diff --git a/flask-fox.json b/flask-fox.json
new file mode 100644
index 00000000..3caf74fd
--- /dev/null
+++ b/flask-fox.json
@@ -0,0 +1,603 @@
+{
+  "positions": [
+    [111.0246, 52.6046, 46.2259],
+    [114.025, 87.6733, 58.9818],
+    [66.192, 80.898, 55.3943],
+    [72.1133, 35.4918, 30.8714],
+    [97.8045, 116.561, 73.9788],
+    [16.7623, 58.0109, 58.0782],
+    [52.6089, 30.3641, 42.5561],
+    [106.8814, 31.9455, 46.9133],
+    [113.4846, 38.6049, 49.1215],
+    [108.6633, 43.2332, 46.3154],
+    [101.2166, 15.9822, 46.3082],
+    [16.6605, -16.2883, 93.6187],
+    [40.775, -10.2288, 85.2764],
+    [23.9269, -2.5103, 86.7365],
+    [11.1691, -7.0037, 99.3776],
+    [9.5692, -34.3939, 141.672],
+    [12.596, 7.1655, 88.741],
+    [61.1809, 8.8142, 76.9968],
+    [39.7195, -28.9271, 88.9638],
+    [13.7962, -68.5757, 132.057],
+    [15.2674, -62.32, 129.688],
+    [14.8446, -52.6096, 140.113],
+    [12.8917, -49.7716, 144.741],
+    [35.6042, -71.758, 81.0639],
+    [47.4625, -68.6061, 63.3697],
+    [38.2486, -64.7302, 38.9099],
+    [-12.8917, -49.7716, 144.741],
+    [-13.7962, -68.5757, 132.057],
+    [17.8021, -71.758, 81.0639],
+    [19.1243, -69.0168, 49.4201],
+    [38.2486, -66.2756, 17.7762],
+    [12.8928, -36.7035, 141.672],
+    [109.284, -93.5899, 27.8243],
+    [122.118, -36.8894, 35.025],
+    [67.7668, -30.197, 78.4178],
+    [33.1807, 101.852, 25.3186],
+    [9.4063, -35.5898, 150.722],
+    [-9.5692, -34.3939, 141.672],
+    [-9.4063, -35.5898, 150.722],
+    [11.4565, -37.8994, 150.722],
+    [-12.596, 7.1655, 88.741],
+    [-11.1691, -7.0037, 99.3776],
+    [70.2365, 62.8362, -3.9475],
+    [47.2634, 54.294, -27.4148],
+    [28.7302, 91.7311, -24.9726],
+    [69.1676, 6.5862, -12.7757],
+    [28.7302, 49.1003, -48.3596],
+    [31.903, 5.692, -47.822],
+    [35.0758, -34.4329, -16.2809],
+    [115.2841, 48.6815, 48.6841],
+    [110.8428, 28.4821, 49.1762],
+    [-19.1243, -69.0168, 49.4201],
+    [-38.2486, -66.2756, 17.7762],
+    [-111.0246, 52.6046, 46.2259],
+    [-72.1133, 35.4918, 30.8714],
+    [-66.192, 80.898, 55.3943],
+    [-114.025, 87.6733, 58.9818],
+    [-97.8045, 116.561, 73.9788],
+    [-52.6089, 30.3641, 42.5561],
+    [-16.7623, 58.0109, 58.0782],
+    [-106.8814, 31.9455, 46.9133],
+    [-108.6633, 43.2332, 46.3154],
+    [-113.4846, 38.6049, 49.1215],
+    [-101.2166, 15.9822, 46.3082],
+    [-16.6605, -16.2883, 93.6187],
+    [-23.9269, -2.5103, 86.7365],
+    [-40.775, -10.2288, 85.2764],
+    [-61.1809, 8.8142, 76.9968],
+    [-39.7195, -28.9271, 88.9638],
+    [-14.8446, -52.6096, 140.113],
+    [-15.2674, -62.32, 129.688],
+    [-47.4625, -68.6061, 63.3697],
+    [-35.6042, -71.758, 81.0639],
+    [-38.2486, -64.7302, 38.9099],
+    [-17.8021, -71.758, 81.0639],
+    [-12.8928, -36.7035, 141.672],
+    [-67.7668, -30.197, 78.4178],
+    [-122.118, -36.8894, 35.025],
+    [-109.284, -93.5899, 27.8243],
+    [-33.1807, 101.852, 25.3186],
+    [-11.4565, -37.8994, 150.722],
+    [-70.2365, 62.8362, -3.9475],
+    [-28.7302, 91.7311, -24.9726],
+    [-47.2634, 54.294, -27.4148],
+    [-69.1676, 6.5862, -12.7757],
+    [-28.7302, 49.1003, -48.3596],
+    [-31.903, 5.692, -47.822],
+    [-35.0758, -34.4329, -16.2809],
+    [-115.2841, 48.6815, 48.6841],
+    [-110.8428, 28.4821, 49.1762]
+  ],
+  "chunks": [
+    {
+      "color": [123, 129, 255],
+      "faces": [
+        [17, 33, 10],
+        [17, 18, 34],
