fix(frontend): フォーカス/タブ移動に関する挙動を調整 (#226)

Cherry-pick commit e8c030673326871edf3623cf2b8675d68f9e1b13

Co-authored-by: taiyme <53635909+taiyme@users.noreply.github.com>

packages/frontend/src/components/MkMediaAudio.vue

@@ -39,23 +39,37 @@ SPDX-License-Identifier: AGPL-3.0-only
 		<audio
 			ref="audioEl"
 			preload="metadata"
+			@keydown.prevent="() => {}"
 		>
 			<source :src="audio.url">
 		</audio>
 		<div :class="[$style.controlsChild, $style.controlsLeft]">
-			<button class="_button" :class="$style.controlButton" @click="togglePlayPause">
+			<button
+				:class="['_button', $style.controlButton]"
+				tabindex="-1"
+				@click.stop="togglePlayPause"
+			>
 				<i v-if="isPlaying" class="ti ti-player-pause-filled"></i>
 				<i v-else class="ti ti-player-play-filled"></i>
 			</button>
 		</div>
 		<div :class="[$style.controlsChild, $style.controlsRight]">
-			<button class="_button" :class="$style.controlButton" @click="showMenu">
+			<button
+				:class="['_button', $style.controlButton]"
+				tabindex="-1"
+				@click.stop="() => {}"
+				@mousedown.prevent.stop="showMenu"
+			>
 				<i class="ti ti-settings"></i>
 			</button>
 		</div>
 		<div :class="[$style.controlsChild, $style.controlsTime]">{{ hms(elapsedTimeMs) }}</div>
 		<div :class="[$style.controlsChild, $style.controlsVolume]">
-			<button class="_button" :class="$style.controlButton" @click="toggleMute">
+			<button
+				:class="['_button', $style.controlButton]"
+				tabindex="-1"
+				@click.stop="toggleMute"
+			>
 				<i v-if="volume === 0" class="ti ti-volume-3"></i>
 				<i v-else class="ti ti-volume"></i>
 			</button>
@@ -64,6 +78,10 @@ SPDX-License-Identifier: AGPL-3.0-only
 				:class="$style.volumeSeekbar"
 			/>
 		</div>
+		<MkMediaRange
+			v-model="volume"
+			:class="$style.volumeSeekbar"
+		/>
 		<MkMediaRange
 			v-model="rangePercent"
 			:class="$style.seekbarRoot"
@@ -371,7 +389,7 @@ onDeactivated(() => {
 	border-radius: var(--radius);
 	overflow: clip;
 
-	&:focus {
+	&:focus-visible {
 		outline: none;
 	}
 }
@@ -437,6 +455,10 @@ onDeactivated(() => {
 			color: var(--accent);
 			background-color: var(--accentedBg);
 		}
+
+		&:focus-visible {
+			outline: none;
+		}
 	}
 }