diff --git a/readme.md b/readme.md
index 373a6d7..b3e0361 100644
--- a/readme.md
+++ b/readme.md
@@ -3,7 +3,7 @@
 [![Netlify Status](https://api.netlify.com/api/v1/badges/42b5fd04-c538-4e3c-bd69-73e383989cfd/deploy-status)](https://app.netlify.com/sites/ptable-elements/deploys)
 [![pre-commit.ci status](https://results.pre-commit.ci/badge/github/janosh/periodic-table/main.svg?badge_token=nUqJfPCFS4uyMwcFSDIfdQ)](https://results.pre-commit.ci/latest/github/janosh/periodic-table/main?badge_token=nUqJfPCFS4uyMwcFSDIfdQ)
 
-A dynamic Periodic Table component written in Svelte.
+Interactive Periodic Table component written in Svelte.
 
 ![Screenshot of periodic table](static/2022-06-01-screenshot.png)
 
diff --git a/src/colors.ts b/src/colors.ts
index 70b9500..13e8b6a 100644
--- a/src/colors.ts
+++ b/src/colors.ts
@@ -1,4 +1,4 @@
-export const category_colors: Record<string, string> = {
+export const default_category_colors: Record<string, string> = {
   'diatomic-nonmetal': `#ff8c00`, // darkorange
   'noble-gas': `#9932cc`, // darkorchid
   'alkali-metal': `#006400`, // darkgreen
@@ -11,3 +11,6 @@ export const category_colors: Record<string, string> = {
   actinide: `#6495ed`, // cornflowerblue
   experimental: `#808080`, // gray
 }
+export const category_colors: Record<string, string> = {
+  ...default_category_colors,
+}
diff --git a/src/lib/ColorCustomizer.svelte b/src/lib/ColorCustomizer.svelte
index a9f9c72..a8e2bb2 100644
--- a/src/lib/ColorCustomizer.svelte
+++ b/src/lib/ColorCustomizer.svelte
@@ -1,6 +1,6 @@
 <script lang="ts">
   import { fade } from 'svelte/transition'
-  import { category_colors } from '../colors'
+  import { category_colors, default_category_colors } from '../colors'
   import { active_category } from '../stores'
 
   export let open = false
@@ -13,14 +13,14 @@
   }
 </script>
 
+<h2
+  on:click={() => (open = !open)}
+  title={!open && collapsible ? `Click to open color picker` : null}
+  style:cursor={collapsible ? `pointer` : `default`}
+>
+  Customize Colors
+</h2>
 <div class="grid">
-  <h2
-    on:click={() => (open = !open)}
-    title={!open && collapsible ? `Click to open color picker` : null}
-    style:cursor={collapsible ? `pointer` : `default`}
-  >
-    Customize Colors
-  </h2>
   {#if open || !collapsible}
     {#each Object.keys(category_colors) as category}
       <label
@@ -37,6 +37,14 @@
           bind:value={category_colors[category]}
         />
         {category.replaceAll(`-`, ` `)}
+        {#if category_colors[category] !== default_category_colors[category]}
+          <button
+            on:click={() =>
+              (category_colors[category] = default_category_colors[category])}
+          >
+            <small>reset</small>
+          </button>
+        {/if}
       </label>
     {/each}
   {/if}
@@ -68,7 +76,16 @@
     cursor: pointer;
   }
   h2 {
-    margin: 0;
-    white-space: nowrap;
+    text-align: center;
+  }
+  label > button {
+    background: none;
+    border: none;
+    color: white;
+    opacity: 0;
+    transition: 0.3s;
+  }
+  label:hover > button {
+    opacity: 0.5;
   }
 </style>
diff --git a/src/lib/ElementTile.svelte b/src/lib/ElementTile.svelte
index 7fd6034..3fa6254 100644
--- a/src/lib/ElementTile.svelte
+++ b/src/lib/ElementTile.svelte
@@ -3,7 +3,7 @@
   import { Element } from '../types'
 
   export let element: Element
-  export let bg_color: string
+  export let bg_color: string | null
   export let style = ``
   export let show_number = true
   export let show_name = true
@@ -11,12 +11,13 @@
   export let precision = 2
 
   $: category = element.category.replaceAll(` `, `-`)
+  // background color defaults to category color (initialized in colors.ts, user editable in ColorCustomizer.ts)
