@font-face{font-family:Titillium Web;font-style:normal;font-weight:400;font-display:swap;src:url(/_next/static/media/81f2f04080433cef-s.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-20c4,u+2113,u+2c60-2c7f,u+a720-a7ff}@font-face{font-family:Titillium Web;font-style:normal;font-weight:400;font-display:swap;src:url(/_next/static/media/ed9cb87f7cefa820-s.p.woff2) format("woff2");unicode-range:u+00??,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:Titillium Web;font-style:normal;font-weight:600;font-display:swap;src:url(/_next/static/media/ef9d7e3625c86286-s.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-20c4,u+2113,u+2c60-2c7f,u+a720-a7ff}@font-face{font-family:Titillium Web;font-style:normal;font-weight:600;font-display:swap;src:url(/_next/static/media/c95d4fce0b415528-s.p.woff2) format("woff2");unicode-range:u+00??,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:Titillium Web;font-style:normal;font-weight:700;font-display:swap;src:url(/_next/static/media/e3bec91e60544e8d-s.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-20c4,u+2113,u+2c60-2c7f,u+a720-a7ff}@font-face{font-family:Titillium Web;font-style:normal;font-weight:700;font-display:swap;src:url(/_next/static/media/56b5d6ac638045ae-s.p.woff2) format("woff2");unicode-range:u+00??,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:Titillium Web Fallback;src:local("Arial");ascent-override:119.97%;descent-override:41.09%;line-gap-override:0.00%;size-adjust:94.44%}.__className_2a6cd1{font-family:Titillium Web,Titillium Web Fallback;font-style:normal}.__variable_2a6cd1{--font-display:"Titillium Web","Titillium Web Fallback"}@font-face{font-family:Source Sans\ 3;font-style:normal;font-weight:200 900;font-display:swap;src:url(/_next/static/media/084282eba306c257-s.woff2) format("woff2");unicode-range:u+0460-052f,u+1c80-1c8a,u+20b4,u+2de0-2dff,u+a640-a69f,u+fe2e-fe2f}@font-face{font-family:Source Sans\ 3;font-style:normal;font-weight:200 900;font-display:swap;src:url(/_next/static/media/1e377d93cbdd6b44-s.woff2) format("woff2");unicode-range:u+0301,u+0400-045f,u+0490-0491,u+04b0-04b1,u+2116}@font-face{font-family:Source Sans\ 3;font-style:normal;font-weight:200 900;font-display:swap;src:url(/_next/static/media/ec1d0aa2d2fbc083-s.woff2) format("woff2");unicode-range:u+1f??}@font-face{font-family:Source Sans\ 3;font-style:normal;font-weight:200 900;font-display:swap;src:url(/_next/static/media/f1dd23950e6cd390-s.woff2) format("woff2");unicode-range:u+0370-0377,u+037a-037f,u+0384-038a,u+038c,u+038e-03a1,u+03a3-03ff}@font-face{font-family:Source Sans\ 3;font-style:normal;font-weight:200 900;font-display:swap;src:url(/_next/static/media/0c7826ffb3acea36-s.woff2) format("woff2");unicode-range:u+0102-0103,u+0110-0111,u+0128-0129,u+0168-0169,u+01a0-01a1,u+01af-01b0,u+0300-0301,u+0303-0304,u+0308-0309,u+0323,u+0329,u+1ea0-1ef9,u+20ab}@font-face{font-family:Source Sans\ 3;font-style:normal;font-weight:200 900;font-display:swap;src:url(/_next/static/media/b6a6f0b43d027304-s.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-20c4,u+2113,u+2c60-2c7f,u+a720-a7ff}@font-face{font-family:Source Sans\ 3;font-style:normal;font-weight:200 900;font-display:swap;src:url(/_next/static/media/692df4da22e71021-s.p.woff2) format("woff2");unicode-range:u+00??,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:Source Sans\ 3 Fallback;src:local("Arial");ascent-override:109.21%;descent-override:42.66%;line-gap-override:0.00%;size-adjust:93.76%}.__className_bea9d5{font-family:Source Sans\ 3,Source Sans\ 3 Fallback;font-style:normal}.