Apply ten iterative posts UI improvements

web/style.css

@@ -4,6 +4,22 @@
   box-sizing: border-box;
 }
 
+@media (prefers-reduced-motion: reduce) {
+  .tab-btn,
+  .search-clear-btn,
+  .posts-scroll-top,
+  .post-card,
+  .auto-open-overlay,
+  .auto-open-overlay__panel {
+    transition: none;
+  }
+
+  .post-card--highlight {
+    animation: none;
+    box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.45);
+  }
+}
+
 :root {
   --content-max-width: 1300px;
   --top-gap: 12px;
@@ -302,6 +318,27 @@ header {
   align-items: center;
 }
 
+.search-field__hint {
+  margin: 0;
+  font-size: 11px;
+  color: #64748b;
+  line-height: 1.35;
+}
+
+.search-field__hint kbd {
+  display: inline-block;
+  min-width: 18px;
+  padding: 1px 6px;
+  border-radius: 6px;
+  border: 1px solid #cbd5e1;
+  background: #f8fafc;
+  color: #0f172a;
+  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
+  font-size: 11px;
+  font-weight: 700;
+  text-align: center;
+}
+
 .search-clear-btn {
   position: absolute;
   right: 6px;
@@ -806,6 +843,34 @@ h1 {
   gap: 6px;
 }
 
+.posts-scroll-top {
+  position: fixed;
+  right: 20px;
+  bottom: 20px;
+  width: 42px;
+  height: 42px;
+  border: none;
+  border-radius: 999px;
+  background: #0f172a;
+  color: #fff;
+  font-size: 22px;
+  line-height: 1;
+  cursor: pointer;
+  box-shadow: 0 10px 24px rgba(15, 23, 42, 0.28);
+  z-index: 45;
+  transition: transform 0.2s ease, background-color 0.2s ease;
+}
+
+.posts-scroll-top:hover {
+  background: #1d4ed8;
+  transform: translateY(-2px);
+}
+
+.posts-scroll-top:focus-visible {
+  outline: 2px solid #1d4ed8;
+  outline-offset: 2px;
+}
+
 .post-card {
   position: relative;
   background: white;
@@ -2260,6 +2325,10 @@ h1 {
     min-width: 100%;
   }
 
+  .search-field__hint {
+    font-size: 10px;
+  }
+
   .bulk-actions {
     flex-direction: column;
     align-items: stretch;
@@ -2455,7 +2524,15 @@ h1 {
     justify-content: flex-start;
   }
 
+  .search-filter-toggle {
+    order: 2;
+    width: 100%;
+    justify-content: flex-start;
+  }
+
   .search-field {
+    order: 1;
+    width: 100%;
     flex: 1 1 260px;
   }
 
@@ -2472,6 +2549,12 @@ h1 {
 
   .bulk-status {
     width: 100%;
+    justify-content: flex-start;
+  }
+
+  .posts-scroll-top {
+    right: 14px;
+    bottom: 14px;
   }
 
   .form-actions {