I am in the Etch testing group, and I love the neon green Etch UI color, so I applied it to Bricks v2 Beta. I chose the beta because it is already significantly better than V1, so the necessary changes are minimal.

This has been updated with the new version 2 and the changes in Advanced Themer. Etch has moved on from the bright green, but I have stuck with it for now. Shout out to James Lively for the reminder to add the modification indicator.

Screenshot of the builder with styling applied
:root {
    --etch-green:212, 235, 94;
    --builder-color-accent: rgba(var(--etch-green), 1);
    --builder-bg-accent: #D5EC5E50;
    --builder-color: #fff !important;
}
/* Move the CSS Panel to the Top */
.control-groups {
    display: flex;
    flex-direction: column;
}
.category-title,
body.at-has-shortcuts-sidebar
    #bricks-structure
    .brxce-panel-shortcut__wrapper
    i {
    opacity: 0.7 !important;
}
[data-control-group="_css"] {
    order: -1;
    margin-block-end: 6px;
}
/* make space for tooltip above the AT structure search */
#bricks-structure #bricks-panel-header{
    z-index: 2;
}
li.has-settings {
 background-color: rgba(var(--etch-green), .5) !important;
}
span.bricks-svg-wrapper::after {
display: none !important;
}
span.bricks-svg-wrapper::after {
display: none !important;
}
#bricks-structure .structure-item:hover .actions .action {
    opacity:.75;
}
#bricks-structure .element.active>.structure-item{
    color: var(--builder-color);
}
.bricks-panel *:not(.brxc-tag-btn){
    font-size: 14px!important;
}
#bricks-panel-tabs li.active,
#bricks-toolbar .logo {
    background-color: var(--builder-color-accent);
    color: #000;
}