+  $: bg_color = bg_color ?? `var(--${category}-bg-color)`
 </script>
 
 <div
   class="element-tile {category}"
-  class:active={$active_category === element.category.replaceAll(` `, `-`) ||
-    $active_element?.name === element.name}
+  class:active={$active_category === category || $active_element?.name === element.name}
   {style}
   style:background-color={bg_color}
 >
diff --git a/src/lib/PeriodicTable.svelte b/src/lib/PeriodicTable.svelte
index bf08148..73d296b 100644
--- a/src/lib/PeriodicTable.svelte
+++ b/src/lib/PeriodicTable.svelte
@@ -1,5 +1,4 @@
 <script lang="ts">
-  import { category_colors } from '../colors'
   import elements from '../periodic-table-data.ts'
   import { active_element, color_scale, heatmap } from '../stores'
   import ColorCustomizer from './ColorCustomizer.svelte'
@@ -23,9 +22,8 @@
 
   {#each elements as element}
     {@const value = element[$heatmap]}
-    {@const heatmap_color = value ? $color_scale(value) : `transparent`}
-    {@const default_color = category_colors[element.category.replaceAll(` `, `-`)]}
-    {@const bg_color = $heatmap ? heatmap_color : default_color}
+    {@const heatmap_color = value ? $color_scale?.(value) : `transparent`}
+    {@const bg_color = $heatmap ? heatmap_color : null}
     <a
       href={element.name.toLowerCase()}
       style="grid-column: {element.column}; grid-row: {element.row};"
diff --git a/src/periodic-table-data.ts b/src/periodic-table-data.ts
index 30ef990..004dc3d 100644
--- a/src/periodic-table-data.ts
+++ b/src/periodic-table-data.ts
@@ -28,7 +28,6 @@ export default [
     n_neutrons: 0,
     n_protons: 1,
     n_electrons: 1,
-    group: 1,
     radioactive: null,
     natural: true,
     metal: null,
@@ -73,7 +72,6 @@ export default [
     n_neutrons: 2,
     n_protons: 2,
     n_electrons: 2,
-    group: 18,
     radioactive: null,
     natural: true,
     metal: null,
@@ -118,7 +116,6 @@ export default [
     n_neutrons: 4,
     n_protons: 3,
     n_electrons: 3,
-    group: 1,
     radioactive: null,
     natural: true,
     metal: true,
@@ -163,7 +160,6 @@ export default [
     n_neutrons: 5,
     n_protons: 4,
     n_electrons: 4,
-    group: 2,
     radioactive: null,
     natural: true,
     metal: true,
@@ -208,7 +204,6 @@ export default [
     n_neutrons: 6,
     n_protons: 5,
     n_electrons: 5,
-    group: 13,
     radioactive: null,
     natural: true,
     metal: null,
@@ -253,7 +248,6 @@ export default [
     n_neutrons: 6,
     n_protons: 6,
     n_electrons: 6,
-    group: 14,
     radioactive: null,
     natural: true,
     metal: null,
@@ -298,7 +292,6 @@ export default [
     n_neutrons: 7,
     n_protons: 7,
     n_electrons: 7,
-    group: 15,
     radioactive: null,
     natural: true,
     metal: null,
@@ -345,7 +338,6 @@ export default [
     n_neutrons: 8,
     n_protons: 8,
     n_electrons: 8,
-    group: 16,
     radioactive: null,
     natural: true,
     metal: null,
@@ -392,7 +384,6 @@ export default [
     n_neutrons: 10,
     n_protons: 9,
     n_electrons: 9,
-    group: 17,
     radioactive: null,
     natural: true,
     metal: null,
@@ -440,7 +431,6 @@ export default [
     n_neutrons: 10,
     n_protons: 10,
     n_electrons: 10,
-    group: 18,
     radioactive: null,
     natural: true,
     metal: null,
@@ -488,7 +478,6 @@ export default [
     n_neutrons: 12,
     n_protons: 11,
     n_electrons: 11,
-    group: 1,
     radioactive: null,
     natural: true,
     metal: true,
@@ -536,7 +525,6 @@ export default [
     n_neutrons: 12,
     n_protons: 12,
     n_electrons: 12,
-    group: 2,
     radioactive: null,
     natural: true,
     metal: true,
@@ -584,7 +572,6 @@ export default [
     n_neutrons: 14,
     n_protons: 13,
     n_electrons: 13,
-    group: 13,
