css: .row style guide + conditional templates — fix 'log out' breaking + note overlap

The previous .row rule unconditionally pinned column 2 at 1fr, which
stretched whichever child happened to land there. On the screenshot
that meant the 'log out' button got stretched and wrapped its label
across two lines, and the trailing note overlapped buttons it was
supposed to describe.

New rules (now also documented in CLAUDE.md as a style guide so future
authoring is consistent):

- default .row: grid-auto-columns: max-content (everything packs at
  its natural width, no stretch)
- :has(> :first-child + input/select): template 'auto 1fr', input grows
- :has(> input/select:first-child): template '1fr', input fills, rest pack
- .row > .note: auto-drops to its own line under the buttons/inputs via
  grid-column: 1 / -1
- .row > label: white-space: normal, so long checkbox labels wrap

Applied to zebra-spaces, chat, zebra-audio. CLAUDE.md "Web style
guide — form-row patterns" table lists every supported shape so new
rows reuse the primitive instead of inventing custom layouts.

web/zebra-spaces.html

@@ -298,19 +298,40 @@
   button.invert { background: #000; color: #fff; }
   button.invert:hover:not(:disabled) { background: #333; }
   button.small { padding: 0.2rem 0.55rem; font-size: 0.75rem; }
-  /* form rows: inline strip with a single grow track for the input/select.
-   * grid-template-columns is generous enough for the common shapes:
-   *   label input            (1) label-stretchy
-   *   label input button     (2) label-stretchy-button
-   *   button button span     (3) buttons-stretchy
-   * Items past the third just flow into the row via grid-auto-flow. */
+  /* form-row style guide — every form row is a grid.
+   *   default                children pack at max-content width, no stretch
+   *   <something> <input/select> ...  → template "auto 1fr ..." so the
+   *                                      input cell grows
+   *   <input/select> ...     → template "1fr ..." so the field fills,
+   *                            packed siblings follow
+   *   any <span.note> child  → moved to its own row inside the grid so
+   *                            long text never competes with the
+   *                            buttons it explains
+   * Items beyond the templated cells flow via grid-auto-columns:max-content. */
   .row {
     display: grid;
     grid-auto-flow: column;
-    grid-template-columns: max-content minmax(0, 1fr);
     grid-auto-columns: max-content;
     align-items: center; gap: 0.6rem; margin-bottom: 0.6rem;
   }
+  .row:has(> :first-child + input[type=text]),
+  .row:has(> :first-child + input[type=password]),
+  .row:has(> :first-child + select) {
+    grid-template-columns: max-content minmax(0, 1fr);
+  }
+  .row:has(> input[type=text]:first-child),
+  .row:has(> input[type=password]:first-child),
+  .row:has(> select:first-child) {
+    grid-template-columns: minmax(0, 1fr);
+  }
+  /* notes inside a row drop to their own line under the buttons/inputs
+   * instead of fighting them for horizontal space */
+  .row > .note {
+    grid-column: 1 / -1;
+    margin-top: 0.05rem; line-height: 1.4;
+  }
+  /* labels wrapping a checkbox + long text break naturally */
+  .row > label { white-space: normal; }
   input[type=text], input[type=password] {
     font-family: monospace; font-size: 0.9rem; border: 1px solid #000;
     padding: 0.4rem; background: #fff; color: #000; min-width: 0; width: 100%;
@@ -2301,8 +2322,8 @@ logLine('', 'ready — pick a handle, type a rendezvous code, enter the space');
 
 <footer style="margin:2.2rem auto 0;font-size:0.65rem;color:#999;line-height:1.7;word-break:break-all;font-family:monospace">
   <span id="pi-seal" style="color:#777;cursor:default;user-select:none" title="">page integrity</span> &nbsp;·&nbsp; built <span class="stamp-date">2026-06-02</span><br>
-  md5 <span class="stamp-md5">ddf174a681416af767243cb652f4c946</span><br>
-  sha256 <span class="stamp-sha">3c1db79787ea6e2c0cac7ea75e20bb59dc2d9c47f628b4964d65af58fa1f415f</span><br>
+  md5 <span class="stamp-md5">d43eccee30cc6f4a999e3af6806138d2</span><br>
+  sha256 <span class="stamp-sha">4b481a70ef4564ed9950982d9a61d2cabd7860d1ae79f6db6caa73f443bfef2d</span><br>
   <span style="color:#bbb">hashes are of this page with these two fields zeroed — to verify, blank them and re-hash</span><br>
   <span style="color:#bbb">one self-contained file — <strong>save a copy</strong> and verify against these hashes; point at your own servers with ?signal= and ?turncred=, or <a href="host-your-own.html" style="color:#999">host your own community</a></span>
 </footer>