__variable_bea9d5{--font-text:"Source Sans 3","Source Sans 3 Fallback"}:root{--teal:#0699a6;--teal-ink:#05707a;--teal-wash:#e9f5f6;--ink:#0d1b1e;--ink-2:#44565a;--ink-3:#6c7d81;--line:#dce4e5;--surface:#f4f7f7;--bg:#ffffff;--topbar-h:4.25rem;--index-w:19.5rem;--font-display:"Titillium Web",system-ui,sans-serif;--font-text:"Source Sans 3",system-ui,-apple-system,"Segoe UI",sans-serif;color-scheme:light}*{box-sizing:border-box}html{-webkit-text-size-adjust:100%;scroll-padding-top:var(--topbar-h)}body{margin:0;background:var(--bg);color:var(--ink);font:400 1.0625rem/1.65 var(--font-text);-webkit-font-smoothing:antialiased}a,button{color:inherit}button{font:inherit}:focus-visible{outline:2px solid var(--teal);outline-offset:2px;border-radius:2px}.course{display:grid;grid-template-columns:var(--index-w) minmax(0,1fr);min-height:100dvh}.topbar{grid-column:1/-1;position:-webkit-sticky;position:sticky;top:0;z-index:20;display:flex;align-items:center;gap:1.25rem;height:var(--topbar-h);padding:0 1.75rem;background:var(--bg);border-bottom:1px solid var(--line)}.brand{display:block;flex:none}.brand-crop{position:relative;display:block;height:2.5rem;aspect-ratio:1849/536;overflow:hidden}.brand-crop img{position:absolute;left:-4.11%;top:-43.28%;width:108.17%;height:auto;max-width:none}.topbar-title{padding-left:1.25rem;border-left:1px solid var(--line);font:600 1rem/1.2 var(--font-display);letter-spacing:.01em}.meter{margin-left:auto;display:flex;align-items:center;gap:.75rem}.meter-text{font-size:.875rem;color:var(--ink-3);font-feature-settings:"tnum";font-variant-numeric:tabular-nums;white-space:nowrap}.meter-text strong{color:var(--ink);font-weight:600}.meter-bar{width:7.5rem;height:4px;background:var(--line);border-radius:2px;overflow:hidden}.meter-bar span{display:block;height:100%;background:var(--teal);transition:width .3s ease}.index-toggle{display:none;align-items:center;gap:.4rem;padding:.45rem .75rem;background:none;border:1px solid var(--line);border-radius:4px;font-size:.9375rem;font-weight:600;cursor:pointer}.index-toggle svg{width:.75rem;height:.75rem;fill:none;stroke:currentColor;stroke-width:1.5;transition:transform .2s}.index-toggle[aria-expanded=true] svg{transform:rotate(180deg)}.index{position:-webkit-sticky;position:sticky;top:var(--topbar-h);align-self:start;height:calc(100dvh - var(--topbar-h));overflow-y:auto;padding:2.25rem 0 2rem;background:var(--surface);border-right:1px solid var(--line)}.index-heading{margin:0 0 .75rem;padding:0 1.75rem;font-size:.75rem;font-weight:600;letter-spacing:.1em;text-transform:uppercase;color:var(--ink-3)}.index ol{list-style:none;margin:0;padding:0}.index a{display:grid;grid-template-columns:1.75rem minmax(0,1fr) 1rem;align-items:baseline;grid-gap:.5rem;gap:.5rem;padding:.6rem 1.25rem .6rem 1.75rem;border-left:3px solid transparent;font-size:.9688rem;line-height:1.35;color:var(--ink-2);text-decoration:none}.index a:hover{color:var(--ink);background:rgba(13,27,30,.035)}.index a[aria-current=page]{border-left-color:var(--teal);background:var(--bg);color:var(--ink);font-weight:600}.index-marker{font:600 .8125rem/1.35 var(--font-display);letter-spacing:.02em;color:var(--ink-3);font-feature-settings:"tnum";font-variant-numeric:tabular-nums}.index-marker:empty:before{content:"";display:inline-block;width:.7rem;height:1px;background:currentColor;vertical-align:middle}.index a[aria-current=page] .index-marker{color:var(--teal-ink)}.index-check{width:1rem;height:1rem;align-self:center;fill:none;stroke:var(--teal);stroke-width:1.75;stroke-linecap:round;stroke-linejoin:round}.lesson{display:flex;flex-direction:column;min-height:calc(100dvh - var(--topbar-h));padding:4rem clamp(1.5rem,6vw,6rem) 0}.lesson>*{width:100%;max-width:46rem}.lesson-body{flex:1 1}.lesson-header{margin-bottom:2.25rem;padding-bottom:1.75rem;border-bottom:1px solid var(--line)}.eyebrow{margin:0 0 .75rem;font-size:.8125rem;font-weight:600;letter-spacing:.1em;text-transform:uppercase;color:var(--teal-ink)}h1{margin:0;font:600 clamp(2rem,1.4rem + 2vw,2.75rem) /1.12 var(--font-display);letter-spacing:-.012em;text-wrap:balance}.lesson-header-cover