+        [34, 33, 17],
+        [10, 6, 17],
+        [11, 15, 31],
+        [31, 18, 11],
+        [18, 12, 11],
+        [14, 16, 40],
+        [40, 41, 14],
+        [59, 5, 35],
+        [35, 79, 59],
+        [67, 63, 77],
+        [67, 77, 76],
+        [76, 68, 67],
+        [63, 67, 58],
+        [64, 68, 75],
+        [75, 37, 64],
+        [68, 64, 66],
+        [14, 41, 37],
+        [37, 15, 14],
+        [5, 59, 40],
+        [40, 16, 5]
+      ],
+      "mask": "mask1",
+      "name": "middle forehead, cheecks, below eyes, top of right ear",
+      "gradient": "paint1_linear"
+    },
+    {
+      "color": [123, 129, 255],
+      "faces": [
+        [31, 24, 18],
+        [6, 5, 16],
+        [16, 17, 6],
+        [24, 32, 33],
+        [33, 34, 24],
+        [5, 4, 35],
+        [75, 68, 71],
+        [58, 67, 40],
+        [40, 59, 58],
+        [71, 76, 77],
+        [77, 78, 71]
+      ],
+      "mask": "mask1",
+      "name": "cheek fluff, forehead",
+      "gradient": "paint10_linear"
+    },
+    {
+      "color": [118, 61, 22],
+      "faces": [
+        [0, 1, 2],
+        [2, 3, 0],
+        [4, 5, 2],
+        [6, 3, 2],
+        [2, 5, 6],
+        [7, 8, 9],
+        [10, 3, 6],
+        [10, 50, 7],
+        [7, 3, 10],
+        [7, 9, 3],
+        [49, 0, 9],
+        [3, 9, 0],
+        [53, 54, 55],
+        [55, 56, 53],
+        [57, 56, 55],
+        [58, 59, 55],
+        [55, 54, 58],
+        [60, 61, 62],
+        [63, 58, 54],
+        [63, 60, 89],
+        [60, 63, 54],
+        [60, 54, 61],
+        [88, 61, 53],
+        [54, 53, 61],
+        [2, 1, 4],
+        [55, 59, 57]
+      ],
+      "mask": "mask1",
+      "name": "ears",
+      "gradient": "paint4_linear"
+    },
+    {
+      "color": [22, 22, 22],
+      "faces": [
+        [36, 15, 37],
+        [37, 38, 36],
+        [31, 39, 22],
+        [22, 21, 31],
+        [31, 15, 36],
+        [36, 39, 31],
+        [75, 69, 26],
+        [26, 80, 75],
+        [75, 80, 38],
+        [38, 37, 75],
+        [38, 80, 39],
+        [39, 36, 38],
+        [39, 80, 26],
+        [26, 22, 39]
+      ],
+      "name": "nose"
+    },
+    {
+      "color": [255, 159, 90],
+      "faces": [
+        [21, 20, 24],
+        [24, 31, 21],
+        [69, 71, 70],
+        [71, 69, 75]
+      ],
+      "name": "upper chin"
+    },
+    {
+      "color": [223, 117, 84],
+      "faces": [
+        [19, 20, 21],
+        [21, 22, 19],
+        [20, 19, 23],
+        [23, 24, 20],
+        [23, 25, 24],
+        [19, 22, 26],
+        [26, 27, 19],
+        [23, 28, 29],
+        [23, 29, 30],
+        [25, 23, 30],
+        [29, 51, 52],
+        [52, 30, 29],
+        [27, 26, 69],
+        [69, 70, 27],
+        [70, 71, 72],
+        [72, 27, 70],
+        [72, 71, 73],
+        [51, 74, 72],
+        [52, 51, 72],
+        [73, 52, 72],
+        [19, 27, 74],
+        [74, 28, 19],
+        [51, 29, 28],
+        [28, 74, 51],
+        [74, 27, 72],
+        [28, 23, 19]
+      ],
+      "name": "chin"
+    },
+    {
+      "color": [82, 88, 230],
+      "faces": [
+        [24, 34, 18],
+        [16, 13, 12],
+        [12, 17, 16],
+        [13, 16, 11],
+        [71, 68, 76],
+        [40, 67, 66],
+        [66, 65, 40],
+        [65, 64, 40]
+      ],
+      "mask": "mask1",
+      "name": "cheeks and surrounding eyes"
+    },
+    {
+      "color": [22, 22, 22],
