refactor(locale-switcher): single flag-sized dropdown, drop 4-inline-flag UI

The nav previously showed 4 inline flag buttons (DE/EN/UK/RU) on desktop
and a details-based dropdown on mobile. Martin asked for one dropdown with
a trigger the size of a single flag, and the 4 inline flags to go away.

- LocaleSwitcher: render a single <details class='locale-switcher'>
  everywhere; trigger is one flag + tiny caret; menu lists all 4 with labels.
- Drop the 4-inline <ul> and the locale-switcher-mobile duplicate.
- CSS: replace both blocks with one compact dropdown (flag-sized trigger,
  44px touch target via padding, scrolled/transparent-nav variants).
- Tests: assert 4 menu options, 5 flag SVGs, single <details> dropdown,
  active locale is a <span aria-current>, others are <a> with hreflang.
- 141/141 PHPUnit green.

app/Controllers/LocaleSwitcher.php

@@ -11,13 +11,18 @@ use App\Core\Locale;
  * Renders the language switcher widget. Pure HTML generation — no
  * side effects, no header writing.
  *
- * Each option gets:
+ * Single <details>-based dropdown shown at every viewport. The
- *   - an inline 24×16 SVG flag (sub-Issue D),
+ * trigger is a flag-sized button (24×16 SVG + tiny caret) that
+ * opens to a menu of all 4 supported locales.
+ *
+ * Each menu option gets:
+ *   - an inline 24×16 SVG flag,
  *   - `hreflang` and `lang` for SEO and screen readers,
  *   - `aria-current="true"` on the active option.
  *
- * Active option is rendered as a <span> (not a link) so it cannot
+ * The active option is rendered as a <span> (not a link) so it
- * be reactivated. All options are ≥44px touch targets via CSS.
+ * cannot be reactivated. The trigger and every menu option are
+ * ≥44px touch targets via CSS.
  */
 final class LocaleSwitcher
 {
@@ -36,46 +41,6 @@ final class LocaleSwitcher
             'UTF-8',
         );
 
-        $html  = '<div class="locale-switcher-wrapper">';
-        $html .= '<ul class="locale-switcher" role="list" aria-label="' . $ariaLabel . '">';
-        foreach (Locale::SUPPORTED as $code) {
-            $isCurrent = $code === $this->currentLocale;
-            $name      = htmlspecialchars(
-                I18n::t('locale.' . $code, [], $this->currentLocale),
-                ENT_QUOTES,
-                'UTF-8',
-            );
-            $codeAttr  = htmlspecialchars($code, ENT_QUOTES, 'UTF-8');
-            $flag      = self::flagSvg($code);
-
-            $classes = 'locale-switcher__option';
-            if ($isCurrent) {
-                $classes .= ' is-current';
-            }
-
-            $html .= '<li class="locale-switcher__item">';
-            if ($isCurrent) {
-                $html .= '<span class="' . $classes . '" aria-current="true" lang="' . $codeAttr . '">'
-                       . $flag
-                       . '<span class="locale-switcher__label">' . $name . '</span>'
-                       . '</span>';
-            } else {
-                $url = '/locale?set=' . rawurlencode($code) . '&amp;return=' . rawurlencode($path);
-                $html .= '<a class="' . $classes . '"'
-                       . ' href="' . $url . '"'
-                       . ' hreflang="' . $codeAttr . '"'
-                       . ' lang="' . $codeAttr . '"'
-                       . ' rel="alternate"'
-                       . '>'
-                       . $flag
-                       . '<span class="locale-switcher__label">' . $name . '</span>'
-                       . '</a>';
-            }
-            $html .= '</li>';
-        }
-        $html .= '</ul>';
-
-        // Mobile dropdown — compact single-trigger switcher for narrow viewports
         $currentName = htmlspecialchars(
             I18n::t('locale.' . $this->currentLocale, [], $this->currentLocale),
             ENT_QUOTES,
@@ -83,15 +48,18 @@ final class LocaleSwitcher
         );
         $currentCode = htmlspecialchars($this->currentLocale, ENT_QUOTES, 'UTF-8');
         $currentFlag = self::flagSvg($this->currentLocale);
-        $html .= '<details class="locale-switcher-mobile">';
+
-        $html .= '<summary class="locale-switcher-mobile__trigger" aria-label="' . $ariaLabel . '">';
+        $html  = '<details class="locale-switcher">';
-        $html .= '<span class="locale-switcher-mobile__current" lang="' . $currentCode . '">';
+        $html .= '<summary class="locale-switcher__trigger"'
+               . ' aria-label="' . $ariaLabel . '"'
+               . ' title="' . $currentName . '"'
+               . '>';
+        $html .= '<span class="locale-switcher__current" lang="' . $currentCode . '">';
         $html .= $currentFlag;
-        $html .= '<span class="locale-switcher-mobile__current-code">' . strtoupper($currentCode) . '</span>';
         $html .= '</span>';
-        $html .= '<span class="locale-switcher-mobile__caret" aria-hidden="true">▾</span>';
+        $html .= '<span class="locale-switcher__caret" aria-hidden="true">▾</span>';
         $html .= '</summary>';
-        $html .= '<ul class="locale-switcher-mobile__menu" role="list">';
+        $html .= '<ul class="locale-switcher__menu" role="list">';
         foreach (Locale::SUPPORTED as $code) {
             $isCurrent = $code === $this->currentLocale;
             $name      = htmlspecialchars(
@@ -104,23 +72,28 @@ final class LocaleSwitcher
 