     radioactive: null,
     natural: true,
     metal: true,
@@ -632,7 +619,6 @@ export default [
     n_neutrons: 14,
     n_protons: 14,
     n_electrons: 14,
-    group: 14,
     radioactive: null,
     natural: true,
     metal: null,
@@ -680,7 +666,6 @@ export default [
     n_neutrons: 16,
     n_protons: 15,
     n_electrons: 15,
-    group: 15,
     radioactive: null,
     natural: true,
     metal: null,
@@ -728,7 +713,6 @@ export default [
     n_neutrons: 16,
     n_protons: 16,
     n_electrons: 16,
-    group: 16,
     radioactive: null,
     natural: true,
     metal: null,
@@ -776,7 +760,6 @@ export default [
     n_neutrons: 18,
     n_protons: 17,
     n_electrons: 17,
-    group: 17,
     radioactive: null,
     natural: true,
     metal: null,
@@ -824,7 +807,6 @@ export default [
     n_neutrons: 22,
     n_protons: 18,
     n_electrons: 18,
-    group: 18,
     radioactive: null,
     natural: true,
     metal: null,
@@ -872,7 +854,6 @@ export default [
     n_neutrons: 20,
     n_protons: 19,
     n_electrons: 19,
-    group: 1,
     radioactive: null,
     natural: true,
     metal: true,
@@ -920,7 +901,6 @@ export default [
     n_neutrons: 20,
     n_protons: 20,
     n_electrons: 20,
-    group: 2,
     radioactive: null,
     natural: true,
     metal: true,
@@ -969,7 +949,6 @@ export default [
     n_neutrons: 24,
     n_protons: 21,
     n_electrons: 21,
-    group: 3,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1018,7 +997,6 @@ export default [
     n_neutrons: 26,
     n_protons: 22,
     n_electrons: 22,
-    group: 4,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1067,7 +1045,6 @@ export default [
     n_neutrons: 28,
     n_protons: 23,
     n_electrons: 23,
-    group: 5,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1116,7 +1093,6 @@ export default [
     n_neutrons: 28,
     n_protons: 24,
     n_electrons: 24,
-    group: 6,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1165,7 +1141,6 @@ export default [
     n_neutrons: 30,
     n_protons: 25,
     n_electrons: 25,
-    group: 7,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1214,7 +1189,6 @@ export default [
     n_neutrons: 30,
     n_protons: 26,
     n_electrons: 26,
-    group: 8,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1263,7 +1237,6 @@ export default [
     n_neutrons: 32,
     n_protons: 27,
     n_electrons: 27,
-    group: 9,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1312,7 +1285,6 @@ export default [
     n_neutrons: 31,
     n_protons: 28,
     n_electrons: 28,
-    group: 10,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1361,7 +1333,6 @@ export default [
     n_neutrons: 35,
     n_protons: 29,
     n_electrons: 29,
-    group: 11,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1409,7 +1380,6 @@ export default [
     n_neutrons: 35,
     n_protons: 30,
     n_electrons: 30,
-    group: 12,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1454,7 +1424,6 @@ export default [
     n_neutrons: 39,
     n_protons: 31,
     n_electrons: 31,
-    group: 13,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1499,7 +1468,6 @@ export default [
     n_neutrons: 41,
     n_protons: 32,
     n_electrons: 32,
-    group: 14,
     radioactive: null,
     natural: true,
     metal: null,
@@ -1544,7 +1512,6 @@ export default [
     n_neutrons: 42,
     n_protons: 33,
     n_electrons: 33,
-    group: 15,
     radioactive: null,
     natural: true,
     metal: null,
@@ -1589,7 +1556,6 @@ export default [
     n_neutrons: 45,
     n_protons: 34,
     n_electrons: 34,
-    group: 16,
     radioactive: null,
     natural: true,
     metal: null,
@@ -1634,7 +1600,6 @@ export default [
     n_neutrons: 45,
     n_protons: 35,
     n_electrons: 35,
-    group: 17,