h1{font-size:clamp(2.25rem,1.4rem + 3vw,3.5rem);line-height:1.06;max-width:14em}.cover-welcome{margin:0 0 .75rem;font:600 1.375rem/1.3 var(--font-display)}.lesson-body p{margin:0 0 1.25rem;max-width:40rem;color:var(--ink-2)}.lesson-body p.lead{font-size:1.25rem;line-height:1.55;color:var(--ink)}.lesson-body strong{color:var(--ink);font-weight:600}.steps{list-style:none;counter-reset:step;margin:2rem 0;padding:0;border-bottom:1px solid var(--line)}.steps li{counter-increment:step;display:grid;grid-template-columns:3.25rem minmax(0,1fr);align-items:baseline;padding:1rem 0;border-top:1px solid var(--line);font-size:1.125rem;line-height:1.5}.steps li:before{content:counter(step);font:600 1.5rem/1 var(--font-display);color:var(--teal-ink);font-feature-settings:"tnum";font-variant-numeric:tabular-nums}.options{list-style:none;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));grid-gap:0;gap:0;margin:0 0 1.75rem;padding:0;border:1px solid var(--line);border-radius:6px}.options li{padding:1.1rem 1.25rem;color:var(--ink-2);line-height:1.5}.options li+li{border-left:1px solid var(--line)}.options strong{display:block;margin-bottom:.2rem;font:600 1.0625rem/1.3 var(--font-display)}.note{margin:2rem 0;padding:1.1rem 1.4rem 1.2rem;background:var(--teal-wash);border-left:3px solid var(--teal);border-radius:0 6px 6px 0}.note-label{display:block;margin-bottom:.3rem;font-size:.75rem;font-weight:600;letter-spacing:.1em;text-transform:uppercase;color:var(--teal-ink)}.lesson-body .note p{margin:0;color:var(--ink)}.media{margin:2rem 0}.media img,.media video{display:block;width:100%;height:auto;border-radius:6px;border:1px solid var(--line);background:var(--surface)}.fig figcaption,.media figcaption{margin-top:.6rem;font-size:.9375rem;line-height:1.45;color:var(--ink-3)}.media-pair{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));grid-gap:1.25rem;gap:1.25rem;margin:2rem 0;align-items:start}.media-pair .media,.media-pair .player{margin:0}.media-frame{position:relative;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:.2rem;aspect-ratio:16/9;padding:1.25rem;text-align:center;background:var(--surface);border:1px dashed #b9c6c8;border-radius:6px}.media-frame svg{width:2.5rem;height:2.5rem;margin-bottom:.6rem;fill:none;stroke:var(--teal);stroke-width:1.5;stroke-linejoin:round}.media-kind{font-size:.75rem;font-weight:600;letter-spacing:.1em;text-transform:uppercase;color:var(--teal-ink)}.media-label{font:600 1.0625rem/1.3 var(--font-display);color:var(--ink);text-wrap:balance}.media-status{font-size:.875rem;color:var(--ink-3)}.media-hint{position:absolute;left:.6rem;bottom:.5rem;font:.6875rem/1 ui-monospace,SFMono-Regular,Menlo,monospace;color:var(--ink-3)}.player{margin:2rem 0}.player-screen{position:relative;overflow:hidden;background:var(--ink);border-radius:6px}.player-screen video{display:block;width:100%;height:100%;object-fit:contain;cursor:pointer}.player figcaption{margin-top:.5rem;font-size:.9375rem;line-height:1.45;color:var(--ink-3)}.player-overlay{position:absolute;inset:0;display:grid;place-items:center;padding:0;background:rgba(13,27,30,.28);border:0;cursor:pointer}.player-overlay span{display:grid;place-items:center;width:4rem;height:4rem;background:#fff;color:var(--ink);border-radius:50%;box-shadow:0 6px 20px rgba(13,27,30,.3);transition:transform .15s,color .15s}.player-overlay:hover span{transform:scale(1.06);color:var(--teal-ink)}.player-overlay svg{width:1.5rem;height:1.5rem}.player svg{fill:none;stroke:currentColor;stroke-width:1.5;stroke-linecap:round;stroke-linejoin:round}.player-controls{display:flex;align-items:center;gap:.5rem;margin-top:.75rem}.player-controls button{flex:none;display:grid;place-items:center;width:2.25rem;height:2.25rem;padding:0;background:var(--bg);border:1px solid var(--line);border-radius:4px;cursor:pointer}.player-controls