Mobile declutter pass: step flows, compact cards, simplified settings

Phones only (<=639px); desktop markup is untouched.

- New deck is a 3-step flow: progress (1/3 + bar) and a fixed Back/Next
  bar above the tab bar. Step 1 = Add photos or files / Camera / Paste
  text instead (no drop zone or paste copy on touch), step 2 = folder,
  difficulty and count with defaults plus one collapsed focus/notes row,
  step 3 = one summary line (photos/docs/text · difficulty · count ·
  folder) with Freeze. Going Back keeps every input; step transitions
  respect prefers-reduced-motion.
- Make my homework is a 2-step flow sharing the same pattern; tapping a
  mode card starts it (no separate CTA on phones), with a short preview
  of the assignment on step 2. The hero is now 'Make my homework' /
  'Udělej mi úkol' everywhere ('Solve your homework' is gone) and the
  intro is one line.
- Library: stats line removed, folder row and 'Unorganized' heading
  hidden until folders exist (New folder lives in the drawer), Import is
  a small icon button beside the tabs. Deck and homework cards are
  compact on phones: title, one meta line (activities · difficulty ·
  best), a one-line description that expands on tap, the whole card
  tappable and a small Study/Open pill instead of the full-width button.
- Settings sheet on phones: no .env.local subtitle; Language stays first;
  one Connection card (status dot + 'Connected · 2 models ready', key
  field with the eye inside, Save only when edited, auto re-check on
  save, refresh icon instead of Test connection); privacy one-liner with
  a More expander (daemon tip inside); raw health rows behind one
  collapsed Details list; Remove key as a small danger button at the very
  bottom (same confirmation).
- Decorative orbs on phones moved further off the screen edges so they
  never glow under cards or primary buttons.
- Shared markup for folder/difficulty/count and mode cards keeps one
  source of state; new lib/use-phone.ts gates the layouts.

Verified: new declutter suite 116/116 (360 + 390, EN + CS, photo + PDF +
pasted text, Back keeps input, summaries, settings flow), regression
74/74, mobile 52/52, i18n 25/25. Lint + build clean. SW freezmo-v20.

components/HomeworkCard.tsx

@@ -3,11 +3,11 @@
 import Link from "next/link";
 import { useState } from "react";
 
-import { BoltIcon, PlayIcon, XIcon } from "@/components/icons";
+import { BoltIcon, ChevronDownIcon, PlayIcon, XIcon } from "@/components/icons";
 import { Button } from "@/components/ui";
 import { useI18n } from "@/lib/i18n";
 import type { HomeworkRecord } from "@/lib/schemas";
-import { formatDate, truncate } from "@/lib/utils";
+import { cn, formatDate, truncate } from "@/lib/utils";
 
 /**
  * One saved homework result in the library's Homework tab: the finished
@@ -16,6 +16,7 @@ import { formatDate, truncate } from "@/lib/utils";
 export function HomeworkCard({ record, onDelete }: { record: HomeworkRecord; onDelete: (id: string) => void }) {
   const { t, plural } = useI18n();
   const [confirmDelete, setConfirmDelete] = useState(false);
+  const [expanded, setExpanded] = useState(false);
   const href = `/homework?open=${record.id}`;
 
   const preview =
@@ -27,9 +28,9 @@ export function HomeworkCard({ record, onDelete }: { record: HomeworkRecord; onD
         );
 
   return (
-    <li className="card card-hover group relative flex flex-col p-5">
-      {/* Desktop: the whole card opens the result; the delete button sits above it. */}
-      <Link href={href} aria-hidden="true" tabIndex={-1} className="absolute inset-0 hidden rounded-[1.5rem] lg:block" />
+    <li className="card card-hover group relative flex flex-col p-4 sm:p-5">
+      {/* Phones: the whole card opens the result too; the delete button sits above it. */}
+      <Link href={href} aria-hidden="true" tabIndex={-1} className="absolute inset-0 hidden rounded-[1.5rem] max-sm:block lg:block" />
 
       <div className="flex items-start justify-between gap-3">
         <div className="min-w-0 flex-1">
@@ -65,10 +66,23 @@ export function HomeworkCard({ record, onDelete }: { record: HomeworkRecord; onD
       </div>
 
       {preview ? (
-        <p className="mt-3 line-clamp-2 text-[13.5px] leading-relaxed text-[var(--text-muted)]">{preview}</p>
+        <>
+          <button
+            type="button"
+            aria-expanded={expanded}
+            onClick={() => setExpanded((value) => !value)}
+            className="relative z-10 mt-2 flex w-full items-start gap-1 text-left text-[13px] leading-relaxed text-[var(--text-muted)] sm:hidden"
+          >
+            <span className={cn("min-w-0 flex-1", !expanded && "line-clamp-1")}>{preview}</span>
+            <ChevronDownIcon
+              className={cn("mt-0.5 size-4 shrink-0 text-[var(--text-subtle)] transition-transform", expanded && "rotate-180")}
+            />
+          </button>
+          <p className="mt-3 hidden line-clamp-2 text-[13.5px] leading-relaxed text-[var(--text-muted)] sm:block">{preview}</p>
+        </>
       ) : null}
 
-      <div className="mt-5 lg:mt-4">
+      <div className="mt-4 flex justify-end lg:mt-4">
         {confirmDelete ? (
           <div className="relative z-10 flex flex-wrap items-center gap-2">
             <span className="text-[12.5px] text-[var(--text-muted)]">{t("homework.history.deleteConfirm")}</span>
@@ -81,7 +95,14 @@ export function HomeworkCard({ record, onDelete }: { record: HomeworkRecord; onD
           </div>
         ) : (
           <>
-            <Link href={href} className="btn-primary touch-target h-10 w-full px-4 text-sm lg:hidden">
+            <Link
+              href={href}
+              className="btn-primary touch-target relative z-10 h-9 gap-1.5 px-3.5 text-[13px] sm:hidden"
+            >
+              <PlayIcon className="size-4" />
+              {t("homework.open")}
+            </Link>
+            <Link href={href} className="btn-primary hidden h-10 w-full px-4 text-sm sm:flex lg:hidden">
               {t("homework.open")}
             </Link>
             <div className="relative z-10 hidden lg:flex lg:justify-end">