@font-face{font-family:Archivo Variable;font-style:normal;font-display:swap;font-weight:100 900;font-stretch:62% 125%;src:url(/_astro/archivo-vietnamese-wdth-normal.rJmnGBSt.woff2)format("woff2-variations");unicode-range:U+102-103,U+110-111,U+128-129,U+168-169,U+1A0-1A1,U+1AF-1B0,U+300-301,U+303-304,U+308-309,U+323,U+329,U+1EA0-1EF9,U+20AB}@font-face{font-family:Archivo Variable;font-style:normal;font-display:swap;font-weight:100 900;font-stretch:62% 125%;src:url(/_astro/archivo-latin-ext-wdth-normal.7khWdh9v.woff2)format("woff2-variations");unicode-range:U+100-2BA,U+2BD-2C5,U+2C7-2CC,U+2CE-2D7,U+2DD-2FF,U+304,U+308,U+329,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:Archivo Variable;font-style:normal;font-display:swap;font-weight:100 900;font-stretch:62% 125%;src:url(/_astro/archivo-latin-wdth-normal.DY7AcnAa.woff2)format("woff2-variations");unicode-range:U+??,U+131,U+152-153,U+2BB-2BC,U+2C6,U+2DA,U+2DC,U+304,U+308,U+329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}@font-face{font-family:"Source Sans 3 Variable";font-style:normal;font-display:swap;font-weight:200 900;src:url(/_astro/source-sans-3-cyrillic-ext-wght-normal.DzyfIafT.woff2)format("woff2-variations");unicode-range:U+460-52F,U+1C80-1C8A,U+20B4,U+2DE0-2DFF,U+A640-A69F,U+FE2E-FE2F}@font-face{font-family:"Source Sans 3 Variable";font-style:normal;font-display:swap;font-weight:200 900;src:url(/_astro/source-sans-3-cyrillic-wght-normal.BMDVbyM7.woff2)format("woff2-variations");unicode-range:U+301,U+400-45F,U+490-491,U+4B0-4B1,U+2116}@font-face{font-family:"Source Sans 3 Variable";font-style:normal;font-display:swap;font-weight:200 900;src:url(/_astro/source-sans-3-greek-ext-wght-normal.BWSLJLk6.woff2)format("woff2-variations");unicode-range:U+1F??}@font-face{font-family:"Source Sans 3 Variable";font-style:normal;font-display:swap;font-weight:200 900;src:url(/_astro/source-sans-3-greek-wght-normal.C9H9m1vD.woff2)format("woff2-variations");unicode-range:U+370-377,U+37A-37F,U+384-38A,U+38C,U+38E-3A1,U+3A3-3FF}@font-face{font-family:"Source Sans 3 Variable";font-style:normal;font-display:swap;font-weight:200 900;src:url(/_astro/source-sans-3-vietnamese-wght-normal.C1uRvKPU.woff2)format("woff2-variations");unicode-range:U+102-103,U+110-111,U+128-129,U+168-169,U+1A0-1A1,U+1AF-1B0,U+300-301,U+303-304,U+308-309,U+323,U+329,U+1EA0-1EF9,U+20AB}@font-face{font-family:"Source Sans 3 Variable";font-style:normal;font-display:swap;font-weight:200 900;src:url(/_astro/source-sans-3-latin-ext-wght-normal.C8iNium2.woff2)format("woff2-variations");unicode-range:U+100-2BA,U+2BD-2C5,U+2C7-2CC,U+2CE-2D7,U+2DD-2FF,U+304,U+308,U+329,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:"Source Sans 3 Variable";font-style:normal;font-display:swap;font-weight:200 900;src:url(/_astro/source-sans-3-latin-wght-normal.BqRLTx4X.woff2)format("woff2-variations");unicode-range:U+??,U+131,U+152-153,U+2BB-2BC,U+2C6,U+2DA,U+2DC,U+304,U+308,U+329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}:root{--ground:#f2f4f5;--panel:#fff;--panel-2:#e8ecee;--ink:#1e2226;--ink-2:#4a545c;--steel:#5e6a73;--line:#cfd6da;--line-soft:#9aa6ad;--chalk:#2f5da8;--chalk-wash:#2f5da838;--crayon:#c43a22;--fir:#dcbf93;--fir-grain:#96683461;--waste:#f2f4f59e;--waste-line:#5e6a7359;--square:#8c979e;--square-edge:#3c454c;--ok:#2d7a4b;--warn:#a8660b;--bad:#c43a22;--ground-3d:#d9dde0;--font-display:"Archivo Variable", "Archivo", "Helvetica Neue", Arial, sans-serif;--font-body:"Source Sans 3 Variable", "Source Sans 3", "Segoe UI", system-ui, sans-serif;--r-sm:6px;--r-md:10px;--shadow:0 1px 0 #1e22260f, 0 8px 24px -16px #1e222659;--bg:var(--ground);--surface:var(--panel);--text:var(--ink);--muted:var(--ink-2);--border:var(--line);--accent:var(--chalk);--accent-text:#fff;--danger:var(--crayon);--radius:var(--r-md);color-scheme:light}@media (prefers-color-scheme:dark){:root{--ground:#15181b;--panel:#1d2226;--panel-2:#262c31;--ink:#e9edef;--ink-2:#a9b3ba;--steel:#8b979f;--line:#333b41;--line-soft:#6d7980;--chalk:#7ea4e6;--chalk-wash:#7ea4e647;--crayon:#ff7a5c;--fir:#c9a676;--fir-grain:#68462273;--waste:#15181b99;--waste-line:#a9b3ba47;--square:#9aa5ac;--square-edge:#dfe5e8;--ok:#6fcf97;--warn:#f2b35b;--bad:#ff7a5c;--ground-3d:#2a3136;--accent-text:#0d1117;--shadow:0 1px 0 #0000004d, 0 10px 28px -18px #000c;color-scheme:dark}}*{box-sizing:border-box}[hidden]{display:none!important}html{-webkit-text-size-adjust:100%;scroll-padding-top:72px}body{background:var(--ground);color:var(--ink);font:400 17px/1.55 var(--font-body);overflow-wrap:anywhere;font-feature-settings:"kern", "liga";margin:0}h1,h2,h3,h4{font-family:var(--font-display);letter-spacing:-.01em;margin:0 0 .5em;font-stretch:88%;line-height:1.12}h1{font-size:clamp(1.75rem,1.2rem + 2vw,2.75rem);font-weight:800}h2{font-size:clamp(1.35rem,1.1rem + 1vw,1.85rem);font-weight:750}h3{font-size:1.15rem;font-weight:700}p,li{max-width:72ch}a{color:var(--chalk);text-underline-offset:.18em;text-decoration-thickness:1px}a:hover{text-decoration-thickness:2px}:focus-visible{outline:3px solid var(--chalk);outline-offset:2px;border-radius:4px}img,svg,canvas{max-width:100%}.num,.readout,table{font-variant-numeric:tabular-nums}.site-header{z-index:20;background:color-mix(in srgb, var(--ground) 88%, transparent);backdrop-filter:blur(10px);border-bottom:1px solid var(--line);position:sticky;top:0}.site-header .bar{align-items:center;gap:24px;max-width:1280px;margin:0 auto;padding:10px 20px;display:flex}.brand{color:var(--ink);font:800 1.02rem/1 var(--font-display);letter-spacing:-.01em;align-items:center;gap:10px;font-stretch:85%;text-decoration:none;display:inline-flex}.brand svg{width:26px;height:26px}.nav{gap:4px;margin-left:auto;display:flex}.nav a{color:var(--ink-2);border-radius:var(--r-sm);padding:8px 12px;font-size:.95rem;font-weight:600;text-decoration:none}.nav a:hover,.nav a[aria-current=page]{color:var(--ink);background:var(--panel-2)}.nav a.cta{color:var(--accent-text);background:var(--chalk)}.nav-menu{margin-left:auto;display:none;position:relative}.nav-menu summary{cursor:pointer;border:1px solid var(--line);border-radius:var(--r-sm);background:var(--panel);align-items:center;min-height:44px;padding:8px 12px;font-weight:700;list-style:none;display:flex}.nav-menu summary::-webkit-details-marker{display:none}.nav-menu nav{background:var(--panel);border:1px solid var(--line);border-radius:var(--r-md);box-shadow:var(--shadow);min-width:230px;padding:8px;display:grid;position:absolute;top:calc(100% + 8px);right:0}.nav-menu nav a{color:var(--ink);border-radius:var(--r-sm);padding:12px;font-weight:600;text-decoration:none}.nav-menu nav a:hover{background:var(--panel-2)}@media (width<=860px){.nav{display:none}.nav-menu{display:block}}main{display:block}.wrap{max-width:1280px;margin:0 auto;padding:0 20px}.prose{max-width:760px;margin:0 auto;padding:32px 20px 24px}.prose h2{margin-top:1.8em}.prose h3{margin-top:1.4em}.prose img,.prose svg.dg{margin:12px 0;display:block}.lede{color:var(--ink-2);font-size:1.15rem}button,.button{font:700 .98rem/1 var(--font-body);border-radius:var(--r-sm);cursor:pointer;border:1px solid #0000;justify-content:center;align-items:center;gap:8px;min-height:44px;padding:12px 18px;text-decoration:none;transition:background-color .15s,border-color .15s,transform 80ms;display:inline-flex}button:active,.button:active{transform:translateY(1px)}.btn-primary{background:var(--chalk);color:var(--accent-text)}.btn-primary:hover{background:color-mix(in srgb, var(--chalk) 86%, var(--ink))}.btn-quiet{background:var(--panel);color:var(--ink);border-color:var(--line)}.btn-quiet:hover{border-color:var(--line-soft)}button:disabled{opacity:.55;cursor:not-allowed}input,select,textarea{font:600 1rem/1.2 var(--font-body);color:var(--ink);background:var(--panel);border:1px solid var(--line);border-radius:var(--r-sm);width:100%;max-width:100%;min-height:44px;padding:10px 12px}input:hover,select:hover{border-color:var(--line-soft)}input:focus,select:focus{border-color:var(--chalk);outline:2px