button:first-child{background:var(--ink);border-color:var(--ink);color:#fff}.player-controls button:hover:not(:disabled){border-color:var(--teal-ink);color:var(--teal-ink)}.player-controls button:first-child:hover{background:var(--teal-ink);color:#fff}.player-controls button:disabled{color:#b9c6c8;cursor:default}.player-controls svg{width:1rem;height:1rem}.player-time{flex:none;font-size:.8125rem;color:var(--ink-3);font-feature-settings:"tnum";font-variant-numeric:tabular-nums;white-space:nowrap}.player-controls input[type=range]{flex:1 1;min-width:0;height:1.25rem;margin:0 .25rem;background:none;-moz-appearance:none;appearance:none;-webkit-appearance:none;cursor:pointer}.player-controls input[type=range]::-webkit-slider-runnable-track{height:4px;border-radius:2px;background:linear-gradient(90deg,var(--teal) var(--played,0),var(--line) var(--played,0))}.player-controls input[type=range]::-moz-range-track{height:4px;border-radius:2px;background:var(--line)}.player-controls input[type=range]::-moz-range-progress{height:4px;border-radius:2px;background:var(--teal)}.player-controls input[type=range]::-webkit-slider-thumb{-webkit-appearance:none;width:12px;height:12px;margin-top:-4px;border-radius:50%;background:var(--teal-ink);border:0}.player-controls input[type=range]::-moz-range-thumb{width:12px;height:12px;border-radius:50%;background:var(--teal-ink);border:0}.player[data-device=phone]{width:100%;max-width:17rem;margin-left:auto;margin-right:auto}.player[data-device=phone] .player-screen{margin:7px;border-radius:2.1rem;box-shadow:0 0 0 7px var(--ink),0 0 0 8px #3a4a4e,0 18px 36px -18px rgba(13,27,30,.45)}.demo{display:grid;grid-template-columns:17rem minmax(0,1fr);grid-gap:2.75rem;gap:2.75rem;align-items:start;margin:2rem 0}.demo .player,.demo .steps{margin-top:0;margin-bottom:0}.fig{margin:2rem 0}.fig-ratio{display:grid;grid-template-columns:minmax(0,1fr) auto minmax(0,1fr);align-items:stretch;border:1px solid var(--line);border-radius:6px;overflow:hidden}.fig-term{display:flex;flex-direction:column;gap:.35rem;padding:1.4rem 1.6rem 1.5rem}.fig-term-result{background:var(--teal-wash)}.fig-key{font-size:.75rem;font-weight:600;letter-spacing:.1em;text-transform:uppercase;color:var(--ink-3)}.fig-value{font:600 clamp(2rem,1.2rem + 3vw,3rem) /1 var(--font-display);letter-spacing:-.015em;font-feature-settings:"tnum";font-variant-numeric:tabular-nums;white-space:nowrap}.fig-term-result .fig-key,.fig-term-result .fig-value{color:var(--teal-ink)}.fig-rate{display:flex;align-items:center;padding:0 1.1rem;border-left:1px solid var(--line);border-right:1px solid var(--line);background:var(--surface)}.fig-rate span{font:600 1.125rem/1 var(--font-display);color:var(--ink-2);white-space:nowrap}.fig-rate span:before{content:"× ";color:var(--ink-3);font-weight:400}.fig-bar{height:6px;margin-top:.75rem;background:var(--line);border-radius:3px;overflow:hidden;display:flex;justify-content:flex-end}.fig-bar span{display:block;background:var(--teal)}.fig-timeline{padding:1.6rem 1.6rem 1.4rem;border:1px solid var(--line);border-radius:6px}.fig-track{position:relative;height:6px;margin:0 .3rem 1rem;background:var(--teal-wash);border-radius:3px}.fig-track span{position:absolute;inset:0;background:linear-gradient(90deg,var(--teal),var(--teal));border-radius:3px}.fig-track:after,.fig-track:before{content:"";position:absolute;top:50%;width:14px;height:14px;margin-top:-7px;border-radius:50%;background:var(--bg);border:3px solid var(--teal);z-index:1}.fig-track:before{left:-4px}.fig-track:after{right:-4px}.fig-timeline ol{list-style:none;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));grid-gap:.75rem;gap:.75rem;margin:0;padding:0;font-size:.9375rem;line-height:1.4;color:var(--ink-2)}.fig-timeline li:nth-child(2){text-align:center}.fig-timeline li:nth-child(3){text-align:right}.fig-timeline strong{display:block;font:600 