.web-apps-scratch{box-sizing:border-box;margin:0;padding:clamp(16px,3vh,32px) 0;width:100%;max-width:100%;--scratch-card-max: 560px;background:transparent;font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace}@media(min-width:1024px){html.continuous-chapters .kelvin-scratch{--scratch-card-max: 380px}}.web-apps-scratch__stage{position:relative;display:flex;flex-wrap:wrap;align-items:flex-end;justify-content:flex-start;gap:clamp(16px,3vw,28px);width:100%;max-width:100%;margin:0;overflow:visible}.web-apps-scratch__card-wrap{position:relative;width:min(100%,var(--scratch-card-max),72dvh);max-width:100%;flex:0 0 auto}.web-apps-scratch__card-wrap--hover,.web-apps-scratch__card-wrap--active{cursor:none}.web-apps-scratch__card{position:relative;width:100%;max-height:min(var(--scratch-card-max),72dvh);aspect-ratio:1;height:auto;border:1px solid #d4d2cb;border-radius:8px;background:#fafaf8;box-shadow:0 8px 40px #0000001f;overflow:hidden}.web-apps-scratch__scratch-canvas{display:block;cursor:none!important}.web-apps-scratch__placeholder{width:100%;height:100%;background:linear-gradient(135deg,#c9c7c1,#e8e6e0)}.kelvin-after-wireframe{display:block}.web-apps-scratch__card-idle{position:relative;width:100%;height:100%}.web-apps-scratch__card-cover{position:absolute;inset:0;width:100%;height:100%;display:block;-o-object-fit:fill;object-fit:fill;pointer-events:none}.web-apps-scratch__card-hint{position:absolute;left:50%;bottom:12%;transform:translate(-50%);margin:0;padding:8px 12px;max-width:85%;font-size:10px;letter-spacing:.06em;text-transform:uppercase;text-align:center;line-height:1.45;color:#ffffffeb;background:#00000073;border-radius:4px;pointer-events:none}.web-apps-scratch__coin-cursor{position:absolute;width:var(--scratch-coin-size, 64px);height:var(--scratch-coin-size, 64px);transform:translate(-50%,-50%);pointer-events:none;z-index:30;-o-object-fit:contain;object-fit:contain;border-radius:50%;filter:drop-shadow(0 4px 10px rgba(0,0,0,.35))}.web-apps-scratch__tray{container-type:inline-size;container-name:scratch-tray;flex:0 0 auto;display:flex;align-items:center;justify-content:center;min-width:0;width:100%;max-width:var(--scratch-tray-max, 280px)}.web-apps-scratch__tray-bar{display:grid;grid-template-columns:minmax(0,1fr) auto minmax(0,1fr);grid-template-areas:"take coin leave";align-items:center;gap:clamp(10px,3vw,24px);box-sizing:border-box;width:100%;margin:0;padding:clamp(14px,3vh,20px) clamp(12px,3vw,20px);border:none;border-radius:12px;background:transparent;cursor:pointer;font:inherit;text-align:inherit;transition:background .16s ease}@container scratch-tray (max-width: 400px){.web-apps-scratch__tray-bar:not(.kelvin-scratch__tray-bar){display:flex;flex-direction:column;align-items:center;gap:12px;padding-block:16px}.web-apps-scratch__tray-bar:not(.kelvin-scratch__tray-bar) .web-apps-scratch__tray-phrase-wrap--take,.web-apps-scratch__tray-bar:not(.kelvin-scratch__tray-bar) .web-apps-scratch__tray-phrase-wrap--leave{width:100%;justify-content:center}.web-apps-scratch__tray-bar:not(.kelvin-scratch__tray-bar) .web-apps-scratch__tray-phrase--take,.web-apps-scratch__tray-bar:not(.kelvin-scratch__tray-bar) .web-apps-scratch__tray-phrase--leave{text-align:center}}.web-apps-scratch__tray-phrase-wrap{display:flex;min-width:0;align-self:center}.web-apps-scratch__tray-phrase-wrap--take{grid-area:take;justify-content:flex-end}.web-apps-scratch__tray-phrase-wrap--leave{grid-area:leave;justify-content:flex-start}.web-apps-scratch__tray-bar--drop{background:var(--color-nav-pill-muted-accent-1)}.web-apps-scratch__tray-bar--drop:hover{background:color-mix(in srgb,var(--color-accent, #de3e18) 16%,var(--color-nav-pill-muted-accent-1))}.web-apps-scratch__tray-bar:focus{outline:none}.web-apps-scratch__tray-bar:focus-visible{outline:2px