             $html .= '<li>';
             if ($isCurrent) {
-                $html .= '<span class="locale-switcher-mobile__option is-current" aria-current="true" lang="' . $codeAttr . '">'
+                $html .= '<span class="locale-switcher__option is-current"'
-                       . $flag . '<span>' . $name . '</span></span>';
+                       . ' aria-current="true"'
+                       . ' lang="' . $codeAttr . '">'
+                       . $flag
+                       . '<span class="locale-switcher__label">' . $name . '</span>'
+                       . '</span>';
             } else {
                 $url = '/locale?set=' . rawurlencode($code) . '&amp;return=' . rawurlencode($path);
-                $html .= '<a class="locale-switcher-mobile__option"'
+                $html .= '<a class="locale-switcher__option"'
                        . ' href="' . $url . '"'
                        . ' hreflang="' . $codeAttr . '"'
                        . ' lang="' . $codeAttr . '"'
                        . ' rel="alternate"'
                        . '>'
-                       . $flag . '<span>' . $name . '</span></a>';
+                       . $flag
+                       . '<span class="locale-switcher__label">' . $name . '</span>'
+                       . '</a>';
             }
             $html .= '</li>';
         }
         $html .= '</ul>';
         $html .= '</details>';
-        $html .= '</div>';
 
         return $html;
     }

public/css/haus-schleusingen.css

@@ -100,7 +100,6 @@ nav {
   padding: 0.95rem 3rem;
   background: var(--nav-bg);
   backdrop-filter: saturate(180%) blur(14px);
-  backdrop-filter: saturate(180%) blur(14px);
   border-bottom: 1px solid var(--nav-border);
   transition:
     padding 0.3s ease,
@@ -962,8 +961,6 @@ nav.scrolled {
   width: 32px;
   height: 32px;
   background: var(--accent);
-  mask: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'><path d='M12 2C8.13 2 5 5.13 5 9c0 5.25 7 13 7 13s7-7.75 7-13c0-3.87-3.13-7-7-7zm0 9.5a2.5 2.5 0 110-5 2.5 2.5 0 010 5z'/></svg>")
-    center/contain no-repeat;
   mask: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'><path d='M12 2C8.13 2 5 5.13 5 9c0 5.25 7 13 7 13s7-7.75 7-13c0-3.87-3.13-7-7-7zm0 9.5a2.5 2.5 0 110-5 2.5 2.5 0 010 5z'/></svg>")
     center/contain no-repeat;
   margin-bottom: 0.5rem;
@@ -1131,8 +1128,6 @@ nav.scrolled {
 }
 
 .form-field select {
-  appearance: none;
-  appearance: none;
   appearance: none;
   background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'><path d='M1 1l5 5 5-5' stroke='%237a7062' stroke-width='1.5' fill='none' stroke-linecap='round' stroke-linejoin='round'/></svg>");
   background-repeat: no-repeat;
@@ -1367,19 +1362,6 @@ footer {
     display: none;
   }
 
