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+# Responsive WebUI on Phone Viewports — Implementation Plan
+
+> **Parent spec:** Gitea issue #10 ("Make the server WebUI usable on
+> phone viewports") — verified root causes + acceptance criteria.
+> No separate spec file; the issue body is the spec.
+>
+> **For agentic workers:** REQUIRED SUB-SKILL: use the `implement`
+> skill to run this plan. Steps use `- [ ]` checkboxes for tracking.
+
+**Goal:** Make the server-rendered pages readable and operable on a
+~390px phone viewport without changing the desktop (>=900px) layout.
+
+**Architecture:** CSS-only. Each of the four page templates owns its
+own `<head>`/`<style>` (askama uses `{% import %}`/`{% include %}`, no
+shared base layout). Fix = (1) add a `width=device-width` viewport meta
+tag to every page, (2) append a single `@media (max-width: 640px)`
+block to the three desktop-width pages that overrides only the
+problematic rules. A `max-width` query never matches >=900px, so the
+desktop render is byte-identical. Templates are compile-time embedded
+by askama, so a `cargo build`/`cargo test` of the `server` crate is
+required for edits to take effect.
+
+**Tech Stack:** askama 0.12 templates under `server/templates/`, axum
+routes, existing `server/tests/common` HTTP integration-test harness.
+
+---
+
+## Files this plan creates or modifies
+
+- Create: `server/tests/responsive_test.rs` — regression pins: every
+  page ships the viewport meta; the three desktop-width pages ship an
+  `@media` breakpoint.
+- Modify: `server/templates/login.html:4` — viewport meta only.
+- Modify: `server/templates/my_cases.html:6,78` — viewport meta +
+  `@media` block.
+- Modify: `server/templates/case_recordings.html:5,113` — viewport meta
+  + `@media` block.
+- Modify: `server/templates/case_page.html:6,350` — viewport meta +
+  `@media` block.
+
+---
+
+## Notes on scope boundary
+
+The automated tests below pin the two *textual* acceptance criteria
+(viewport meta present; `@media` breakpoint present). The remaining
+criteria — readable/operable at 390px, vertical reflow of rows/bars,
+~44px touch targets — are visual and cannot be unit-tested without a
+headless browser. They are covered by the CSS in Tasks 3-5 and must be
+confirmed by eye in a narrow viewport (a `fieldtest` / manual pass at
+~390px). This boundary is deliberate, not a coverage gap to "fix" by
+adding a browser-automation dependency.
+
+---
+
+## Task 1: Regression test — RED
+
+**Files:**
+- Create: `server/tests/responsive_test.rs`
+
+- [ ] **Step 1: Write the failing test**
+
+Create `server/tests/responsive_test.rs` with exactly:
+
+```rust
+//! Responsive WebUI regression pins for issue #10.
+//!
+//! These guard the two *textual* acceptance criteria that survive
+//! without a headless browser: every page ships a `width=device-width`
+//! viewport meta tag, and the three desktop-width pages (cases list,
+//! case page, recordings) carry at least one `@media` breakpoint so the
+//! layout can reflow on narrow viewports. The visual criteria (operable
+//! at 390px, 44px touch targets) are verified by eye; these tests stop a
+//! future template rewrite from silently dropping the viewport tag or
+//! the breakpoints.
