Onboarding: paste-a-spec door, workspace-import and learn links

src/app/components/Onboarding.module.css

@@ -37,6 +37,79 @@
 
 /* The two CTAs and the per-example Adds are shared Buttons (arch 09 §4). */
 
+/* Paste-a-spec disclosure panel: revealed below the doors, form-shaped
+   (label above field, hint between — GOV.UK textarea). */
+.pastePanel {
+  margin-top: var(--space-4);
+  padding: var(--space-4);
+  border: var(--border-width) solid var(--border);
+  border-radius: var(--radius);
+  background: var(--layer-01);
+  /* Elevated surface: the textarea's field fill steps off --layer-01 (arch 09 §4). */
+  --field: var(--field-02);
+  --field-hover: var(--field-hover-02);
+}
+
+.pasteLabel {
+  display: block;
+  margin-bottom: var(--space-1);
+  font-size: 14px;
+  font-weight: 600;
+}
+
+.pasteHint {
+  margin: 0 0 var(--space-3);
+  font-size: 13px;
+  color: var(--text-secondary);
+  line-height: 1.4;
+}
+
+/* The field look (fill, underline, focus ring) comes from the base.css element
+   baseline; the module adds only sizing idiosyncrasies (arch 09 §4). */
+.pasteInput {
+  display: block;
+  width: 100%;
+  resize: vertical;
+  padding: var(--space-2) var(--space-3);
+  font-family: var(--font-mono);
+  font-size: 12px;
+  line-height: 1.5;
+}
+
+.pasteActions {
+  display: flex;
+  gap: var(--space-3);
+  margin-top: var(--space-3);
+}
+
+/* Secondary paths (import / learn) as one quiet line of links below the doors. */
+.altPaths {
+  margin: var(--space-4) 0 0;
+  font-size: 13px;
+  color: var(--text-secondary);
+}
+
+/* Inline link styling shared by the import action (a button semantically —
+   it triggers the file picker) and the learn anchor. Focus ring comes from the
+   base.css baseline.
+   TODO: this accent-link recipe now exists in four modules (AboutModal .link,
+   DonateModal .email, DatasetsModal .linkButton, here) — past the "third site"
+   threshold AboutModal.module.css records for promoting it to a shared
+   primitive; consolidate into one home (arch 09 §4's four mechanisms). */
+.linkButton {
+  padding: 0;
+  border: none;
+  background: none;
+  font: inherit;
+  color: var(--accent);
+  text-decoration: underline;
+  cursor: pointer;
+}
+
+.hiddenInput {
+  display: none;
+}
+
 /* The "or start from an example" header row, with Add all pushed to the end. */
 .galleryHead {
   display: flex;