solid var(--color-accent, #de3e18);outline-offset:3px}.web-apps-scratch__tray-phrase{pointer-events:none;font-family:var(--font-mono);font-size:clamp(10px,2.1vw,12px);font-weight:700;letter-spacing:.1em;line-height:1.35;text-transform:uppercase;color:var(--color-nav-faded-selection);transition:color .16s ease}.web-apps-scratch__tray-phrase--take{text-align:right}.web-apps-scratch__tray-phrase--leave{text-align:left}.web-apps-scratch__tray-bar--ready .web-apps-scratch__tray-phrase--take,.web-apps-scratch__tray-bar--drop .web-apps-scratch__tray-phrase--leave{opacity:1;color:var(--color-accent, #de3e18)}.web-apps-scratch__tray-coin{grid-area:coin;position:relative;box-sizing:border-box;pointer-events:none;flex:0 0 auto;width:var(--scratch-coin-size, 64px);height:var(--scratch-coin-size, 64px);display:flex;align-items:center;justify-content:center;border-radius:50%;overflow:hidden;background:transparent}.web-apps-scratch__tray-coin--empty .web-apps-scratch__tray-coin-slot{background:color-mix(in srgb,var(--color-accent, #de3e18) 32%,transparent)}.web-apps-scratch__tray-coin-slot{display:block;width:42%;height:42%;border-radius:50%;background:color-mix(in srgb,var(--color-accent, #de3e18) 28%,transparent)}.web-apps-scratch__tray-coin-img{display:block;width:100%;height:100%;-o-object-fit:contain;object-fit:contain;filter:drop-shadow(0 4px 10px rgba(0,0,0,.35));pointer-events:none;transform:scale(.78);transition:transform .16s ease}.web-apps-scratch__tray-bar--ready:hover .web-apps-scratch__tray-coin-img,.web-apps-scratch__tray-bar--ready:focus-visible .web-apps-scratch__tray-coin-img{transform:scale(.9)}@media(prefers-reduced-motion:reduce){.web-apps-scratch__tray-coin-img{transition:none}}.web-apps-scratch__footer{display:flex;flex-wrap:wrap;align-items:center;gap:16px 24px;margin-top:16px;width:100%;max-width:min(var(--scratch-card-max),100%)}.web-apps-scratch__count{margin:0;font-size:12px;color:#4a4a4a}.web-apps-scratch__reset{margin-left:auto;padding:8px 16px;font-family:inherit;font-size:11px;font-weight:600;letter-spacing:.06em;text-transform:uppercase;color:#f5431b;background:transparent;border:1px solid #f5431b;border-radius:4px;cursor:pointer}.web-apps-scratch__reset:hover{background:#f5431b14}.web-apps-scratch__reset:focus-visible{outline:2px solid #f5431b;outline-offset:2px}@media(max-width:620px){.web-apps-scratch__stage:not(.kelvin-scratch__stage){flex-direction:column;align-items:flex-start}.web-apps-scratch__card-wrap{width:min(100%,62dvh)}.web-apps-scratch__card{max-height:min(var(--scratch-card-max),62dvh)}}.web-apps-chapter-slot .chapter-slide__stage{min-height:min(480px,52dvh)}.kelvin-scratch.web-apps-scratch{padding-block:clamp(8px,1.5vh,20px) 0}.kelvin-scratch{display:flex;flex-direction:column;align-items:center;pointer-events:auto;container-type:inline-size;container-name:kelvin-scratch-root;--scratch-ticket-scale: 1;--scratch-ticket-aspect: calc(1274.34 / 805.73);--scratch-ticket-h-max: min(44dvh, 500px, calc(100dvh - 12rem) );--scratch-ticket-w-from-h: calc(var(--scratch-ticket-h-max) * .6323);--scratch-ticket-w-max: min( clamp(var(--cs-stage-min, 220px), 28vw, var(--cs-stage-max, 560px)), var(--scratch-ticket-w-from-h) );margin:0 0 28px;padding:0;width:var(--scratch-ticket-w, var(--scratch-ticket-w-max));max-width:100%;box-sizing:border-box}.kelvin-scratch--placeholder{width:100%;min-height:calc(var(--scratch-ticket-h-max) + 8rem);pointer-events:none}@media(max-width:767px){.kelvin-scratch{--scratch-ticket-scale: .94}}@media(min-width:768px)and (max-width:1023px){.kelvin-scratch{--scratch-ticket-scale: 1}}@media(min-width:1024px){.kelvin-scratch{--scratch-ticket-scale: 