-  /* Locale switcher: replace 4-flag list with single-trigger dropdown */
-  .locale-switcher {
-    display: none;
-  }
-
-  .locale-switcher-mobile {
-    display: block;
-  }
-
-  .locale-switcher-mobile[open] > .locale-switcher-mobile__menu {
-    display: block;
-  }
-
   /* Mobile slide-down nav */
   nav.mobile-open .nav-links {
     display: flex;
@@ -1494,79 +1476,94 @@ footer {
   }
 }
 
-/* LOCALE SWITCHER (sub-Issue D) — desktop only */
+/* LOCALE SWITCHER — single <details> dropdown, flag-sized trigger */
-@media (width > 900px) {
+.locale-switcher {
-  .locale-switcher {
+  position: relative;
-    display: flex;
+  display: inline-block;
-    align-items: center;
-    gap: 0.25rem;
-    list-style: none;
-    margin: 0;
-    padding: 0;
-  }
 }
 
-.locale-switcher__item {
+.locale-switcher__trigger {
-  display: flex;
+  display: inline-flex;
+  align-items: center;
+  gap: 0.25rem;
+  padding: 14px 8px;
+  border: none;
+  border-radius: 4px;
+  background: transparent;
+  cursor: pointer;
+  list-style: none;
+  min-height: 44px;
+  min-width: 44px;
+  color: var(--dark);
+  transition:
+    background 0.2s,
+    transform 0.15s;
+}
+
+.locale-switcher__trigger::-webkit-details-marker {
+  display: none;
+}
+
+.locale-switcher__trigger:hover,
+.locale-switcher__trigger:focus-visible {
+  background: rgb(0 0 0 / 6%);
+  outline: none;
+}
+
+.locale-switcher__current {
+  display: inline-flex;
+  align-items: center;
+}
+
+.locale-switcher__caret {
+  font-size: 0.65rem;
+  line-height: 1;
+  color: inherit;
+  transition: transform 0.2s ease;
+  margin-left: 2px;
+}
+
+.locale-switcher[open] .locale-switcher__caret {
+  transform: rotate(180deg);
+}
+
+.locale-switcher__menu {
+  position: absolute;
+  top: calc(100% + 6px);
+  right: 0;
+  min-width: 180px;
+  margin: 0;
+  padding: 0.4rem;
+  list-style: none;
+  background: var(--white);
+  border: 1px solid var(--warm);
+  border-radius: 8px;
+  box-shadow: 0 8px 24px rgb(0 0 0 / 14%);
+  z-index: 60;
 }
 
 .locale-switcher__option {
-  display: inline-flex;
+  display: flex;
   align-items: center;
-  gap: 0.4rem;
+  gap: 0.6rem;
-  min-height: 44px;
+  padding: 0.6rem 0.7rem;
-  min-width: 44px;
-  padding: 0.45rem 0.55rem;
-  border: 1px solid transparent;
   border-radius: 4px;
   text-decoration: none;
-  font-size: 0.78rem;
+  color: var(--dark);
-  font-weight: 500;
+  font-size: 0.85rem;
-  letter-spacing: 0.04em;
+  min-height: 44px;
-  color: var(--text-muted-on-dark);
+}
-  background: transparent;
+
-  transition:
+.locale-switcher__option.is-current {
-    background 0.2s,
+  background: var(--cream);
-    border-color 0.2s,
+  color: var(--accent-strong);
-    color 0.2s,
+  font-weight: 600;
-    transform 0.15s;
-  cursor: pointer;
 }
 
 .locale-switcher__option:hover,
 .locale-switcher__option:focus-visible {
-  background: rgb(255 255 255 / 14%);
-  border-color: rgb(255 255 255 / 30%);
-  color: var(--white);
-  transform: translateY(-1px);
-}
-
-.locale-switcher__option.is-current {
-  background: rgb(255 255 255 / 20%);
-  border-color: var(--accent-light);
-  color: var(--white);
-  cursor: default;
-}
-
-.locale-switcher__option.is-current:hover {
-  transform: none;
-}
-
-nav.scrolled .locale-switcher__option {
-  color: var(--stone);
-}
-
-nav.scrolled .locale-switcher__option:hover,
-nav.scrolled .locale-switcher__option:focus-visible {
   background: var(--warm);
-  border-color: var(--stone);
+  outline: none;
-  color: var(--dark);
-}
-
-nav.scrolled .locale-switcher__option.is-current {
-  background: var(--cream);
-  border-color: var(--accent);
-  color: var(--dark);
 }
 