+      "faces": [
+        [11, 12, 13],
+        [64, 65, 66]
+      ],
+      "name": "eyes"
+    },
+    {
+      "color": [123, 129, 255],
+      "faces": [
+        [14, 15, 11],
+        [11, 16, 14],
+        [17, 12, 18],
+        [41, 64, 37],
+        [67, 68, 66]
+      ],
+      "mask": "mask1",
+      "name": "snout folds"
+    },
+    {
+      "color": [97, 103, 245],
+      "faces": [
+        [35, 4, 42],
+        [4, 1, 42],
+        [42, 43, 44],
+        [44, 35, 42],
+        [45, 43, 42],
+        [42, 10, 45],
+        [30, 32, 24],
+        [24, 25, 30],
+        [30, 33, 32],
+        [33, 30, 10],
+        [44, 43, 46],
+        [43, 45, 47],
+        [47, 46, 43],
+        [48, 47, 45],
+        [45, 30, 48],
+        [30, 45, 10],
+        [49, 42, 0],
+        [8, 7, 42],
+        [50, 42, 7],
+        [50, 10, 42],
+        [1, 0, 42],
+        [42, 9, 8],
+        [42, 49, 9],
+        [64, 41, 40],
+        [57, 59, 79],
+        [79, 81, 57],
+        [57, 81, 56],
+        [82, 79, 35],
+        [35, 44, 82],
+        [81, 79, 82],
+        [82, 83, 81],
+        [84, 63, 81],
+        [81, 83, 84],
+        [44, 46, 85],
+        [85, 82, 44],
+        [52, 73, 71],
+        [71, 78, 52],
+        [52, 78, 77],
+        [77, 63, 52],
+        [82, 85, 83],
+        [83, 85, 86],
+        [86, 84, 83],
+        [87, 52, 84],
+        [84, 86, 87],
+        [52, 63, 84],
+        [88, 53, 81],
+        [62, 81, 60],
+        [89, 60, 81],
+        [89, 81, 63],
+        [56, 81, 53],
+        [81, 62, 61],
+        [81, 61, 88],
+        [48, 87, 86],
+        [86, 47, 48],
+        [47, 86, 85],
+        [85, 46, 47],
+        [48, 30, 52],
+        [52, 87, 48]
+      ],
+      "mask": "mask1",
+      "name": "back, top of right ear"
+    }
+  ],
+  "gradients": {
+    "paint0_linear": {
+      "x1": "17.4996",
+      "y1": "4.16699",
+      "x2": "17.4996",
+      "y2": "26.4153",
+      "gradientUnits": "userSpaceOnUse",
+      "type": "linear",
+      "stops": [
+        {
+          "stop-color": "#7E83FF"
+        },
+        {
+          "offset": "1",
+          "stop-color": "#A1A5FF"
+        }
+      ]
+    },
+    "paint1_linear": {
+      "type": "linear",
+      "x1": "29.3974",
+      "y1": "14.1221",
+      "x2": "29.3974",
+      "y2": "23.7337",
+      "gradientUnits": "userSpaceOnUse",
+      "stops": [
+        {
+          "stop-color": "#555BE9"
+        },
+        {
+          "offset": "1",
+          "stop-color": "#989CFF"
+        }
+      ]
+    },
+    "paint2_linear": {
+      "x1": "5.6088",
+      "y1": "14.1221",
+      "x2": "5.6088",
+      "y2": "23.7337",
+      "gradientUnits": "userSpaceOnUse",
+      "type": "linear",
+      "stops": [
+        {
+          "stop-color": "#555BE9"
+        },
+        {
+          "offset": "1",
+          "stop-color": "#989CFF"
+        }
+      ]
+    },
+    "paint3_linear": {
+      "x1": "24.3725",
+      "y1": "13.4755",
+      "x2": "36.9499",
+      "y2": "3.6613",
+      "gradientUnits": "userSpaceOnUse",
+      "type": "linear",
+      "stops": [
+        {
+          "stop-color": "#070D9B"
+        },
+        {
+          "offset": "1",
+          "stop-color": "#4248D6"
+        }
+      ]
+    },
+    "paint4_linear": {
+      "type": "linear",
+      "gradientUnits": "userSpaceOnUse",
+      "x1": "10.6275",
+      "y1": "13.4755",