     radioactive: null,
     natural: true,
     metal: null,
@@ -1683,7 +1648,6 @@ export default [
     n_neutrons: 48,
     n_protons: 36,
     n_electrons: 36,
-    group: 18,
     radioactive: null,
     natural: true,
     metal: null,
@@ -1730,7 +1694,6 @@ export default [
     n_neutrons: 48,
     n_protons: 37,
     n_electrons: 37,
-    group: 1,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1777,7 +1740,6 @@ export default [
     n_neutrons: 50,
     n_protons: 38,
     n_electrons: 38,
-    group: 2,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1825,7 +1787,6 @@ export default [
     n_neutrons: 50,
     n_protons: 39,
     n_electrons: 39,
-    group: 3,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1870,7 +1831,6 @@ export default [
     n_neutrons: 51,
     n_protons: 40,
     n_electrons: 40,
-    group: 4,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1915,7 +1875,6 @@ export default [
     n_neutrons: 52,
     n_protons: 41,
     n_electrons: 41,
-    group: 5,
     radioactive: null,
     natural: true,
     metal: true,
@@ -1964,7 +1923,6 @@ export default [
     n_neutrons: 54,
     n_protons: 42,
     n_electrons: 42,
-    group: 6,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2009,7 +1967,6 @@ export default [
     n_neutrons: 55,
     n_protons: 43,
     n_electrons: 43,
-    group: 7,
     radioactive: true,
     natural: null,
     metal: true,
@@ -2054,7 +2011,6 @@ export default [
     n_neutrons: 57,
     n_protons: 44,
     n_electrons: 44,
-    group: 8,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2099,7 +2055,6 @@ export default [
     n_neutrons: 58,
     n_protons: 45,
     n_electrons: 45,
-    group: 9,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2144,7 +2099,6 @@ export default [
     n_neutrons: 60,
     n_protons: 46,
     n_electrons: 46,
-    group: 10,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2189,7 +2143,6 @@ export default [
     n_neutrons: 61,
     n_protons: 47,
     n_electrons: 47,
-    group: 11,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2234,7 +2187,6 @@ export default [
     n_neutrons: 64,
     n_protons: 48,
     n_electrons: 48,
-    group: 12,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2279,7 +2231,6 @@ export default [
     n_neutrons: 66,
     n_protons: 49,
     n_electrons: 49,
-    group: 13,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2324,7 +2275,6 @@ export default [
     n_neutrons: 69,
     n_protons: 50,
     n_electrons: 50,
-    group: 14,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2369,7 +2319,6 @@ export default [
     n_neutrons: 71,
     n_protons: 51,
     n_electrons: 51,
-    group: 15,
     radioactive: null,
     natural: true,
     metal: null,
@@ -2414,7 +2363,6 @@ export default [
     n_neutrons: 76,
     n_protons: 52,
     n_electrons: 52,
-    group: 16,
     radioactive: null,
     natural: true,
     metal: null,
@@ -2459,7 +2407,6 @@ export default [
     n_neutrons: 74,
     n_protons: 53,
     n_electrons: 53,
-    group: 17,
     radioactive: null,
     natural: true,
     metal: null,
@@ -2504,7 +2451,6 @@ export default [
     n_neutrons: 77,
     n_protons: 54,
     n_electrons: 54,
-    group: 18,
     radioactive: null,
     natural: true,
     metal: null,
@@ -2549,7 +2495,6 @@ export default [
     n_neutrons: 78,
     n_protons: 55,
     n_electrons: 55,
-    group: 1,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2594,7 +2539,6 @@ export default [
     n_neutrons: 81,
     n_protons: 56,
     n_electrons: 56,
-    group: 2,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2639,7 +2583,6 @@ export default [
     n_neutrons: 82,
     n_protons: 57,
     n_electrons: 57,