 .locale-switcher__option .flag {
@@ -1582,26 +1579,18 @@ nav.scrolled .locale-switcher__option.is-current {
   white-space: nowrap;
 }
 
-/* Hide labels on small screens, keep the 44px flag target */
+/* Trigger on transparent nav (top-of-page): white caret on dark bg */
-@media (width <= 720px) {
+nav:not(.scrolled) .locale-switcher__trigger {
-  .locale-switcher__label {
+  color: var(--white);
-    position: absolute;
-    width: 1px;
-    height: 1px;
-    padding: 0;
-    margin: -1px;
-    overflow: hidden;
-    clip-path: inset(50%);
-    white-space: nowrap;
-    border: 0;
-  }
-
-  .locale-switcher__option {
-    min-width: 44px;
-    padding: 0.55rem;
-  }
 }
 
+nav:not(.scrolled) .locale-switcher__trigger:hover,
+nav:not(.scrolled) .locale-switcher__trigger:focus-visible {
+  background: rgb(255 255 255 / 12%);
+}
+
+/* Flag stays the same regardless of nav state — SVG defines its own colours */
+
 /* VISUALLY HIDDEN (a11y) */
 .visually-hidden {
   position: absolute;
@@ -1615,110 +1604,6 @@ nav.scrolled .locale-switcher__option.is-current {
   border: 0;
 }
 
-/* MOBILE LOCALE SWITCHER (dropdown — defaults to hidden on desktop) */
-@media (width > 900px) {
-  .locale-switcher-mobile {
-    display: none;
-  }
-}
-
-.locale-switcher-mobile {
-  position: relative;
-}
-
-.locale-switcher-mobile__trigger {
-  display: inline-flex;
-  align-items: center;
-  gap: 0.4rem;
-  padding: 0.55rem 0.7rem;
-  border: 1px solid rgb(0 0 0 / 12%);
-  border-radius: 6px;
-  background: rgb(255 255 255 / 95%);
-  cursor: pointer;
-  list-style: none;
-  min-height: 44px;
-  color: var(--dark);
-  font-size: 0.78rem;
-  font-weight: 600;
-  letter-spacing: 0.04em;
-}
-
-.locale-switcher-mobile__trigger::-webkit-details-marker {
-  display: none;
-}
-
-.locale-switcher-mobile__current {
-  display: inline-flex;
-  align-items: center;
-  gap: 0.4rem;
-}
-
-.locale-switcher-mobile__current-code {
-  letter-spacing: 0.05em;
-}
-
-.locale-switcher-mobile__caret {
-  font-size: 0.7rem;
-  transition: transform 0.2s ease;
-}
-
-.locale-switcher-mobile[open] .locale-switcher-mobile__caret {
-  transform: rotate(180deg);
-}
-
-.locale-switcher-mobile__menu {
-  position: absolute;
-  top: calc(100% + 6px);
-  right: 0;
-  min-width: 180px;
-  margin: 0;
-  padding: 0.4rem;
-  list-style: none;
-  background: var(--white);
-  border: 1px solid var(--warm);
-  border-radius: 8px;
-  box-shadow: 0 8px 24px rgb(0 0 0 / 12%);
-  z-index: 60;
-  display: none;
-}
-
-.locale-switcher-mobile__option {
-  display: flex;
-  align-items: center;
-  gap: 0.6rem;
-  padding: 0.6rem 0.7rem;
-  border-radius: 4px;
-  text-decoration: none;
-  color: var(--dark);
-  font-size: 0.85rem;
-  min-height: 44px;
-}
-
-.locale-switcher-mobile__option.is-current {
-  background: var(--cream);
-  color: var(--accent-strong);
-  font-weight: 600;
-}
-
-.locale-switcher-mobile__option:hover,
-.locale-switcher-mobile__option:focus-visible {
-  background: var(--warm);
-  outline: none;
-}
-
-nav.scrolled .locale-switcher-mobile__trigger {
-  background: var(--white);
-  color: var(--dark);
-  border-color: var(--warm);
-}
-
-nav:not(.scrolled) .locale-switcher-mobile__trigger {
-  background: rgb(255 255 255 / 12%);
-  color: var(--white);
-  border-color: rgb(255 255 255 / 30%);
-  backdrop-filter: blur(4px);
-}
-
 /* FORM FIELD ERRORS (sub-Issue E) */
 .form-field-error {
   margin: 0.375rem 0 0;

