nit centering and remove unit type from measurements

Author: Adam Argyle

app/components/selection/distance.element.css

@@ -29,18 +29,21 @@
 }
 
 :host > figure figcaption {
+  min-height: 3ex;
   width: max-content;
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
   color: white;
   text-shadow: 0 0.5px 0 hsla(0, 0%, 0%, 0.4);
   box-shadow: 0 0.5px 0 hsla(0, 0%, 0%, 0.4);
   background: var(--line-color);
   border-radius: 1em;
-  text-align: center;
-  line-height: 1.1;
   font-size: 0.7em;
-  font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, sans-serif;
-  padding: 0.25em 0.5em 0.275em;
-  font-variant-numeric: proportional-num oldstyle-nums stacked-fractions slashed-zero;
+  font-weight: bold;
+  line-height: 1.1;
+  font-family: system-ui;
+  padding: 0 1ex;
 }
 
 :host > figure span {

app/components/selection/distance.element.js

@@ -52,7 +52,7 @@ export class Distance extends HTMLElement {
     return `
       <figure quadrant="${q}">
         <div></div>
-        <figcaption><b>${d}</b>px</figcaption>
+        <figcaption>${Math.round(d)}</figcaption>
         <div></div>
       </figure>
     `