+      "x2": "-1.94986",
+      "y2": "3.6613",
+      "stops": [
+        {
+          "stop-color": "#070D9B"
+        },
+        {
+          "stop-color": "#4248D6",
+          "offset": "1"
+        }
+      ]
+    },
+    "paint5_linear": {
+      "type": "linear",
+      "gradientUnits": "userSpaceOnUse",
+      "x1": "29.7202",
+      "y1": "23.6787",
+      "x2": "29.7202",
+      "y2": "31.2827",
+      "stops": [
+        {
+          "stop-color": "#787878"
+        },
+        {
+          "stop-color": "#5E5E5E",
+          "offset": "1"
+        }
+      ]
+    },
+    "paint6_linear": {
+      "type": "linear",
+      "gradientUnits": "userSpaceOnUse",
+      "x1": "5.28661",
+      "y1": "23.6787",
+      "x2": "5.28661",
+      "y2": "31.2827",
+      "stops": [
+        {
+          "stop-color": "#787878"
+        },
+        {
+          "stop-color": "#5E5E5E",
+          "offset": "1"
+        }
+      ]
+    },
+    "paint7_linear": {
+      "type": "linear",
+      "gradientUnits": "userSpaceOnUse",
+      "x1": "11.5473",
+      "y1": "9.81738",
+      "x2": "11.5473",
+      "y2": "17.7514",
+      "stops": [
+        {
+          "stop-color": "#7A7A7A"
+        },
+        {
+          "stop-color": "#949494",
+          "offset": "1"
+        }
+      ]
+    },
+    "paint8_linear": {
+      "type": "linear",
+      "gradientUnits": "userSpaceOnUse",
+      "x1": "23.4521",
+      "y1": "9.81738",
+      "x2": "23.4521",
+      "y2": "17.7514",
+      "stops": [
+        {
+          "stop-color": "#7A7A7A"
+        },
+        {
+          "stop-color": "#949494",
+          "offset": "1"
+        }
+      ]
+    },
+    "paint9_linear": {
+      "type": "linear",
+      "gradientUnits": "userSpaceOnUse",
+      "x1": "12.6116",
+      "y1": "32.3962",
+      "x2": "12.6116",
+      "y2": "-3.33511",
+      "stops": [
+        {
+          "stop-color": "#7A7C7D"
+        },
+        {
+          "stop-color": "#CECECF",
+          "offset": "1"
+        }
+      ]
+    },
+    "paint10_linear": {
+      "type": "linear",
+      "gradientUnits": "userSpaceOnUse",
+      "x1": "22.3884",
+      "y1": "32.3962",
+      "x2": "22.3884",
+      "y2": "-3.33511",
+      "stops": [
+        {
+          "stop-color": "#686EFC"
+        },
+        {
+          "stop-color": "#C7C9FF",
+          "offset": "1"
+        }
+      ]
+    },
+    "paint11_linear": {
+      "type": "linear",
+      "gradientUnits": "userSpaceOnUse",
+      "x1": "26.2118",
+      "y1": "16.7209",
+      "x2": "26.2118",
+      "y2": "30.8694",
+      "stops": [
+        {
+          "stop-color": "#3E3E3E"
+        },
+        {
+          "stop-color": "#616161",
+          "offset": "1"
+        }
+      ]
+    },
+    "paint12_linear": {
+      "type": "linear",
+      "gradientUnits": "userSpaceOnUse",
+      "x1": "8.78767",
+      "y1": "16.7209",
+      "x2": "8.78767",
+      "y2": "30.8694",
+      "stops": [
+        {
+          "stop-color": "#3E3E3E"
+        },
+        {
+          "stop-color": "#616161",
+          "offset": "1"
+        }
+      ]
+    },
+    "paint13_linear": {
+      "type": "linear",
+      "gradientUnits": "userSpaceOnUse",
+      "x1": "17.4382",
+      "y1": "4.12515",
+      "x2": "17.4382",
+      "y2": "34.1012",
+      "stops": [
+        {
+          "stop-color": "#FF60DC"
+        },
+        {
+          "stop-color": "#6B71FF",
