WCAG success criterion: "A contrast ratio of at least 3:1 to adjacent Colors applies to the visual presentation of:

1. User interface components: Visual information that can be used to identification of user interface components and states, except for inactive components or when the appearance of the component is determined by the user agent and is not changed by the author;
2. Graphical objects: Portions of graphics that are required to understand the content unless a particular presentation of graphics is indispensable for the content to be conveyed”

People with visual impairments depend on the fact that graphic control elements and information-carrying elements stand out from the background with sufficient contrast.
The frame marked in red, the input field marked in yellow and the underscore marked in blue do not stand out sufficiently from the background with a contrast ratio of 1.3:1 and 1.1:1, respectively, they do not stand out sufficiently from the background (default: at least 3:1). In particularNusers, in particular, find it difficult to recognize the input fields.