-    group: 3,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2684,7 +2627,6 @@ export default [
     n_neutrons: 82,
     n_protons: 58,
     n_electrons: 58,
-    group: null,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2729,7 +2671,6 @@ export default [
     n_neutrons: 82,
     n_protons: 59,
     n_electrons: 59,
-    group: null,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2774,7 +2715,6 @@ export default [
     n_neutrons: 84,
     n_protons: 60,
     n_electrons: 60,
-    group: null,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2819,7 +2759,6 @@ export default [
     n_neutrons: 84,
     n_protons: 61,
     n_electrons: 61,
-    group: null,
     radioactive: true,
     natural: null,
     metal: true,
@@ -2864,7 +2803,6 @@ export default [
     n_neutrons: 88,
     n_protons: 62,
     n_electrons: 62,
-    group: null,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2909,7 +2847,6 @@ export default [
     n_neutrons: 89,
     n_protons: 63,
     n_electrons: 63,
-    group: null,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2954,7 +2891,6 @@ export default [
     n_neutrons: 93,
     n_protons: 64,
     n_electrons: 64,
-    group: null,
     radioactive: null,
     natural: true,
     metal: true,
@@ -2999,7 +2935,6 @@ export default [
     n_neutrons: 94,
     n_protons: 65,
     n_electrons: 65,
-    group: null,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3044,7 +2979,6 @@ export default [
     n_neutrons: 97,
     n_protons: 66,
     n_electrons: 66,
-    group: null,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3089,7 +3023,6 @@ export default [
     n_neutrons: 98,
     n_protons: 67,
     n_electrons: 67,
-    group: null,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3134,7 +3067,6 @@ export default [
     n_neutrons: 99,
     n_protons: 68,
     n_electrons: 68,
-    group: null,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3179,7 +3111,6 @@ export default [
     n_neutrons: 100,
     n_protons: 69,
     n_electrons: 69,
-    group: null,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3224,7 +3155,6 @@ export default [
     n_neutrons: 103,
     n_protons: 70,
     n_electrons: 70,
-    group: null,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3269,7 +3199,6 @@ export default [
     n_neutrons: 104,
     n_protons: 71,
     n_electrons: 71,
-    group: null,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3314,7 +3243,6 @@ export default [
     n_neutrons: 106,
     n_protons: 72,
     n_electrons: 72,
-    group: 4,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3359,7 +3287,6 @@ export default [
     n_neutrons: 108,
     n_protons: 73,
     n_electrons: 73,
-    group: 5,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3404,7 +3331,6 @@ export default [
     n_neutrons: 110,
     n_protons: 74,
     n_electrons: 74,
-    group: 6,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3449,7 +3375,6 @@ export default [
     n_neutrons: 111,
     n_protons: 75,
     n_electrons: 75,
-    group: 7,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3494,7 +3419,6 @@ export default [
     n_neutrons: 114,
     n_protons: 76,
     n_electrons: 76,
-    group: 8,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3539,7 +3463,6 @@ export default [
     n_neutrons: 115,
     n_protons: 77,
     n_electrons: 77,
-    group: 9,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3584,7 +3507,6 @@ export default [
     n_neutrons: 117,
     n_protons: 78,
     n_electrons: 78,
-    group: 10,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3629,7 +3551,6 @@ export default [
     n_neutrons: 118,
     n_protons: 79,
     n_electrons: 79,
-    group: 11,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3674,7 +3595,6 @@ export default [
