CSS

38 files, and the language that carries the estate's alignment discipline further than any other. Everything below was reconstructed by counting: there is not one documented CSS rule anywhere.

1. The complete example

:host { display: flex; flex-direction: column; height: 100%; overflow: hidden; }
[hidden] { display: none !important; }

.left-nav {
    display:        flex;
    flex-direction: column;
    align-items:    stretch;
    padding:        6px 0;
    height:         100%;
    background:     var(--bg-panel);
    border-right:   1px solid var(--border-1);
    gap:            2px;
}

.nav-item {
    display:         flex;
    flex-direction:  column;
    align-items:     center;
    justify-content: center;
    gap:             3px;
    padding:         10px 0;
    background:      transparent;

2. Alignment, per block

Property values are aligned to a column within each rule — exactly the discipline applied to Python attribute annotations and JavaScript object keys. In the example above, .left-nav and .nav-item align at different columns, each set by its own longest property name.

The unit of alignment is the block, not the file.

That detail is what makes the convention survivable. If the column were file-wide, adding one long property name anywhere would reformat the whole file and produce a diff nobody can read. Per-block, the blast radius of a rename is the block you were editing anyway.

The argument for doing this at all — that it is a machine-readability decision rather than an aesthetic one, in a codebase 61% written by an agent — is made in full on the house style page, along with the honest note that it is a claim rather than a measured finding. No formatter in the industry will produce this, so adopting it means never adopting prettier. That is a real and permanent cost. Q1 →

3. The other conventions in that file

• :host first, as a single line, establishing the component's own box.
• [hidden] { display: none !important; } as a standing reset. The !important is deliberate: display: flex on :host would otherwise beat the attribute, and a hidden component would render.
• Flexbox for layout, with gap rather than margins.
• Every colour and surface is a token. No literal hex values in component CSS, ever.
• Class names are plain and semantic — .left-nav, .nav-item, .nav-icon. Not BEM, not utility classes.

Why not BEM

BEM exists to solve a problem shadow DOM removes.

BEM, utility classes and every other naming scheme that encodes structure into a class name exist because global stylesheets leak. Inside a shadow root the styles cannot leak, so they do not need namespacing, and a naming convention that fights the cascade is a cost you only pay if your styles are global. Dropping it is not sloppiness — it is declining to pay for a problem you no longer have.

4. Design tokens

Tokens come from the versioned CDN and are adopted per component:

get sharedCssPaths() { return ['https://dev.tools.sgraph.ai/components/tokens/v1/v1.0/v1.0.0/sg-tokens.css'] }

Two things about the token system are worth copying, and one is worth fixing.

The good part: bounded numbered ramps. --text-1 through --text-4, --sg-sp-1 through --sg-sp-4, --shadow-1 and --shadow-2. A bounded ramp rather than arbitrary values means there is a right answer to “which grey?” and a small number of wrong ones. This site's own stylesheet uses the same shape.

The part to fix: three prefixes for one token system.

Pick one prefix, or document what each family means. Either is fine; having three and no explanation is not. Q3 →

5. Theming

The token indirection is what makes theming possible at all: components reference var(--bg-panel) and never a literal, so a theme is a different sg-tokens.css at a different version path.

6. The one rule that would catch defects

Formatting rules are cheap and mostly cosmetic. There is one CSS rule here that would catch real bugs: no literal colours outside the token file. A single hard-coded #fff in a component stylesheet is invisible in review, survives every refactor, and breaks the day somebody ships a second theme. The stylelint config →