---
title: "Theming: Customising Headers"
framework: vue
version: "36.1.0"
---

# Theming: Customising Headers

Style grid header cells and column groups.

The grid exposes many theme parameters starting `header*` for customising header appearance:

```js
const myTheme = themeQuartz.withParams({
    headerHeight: '30px',
    headerTextColor: 'white',
    headerBackgroundColor: 'black',
    headerCellHoverBackgroundColor: 'rgba(80, 40, 140, 0.66)',
    headerCellMovingBackgroundColor: 'rgb(80, 40, 140)',
});
```

For the full list, see the [Headers section](https://www.ag-grid.com/vue-data-grid/theming-api/#reference-headers) of the parameters reference.

When the theme parameters are not enough you can use CSS classes, in particular `ag-header`, `ag-header-cell`, and `ag-header-group-cell`:

```css
.ag-header {
    font-family: cursive;
}
.ag-header-group-cell {
    font-weight: normal;
    font-size: 22px;
}
.ag-header-cell {
    font-size: 18px;
}
```

#### Colour Customisation

```ts
import {
  createApp,
  defineComponent,
  onBeforeMount,
  ref,
  shallowRef,
} from "vue";
import { AgGridVue } from "ag-grid-vue3";
import "./styles.css";
import {
  ColDef,
  ColGroupDef,
  GridApi,
  GridOptions,
  GridReadyEvent,
  ModuleRegistry,
  Theme,
  enableDevValidations,
  themeQuartz,
} from "ag-grid-community";
import { AllEnterpriseModule } from "ag-grid-enterprise";
import { IOlympicData } from "./interfaces";
if (process.env.NODE_ENV !== "production") {
  enableDevValidations();
}

ModuleRegistry.registerModules([AllEnterpriseModule]);

const myTheme = themeQuartz.withParams({
  headerHeight: "30px",
  headerTextColor: "white",
  headerBackgroundColor: "black",
  headerCellHoverBackgroundColor: "rgba(80, 40, 140, 0.66)",
  headerCellMovingBackgroundColor: "rgb(80, 40, 140)",
});

const VueExample = defineComponent({
  template: `
        <div style="height: 100%">
                <ag-grid-vue
      style="width: 100%; height: 100%;"
      @grid-ready="onGridReady"
      :theme="theme"
      :columnDefs="columnDefs"
      :defaultColDef="defaultColDef"
      :rowData="rowData"></ag-grid-vue>
        </div>
    `,
  components: {
    "ag-grid-vue": AgGridVue,
  },
  setup(props) {
    const gridApi = shallowRef<GridApi<IOlympicData> | null>(null);
    const theme = ref<Theme | "legacy">(myTheme);
    const columnDefs = ref<(ColDef | ColGroupDef)[]>([
      {
        headerName: "Group 1",
        children: [{ field: "athlete", minWidth: 170 }, { field: "age" }],
      },
      {
        headerName: "Group 2",
        children: [
          { field: "country" },
          { field: "year" },
          { field: "date" },
          { field: "sport" },
          { field: "gold" },
          { field: "silver" },
          { field: "bronze" },
          { field: "total" },
        ],
      },
    ]);
    const defaultColDef = ref<ColDef>({
      editable: true,
      filter: true,
    });
    const rowData = ref<IOlympicData[]>(null);

    const onGridReady = (params: GridReadyEvent) => {
      gridApi.value = params.api;

      const updateData = (data) => (rowData.value = data);

      fetch("https://www.ag-grid.com/example-assets/olympic-winners.json")
        .then((resp) => resp.json())
        .then((data) => updateData(data));
    };

    return {
      gridApi,
      theme,
      columnDefs,
      defaultColDef,
      rowData,
      onGridReady,
    };
  },
});

const app = createApp(VueExample);
app.mount("#app");
```

[Live example: Colour Customisation](https://www.ag-grid.com/examples/theming-headers/header-customisation/vue3)

## Header Column Borders and Resize Handles

Header Column Borders appear between every column, whereas Resize Handles only appear on resizeable columns (Group 1 in the example below).

```js
const myTheme = themeQuartz.withParams({
    headerColumnBorder: { color: 'purple' },
    headerColumnBorderHeight: '80%',

    headerColumnResizeHandleColor: 'orange',
    headerColumnResizeHandleHeight: '25%',
    headerColumnResizeHandleWidth: '5px',
});
```