     n_neutrons: 121,
     n_protons: 80,
     n_electrons: 80,
-    group: 12,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3719,7 +3639,6 @@ export default [
     n_neutrons: 123,
     n_protons: 81,
     n_electrons: 81,
-    group: 13,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3764,7 +3683,6 @@ export default [
     n_neutrons: 125,
     n_protons: 82,
     n_electrons: 82,
-    group: 14,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3809,7 +3727,6 @@ export default [
     n_neutrons: 126,
     n_protons: 83,
     n_electrons: 83,
-    group: 15,
     radioactive: null,
     natural: true,
     metal: true,
@@ -3854,7 +3771,6 @@ export default [
     n_neutrons: 126,
     n_protons: 84,
     n_electrons: 84,
-    group: 16,
     radioactive: true,
     natural: true,
     metal: null,
@@ -3899,7 +3815,6 @@ export default [
     n_neutrons: 125,
     n_protons: 85,
     n_electrons: 85,
-    group: 17,
     radioactive: true,
     natural: true,
     metal: null,
@@ -3944,7 +3859,6 @@ export default [
     n_neutrons: 136,
     n_protons: 86,
     n_electrons: 86,
-    group: 18,
     radioactive: true,
     natural: true,
     metal: true,
@@ -3989,7 +3903,6 @@ export default [
     n_neutrons: 136,
     n_protons: 87,
     n_electrons: 87,
-    group: 1,
     radioactive: true,
     natural: true,
     metal: true,
@@ -4034,7 +3947,6 @@ export default [
     n_neutrons: 138,
     n_protons: 88,
     n_electrons: 88,
-    group: 2,
     radioactive: true,
     natural: true,
     metal: true,
@@ -4079,7 +3991,6 @@ export default [
     n_neutrons: 138,
     n_protons: 89,
     n_electrons: 89,
-    group: 3,
     radioactive: true,
     natural: true,
     metal: true,
@@ -4124,7 +4035,6 @@ export default [
     n_neutrons: 142,
     n_protons: 90,
     n_electrons: 90,
-    group: null,
     radioactive: true,
     natural: true,
     metal: true,
@@ -4169,7 +4079,6 @@ export default [
     n_neutrons: 140,
     n_protons: 91,
     n_electrons: 91,
-    group: null,
     radioactive: true,
     natural: true,
     metal: true,
@@ -4214,7 +4123,6 @@ export default [
     n_neutrons: 146,
     n_protons: 92,
     n_electrons: 92,
-    group: null,
     radioactive: true,
     natural: true,
     metal: true,
@@ -4259,7 +4167,6 @@ export default [
     n_neutrons: 144,
     n_protons: 93,
     n_electrons: 93,
-    group: null,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4304,7 +4211,6 @@ export default [
     n_neutrons: 150,
     n_protons: 94,
     n_electrons: 94,
-    group: null,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4349,7 +4255,6 @@ export default [
     n_neutrons: 148,
     n_protons: 95,
     n_electrons: 95,
-    group: null,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4394,7 +4299,6 @@ export default [
     n_neutrons: 151,
     n_protons: 96,
     n_electrons: 96,
-    group: null,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4439,7 +4343,6 @@ export default [
     n_neutrons: 150,
     n_protons: 97,
     n_electrons: 97,
-    group: null,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4484,7 +4387,6 @@ export default [
     n_neutrons: 153,
     n_protons: 98,
     n_electrons: 98,
-    group: null,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4529,7 +4431,6 @@ export default [
     n_neutrons: 153,
     n_protons: 99,
     n_electrons: 99,
-    group: null,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4574,7 +4475,6 @@ export default [
     n_neutrons: 157,
     n_protons: 100,
     n_electrons: 100,
-    group: null,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4619,7 +4519,6 @@ export default [
     n_neutrons: 157,
     n_protons: 101,