1}}.kelvin-scratch__stage.web-apps-scratch__stage{position:relative;flex-wrap:nowrap;flex-direction:column;align-items:center;justify-content:flex-start;gap:clamp(14px,2.5vh,24px);width:100%;max-width:100%;margin-inline:auto;touch-action:pan-y}.kelvin-scratch__stage--coin-out{cursor:none;-webkit-tap-highlight-color:transparent;-webkit-user-select:none;-moz-user-select:none;user-select:none}.kelvin-scratch__stage--coin-out .kelvin-scratch__ticket-stack,.kelvin-scratch__stage--coin-out .kelvin-scratch__panel,.kelvin-scratch__stage--coin-out .kelvin-scratch-zone{touch-action:none}.kelvin-scratch__coin-cursor-wrap{position:absolute;z-index:30;left:var(--kelvin-coin-x, 50%);top:var(--kelvin-coin-y, 50%);transform:translate(-50%,-50%);width:var(--scratch-coin-size, 64px);height:var(--scratch-coin-size, 64px);line-height:0;pointer-events:none}.kelvin-scratch__coin-cursor-wrap .kelvin-scratch__coin-cursor{position:static;left:auto;top:auto;transform:none}.kelvin-scratch__column{container-type:inline-size;container-name:kelvin-scratch-col;display:flex;flex-direction:column;align-items:center;gap:clamp(4px,1vh,10px);width:var(--scratch-ticket-w, var(--scratch-ticket-w-max));min-width:min(var(--cs-stage-min, 220px),var(--scratch-ticket-w-from-h));max-width:100%;flex:0 0 auto;align-self:center;margin-inline:auto;--scratch-coin-size: clamp(2.75rem, 20cqi, 4.75rem)}.kelvin-scratch__ticket-stack{position:relative;width:100%;aspect-ratio:805.73 / 1274.34;height:auto;max-height:var(--scratch-ticket-h, var(--scratch-ticket-h-max));min-height:min(240px,42dvh);max-width:100%;flex-shrink:0;overflow:hidden}.kelvin-scratch__tray--below{position:static;width:100%;max-width:100%;flex-shrink:0;pointer-events:auto}.kelvin-scratch__tray--below .kelvin-scratch__tray-bar{container-type:inline-size;container-name:kelvin-tray-band;display:grid;grid-template-columns:minmax(0,1fr) auto minmax(0,1fr);grid-template-areas:"take coin leave";align-items:center;width:100%;min-height:clamp(3.25rem,14cqi,5.5rem);padding-block:clamp(8px,2cqi,14px);padding-inline:clamp(10px,3cqi,22px);gap:clamp(8px,2.5cqi,18px);border-radius:10px;background:transparent;transition:background .16s ease}.kelvin-scratch__tray--below .kelvin-scratch__tray-bar.web-apps-scratch__tray-bar--drop{background:transparent;cursor:default}.kelvin-scratch__tray--below .kelvin-scratch__tray-bar.web-apps-scratch__tray-bar--drop:hover{background:var(--color-nav-pill-muted-accent-1)}.kelvin-scratch__tray-action{margin:0;padding:0;border:none;background:transparent;cursor:pointer;font:inherit;color:inherit;pointer-events:auto;-webkit-tap-highlight-color:transparent;touch-action:manipulation}.kelvin-scratch__tray-action:active{background:transparent}.kelvin-scratch__tray-action:disabled{cursor:default;pointer-events:none}.kelvin-scratch__tray-action--take{grid-area:take;container-type:inline-size;container-name:kelvin-tray-label}.kelvin-scratch__tray-action--coin{grid-area:coin;display:flex;align-items:center;justify-content:center;background:transparent;border-radius:0;cursor:pointer}.kelvin-scratch__tray-action--leave{grid-area:leave;container-type:inline-size;container-name:kelvin-tray-label}.kelvin-scratch__tray-action:focus{outline:none}.kelvin-scratch__tray-action:focus:not(:focus-visible){outline:none}.kelvin-scratch__tray-action:focus-visible{outline:2px solid var(--color-accent, #de3e18);outline-offset:2px}.kelvin-scratch__ticket{position:relative;display:block;width:100%;height:100%;max-width:100%;line-height:0}.kelvin-scratch__art{display:block;width:100%;height:100%;-o-object-fit:fill;object-fit:fill;-o-object-position:top center;object-position:top