.compose-form__modifiers {
color: #fff;
font-family: inherit;
font-size: 14px;
background: #282c37;
}
.composer--options-wrapper {
padding: 10px;
background: #1f232b;
border-radius: 0 0 4px 4px;
height: 27px;
display: flex;
justify-content: space-between;
flex: 0 0 auto;
}
.autosuggest-input label .autosuggest-textarea_textarea, .compose-formautosuggest-wrapper label .autosuggest-textarea_textarea {
display: block;
box-sizing: border-box;
margin: 0;
border: 0;
border-radius: 4px 4px 0 0;
padding: 10px 32px 10px 10px;
width: 100%;
min-height: 100px;
outline: 0;
color: #fff;
background: #282c37;
font-size: 14px;
font-family: inherit;
resize: none;
scrollbar-color: auto;
}
.character-counter {
cursor: default;
font-family: "mastodon-font-sans-serif",sans-serif;
font-size: 14px;
font-weight: 600;
color: #FFF;
}
.autosuggest-input label .autosuggest-textarea_textarea:disabled, .compose-formautosuggest-wrapper label .autosuggest-textarea_textarea:disabled {
background: #282c37;
}
you can prolly trim out the parts that don't directly modify the colors, but this should be it

se escribe : blobaww : sin espacio.