     n_electrons: 101,
-    group: null,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4664,7 +4563,6 @@ export default [
     n_neutrons: 157,
     n_protons: 102,
     n_electrons: 102,
-    group: null,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4709,7 +4607,6 @@ export default [
     n_neutrons: 159,
     n_protons: 103,
     n_electrons: 103,
-    group: null,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4754,7 +4651,6 @@ export default [
     n_neutrons: 157,
     n_protons: 104,
     n_electrons: 104,
-    group: 4,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4799,7 +4695,6 @@ export default [
     n_neutrons: 157,
     n_protons: 105,
     n_electrons: 105,
-    group: 5,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4844,7 +4739,6 @@ export default [
     n_neutrons: 160,
     n_protons: 106,
     n_electrons: 106,
-    group: 6,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4889,7 +4783,6 @@ export default [
     n_neutrons: 157,
     n_protons: 107,
     n_electrons: 107,
-    group: 7,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4934,7 +4827,6 @@ export default [
     n_neutrons: 159,
     n_protons: 108,
     n_electrons: 108,
-    group: 8,
     radioactive: true,
     natural: null,
     metal: true,
@@ -4979,7 +4871,6 @@ export default [
     n_neutrons: 159,
     n_protons: 109,
     n_electrons: 109,
-    group: 9,
     radioactive: true,
     natural: null,
     metal: true,
@@ -5024,7 +4915,6 @@ export default [
     n_neutrons: 161,
     n_protons: 110,
     n_electrons: 110,
-    group: 10,
     radioactive: true,
     natural: null,
     metal: true,
@@ -5069,7 +4959,6 @@ export default [
     n_neutrons: 161,
     n_protons: 111,
     n_electrons: 111,
-    group: 11,
     radioactive: true,
     natural: null,
     metal: true,
@@ -5114,7 +5003,6 @@ export default [
     n_neutrons: 173,
     n_protons: 112,
     n_electrons: 112,
-    group: 12,
     radioactive: true,
     natural: null,
     metal: true,
@@ -5159,7 +5047,6 @@ export default [
     n_neutrons: 171,
     n_protons: 113,
     n_electrons: 113,
-    group: 13,
     radioactive: true,
     natural: null,
     metal: true,
@@ -5204,7 +5091,6 @@ export default [
     n_neutrons: 175,
     n_protons: 114,
     n_electrons: 114,
-    group: 14,
     radioactive: true,
     natural: null,
     metal: true,
@@ -5249,7 +5135,6 @@ export default [
     n_neutrons: 173,
     n_protons: 115,
     n_electrons: 115,
-    group: 15,
     radioactive: true,
     natural: null,
     metal: true,
@@ -5294,7 +5179,6 @@ export default [
     n_neutrons: 176,
     n_protons: 116,
     n_electrons: 116,
-    group: 16,
     radioactive: true,
     natural: null,
     metal: true,
@@ -5339,7 +5223,6 @@ export default [
     n_neutrons: 178,
     n_protons: 117,
     n_electrons: 117,
-    group: 17,
     radioactive: true,
     natural: null,
     metal: null,
@@ -5384,7 +5267,6 @@ export default [
     n_neutrons: 176,
     n_protons: 118,
     n_electrons: 118,
-    group: 18,
     radioactive: true,
     natural: null,
     metal: null,
diff --git a/src/types.ts b/src/types.ts
index 2ccc0c9..02ca78f 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -4,7 +4,7 @@ export type Element = {
   atomic_radius: number
   boiling_point: number | null
   category: string
-  column: number // aka group
+  column: number // aka group, in range 1 - 18
   covalent_radius: number
   density: number
   discoverer: string
@@ -30,7 +30,7 @@ export type Element = {
   nonmetal: boolean | null
   number_of_isotopes: number
   number: number
-  phase: string
+  phase: 'Gas' | 'Liquid' | 'Solid'
   radioactive: boolean | null
   row: number // != period for lanthanides and actinides
   shells: number[]