Styling

All styling options are passed to useExpressCSV().

Theme

Override CSS variables to match your app's design system. Pass a flat object for a single theme, or use modes to provide separate light and dark values.

Single Theme

Applies to both light and dark mode:

import { useExpressCSV, x, type ECSVTheme } from "@expresscsv/react";

const theme: ECSVTheme = {
  primary: "#4F46E5",
  "primary-foreground": "#ffffff",
  background: "#ffffff",
  foreground: "#0f172a",
  border: "#e5e7eb",
  ring: "#A5B4FC",
  radius: "0.5rem",
};

const { open } = useExpressCSV({
  schema,
  getSessionToken: async () => fetchSessionToken(), // Ask your backend for a short-lived importer session token
  importIdentifier: "user-import", // Ties this config to a specific import flow
  theme, // Applies these design tokens to the importer
});

Dual-Mode Theme

Provide separate values for light and dark:

const theme: ECSVTheme = {
  modes: {
    light: {
      primary: "#4F46E5",
      background: "#ffffff",
      foreground: "#0f172a",
    },
    dark: {
      primary: "#a5b4fc",
      background: "#09090b",
      foreground: "#fafafa",
    },
  },
};

Theme Variables

Variable	Default (light)
`radius`	`0.625rem`
`background`	`oklch(1 0 0)`
`foreground`	`oklch(0.145 0 0)`
`card`	`oklch(1 0 0)`
`card-foreground`	`oklch(0.145 0 0)`
`popover`	`oklch(1 0 0)`
`popover-foreground`	`oklch(0.145 0 0)`
`primary`	`oklch(0.205 0 0)`
`primary-foreground`	`oklch(0.985 0 0)`
`secondary`	`oklch(0.97 0 0)`
`secondary-foreground`	`oklch(0.205 0 0)`
`muted`	`oklch(0.97 0 0)`
`muted-foreground`	`oklch(0.556 0 0)`
`accent`	`oklch(0.7 0.2 145)`
`accent-foreground`	`oklch(0.985 0 0)`
`destructive`	`oklch(0.577 0.245 27.325)`
`destructive-foreground`	`oklch(0.985 0 0)`
`success`	`oklch(0.7 0.2 145)`
`success-foreground`	`oklch(0.985 0 0)`
`warning`	`oklch(0.769 0.188 70)`
`warning-foreground`	`oklch(0.985 0 0)`
`border`	`oklch(0.922 0 0)`
`input`	`oklch(0.922 0 0)`
`ring`	`oklch(0.708 0 0)`
`font-title`	`inherit`
`font-body`	`inherit`

Color Mode

Control light/dark mode with colorMode:

const { open } = useExpressCSV({
  schema,
  getSessionToken: async () => fetchSessionToken(), // Ask your backend for a short-lived importer session token
  importIdentifier: "user-import", // Ties this config to a specific import flow
  colorMode: "system", // Match the user's OS or app color preference
});

Custom CSS

Every element in the importer is stylable. Open your browser inspector and look for ecsv-... class names on the element you want to target.

Class names shown before the 🔒 marker are public and safe to style. Everything after 🔒 is a private implementation detail and may change between versions.

Your customCSS is automatically scoped to the importer, so you can target public classes directly:

const { open } = useExpressCSV({
  schema,
  getSessionToken: async () => fetchSessionToken(), // Ask your backend for a short-lived importer session token
  importIdentifier: "user-import", // Ties this config to a specific import flow
  customCSS: `
    .ecsv-step-upload {
      padding: 1.5rem;
    }

    .ecsv-card {
      border-radius: 1rem;
    }

    .ecsv-button {
      font-weight: 600;
      border-radius: 9999px;
    }
  `,
});

Custom Fonts

Load fonts from Google Fonts or a custom URL, then reference them in your theme:

const { open } = useExpressCSV({
  schema,
  getSessionToken: async () => fetchSessionToken(), // Ask your backend for a short-lived importer session token
  importIdentifier: "user-import", // Ties this config to a specific import flow
  fonts: {
    title: { source: "google", name: "Space Grotesk", weights: [400, 600, 700] }, // Load the heading font from Google Fonts
    body: { source: "custom", url: "https://example.com/font.woff2", format: "woff2" }, // Load your body font from a hosted asset
  },
  theme: {
    "font-title": "'Space Grotesk', sans-serif", // Use the loaded title font in the importer
    "font-body": "'Custom Font', sans-serif", // Use the loaded body font in the importer
  },
});

Step Display

Control how the wizard progress indicator looks:

const { open } = useExpressCSV({
  schema,
  getSessionToken: async () => fetchSessionToken(), // Ask your backend for a short-lived importer session token
  importIdentifier: "user-import", // Ties this config to a specific import flow
  stepDisplay: "segmented", // Show progress as labeled steps instead of a bar
});

On this page