Consistency audit: shared input/button/heading tokens across pages (#18)

- One text-input treatment (size, color, placeholder) for .search input,
  .pw-field input, #title, #custom, .row text inputs
- Icon-only buttons (.iconbtn, .btn-icon) share .btn radius + focus ring
- Unified heading letter-spacing with .side-section h3 pattern
- Normalized settings card padding to the 12/18px wide-card scale
- Verified visually: before/after screenshots for new/history/settings/unlock

Closes #18

web/static/app.css

@@ -339,8 +339,46 @@ th.sorted.asc .sort-ind { border-bottom: 6px solid var(--accent); }
 th.sorted.desc .sort-ind { border-top: 6px solid var(--accent); }
 
 /* ============================================================
-   Mobile responsiveness (#45) — desktop above is unchanged
+   Consistency audit (#18) — shared tokens across inputs, buttons,
+   headings. Visual-only, no behavior change.
    ============================================================ */
+
+/* shared text-input treatment: .search input, .pw-field input, #title, #custom */
+.search input,
+.pw-field input,
+.editor-head input#title,
+.custom-input,
+.row input[type="text"] {
+  font-size: 21.6px;
+  color: var(--fg);
+}
+.search input::placeholder,
+.pw-field input::placeholder,
+.editor-head input#title::placeholder,
+.custom-input::placeholder {
+  color: var(--muted);
+}
+.custom-input { border-radius: var(--radius); }
+
+/* buttons (incl. icon-only variants) share one radius + focus ring */
+.btn-icon, .iconbtn {
+  border-radius: var(--radius);
+  transition: color .12s ease, border-color .12s ease, background .12s ease;
+}
+.iconbtn:focus-visible, .btn:focus-visible, .btn-icon:focus-visible, .pager button:focus-visible {
+  outline: 2px solid var(--accent);
+  outline-offset: 1px;
+}
+
+/* headings: unified treatment (mirrors .side-section h3) */
+.settings-head h1, .paste-title-bar h1, .head-row h1, .inner h1 {
+  letter-spacing: -0.01em;
+}
+
+/* consistent card padding scale: 12px 18px for wide card heads/bodies */
+.settings-head { padding: 12px 18px; }
+.settings-body { padding: 16px 18px; }
+
 @media (max-width: 640px) {
   body { font-size: 16px; }