1.2 var(--font-head); margin: 0; letter-spacing: -.01em; }
.level-head p { grid-column: 2; margin: 6px 0 0; color: var(--muted); }
.mod-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 14px; }
.mod-card { position: relative; display: grid; gap: 8px; align-content: start; padding: 20px; min-height: 190px; border-radius: var(--radius); background: var(--card); border: 1px solid var(--line); text-decoration: none; color: var(--text); }
.mod-card.is-open { border-color: color-mix(in srgb, var(--accent) 45%, transparent); background: linear-gradient(160deg, var(--accent-soft), transparent 60%), var(--card); transition: transform .15s, border-color .15s; }
.mod-card.is-open:hover { transform: translateY(-3px); border-color: var(--accent); }
.mod-card:not(.is-open) { opacity: .72; }
.mc-n { font: 600 13px/1 var(--font-mono); color: var(--accent-text); }
.mc-title { font: 600 19px/1.25 var(--font-head); }
.mc-blurb { font-size: 14.5px; color: var(--muted); line-height: 1.5; }
.mc-foot { margin-top: auto; padding-top: 10px; font: 600 11.5px/1.3 var(--font); letter-spacing: .06em; text-transform: uppercase; color: var(--faint); }
.mod-card.is-open .mc-foot { color: var(--accent-text); }
.mod-card.is-future .mc-foot { color: var(--teal); }

.site-foot { border-top: 1px solid var(--line); padding: 28px; text-align: center; color: var(--muted); font-size: 14px; display: grid; gap: 6px; }
.foot-small { font-size: 12.5px; color: var(--faint); }

/* ------------------------------------------------------------ KiMiA screenshots */
.shot-pic { position: relative; margin: 0 auto; }
.shot-pic img { display: block; width: 100%; height: auto; border-radius: 8px; background: #15171b; box-shadow: 0 0 0 1px var(--line); }
.shot-band { margin-bottom: 36px; }
.shot-mark { position: absolute; transform: translate(-50%, -50%); width: 26px; height: 26px; border-radius: 50%; background: var(--accent); color: var(--accent-ink);
  font: 700 13px/26px var(--font-mono); text-align: center; box-shadow: 0 0 0 3px rgba(10,12,16,.55), 0 2px 8px rgba(0,0,0,.5); pointer-events: none; }
.shot-legend { list-style: none; counter-reset: mark; margin: 14px 0 0; padding: 0; display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 8px 22px; font-size: 14.5px; }
.shot-legend li { counter-increment: mark; display: flex; gap: 10px; align-items: baseline; margin: 0; }
.shot-legend li::before { content: counter(mark); flex: none; width: 21px; height: 21px; border-radius: 50%; background: var(--accent); color: var(--accent-ink); font: 700 11.5px/21px var(--font-mono); text-align: center; transform: translateY(-1px); }
.shot-legend li > span { flex: 1; min-width: 0; color: var(--text-2); }
.shot-legend strong { color: var(--text); }
.lightbox-body .shot-pic { width: 100%; max-width: none !important; }
@media (max-width: 640px) { .shot-mark { width: 20px; height: 20px; font-size: 11px; line-height: 20px; box-shadow: 0 0 0 2px rgba(10,12,16,.55); } }

/* ------------------------------------------------------------ lightbox */
.lightbox { position: fixed; inset: 0; z-index: 60; background: color-mix(in srgb, var(--bg) 92%, transparent); backdrop-filter: blur(8px); display: grid; place-items: center; padding: 24px; }
.lightbox[hidden] { display: none; }
.lightbox-body { width: min(1400px, 100%); max-height: 100%; overflow: auto; }
.lightbox-body svg { width: 100%; height: auto; display: block; }
.lightbox-close { position: absolute; top: 16px; right: 16px; font-size: 24px; }

