apps/web/cypress/e2e/leftovers-basket.cy.ts

@@ -105,4 +105,23 @@ describe("Leftovers basket", () => {
     cy.contains(".leftovers-basket__empty", "Aucun reste cette semaine.").should("be.visible");
     cy.get(".leftovers-basket__count").should("not.exist");
   });
+
+  it("opens inside a bottom sheet on a phone instead of the anchored popover", () => {
+    // Literal 390×844 rather than `cy.setViewport("phone")` (ticket #83) —
+    // that command doesn't exist on this ticket's own base yet; matches its
+    // PHONE_VIEWPORT value on purpose, worth switching to the real import
+    // once both have landed on `main`.
+    cy.viewport(390, 844);
+    cy.intercept("GET", /\/planning\?/, { statusCode: 200, body: planningWithLeftovers });
+    cy.visit("/");
+
+    cy.get(".leftovers-basket__toggle").click();
+    cy.get(".leftovers-basket__popover").should("not.exist");
+    cy.get(".bottom-sheet").should("be.visible");
+    cy.contains(".bottom-sheet", "Restes disponibles").should("be.visible");
+    cy.contains(".bottom-sheet .leftovers-basket__line", "Lasagnes").should("be.visible");
+
+    cy.get(".bottom-sheet__close").click();
+    cy.get(".bottom-sheet").should("not.exist");
+  });
 });

apps/web/cypress/e2e/planning-page.cy.ts

@@ -197,4 +197,25 @@ describe("Planning grid", () => {
     cy.contains("Semaine du 24 au 30 août 2026").should("be.visible");
     cy.get(".calendar-popover").should("not.exist");
   });
+
+  it("opens the calendar inside a bottom sheet on a phone instead of the anchored popover", () => {
+    // Literal 390×844 rather than `cy.setViewport("phone")` (ticket #83) —
+    // that command doesn't exist on this ticket's own base yet; matches its
+    // PHONE_VIEWPORT value on purpose, worth switching to the real import
+    // once both have landed on `main`.
+    cy.viewport(390, 844);
+    cy.intercept("GET", /\/planning\?/, { statusCode: 200, body: null }).as("getPlanning");
+
+    cy.visit("/");
+    cy.wait("@getPlanning");
+
+    cy.contains("button", "Semaine du").click();
+    cy.get(".calendar-popover").should("not.exist");
+    cy.get(".bottom-sheet").should("be.visible");
+    cy.contains(".bottom-sheet", "Choisir une semaine").should("be.visible");
+
+    cy.get(".bottom-sheet .calendar-grid__day").contains(/^25$/).click();
+    cy.contains("Semaine du 24 au 30 août 2026").should("be.visible");
+    cy.get(".bottom-sheet").should("not.exist");
+  });
 });

apps/web/src/features/planning/LeftoversBasket.tsx

@@ -3,6 +3,8 @@ import { useDraggable } from "@dnd-kit/core";
 import { useEffect, useRef, useState } from "react";
 import { useTranslation } from "react-i18next";
 import { apiClient } from "../../api/client";
+import { BottomSheet } from "../../components/ui/BottomSheet";
+import { useIsMobileViewport } from "../../lib/useIsMobileViewport";
 import { collectLeftoverLines, dragIdForLeftover } from "./leftovers-basket";
 import "./leftovers-basket.scss";
 
@@ -19,6 +21,13 @@ import "./leftovers-basket.scss";
  * The list is derived on every render from `planning` (see
  * {@link collectLeftoverLines}) rather than held in its own state, so a
  * discard or assignment elsewhere on the page is reflected here for free.
+ *
+ * On a phone this renders inside a {@link BottomSheet} instead of the
+ * plain anchored `div` below — the fixed-width popover (`right: 0`, no
+ * edge handling) used to render identically at every width, which could
+ * push it partly or fully off a narrow screen (see the mobile/tablet UI
+ * chantier's own audit — very plausibly *the* concrete cause of reported
+ * "can't reach a button" complaints on mobile).
  */
 export function LeftoversBasket({
   planning,
@@ -29,6 +38,7 @@ export function LeftoversBasket({
   onLeftoverDiscarded: (item: PlanningItemView) => void;
 }) {
   const { t } = useTranslation();
+  const isMobile = useIsMobileViewport();
   const [isOpen, setIsOpen] = useState(false);
   const [discardingId, setDiscardingId] = useState<number | null>(null);
   const popoverRef = useRef<HTMLDivElement>(null);
@@ -36,7 +46,12 @@ export function LeftoversBasket({
   const lines = collectLeftoverLines(planning);
 
   useEffect(() => {
-    if (!isOpen) return;
+    // On mobile the BottomSheet branch below never attaches this ref (it's
+    // a native <dialog> with its own tap-outside handling instead) —
+    // `popoverRef.current` would just stay `null` and this would silently
+    // no-op every time, harmless but pointless, so skip attaching the
+    // listener at all in that case.
+    if (!isOpen || isMobile) return;
     function handleClickOutside(e: MouseEvent) {
       if (popoverRef.current && !popoverRef.current.contains(e.target as Node)) {
         setIsOpen(false);
@@ -44,7 +59,7 @@ export function LeftoversBasket({
     }
     document.addEventListener("mousedown", handleClickOutside);
     return () => document.removeEventListener("mousedown", handleClickOutside);
-  }, [isOpen]);
+  }, [isOpen, isMobile]);
 
   async function discard(item: PlanningItemView) {
     setDiscardingId(item.id);
@@ -59,6 +74,23 @@ export function LeftoversBasket({
     }
   }
 