tests/Controllers/LocaleSwitcherTest.php

@@ -11,20 +11,28 @@ use PHPUnit\Framework\TestCase;
 
 /**
  * Renders the language switcher widget and checks that:
- *   - 4 items, one per supported locale,
+ *   - exactly one <details class="locale-switcher"> dropdown,
+ *   - 4 menu items, one per supported locale,
  *   - the active locale is marked aria-current="true" and is a <span>,
  *   - inactive locales are <a> links to /locale?set=...&return=...,
- *   - every item contains a flag SVG,
+ *   - the trigger and every menu item contain a flag SVG,
  *   - the rendered label is in the current locale's language.
  */
 final class LocaleSwitcherTest extends TestCase
 {
     #[Test]
-    public function rendersFourItemsForAllSupportedLocales(): void
+    public function rendersSingleDropdownForAllSupportedLocales(): void
     {
         $html = (new LocaleSwitcher('en', '/'))->render();
-        self::assertStringContainsString('<ul class="locale-switcher"', $html);
+
-        self::assertStringContainsString('<details class="locale-switcher-mobile"', $html);
+        // exactly one <details class="locale-switcher"> (no -mobile suffix, no desktop <ul>)
+        self::assertStringContainsString('<details class="locale-switcher">', $html);
+        self::assertStringNotContainsString('locale-switcher-mobile', $html);
+        self::assertStringNotContainsString('<ul class="locale-switcher"', $html);
+        self::assertStringNotContainsString('locale-switcher__item', $html);
+
+        // the menu lists all 4 supported locales
+        self::assertSame(4, substr_count($html, 'class="locale-switcher__option'), 'expected 4 menu options');
 
         // The 3 inactive locales render as <a hreflang="..">. The active
         // locale renders as <span lang=".."> (no hreflang). Together all
@@ -35,10 +43,9 @@ final class LocaleSwitcherTest extends TestCase
                 "locale '$code' is missing from switcher",
             );
         }
-        // Both the desktop list and the mobile dropdown render a flag per locale
+
-        self::assertSame(4, substr_count($html, 'class="locale-switcher__option'), 'expected 4 desktop options');
+        // 1 flag in trigger + 4 flags in menu = 5 total
-        self::assertSame(4, substr_count($html, 'class="locale-switcher-mobile__option'), 'expected 4 mobile options');
+        self::assertSame(5, substr_count($html, 'class="flag"'), 'expected 5 flag SVGs (1 trigger + 4 menu)');
-        self::assertSame(9, substr_count($html, 'class="flag"'), 'expected 9 flag SVGs (4 desktop + 4 mobile menu + 1 mobile trigger)');
     }
 
     #[Test]
@@ -129,4 +136,17 @@ final class LocaleSwitcherTest extends TestCase
         self::assertStringContainsString('aria-label="Sprache wählen"', $htmlDe);
         self::assertStringContainsString('aria-label="Choose language"', $htmlEn);
     }
+
+    #[Test]
+    public function triggerContainsCurrentLocaleFlag(): void
+    {
+        // The closed dropdown shows the current locale's flag in the trigger
+        $html = (new LocaleSwitcher('de', '/'))->render();
+        // The first <svg class="flag"> in the document is the trigger
+        self::assertStringContainsString('<svg class="flag" viewBox="0 0 24 16"', $html);
+        // The first flag SVG must contain the German colours
+        $deFlag = LocaleSwitcher::flagSvg('de');
+        $pos = strpos($html, $deFlag);
+        self::assertNotFalse($pos, 'expected German flag SVG in the trigger (first <svg> in document)');
+    }
 }