+
+mod common;
+
+use axum::body::Body;
+use axum::http::{Request, StatusCode};
+use tower::util::ServiceExt;
+
+use common::{TestConfig, body_string, get_with_cookie, paths, seed_case, test_user};
+
+const VIEWPORT: &str = "width=device-width";
+
+#[tokio::test]
+async fn login_page_has_viewport_meta() {
+    let cfg = TestConfig::new()
+        .with_label("resp-login")
+        .with_user(test_user("dr_a"))
+        .build();
+    let app = doctate_server::create_router(cfg);
+
+    let resp = app
+        .oneshot(
+            Request::builder()
+                .uri(paths::LOGIN)
+                .body(Body::empty())
+                .unwrap(),
+        )
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = body_string(resp).await;
+    assert!(body.contains(VIEWPORT), "login page missing viewport meta");
+}
+
+#[tokio::test]
+async fn cases_list_has_viewport_and_media_query() {
+    let cfg = TestConfig::new()
+        .with_label("resp-cases")
+        .with_user(test_user("dr_a"))
+        .build();
+    let app = doctate_server::create_router(cfg);
+    let cookie = common::login(&app, "dr_a", "s").await;
+
+    let resp = app
+        .oneshot(get_with_cookie(paths::CASES, &cookie))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = body_string(resp).await;
+    assert!(body.contains(VIEWPORT), "cases list missing viewport meta");
+    assert!(
+        body.contains("@media"),
+        "cases list missing @media breakpoint"
+    );
+}
+
+#[tokio::test]
+async fn case_page_has_viewport_and_media_query() {
+    let cfg = TestConfig::new()
+        .with_label("resp-cp")
+        .with_user(test_user("dr_a"))
+        .with_llm("http://unused")
+        .build();
+    let case_id = "22222222-2222-2222-2222-222222222222";
+    seed_case(&cfg.data_path, "dr_a", case_id);
+    let app = doctate_server::create_router(cfg);
+    let cookie = common::login(&app, "dr_a", "s").await;
+
+    let resp = app
+        .oneshot(get_with_cookie(paths::case_detail(case_id), &cookie))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = body_string(resp).await;
+    assert!(body.contains(VIEWPORT), "case page missing viewport meta");
+    assert!(
+        body.contains("@media"),
+        "case page missing @media breakpoint"
+    );
+}
+
+#[tokio::test]
+async fn case_recordings_has_viewport_and_media_query() {
+    let cfg = TestConfig::new()
+        .with_label("resp-rec")
+        .with_user(test_user("dr_a"))
+        .build();
+    let case_id = "33333333-3333-3333-3333-333333333333";
+    seed_case(&cfg.data_path, "dr_a", case_id);
+    let app = doctate_server::create_router(cfg);
+    let cookie = common::login(&app, "dr_a", "s").await;
+
+    let resp = app
+        .oneshot(get_with_cookie(paths::case_recordings(case_id), &cookie))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = body_string(resp).await;
+    assert!(
+        body.contains(VIEWPORT),
+        "recordings page missing viewport meta"
+    );
+    assert!(
+        body.contains("@media"),
+        "recordings page missing @media breakpoint"
+    );
+}
+```
+
+- [ ] **Step 2: Run the test to verify it fails**
+
+Run: `cargo test -p doctate-server --test responsive_test -j 4`
+Expected: FAIL — `login page missing viewport meta` (and the three
+`@media` assertions) panic, because no template carries a viewport tag
+or `@media` yet.
+
+---
+
+## Task 2: login.html — viewport meta
+
+**Files:**
+- Modify: `server/templates/login.html:4`
+
+- [ ] **Step 1: Add the viewport meta tag**
+
+In `server/templates/login.html`, replace the charset line:
+
+```html
+<meta charset="utf-8">
+```
+
+with:
+
+```html
+<meta charset="utf-8">
+<meta name="viewport" content="width=device-width, initial-scale=1">
+```
+
+(`login.html` needs no `@media`: its `body` is already
+`max-width: 360px`, the form is a column, and inputs are `width: 100%`.)
+
+- [ ] **Step 2: Verify its test passes**
+
+Run: `cargo test -p doctate-server --test responsive_test login_page_has_viewport_meta -j 4`
+Expected: PASS
+
+---
+
+## Task 3: my_cases.html — viewport meta + reflow breakpoint
+
+**Files:**
+- Modify: `server/templates/my_cases.html:6,78`
+
+- [ ] **Step 1: Add the viewport meta tag**
+
+In `server/templates/my_cases.html`, replace the charset line:
+
+```html
+<meta charset="utf-8">
+```
+
+with:
+
+```html
+<meta charset="utf-8">
+<meta name="viewport" content="width=device-width, initial-scale=1">
+```
+
+- [ ] **Step 2: Append the `@media` block before `</style>`**
+
+In `server/templates/my_cases.html`, replace the final rule + closing
