/* Shared appearance only. Learning geometry and pixel data are not inverted. */
:root{color-scheme:light;--paper:#ffffff;--ink:#1b1c1e;--quiet:#5f6268;--line:#d1d5db;--wash:#f0f2f4;--lab-surface:#f5f6f7;--control-border:#777f88;--diagram-guide:#79818a;--diagram-axis:#727a84;--diagram-flow:#727982;--diagram-angle:#626b76;--diagram-muted:#727982;--grid:#d1d5db;--figure-subtle:#e1e5e9;--shadow-color:#0000001a;--accent:#9b442f;--accent-text:#8f3d2a;--mesh-fill:#e1ded5;--mesh-line:#77756f;--mesh-ground:#f0efea;--penalty-muted:#626b76;--bg:var(--paper);--fg:var(--ink);--muted:var(--quiet);--strong:var(--ink);}
:root[data-theme="dark"]{color-scheme:dark;--paper:#111315;--ink:#ebedef;--quiet:#b4b9c1;--line:#343d46;--wash:#22282e;--lab-surface:#191d21;--control-border:#88939f;--diagram-guide:#96a1ad;--diagram-axis:#a4aeba;--diagram-flow:#a4aeba;--diagram-angle:#b1bac5;--diagram-muted:#a4aeba;--grid:#38414a;--figure-subtle:#3d4650;--shadow-color:#00000066;--accent:#e6a18b;--accent-text:#edb4a1;--mesh-fill:#283139;--mesh-line:#85939e;--mesh-ground:#1a2026;--penalty-muted:#afb9c4;--bg:var(--paper);--fg:var(--ink);--muted:var(--quiet);--strong:var(--ink);}
@media(prefers-color-scheme:dark){:root:not([data-theme]){color-scheme:dark;--paper:#111315;--ink:#ebedef;--quiet:#b4b9c1;--line:#343d46;--wash:#22282e;--lab-surface:#191d21;--control-border:#88939f;--diagram-guide:#96a1ad;--diagram-axis:#a4aeba;--diagram-flow:#a4aeba;--diagram-angle:#b1bac5;--diagram-muted:#a4aeba;--grid:#38414a;--figure-subtle:#3d4650;--shadow-color:#00000066;--accent:#e6a18b;--accent-text:#edb4a1;--mesh-fill:#283139;--mesh-line:#85939e;--mesh-ground:#1a2026;--penalty-muted:#afb9c4;--bg:var(--paper);--fg:var(--ink);--muted:var(--quiet);--strong:var(--ink);}}
.print-edition{color-scheme:light;--paper:#ffffff;--ink:#1b1c1e;--quiet:#5f6268;--line:#d1d5db;--wash:#f0f2f4;--lab-surface:#f5f6f7;--control-border:#777f88;--diagram-guide:#79818a;--diagram-axis:#727a84;--diagram-flow:#727982;--diagram-angle:#626b76;--diagram-muted:#727982;--grid:#d1d5db;--figure-subtle:#e1e5e9;--shadow-color:#0000001a;--accent:#9b442f;--accent-text:#8f3d2a;--mesh-fill:#e1ded5;--mesh-line:#77756f;--mesh-ground:#f0efea;--penalty-muted:#626b76;--bg:var(--paper);--fg:var(--ink);--muted:var(--quiet);--strong:var(--ink);}
html{background:var(--paper)}
body{background:var(--paper);color:var(--ink)}
::selection{background:var(--ink);color:var(--paper)}
button,select{border-color:var(--control-border)}
button:hover,select:hover{background:var(--wash)}
button.primary:hover{background:var(--ink);color:var(--paper);text-decoration:underline}
.theme-toggle{display:inline-flex;align-items:center;justify-content:center;gap:7px;min-height:40px;flex:none;margin:0;padding:8px 11px;border:1px solid var(--control-border);border-radius:2px;background:var(--paper);color:var(--ink);font:12px/1 Arial,Helvetica,sans-serif;cursor:pointer}
.theme-toggle[hidden]{display:none!important}
.theme-toggle .theme-icon{display:none;width:18px;height:20px;font:20px/1 Arial,Helvetica,sans-serif;text-align:center}
:root[data-theme="light"] .theme-dark-icon,:root[data-theme="dark"] .theme-light-icon{display:block}
.theme-toggle:focus-visible{outline:3px solid var(--ink);outline-offset:4px}
.theme-toggle:active{transform:none}
.header-right,.header-links{gap:14px}
.book-menu nav{box-shadow:0 12px 30px var(--shadow-color)}
.article blockquote{border-left-color:var(--control-border)}
.article .lab{background:var(--lab-surface)}
.diagram .guide{stroke:var(--diagram-guide)}
.diagram .axis{stroke:var(--diagram-axis)}
.diagram .flow,.diagram .arrowhead{stroke:var(--diagram-flow)}
.diagram .angle{stroke:var(--diagram-angle)}
.diagram .grid{stroke:var(--grid)}
.unit-plot>circle[fill="none"]{stroke:var(--diagram-guide)}
@media(max-width:650px){.header-right,.header-links{gap:8px}.theme-toggle{width:38px;min-height:38px;padding:8px}.theme-toggle .theme-label{display:none}.site-header .brand>span:not(.brand-mark){display:none}}
@media(max-width:350px){.site-header{padding-left:14px;padding-right:14px}.site-header .brand{font-size:20px}.site-header .brand-mark{display:none}}
@media(forced-colors:active){:root,:root[data-theme],.print-edition{--paper:Canvas;--ink:CanvasText;--quiet:CanvasText;--line:GrayText;--wash:Canvas;--lab-surface:Canvas;--control-border:ButtonText;--diagram-guide:CanvasText;--diagram-axis:CanvasText;--diagram-flow:CanvasText;--diagram-angle:CanvasText;--diagram-muted:CanvasText;--grid:GrayText;--figure-subtle:Canvas;--accent:Highlight;--accent-text:CanvasText;--mesh-fill:Canvas;--mesh-line:CanvasText;--mesh-ground:Canvas;--penalty-muted:CanvasText;--bg:Canvas;--fg:CanvasText;--muted:CanvasText;--strong:CanvasText}.theme-toggle{border-color:ButtonText}}
@media print{:root,:root[data-theme],.print-edition{color-scheme:light;--paper:#ffffff;--ink:#1b1c1e;--quiet:#5f6268;--line:#d1d5db;--wash:#f0f2f4;--lab-surface:#f5f6f7;--control-border:#777f88;--diagram-guide:#79818a;--diagram-axis:#727a84;--diagram-flow:#727982;--diagram-angle:#626b76;--diagram-muted:#727982;--grid:#d1d5db;--figure-subtle:#e1e5e9;--shadow-color:#0000001a;--accent:#9b442f;--accent-text:#8f3d2a;--mesh-fill:#e1ded5;--mesh-line:#77756f;--mesh-ground:#f0efea;--penalty-muted:#626b76;--bg:var(--paper);--fg:var(--ink);--muted:var(--quiet);--strong:var(--ink);}html,body{background:#fff;color:#1b1c1e}.theme-toggle{display:none!important}}