refs #15704 [fid_adlr] background shapes

* incorporates background shapes for website main section

themes/fid_adlr/images/background-shape-small.svg

+<?xml version="1.0" encoding="UTF-8"?>
+<svg width="332px" height="263px" viewBox="0 0 332 263" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
+    <!-- Generator: Sketch 54.1 (76490) - https://sketchapp.com -->
+    <title>Combined Shape</title>
+    <desc>Created with Sketch.</desc>
+    <defs>
+        <linearGradient x1="80.6060205%" y1="42.1455999%" x2="15.0675318%" y2="58.3954353%" id="linearGradient-1">
+            <stop stop-color="#0057FF" offset="0%"></stop>
+            <stop stop-color="#32FFDA" offset="100%"></stop>
+        </linearGradient>
+    </defs>
+    <g id="Webdesign-Tablet" stroke="none" stroke-width="1" fill="none" fill-rule="evenodd" opacity="0.243373326">
+        <g id="home" transform="translate(-436.000000, -85.000000)" fill="url(#linearGradient-1)" fill-rule="nonzero">
+            <g id="background" transform="translate(-1.000000, 85.000000)">
+                <path d="M900.607652,-5.16646922 C892.929159,134.317543 777.178363,245.061158 635.513207,245.061158 C493.84805,245.061158 378.097254,134.317543 370.418761,-5.16646922 L482.918457,-5.16646922 C490.363812,72.4083504 555.840712,133.072458 635.513207,133.072458 C715.185702,133.072458 780.662601,72.4083504 788.107957,-5.16646922 L900.607652,-5.16646922 Z" id="Combined-Shape" transform="translate(635.513207, 119.947345) rotate(29.000000) translate(-635.513207, -119.947345) "></path>
+            </g>
+        </g>
+    </g>
+</svg>
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