solid var(--chalk-wash);outline-offset:0}table{border-collapse:collapse;width:100%;font-size:.95rem}th,td{text-align:left;border-bottom:1px solid var(--line);vertical-align:top;padding:9px 10px}th{font-family:var(--font-display);color:var(--ink-2);font-size:.85rem;font-weight:700;font-stretch:90%}.table-scroll{border:1px solid var(--line);border-radius:var(--r-md);background:var(--panel);overflow-x:auto}.table-scroll table th:first-child,.table-scroll table td:first-child{padding-left:14px}.dg{width:100%;height:auto;display:block}.dg text{font-family:var(--font-display);font-stretch:90%}.dg-dim{fill:var(--chalk);font-weight:650}.dg-dim.is-active{font-weight:850;text-decoration:underline}.dg-cut{fill:var(--crayon);font-weight:650}.dg-num{fill:var(--steel);font-weight:700}.dg-num.is-active{fill:var(--chalk)}.dg-square{transition:transform .55s cubic-bezier(.3,.7,.2,1)}.dg-square-body{fill:var(--square);fill-opacity:.82;stroke:var(--square-edge);stroke-width:1.3px}.dg-square-ticks{stroke:var(--square-edge);stroke-width:1px;fill:none}.dg-gauge{fill:var(--chalk)}.el-stringer{fill:var(--fir);stroke:var(--ink);stroke-width:1.8px}.el-tread{fill:color-mix(in srgb, var(--fir) 82%, var(--ink));stroke:var(--ink);stroke-width:.6px;vector-effect:non-scaling-stroke}.el-riser{fill:color-mix(in srgb, var(--fir) 70%, var(--ground));stroke:var(--ink);stroke-width:.6px;vector-effect:non-scaling-stroke}.el-deck{fill:var(--panel-2);stroke:var(--ink-2);stroke-width:1px;vector-effect:non-scaling-stroke}.el-dim{stroke:var(--chalk);stroke-width:1.3px}.el-label{fill:var(--ink-2);font-weight:600}@media (prefers-reduced-motion:reduce){.dg-square{transition:none}*{scroll-behavior:auto!important}}.site-footer{border-top:1px solid var(--line);background:var(--panel);margin-top:64px}.site-footer .cols{grid-template-columns:2fr 1fr 1fr;gap:24px;max-width:1280px;margin:0 auto;padding:32px 20px 12px;display:grid}.site-footer h3{margin-bottom:8px;font-size:.95rem}.site-footer ul{gap:6px;margin:0;padding:0;list-style:none;display:grid}.site-footer a{color:var(--ink-2);text-decoration:none}.site-footer a:hover{color:var(--ink);text-decoration:underline}.site-footer .legal{max-width:1280px;color:var(--ink-2);margin:0 auto;padding:8px 20px 28px;font-size:.9rem}.tool-legal nav{flex-wrap:wrap;gap:16px;margin:8px 0;display:flex}.tool-legal p{margin:6px 0}@media (width<=760px){.site-footer .cols{grid-template-columns:1fr}}.skip{background:var(--panel);z-index:50;padding:8px 12px;position:absolute;top:8px;left:-999px}.skip:focus{left:8px}.note{border-left:3px solid var(--line-soft);color:var(--ink-2);padding:4px 0 4px 14px}.pill{background:var(--panel-2);color:var(--ink-2);border-radius:999px;align-items:center;gap:6px;padding:4px 10px;font-size:.85rem;font-weight:650;display:inline-flex}.sr{clip:rect(0 0 0 0);white-space:nowrap;width:1px;height:1px;position:absolute;overflow:hidden}.ex-toc{flex-wrap:wrap;gap:8px;margin:12px 0;display:flex}.ex-toc a{background:var(--panel-2);color:var(--ink);border-radius:999px;padding:6px 12px;font-size:.92rem;font-weight:650;text-decoration:none}.ex-toc a:hover{background:color-mix(in srgb, var(--panel-2) 70%, var(--line-soft))}.howto-fig{background:var(--panel);border:1px solid var(--line);border-radius:var(--r-md);margin:12px 0 8px;padding:12px}.howto-fig .dg{min-width:520px}.howto-fig figcaption{color:var(--ink-2);margin-top:6px;font-size:.9rem}.drawing-scroll{-webkit-overflow-scrolling:touch;overflow-x:auto}.faq-item{border-bottom:1px solid var(--line);padding:12px 0}.faq-item summary{cursor:pointer;font:700 1.02rem/1.35 var(--font-display);font-stretch:92%}.faq-item p{color:var(--ink-2);margin:8px 0 0}.dg-halo{paint-order:stroke;stroke:var(--panel);stroke-linejoin:round;stroke-opacity:.9}.ex-fig .dg,.example-card .dg{width:100%;max-height:300px}.ex-board .dg{max-height:360px}.tool-account,.tool-unlock,.legal-page{max-width:760px;margin:0 auto;padding:32px 20px}.tool-account form{gap:10px;max-width:420px;display:grid}