/* ------------------------------------------------------------ responsive */
@media (max-width: 1180px) {
  .fx-four { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .journey { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .stage:nth-child(3n)::after, .stage:nth-child(3n)::before { display: none; }
  .fx-wide { margin-left: 0; margin-right: 0; }
}
/* The home page's course map is the phone's drawer only (its own map is the page). */
.sidebar.drawer-only { display: none; }
/* The wide waves behind the headings never let a phone's page slide sideways. */
html, body { overflow-x: clip; }
@media (max-width: 980px) {
  .sidebar.drawer-only { display: block; }
  :root { --top: 56px; }
  .shell { grid-template-columns: minmax(0, 1fr); }
  .nav-toggle { display: inline-grid; }
  .sidebar { position: fixed; top: var(--top); left: 0; bottom: 0; height: auto; width: min(320px, 88vw); z-index: 40; transform: translateX(-100%); visibility: hidden; transition: transform .25s ease, visibility 0s linear .25s; }
  body.nav-open .sidebar { transform: none; visibility: visible; transition: transform .25s ease; box-shadow: 20px 0 60px rgba(0,0,0,.35); }
  .crumbs { display: none; }
  .home-intro { grid-template-columns: minmax(0, 1fr); }
}
@media (max-width: 720px) {
  body { font-size: 16.5px; }
  .main, .home { padding-left: 16px; padding-right: 16px; }
  .brand-sub, .progress-text { display: none; }
  .progress-pill { padding: 4px; }
  .lesson-head { padding-top: 36px; }
  .deck { font-size: 18px; }
  .lesson-body > h2 { font-size: 23px; margin-top: 48px; }
  .fx { padding: 12px; margin-left: -4px; margin-right: -4px; }
  .fx-two, .fx-three { grid-template-columns: minmax(0, 1fr); }
  .fx-four { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .journey { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
  .stage::after, .stage::before { display: none; }
  .ab-note { flex-basis: 100%; margin-left: 4px; }
  .pager, .downloads { grid-template-columns: minmax(0, 1fr); }
  .lesson-card { grid-template-columns: auto minmax(0, 1fr) auto; }
  .lc-min { display: none; }
  .note { padding: 16px 16px 16px 52px; }
  .note::before { left: 14px; }
  .hero { padding-top: 70px; }
  .level-head { grid-template-columns: minmax(0, 1fr); }
  .level-head p { grid-column: 1; }
}
@media (prefers-reduced-motion: reduce) { * { transition: none !important; animation: none !important; } }

/* ------------------------------------------------------------ print (workbook PDF) */
@page { size: A4; margin: 16mm 15mm 18mm; @bottom-center { content: counter(page); font: 9pt Inter, sans-serif; color: #8C9099; } }
@page :first { margin: 0; @bottom-center { content: none; } @bottom-left { content: none; } }
@media print {
  :root { --bg: #fff; --bg-2: #fff; --surface: #fff; --card: #FAF8F5; --raised: #F1EEE9; --button: #E9E5DE; --line: rgba(24,24,27,.12); --line-strong: rgba(24,24,27,.2);
    --text: #16161A; --text-2: #2A2A30; --muted: #585C65; --faint: #6A6D74; --accent-text: #A65A00; --accent-soft: rgba(224,124,0,.10);
    --lav: #6B4BCB; --lav-soft: rgba(122,90,216,.08); --teal: #1A7B69; --teal-soft: rgba(30,140,119,.08); --rose: #C8385A; --rose-soft: rgba(200,56,90,.07);
    --fig-bg: #FFFFFF; --fig-grid: rgba(20,20,24,.08); --fig-zero: rgba(20,20,24,.25); --fig-label: #5F636C; --fig-after: #E07C00; --fig-before: #7A5AD8; --fig-third: #1A7B69;
    --fig-curve: #2B2B30; --fig-area: rgba(224,124,0,.10); --fig-mark: rgba(30,30,35,.5); --fig-chip: #F1EEE9; --fig-chip-text: #1B1B1F; --fig-text: #2B2B30; --fig-glow: 0; --shadow: none; color-scheme: light; }
  .only-dark { display: none !important; } .only-light { display: inline !important; }
  body { font-size: 10.5pt; line-height: 1.55; background: #fff; }
  .fx-scrub, .topbar, .sidebar, .toc, .site-foot, .lesson-end, .lightbox, .scrub-ctl, .journey-play, .stage-listen, .ab-btn, .ab-note, .ab-progress, .head-wave { display: none !important; }
  .shell, .main { display: block; padding: 0; }
  .lesson { max-width: none; }
  .fx { box-shadow: none; break-inside: avoid; margin: 14pt 0; padding: 10pt; border-radius: 10pt; }
  .fx-wide { margin-left: 0; margin-right: 0; }
  .fx svg.fg { outline: 1px solid rgba(20,20,24,.12); outline-offset: -1px; }
  .fx figcaption { font-size: 9pt; }
  .ab { background: none; border: 0; padding: 0; margin: 6pt 0 0; }
  .print-only { display: block; }
  span.print-only { display: inline; }
  .screen-only { display: none !important; }
  .ab-print { font: 600 8.5pt/1.2 var(--font-mono); color: var(--accent-text); }
  .ab-print::before { content: "♪ "; }
  .note, ol.steps > li, .q, .goals, details.theory { break-inside: avoid; }
  .table-wrap { overflow: visible; }
  table.nice { min-width: 0; }
  table.nice tr { break-inside: avoid; }
  .fx-two { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .fx-three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .fx-four { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .fx-grid { gap: 7pt; }
  .fx-label { font-size: 7.5pt; margin: 0 2pt 3pt; }
  .fx-head { padding-bottom: 8pt; }
  .fx-title { font-size: 11.5pt; }
  .chip { font-size: 7.5pt; padding: 3pt 7pt; }
  .fx-illo-fig .fx-illo svg { max-width: 300px; }
  details.theory > div { display: block !important; }
  details.theory summary::before { content: "▸"; }
  .lesson-body > h2 { font-size: 17pt; margin-top: 22pt; break-after: avoid; }
  .lesson-body h3 { break-after: avoid; }
  .lesson-head { padding-top: 0; margin-bottom: 14pt; }
  .lesson-head h1 { font-size: 26pt; }
  .deck { font-size: 12.5pt; }
  .meta { display: none; }
  .print-lesson { break-before: page; }
  .journey { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 8pt; }
  .stage::after, .stage::before { display: none; }
  .q-opt { cursor: default; }
  .q-opt::before { content: ""; width: 10pt; height: 10pt; border: 1.2px solid #8C9099; border-radius: 3px; flex: none; transform: translateY(1pt); }
  .q-why { display: none !important; }
  .workbook-lines { display: block; margin: 8pt 0 14pt; }
  .workbook-lines div { height: 22pt; border-bottom: 1px solid rgba(20,20,24,.18); }
  .workbook-lines span { font: 600 8pt/1 var(--font); letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
  a { color: inherit; text-decoration: none; }
  .fx-panel, .fx-illo { cursor: default; }
}
/* print-only document parts */
.page-print .cover { position: relative; height: 297mm; padding: 34mm 22mm 20mm; background: #141416; color: #F1EEE9; display: flex; flex-direction: column; break-after: page; overflow: hidden; -webkit-print-color-adjust: exact; print-color-adjust: exact; }
.cover-wave { position: absolute; left: -5%; right: -5%; top: 150mm; height: 62mm; opacity: .9; }
.cover-wave .hw1 { stroke: #C7AAFF; opacity: .4; }
.cover-wave .hw2 { stroke: #FFB04A; opacity: .9; }
.cover-brand { display: flex; align-items: center; gap: 10px; font: 700 13pt/1 var(--font-head); --accent: #FFB04A; --accent-ink: #20170D; }
.cover-brand svg { width: 26pt; height: 26pt; }
.cover-kicker { margin-top: 20mm; font: 600 10pt/1 var(--font-mono); letter-spacing: .1em; text-transform: uppercase; color: #FFB866; }
.cover-title { font: 700 34pt/1.08 var(--font-head); letter-spacing: -.02em; margin: 8mm 0 6mm; }
.cover-title span { display: block; font-size: 15pt; letter-spacing: .02em; color: #FFB866; margin-bottom: 3mm; font-family: var(--font-mono); font-weight: 600; }
.cover-sub { font-size: 13pt; color: #D5D2CC; max-width: 140mm; margin: 0; }
.cover-lessons { list-style: none; padding: 0; margin: auto 0 12mm; display: grid; gap: 4mm; font: 600 12pt/1.3 var(--font-head); }
.cover-lessons span { display: inline-block; width: 14mm; font: 600 10pt/1 var(--font-mono); color: #FFB866; }
.cover-foot { font-size: 8.5pt; color: #A3A8B2; max-width: 150mm; }
.answer-key { break-before: page; }
.answer-key h2 { font: 650 22pt/1.2 var(--font-head); }
.answer-key h3 { font: 600 13pt/1.3 var(--font-head); margin: 14pt 0 6pt; }
.answer-key p { margin: 0 0 6pt; font-size: 10pt; }
@media screen { .page-print { max-width: 820px; margin: 0 auto; padding: 20px; } .page-print .cover { height: auto; min-height: 800px; border-radius: 16px; margin-bottom: 40px; } }