+          "offset": "1"
+        }
+      ]
+    },
+    "paint14_radial": {
+      "cx": "50%",
+      "cy": "0",
+      "r": "70%",
+      "gradientUnits": "userSpaceOnUse",
+      "type": "radial",
+      "stops": [
+        {
+          "stop-color": "rgb(255,255,255)"
+        },
+        {
+          "offset": "1",
+          "stop-color": "rbg(0,0,0)"
+        }
+      ]
+    }
+  },
+  "masks": {
+    "mask1": {
+      "modelColor": "rgb(255,96,220)",
+      "maskColor": "url('#paint14_radial')"
+    }
+  }
+}
diff --git a/index.js b/index.js
index fc8f64bd..0b99fe40 100644
--- a/index.js
+++ b/index.js
@@ -22,6 +22,7 @@ function createLogo(options = {}) {
   document.body.appendChild(container);
 
   setGradientDefinitions(container, meshJson.gradients);
+  setMaskDefinitions(container, meshJson.masks, height, width);
 
   const modelObj = loadModelFromJson(meshJson);
   const renderFox = createModelRenderer(container, cameraDistance, modelObj);
@@ -36,3 +37,24 @@ function createLogo(options = {}) {
     Object.assign({ cameraDistance }, options),
   );
 }
+
+function setMaskDefinitions(container, masks, height, width) {
+  for (const [maskId, maskDefinition] of Object.entries(masks)) {
+    const mask = createNode('mask');
+    setAttribute(mask, 'id', maskId);
+
+    const maskedRect = createNode('rect');
+
+    // Extend mask beyond container to ensure it completely covers the model.
+    // The model can extend beyond the container as well.
+    setAttribute(maskedRect, 'width', width * 1.5);
+    setAttribute(maskedRect, 'height', height * 1.5);
+    setAttribute(maskedRect, 'x', `-${Math.floor(width / 4)}`);
+    setAttribute(maskedRect, 'y', `-${Math.floor(height / 4)}`);
+
+    setAttribute(maskedRect, 'fill', maskDefinition.maskColor);
+    mask.appendChild(maskedRect);
+
+    container.appendChild(mask);
+  }
+}
diff --git a/util.js b/util.js
index 027af70d..fcaeb143 100644
--- a/util.js
+++ b/util.js
@@ -269,7 +269,7 @@ function createModelRenderer(container, cameraDistance, modelObj) {
   return (rect, lookPos, slowDrift) => {
     const matrix = computeMatrix(rect, lookPos, slowDrift);
     updatePositions(matrix);
-    updateFaces(rect, container, polygons, transformed);
+    updateFaces(rect);
   };
 }
 
@@ -288,13 +288,25 @@ function positionsFromModel(positions, modelJson) {
 function createPolygonsFromModelJson(modelJson, createSvgPolygon) {
   const polygons = [];
   const polygonsByChunk = modelJson.chunks.map((chunk, index) => {
-    const { faces } = chunk;
+    const { faces, mask: maskId } = chunk;
     return faces.map((face) => {
       const svgPolygon = createSvgPolygon(chunk, {
         gradients: modelJson.gradients,
         index,
       });
-      const polygon = new Polygon(svgPolygon, face);
+      let maskPolygon;
+      if (maskId) {
+        if (modelJson.masks[maskId] === undefined) {
+          throw new Error(`Unrecognized mask ID: '${maskId}'`);
+        }
+
+        maskPolygon = createSvgPolygon(chunk, {
+          gradients: modelJson.gradients,
+          mask: modelJson.masks[maskId],
+          index,
+        });
+      }
+      const polygon = new Polygon(svgPolygon, face, maskPolygon);
       polygons.push(polygon);
       return polygon;
     });
@@ -314,16 +326,21 @@ function createPolygonsFromModelJson(modelJson, createSvgPolygon) {
  * @param {object} options - Polygon options.