center}.kelvin-scratch__panel{position:absolute;left:var(--kelvin-zone-left);top:var(--kelvin-zone-top);width:var(--kelvin-zone-width);height:var(--kelvin-zone-height);z-index:1;overflow:hidden;pointer-events:none}.kelvin-scratch__stage--coin-out .kelvin-scratch__panel{pointer-events:auto;touch-action:none}.kelvin-scratch-zone{position:relative;width:100%;height:100%;min-height:1px;min-width:1px;touch-action:none;-webkit-tap-highlight-color:transparent;-webkit-user-select:none;-moz-user-select:none;user-select:none}.kelvin-scratch-zone__reveal,.kelvin-scratch-zone__cover{position:absolute;inset:0;display:block;width:100%;height:100%}.kelvin-scratch-zone__reveal{-o-object-fit:contain;object-fit:contain;-o-object-position:center;object-position:center;z-index:0;pointer-events:none}.kelvin-scratch-zone__cover{z-index:1}.kelvin-scratch__tray.web-apps-scratch__tray{width:100%;max-width:100%;align-items:stretch}.kelvin-scratch__tray .web-apps-scratch__tray-phrase-wrap--take{justify-content:flex-end}.kelvin-scratch__tray .web-apps-scratch__tray-phrase-wrap--leave{justify-content:flex-start}.kelvin-scratch__tray .web-apps-scratch__tray-phrase{display:flex;flex-direction:row;flex-wrap:nowrap;align-items:baseline;gap:.25em;width:-moz-max-content;width:max-content;max-width:100%;font-family:var(--font-mono);font-size:11px;font-weight:700;letter-spacing:.06em;line-height:1.15;text-transform:uppercase;pointer-events:none}.kelvin-scratch__tray .web-apps-scratch__tray-phrase-line{display:block;white-space:nowrap}.kelvin-scratch__tray .web-apps-scratch__tray-phrase--take{align-items:flex-end;margin-left:auto;text-align:right}.kelvin-scratch__tray .web-apps-scratch__tray-phrase--leave{align-items:flex-start;margin-right:auto;text-align:left}.kelvin-scratch__tray .web-apps-scratch__tray-phrase{color:var(--color-nav-faded-selection);opacity:1;transition:color .16s ease}.kelvin-scratch__tray-bar.web-apps-scratch__tray-bar--ready .web-apps-scratch__tray-phrase--take,.kelvin-scratch__tray-bar.web-apps-scratch__tray-bar--drop .web-apps-scratch__tray-phrase--leave{color:var(--color-accent, #de3e18)}.kelvin-scratch__tray .web-apps-scratch__tray-coin{grid-area:coin;align-self:center;flex-shrink:0;width:var(--scratch-coin-size, clamp(2.5rem, 18cqi, 4.5rem));height:var(--scratch-coin-size, clamp(2.5rem, 18cqi, 4.5rem));overflow:visible;background:transparent}.kelvin-scratch__tray .web-apps-scratch__tray-coin-img{width:100%;height:100%;transform:none;filter:none;-webkit-user-drag:none;-webkit-user-select:none;-moz-user-select:none;user-select:none}.kelvin-scratch__tray-bar--ready .kelvin-scratch__tray-action--coin:hover .web-apps-scratch__tray-coin-img,.kelvin-scratch__tray-bar--ready .kelvin-scratch__tray-action--coin:focus-visible .web-apps-scratch__tray-coin-img{transform:scale(1.04)}.kelvin-scratch__tray .web-apps-scratch__tray-coin--empty{width:auto;height:auto;min-width:var(--scratch-coin-size, 3rem);min-height:var(--scratch-coin-size, 3rem);display:flex;align-items:center;justify-content:center;background:transparent}.kelvin-scratch__tray .web-apps-scratch__tray-coin-slot{width:clamp(2rem,12cqi,3rem);height:clamp(2rem,12cqi,3rem);background:color-mix(in srgb,var(--color-accent, #de3e18) 22%,transparent)}.kelvin-scratch .web-apps-scratch__coin-cursor{filter:drop-shadow(0 2px 6px rgba(0,0,0,.2));-webkit-tap-highlight-color:transparent;-webkit-user-select:none;-moz-user-select:none;user-select:none}.kelvin-scratch__tray-bar{-webkit-tap-highlight-color:transparent}@container kelvin-tray-label (max-width: 92px){.kelvin-scratch__tray .web-apps-scratch__tray-phrase{flex-direction:column;align-items:inherit;gap:.05em}}@container kelvin-scratch-col (max-width: 300px){.kelvin-scratch__tray--below .kelvin-scratch__tray-bar{gap:clamp(6px,2cqi,12px);padding-inline:clamp(8px,2.5cqi,14px)}}