several small ui updates, plus hopefully a track-matching fix

frontend/style.css

@@ -447,6 +447,59 @@ tr[draggable="true"]:active { cursor: grabbing; }
     .artist-photo { width: 80px; height: 80px; }
     .scroll-track { width: 18px; }
     .scroll-track-letter { font-size: 0.7rem; }
+    .playlist-controls-row { grid-template-columns: repeat(2, 1fr); }
+}
+
+/* Tooltips */
+.tooltip-wrap {
+    position: relative;
+    display: inline-flex;
+    align-items: center;
+    gap: 0.3rem;
+}
+.tooltip-icon {
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
+    width: 15px;
+    height: 15px;
+    border-radius: 50%;
+    background: var(--border);
+    color: var(--text-muted);
+    font-size: 0.65rem;
+    font-weight: bold;
+    cursor: help;
+    flex-shrink: 0;
+}
+.tooltip-text {
+    visibility: hidden;
+    opacity: 0;
+    position: absolute;
+    bottom: calc(100% + 6px);
+    left: 0;
+    width: 240px;
+    padding: 0.5rem 0.6rem;
+    background: var(--bg-tertiary);
+    color: var(--text-primary);
+    border: 1px solid var(--border);
+    border-radius: 6px;
+    font-size: 0.75rem;
+    line-height: 1.4;
+    z-index: 50;
+    pointer-events: none;
+    transition: opacity 0.15s;
+}
+.tooltip-wrap:hover .tooltip-text {
+    visibility: visible;
+    opacity: 1;
+}
+
+/* Playlist controls row */
+.playlist-controls-row {
+    display: grid;
+    grid-template-columns: repeat(4, 1fr);
+    gap: 1rem;
+    align-items: end;
 }
 
 /* Alphabetical scroll track — fixed to right edge next to browser scrollbar */