/* ------------------------------------------------------------ glossary */
a.term { text-decoration: none; }
a.term:hover { text-decoration: underline; text-decoration-color: var(--accent); }
.side-glossary { display: block; margin: 18px 12px 8px; padding: 10px 12px; border-radius: 10px; border: 1px solid var(--line); color: var(--text); text-decoration: none; font-weight: 600; font-size: 14px; }
.side-glossary span { display: block; font-weight: 400; font-size: 12.5px; color: var(--muted); }
.side-glossary:hover { border-color: var(--accent); }
.glossary-letters { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 18px; }
.glossary-letters a { display: inline-grid; place-items: center; min-width: 32px; height: 32px; border-radius: 8px; background: var(--surface); border: 1px solid var(--line); color: var(--text); text-decoration: none; font-weight: 600; }
.glossary-letters a:hover { border-color: var(--accent); }
.glossary-list { margin: 0 0 28px; }
.glossary-list dt { font-family: var(--font-head); font-weight: 600; font-size: 18px; margin-top: 18px; scroll-margin-top: 80px; }
.glossary-list dt small { font-family: var(--font-body, inherit); font-weight: 400; font-size: 13px; color: var(--muted); margin-left: 6px; }
.glossary-list dd { margin: 4px 0 0; color: var(--text-soft, var(--text)); line-height: 1.6; }
.glossary-where { white-space: nowrap; font-weight: 600; font-size: 14px; }
.glossary-list dt:target { color: var(--accent-text); }
.q-verdict { font-weight: 700; }
.q-verdict.is-right { color: var(--teal); }
.q-verdict.is-wrong { color: var(--rose); }