+`</style>`:
+
+```html
+html.admin-view-off .admin-only { display: none !important; }
+</style>
+```
+
+with:
+
+```html
+html.admin-view-off .admin-only { display: none !important; }
+
+@media (max-width: 640px) {
+  body { margin: 1em auto; }
+  header { flex-wrap: wrap; gap: 0.6em; }
+  .case-row,
+  .case-list.has-bulk .case-row,
+  html.admin-view-off .case-list.has-bulk .case-row { grid-template-columns: 1fr; }
+  .case-row .actions { flex-wrap: wrap; }
+  .case-row .actions button,
+  .required-bar button,
+  .bulk-bar button { min-height: 44px; }
+  .case-row .actions .delete-btn,
+  .case-row .actions .reopen-btn { min-width: 44px; min-height: 44px; justify-content: center; }
+}
+</style>
+```
+
+- [ ] **Step 3: Verify its test passes**
+
+Run: `cargo test -p doctate-server --test responsive_test cases_list_has_viewport_and_media_query -j 4`
+Expected: PASS
+
+---
+
+## Task 4: case_recordings.html — viewport meta + player/touch breakpoint
+
+**Files:**
+- Modify: `server/templates/case_recordings.html:5,113`
+
+- [ ] **Step 1: Add the viewport meta tag**
+
+In `server/templates/case_recordings.html`, replace the charset line:
+
+```html
+<meta charset="utf-8">
+```
+
+with:
+
+```html
+<meta charset="utf-8">
+<meta name="viewport" content="width=device-width, initial-scale=1">
+```
+
+- [ ] **Step 2: Append the `@media` block before `</style>`**
+
+In `server/templates/case_recordings.html`, replace the final rule +
+closing `</style>`:
+
+```html
+.recording-head:has(.rec-delete-form.is-confirming) .player { visibility: hidden; }
+</style>
+```
+
+with:
+
+```html
+.recording-head:has(.rec-delete-form.is-confirming) .player { visibility: hidden; }
+
+@media (max-width: 640px) {
+  body { margin: 1em auto; }
+  header { flex-wrap: wrap; gap: 0.6em; }
+  .player { width: 100%; justify-content: flex-start; }
+  .player .seek { max-width: none; }
+  .player .play { width: 44px; height: 44px; }
+  .rec-delete-form .delete-btn { min-width: 44px; min-height: 44px; justify-content: center; }
+}
+</style>
+```
+
+- [ ] **Step 3: Verify its test passes**
+
+Run: `cargo test -p doctate-server --test responsive_test case_recordings_has_viewport_and_media_query -j 4`
+Expected: PASS
+
+---
+
+## Task 5: case_page.html — viewport meta + reflow breakpoint
+
+**Files:**
+- Modify: `server/templates/case_page.html:6,350`
+
+Note: this template uses 8-space-indented, multi-line CSS and a
+self-closing `<meta ... />` style — match it.
+
+- [ ] **Step 1: Add the viewport meta tag**
+
+In `server/templates/case_page.html`, replace the charset line:
+
+```html
+        <meta charset="utf-8" />
+```
+
+with:
+
+```html
+        <meta charset="utf-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1" />
+```
+
+- [ ] **Step 2: Append the `@media` block before `</style>`**
+
+In `server/templates/case_page.html`, replace the final rule + closing
+`</style>`:
+
+```html
+            html.admin-view-off .admin-only {
+                display: none !important;
+            }
+        </style>
+```
+
+with:
+
+```html
+            html.admin-view-off .admin-only {
+                display: none !important;
+            }
+            @media (max-width: 640px) {
+                body {
+                    margin: 1em auto;
+                }
+                .oneliner-input {
+                    min-width: 8em;
+                }
+                .doc-content {
+                    padding: 1em 1em;
+                }
+                .actions button {
+                    min-height: 44px;
+                }
+                .failure-banner dl.failure-details {
+                    grid-template-columns: 1fr;
+                }
+            }
+        </style>
+```
+
+- [ ] **Step 3: Verify its test passes**
+
+Run: `cargo test -p doctate-server --test responsive_test case_page_has_viewport_and_media_query -j 4`
+Expected: PASS
+
+---
+
+## Task 6: Full verification
+
+**Files:** (none — verification only)
+
+- [ ] **Step 1: Run the full responsive suite**
+
+Run: `cargo test -p doctate-server --test responsive_test -j 4`
+Expected: PASS — all 4 tests green.
+
+- [ ] **Step 2: Run the broader web/template tests for regressions**
+
+Run: `cargo test -p doctate-server --test web_test --test login_test --test case_page_test -j 4`
+Expected: PASS — viewport/`@media` additions are purely additive; no
+existing assertion changes.
+
+- [ ] **Step 3: cargo fmt**
+
+Run: `cargo fmt -p doctate-server`
+Expected: no diff in the new test file (it is already rustfmt-clean).