  * @param {(LinearGradientDefinition | RadialGradientDefinition)[]} [options.gradients] - The set of
  * all gradient definitions used in this model.
- * @param options.index - The index for the chunk this polygon is found in.
+ * @param {number} options.index - The index for the chunk this polygon is found in.
+ * @param {object} [options.mask] - The mask definition to use for this polygon.
  * @returns {Element} The `<polygon>` SVG element.
  */
-function createStandardModelPolygon(chunk, { gradients = {}, index }) {
+function createStandardModelPolygon(chunk, { gradients = {}, index, mask }) {
   const svgPolygon = createNode('polygon');
 
   if (chunk.gradient && chunk.color) {
     throw new Error(
       `Both gradient and color for chunk '${index}'. These options are mutually exclusive.`,
     );
+  } else if (mask) {
+    setAttribute(svgPolygon, 'mask', `url('#${chunk.mask}')`);
+    setAttribute(svgPolygon, 'fill', mask.modelColor);
+    setAttribute(svgPolygon, 'stroke', mask.modelColor);
   } else if (chunk.gradient) {
     const gradientId = chunk.gradient;
     if (!gradients[gradientId]) {
@@ -461,7 +478,6 @@ function createFaceUpdater(container, polygons, transformed) {
       const points = [];
       let zmax = -Infinity;
       let zmin = Infinity;
-      const element = poly.svg;
       for (let j = 0; j < 3; ++j) {
         const idx = indices[j];
         points.push(
@@ -473,20 +489,26 @@ function createFaceUpdater(container, polygons, transformed) {
         zmax = Math.max(zmax, z);
         zmin = Math.min(zmin, z);
       }
+
       poly.zIndex = zmax + 0.25 * zmin;
       const joinedPoints = points.join(' ');
 
       if (joinedPoints.indexOf('NaN') === -1) {
-        setAttribute(element, 'points', joinedPoints);
+        setAttribute(poly.svg, 'points', joinedPoints);
+        if (poly.maskSvg) {
+          setAttribute(poly.maskSvg, 'points', joinedPoints);
+        }
       }
-
       toDraw.push(poly);
     }
     toDraw.sort(compareZ);
 
-    const newPolygons = toDraw.map((poly) => poly.svg);
+    const newPolygons = toDraw
+      .map((poly) => [poly.svg, ...(poly.maskSvg ? [poly.maskSvg] : [])])
+      .flat();
     const defs = container.getElementsByTagName('defs');
-    container.replaceChildren(...defs, ...newPolygons);
+    const maskChildren = container.getElementsByTagName('mask');
+    container.replaceChildren(...defs, ...maskChildren, ...newPolygons);
   };
 }
 
@@ -524,10 +546,13 @@ function svgElementToSvgImageContent(svgElement) {
   return content;
 }
 
-function Polygon(svg, indices) {
+function Polygon(svg, indices, maskSvg) {
   this.svg = svg;
   this.indices = indices;
   this.zIndex = 0;
+  if (maskSvg) {
+    this.maskSvg = maskSvg;
+  }
 }
 
 /**