#### Column Separators

```ts
import {
  createApp,
  defineComponent,
  onBeforeMount,
  ref,
  shallowRef,
} from "vue";
import { AgGridVue } from "ag-grid-vue3";
import {
  ColDef,
  ColGroupDef,
  GridApi,
  GridOptions,
  GridReadyEvent,
  ModuleRegistry,
  Theme,
  enableDevValidations,
  themeQuartz,
} from "ag-grid-community";
import { AllEnterpriseModule } from "ag-grid-enterprise";
import { IOlympicData } from "./interfaces";
if (process.env.NODE_ENV !== "production") {
  enableDevValidations();
}

ModuleRegistry.registerModules([AllEnterpriseModule]);

const myTheme = themeQuartz.withParams({
  headerColumnBorder: { color: "purple" },
  headerColumnBorderHeight: "80%",
  headerColumnResizeHandleColor: "orange",
  headerColumnResizeHandleHeight: "25%",
  headerColumnResizeHandleWidth: "5px",
});

const VueExample = defineComponent({
  template: `
        <div style="height: 100%">
                <ag-grid-vue
      style="width: 100%; height: 100%;"
      @grid-ready="onGridReady"
      :theme="theme"
      :columnDefs="columnDefs"
      :defaultColDef="defaultColDef"
      :rowData="rowData"></ag-grid-vue>
        </div>
    `,
  components: {
    "ag-grid-vue": AgGridVue,
  },
  setup(props) {
    const gridApi = shallowRef<GridApi<IOlympicData> | null>(null);
    const theme = ref<Theme | "legacy">(myTheme);
    const columnDefs = ref<(ColDef | ColGroupDef)[]>([
      {
        headerName: "Group 1",
        children: [
          { field: "athlete", minWidth: 170, resizable: true },
          { field: "age", resizable: true },
        ],
        resizable: true,
      },
      {
        headerName: "Group 2",
        children: [
          { field: "country" },
          { field: "year" },
          { field: "date" },
          { field: "sport" },
          { field: "gold" },
          { field: "silver" },
          { field: "bronze" },
          { field: "total" },
        ],
      },
    ]);
    const defaultColDef = ref<ColDef>({
      editable: true,
      filter: true,
      resizable: false,
    });
    const rowData = ref<IOlympicData[]>(null);

    const onGridReady = (params: GridReadyEvent) => {
      gridApi.value = params.api;

      const updateData = (data) => (rowData.value = data);

      fetch("https://www.ag-grid.com/example-assets/olympic-winners.json")
        .then((resp) => resp.json())
        .then((data) => updateData(data));
    };

    return {
      gridApi,
      theme,
      columnDefs,
      defaultColDef,
      rowData,
      onGridReady,
    };
  },
});

const app = createApp(VueExample);
app.mount("#app");
```

[Live example: Column Separators](https://www.ag-grid.com/examples/theming-headers/header-customisation-columns/vue3)

## Style Header on Filter

Each time a [Column Filter](https://www.ag-grid.com/vue-data-grid/filtering/) is applied to a column, the CSS class `ag-header-cell-filtered` is added to the header. This can be used for adding style to headers that are filtered.

The example below adds some styling to `ag-header-cell-filtered`, so when you filter a column you will notice the column header change.

#### Style Header

```ts
import {
  createApp,
  defineComponent,
  onBeforeMount,
  ref,
  shallowRef,
} from "vue";
import { AgGridVue } from "ag-grid-vue3";
import "./styles.css";
import {
  AllCommunityModule,
  ColDef,
  ColGroupDef,
  GridApi,
  GridOptions,
  GridReadyEvent,
  GridState,
  ModuleRegistry,
  enableDevValidations,
} from "ag-grid-community";
import { IOlympicData } from "./interfaces";
if (process.env.NODE_ENV !== "production") {
  enableDevValidations();
}

ModuleRegistry.registerModules([AllCommunityModule]);

const VueExample = defineComponent({
  template: `
        <div style="height: 100%">
                <ag-grid-vue
      style="width: 100%; height: 100%;"
      @grid-ready="onGridReady"
      :columnDefs="columnDefs"
      :defaultColDef="defaultColDef"
      :initialState="initialState"
      :rowData="rowData"></ag-grid-vue>
        </div>
    `,
  components: {
    "ag-grid-vue": AgGridVue,
  },
  setup(props) {
    const gridApi = shallowRef<GridApi<IOlympicData> | null>(null);
    const columnDefs = ref<ColDef[]>([
      { field: "athlete" },
      { field: "age", maxWidth: 120 },
      { field: "country" },
      { field: "year", maxWidth: 120 },
      { field: "sport" },
      { field: "gold" },
      { field: "silver" },
      { field: "bronze" },
      { field: "total" },
    ]);
    const defaultColDef = ref<ColDef>({
      flex: 1,
      minWidth: 150,
      filter: true,
    });
    const initialState = ref<GridState>({
      filter: {
        filterModel: {
          country: {
            filterType: "text",
            type: "contains",
            filter: "us",
          },
        },
      },
    });
    const rowData = ref<IOlympicData[]>(null);

    const onGridReady = (params: GridReadyEvent) => {
      gridApi.value = params.api;

      const updateData = (data) => (rowData.value = data);

      fetch("https://www.ag-grid.com/example-assets/olympic-winners.json")
        .then((resp) => resp.json())
        .then((data) => updateData(data));
    };

    return {
      gridApi,
      columnDefs,
      defaultColDef,
      initialState,
      rowData,
      onGridReady,
    };
  },
});

const app = createApp(VueExample);
app.mount("#app");
```