+  const listContent =
+    lines.length === 0 ? (
+      <p className="leftovers-basket__empty">{t("planning.leftovers.empty")}</p>
+    ) : (
+      <ul className="leftovers-basket__list">
+        {lines.map(({ item, available }) => (
+          <LeftoverLineCard
+            key={item.id}
+            item={item}
+            available={available}
+            isDiscarding={discardingId === item.id}
+            onDiscard={() => void discard(item)}
+          />
+        ))}
+      </ul>
+    );
+
   return (
     <div className="leftovers-basket">
       <button
@@ -73,26 +105,17 @@ export function LeftoversBasket({
         {lines.length > 0 && <span className="leftovers-basket__count">{lines.length}</span>}
       </button>
 
-      {isOpen && (
+      {isOpen &&
+        (isMobile ? (
+          <BottomSheet onClose={() => setIsOpen(false)} title={t("planning.leftovers.title")}>
+            {listContent}
+          </BottomSheet>
+        ) : (
           <div className="leftovers-basket__popover" ref={popoverRef}>
             <h2 className="leftovers-basket__heading">{t("planning.leftovers.title")}</h2>
-          {lines.length === 0 ? (
-            <p className="leftovers-basket__empty">{t("planning.leftovers.empty")}</p>
-          ) : (
-            <ul className="leftovers-basket__list">
-              {lines.map(({ item, available }) => (
-                <LeftoverLineCard
-                  key={item.id}
-                  item={item}
-                  available={available}
-                  isDiscarding={discardingId === item.id}
-                  onDiscard={() => void discard(item)}
-                />
-              ))}
-            </ul>
-          )}
+            {listContent}
           </div>
-      )}
+        ))}
     </div>
   );
 }

apps/web/src/features/planning/WeekNavigator.tsx

@@ -8,6 +8,8 @@ import {
 import { WEEK_DAYS } from "@batch-cooking/shared";
 import { useEffect, useRef, useState } from "react";
 import { useTranslation } from "react-i18next";
+import { BottomSheet } from "../../components/ui/BottomSheet";
+import { useIsMobileViewport } from "../../lib/useIsMobileViewport";
 import "./week-navigator.scss";
 
 /** "17 au 23 août 2026" — collapses the month/year to just the end date when both ends of the week share it, spells it out on both ends otherwise (e.g. a week straddling two months). */
@@ -89,7 +91,15 @@ export function WeekNavigator({
   );
 }
 
-/** Month calendar letting the visitor jump to any week at once — selecting a day selects its whole (Monday-first) week. Closes itself on an outside click. */
+/**
+ * Month calendar letting the visitor jump to any week at once — selecting a
+ * day selects its whole (Monday-first) week. Closes itself on an outside
+ * click on desktop; on a phone it renders inside a {@link BottomSheet}
+ * instead of the plain anchored `div` below, same reasoning as
+ * `LeftoversBasket`'s identical split — a fixed-width popover with no
+ * viewport-edge handling can otherwise render partly or fully off a narrow
+ * screen.
+ */
 function CalendarPopover({
   selectedWeekStart,
   onSelectDay,
@@ -100,6 +110,7 @@ function CalendarPopover({
   onClose: () => void;
 }) {
   const { t } = useTranslation();
+  const isMobile = useIsMobileViewport();
   // Its own state: browsing to a different month to pick a week there
   // shouldn't jump back every render — only re-anchors when the popover is
   // first opened (`selectedWeekStart` at that point), not while it's open.
@@ -107,6 +118,11 @@ function CalendarPopover({
   const popoverRef = useRef<HTMLDivElement>(null);
 
   useEffect(() => {
+    // See LeftoversBasket's identical guard: on mobile this ref never
+    // attaches to anything (the BottomSheet branch below handles its own
+    // tap-outside-to-close), so the listener would just be a permanent
+    // no-op — skip attaching it at all in that case.
+    if (isMobile) return;
     function handleClickOutside(e: MouseEvent) {
       if (popoverRef.current && !popoverRef.current.contains(e.target as Node)) {
         onClose();
@@ -114,14 +130,14 @@ function CalendarPopover({
     }
     document.addEventListener("mousedown", handleClickOutside);
     return () => document.removeEventListener("mousedown", handleClickOutside);
-  }, [onClose]);
+  }, [onClose, isMobile]);
 
   const today = toDateOnly(DateTime.utc());
   const selectedWeekEnd = selectedWeekStart.plus({ days: 6 });
   const weeks = buildCalendarMonth(visibleMonth);
 
-  return (
-    <div className="calendar-popover" ref={popoverRef}>
+  const calendarContent = (
+    <>
       <div className="calendar-popover__header">
         <button
           type="button"
@@ -169,6 +185,20 @@ function CalendarPopover({
           );
         })}
       </div>
+    </>
+  );
+
+  if (isMobile) {
+    return (
+      <BottomSheet onClose={onClose} title={t("common.calendar.title")}>
+        {calendarContent}
+      </BottomSheet>
+    );
+  }
+
+  return (
+    <div className="calendar-popover" ref={popoverRef}>
+      {calendarContent}
     </div>
   );
 }

apps/web/src/locales/fr/translation.json

@@ -10,6 +10,7 @@
       "label": "Semaine du {{range}}"
     },
     "calendar": {
+      "title": "Choisir une semaine",
       "prevMonth": "Mois précédent",
       "nextMonth": "Mois suivant"
     },