Pad the empty Team card and space the Settings environment section

The "You are not in a team yet." card was a bare .card, which has no
padding, so the text sat against the border. The "From the environment"
heading follows the settings form in the same card and h3 has no margin,
so it touched the Save button; space it with a rule scoped to a heading
that directly follows .admin-settings.

Claude-Session: https://claude.ai/code/session_016mBLURvJoMuUEr9cB2RpUN

internal/web/static/js/team.js

@@ -139,7 +139,7 @@ function render() {
   if (!data) {
     clear(view(), error
       ? h('div', { class: 'load-error', text: error })
-      : h('div', { class: 'card' }, h('p', { class: 'muted', text: 'You are not in a team yet.' })));
+      : h('div', { class: 'card card-pad' }, h('p', { class: 'muted', text: 'You are not in a team yet.' })));
     return;
   }
   clear(view(),