[Live example: Style Header](https://www.ag-grid.com/examples/theming-headers/style-header-on-filter/vue3)

## Styling the First and Last Columns

You can style all first and last column headers (Grouped, Non-Grouped and Floating Filters) using CSS by targeting the `.ag-column-first` and `.ag-column-last` selectors as follows:

```css
.ag-header-group-cell.ag-column-first {
    background-color: #2244cc66; /* bluest */
}
.ag-header-cell.ag-column-first {
    background-color: #2244cc44; /* bluer */
}
.ag-floating-filter.ag-column-first {
    background-color: #2244cc22; /* blue */
}

.ag-header-group-cell.ag-column-last {
    background-color: #33cc3366; /* greenest */
}
.ag-header-cell.ag-column-last {
    background-color: #33cc3344; /* greener */
}
.ag-floating-filter.ag-column-last {
    background-color: #33cc3322; /* green */
}
```

#### Style Header

```ts
import {
  createApp,
  defineComponent,
  onBeforeMount,
  ref,
  shallowRef,
} from "vue";
import { AgGridVue } from "ag-grid-vue3";
import "./styles.css";
import {
  AllCommunityModule,
  ColDef,
  ColGroupDef,
  GridApi,
  GridOptions,
  GridReadyEvent,
  ModuleRegistry,
  enableDevValidations,
} from "ag-grid-community";
import { IOlympicData } from "./interfaces";
if (process.env.NODE_ENV !== "production") {
  enableDevValidations();
}

ModuleRegistry.registerModules([AllCommunityModule]);

const VueExample = defineComponent({
  template: `
        <div style="height: 100%">
                <ag-grid-vue
      style="width: 100%; height: 100%;"
      @grid-ready="onGridReady"
      :columnDefs="columnDefs"
      :defaultColDef="defaultColDef"
      :rowData="rowData"></ag-grid-vue>
        </div>
    `,
  components: {
    "ag-grid-vue": AgGridVue,
  },
  setup(props) {
    const gridApi = shallowRef<GridApi<IOlympicData> | null>(null);
    const columnDefs = ref<(ColDef | ColGroupDef)[]>([
      {
        headerName: "Athlete Details",
        children: [
          { field: "athlete" },
          { field: "age", maxWidth: 120 },
          { field: "country" },
        ],
      },
      { field: "year", maxWidth: 100 },
      {
        headerName: "Sport Details",
        children: [
          { field: "total", columnGroupShow: "closed" },
          { field: "gold", columnGroupShow: "open" },
          { field: "silver", columnGroupShow: "open" },
          { field: "bronze", columnGroupShow: "open" },
        ],
      },
    ]);
    const defaultColDef = ref<ColDef>({
      flex: 1,
      minWidth: 150,
      filter: true,
      floatingFilter: true,
    });
    const rowData = ref<IOlympicData[]>(null);

    const onGridReady = (params: GridReadyEvent) => {
      gridApi.value = params.api;

      const updateData = (data) => (rowData.value = data);

      fetch("https://www.ag-grid.com/example-assets/olympic-winners.json")
        .then((resp) => resp.json())
        .then((data) => updateData(data));
    };

    return {
      gridApi,
      columnDefs,
      defaultColDef,
      rowData,
      onGridReady,
    };
  },
});

const app = createApp(VueExample);
app.mount("#app");
```

[Live example: Style Header](https://www.ag-grid.com/examples/theming-headers/style-header-first-last/vue3)