How do I use the new design settings?

The composer gives you two layers of design control: newsletter-wide defaults in the Styles tab, and per-block settings that override those defaults (including any custom CSS). This guide covers both. For everything else the composer can do, see Working in Emails.

Newsletter-wide defaults (Styles tab)

Open your newsletter and select Styles to set defaults that apply to all new blocks:

• Desktop width and Mobile width for the email.
• Default Block, Divider, Text, and Image styles — including default text formatting, image alignment, divider style, and button style. The Text styles can also switch on decorative lines for each heading size.

Note: the mobile breakpoint (max mobile width, default 350px) can affect how promotions render — beyond 800px, a two-column promotion may shift to a top-bottom layout depending on screen size.

Shared styling controls

Most blocks share the same customization tools:

• Colors — clicking any color swatch opens a palette and color picker; you can enter values as RGB, HSL, or HEX, and save colors for reuse. Saved colors apply to all blocks where color can be used.
• Borders — color, thickness, and style.
• Fonts — type, size, and style. A fallback font is used when an email client doesn’t support your primary font.
• Padding — apply one value to all sides or set each side individually.

Per-block options

Button — link the button to a URL; adjust button color, text color, alignment, border radius, border, background, and font.

Blockquote — set the left border color, plus borders, background, text color, font, and padding.

Divider — adjust the divider’s color, thickness, and style, plus border, background, and padding.

Heading and Paragraph — pick a heading type (H1–H6) and font size; use the Customize your block settings for borders, font type and size, alignment, background and text colors, and padding. See How to customize your newsletter using Heading and Paragraph blocks.

HTML — enter your own markup. See How can I use HTML in Letterhead?

Image — choose or replace an image, add a link for clicks, add alt text, set alignment, and style the border, background, and padding.

Social Profiles — enter your profile URLs, drag to reorder, show names or icons, recolor the icons, and set alignment, border, background, and padding. See How can I include my social profile as part of my newsletter?

Social Share — pick which share options to enable, drag to reorder, display text or icons only, and adjust alignment, border, font, colors, and padding. See How can my audience members easily share my newsletter?

YouTube — add a video URL, set a thumbnail with a play-button overlay, and adjust alignment, width, border, and background. See How to Add a YouTube Video to Your Newsletter.

Curation — search your curated content by keyword, filter by source or tag, pick a layout, and load items; then choose how to display the title, excerpt, date, source, and author, and style the font and colors. See How can I add curated content to my newsletter?

Blocks sitting side by side

Some emails — usually ones you started from a template — have a section that places two blocks next to each other, like an image beside a headline and a button. The pieces inside work like any other block:

• Click the piece you want to change — an image, heading, paragraph, button, or divider — and its settings open on the right, the same ones you’d get anywhere else in your email.
• Copy and delete apply to the piece you picked, not the whole section. A copy lands directly below it, on the same side.
• The two sides are independent. Change a color, font, or padding on one and the other is left exactly as it was.
• Borders belong to the section as a whole, so set those on the section rather than on the pieces inside it.
• On a phone the two sides stack, one above the other, so neither gets squeezed narrow.

Selecting a piece also brings up the section’s own controls, so you can still move or remove the whole section from there.

Mobile-specific styling

For mobile font sizes and padding on individual blocks, see How to Adjust Mobile Font Size and Padding in Letterhead.