1.125rem/1.3 var(--font-display)}.fig-timeline li:nth-child(2) strong{color:var(--teal-ink)}.lesson-footer{display:flex;align-items:center;justify-content:space-between;gap:1.5rem;margin-top:3rem;padding-top:1.75rem;border-top:1px solid var(--line)}.lesson-previous{display:flex;flex-direction:column;font-weight:600;line-height:1.35;text-decoration:none}.lesson-previous span{font-size:.8125rem;font-weight:400;color:var(--ink-3)}.lesson-previous:hover{color:var(--teal-ink)}.button{display:inline-flex;align-items:center;gap:1.1rem;padding:.8rem 1.25rem .8rem 1.4rem;background:var(--ink);color:#fff;border:1px solid var(--ink);border-radius:6px;text-align:left;text-decoration:none;cursor:pointer;transition:background .15s,border-color .15s}.button:hover{background:var(--teal-ink);border-color:var(--teal-ink)}.button-text{display:flex;flex-direction:column;font-weight:600;line-height:1.3}.button-text small{font-size:.8125rem;font-weight:400;opacity:.72}.button svg{flex:none;width:1rem;height:1rem;fill:none;stroke:currentColor;stroke-width:1.5;stroke-linecap:round;stroke-linejoin:round}.button-quiet{background:var(--bg);color:var(--ink);border-color:var(--ink);font-weight:600}.button-quiet:hover{background:var(--ink);border-color:var(--ink);color:#fff}.link-button{padding:0;background:none;border:0;color:var(--ink-3);text-decoration:underline;text-underline-offset:3px;cursor:pointer}.link-button:hover{color:var(--ink)}.lesson-finish{display:flex;flex-direction:column;align-items:flex-end;gap:.5rem}.lesson-finish small{font-size:.875rem;color:var(--ink-3)}.lesson-end{margin-top:3rem;padding:1.75rem 1.75rem 1.9rem;background:var(--teal-wash);border-top:3px solid var(--teal);border-radius:0 0 6px 6px}.lesson-end p{margin:0 0 1.25rem;color:var(--ink-2)}.lesson-end .lesson-end-title{margin-bottom:.3rem;font:600 1.5rem/1.25 var(--font-display);color:var(--ink)}.lesson-end-actions{flex-wrap:wrap;gap:1.25rem}.credits,.lesson-end-actions{display:flex;align-items:center}.credits{gap:.75rem;margin-top:4.5rem;padding:1.5rem 0 2rem;border-top:1px solid var(--line);font-size:.8125rem;color:var(--ink-3)}.credits img{width:auto;height:1.75rem}.credits-version{margin-left:auto;font-feature-settings:"tnum";font-variant-numeric:tabular-nums}@media (max-width:60rem){.course{grid-template-columns:minmax(0,1fr)}.topbar{gap:.9rem;padding:0 1rem}.meter-text,.topbar-title{display:none}.meter-bar{width:4.5rem}.brand-crop{height:2.125rem}.index-toggle{display:inline-flex}.index{position:fixed;inset:var(--topbar-h) 0 auto 0;z-index:15;height:auto;max-height:calc(100dvh - var(--topbar-h));padding:1.25rem 0 1rem;border-right:0;border-bottom:1px solid var(--line);box-shadow:0 16px 32px -16px rgba(13,27,30,.25)}.index[data-open=false]{display:none}.index a,.index-heading{padding-left:1rem;padding-right:1rem}.lesson{padding:2.25rem 1rem 0}.lesson-header{margin-bottom:1.75rem;padding-bottom:1.25rem}.lesson-body p.lead{font-size:1.1875rem}}@media (max-width:46rem){.demo{grid-template-columns:minmax(0,1fr);gap:2rem}.player[data-device=phone]{max-width:16rem}}@media (max-width:36rem){.media-pair,.options{grid-template-columns:minmax(0,1fr)}.options li+li{border-left:0;border-top:1px solid var(--line)}.steps li{grid-template-columns:2.5rem minmax(0,1fr);font-size:1.0625rem}.fig-ratio{grid-template-columns:minmax(0,1fr)}.fig-term{padding:1.1rem 1.25rem 1.2rem}.fig-rate{padding:.55rem 1.25rem;border:0;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}.fig-timeline{padding:1.25rem 1rem 1.1rem}.fig-timeline ol{font-size:.8125rem}.fig-timeline strong{font-size:1rem}.lesson-footer{flex-direction:column-reverse;align-items:stretch}.lesson-footer .button{justify-content:space-between}.lesson-finish{align-items:stretch}.credits{flex-wrap:wrap}}@media (prefers-reduced-motion:reduce){*{transition:none!important}}