Bobby Vault — email logo usage (brand version 1.2.0)

Production default: PNG. Reference every image with an absolute URL under
https://bobbyvault.com/images/email/ — never a relative path or an inline SVG,
because most email clients block or fail to render SVG.

Header ....... 240x53 CSS px, @2x source 480x106
Footer ....... 160x36 CSS px, @2x source 320x71
Icon ......... 48x48 CSS px, @2x source 96x96
Monochrome ... bobby-vault-email-mono*.png for one-colour and plain-text-style mail

Filled-background files (-light / -dark) are safe everywhere and are the default.
Transparent files (-transparent-darkink / -transparent-lightink) are for clients
whose background is known; pair them with a <picture> or prefers-color-scheme
block and always set an opaque fallback.

Dark-mode fallback: default to the light-surface asset and swap to the dark-surface
asset with @media (prefers-color-scheme: dark). Clients that ignore the media query
keep a legible logo either way.

Alt text: "Bobby Vault" for lockups, "Bobby Vault logo" for the beeldmerk icon.
Always set explicit width and height attributes.
