diff --git a/index.html b/index.html
index 8175617..fbc0c09 100644
--- a/index.html
+++ b/index.html
@@ -23,15 +23,23 @@
     <main class="shell">
       <section class="hero" aria-labelledby="page-title">
         <div class="hero-content">
+          <button
+            class="settings-button"
+            type="button"
+            aria-label="Открыть настройки внешнего вида"
+            aria-expanded="false"
+            data-settings-toggle
+          >
+            ⚙
+          </button>
+
           <p class="eyebrow">Infrastructure map</p>
           <h1 id="page-title">Панель экосистемы</h1>
           <p class="lead">
             Единая точка входа в пользовательские, административные,
             мониторинговые и инфраструктурные интерфейсы.
           </p>
-        </div>
 
-        <div class="control-panel" aria-label="Настройки панели">
           <label class="search-field">
             <span>Поиск</span>
             <input
@@ -42,80 +50,102 @@
             />
           </label>
 
-          <div class="control-group">
-            <span>Тема</span>
-            <button class="segmented is-active" type="button" data-theme="dark">
-              Темная
-            </button>
-            <button class="segmented" type="button" data-theme="light">
-              Светлая
-            </button>
-          </div>
+          <section class="overview" aria-label="Сводка">
+            <div>
+              <span data-total-sections>0</span>
+              <p>раздела</p>
+            </div>
+            <div>
+              <span data-total-groups>0</span>
+              <p>подразделов</p>
+            </div>
+            <div>
+              <span data-total-items>0</span>
+              <p>элементов</p>
+            </div>
+            <div>
+              <span data-visible-items>0</span>
+              <p>найдено</p>
+            </div>
+          </section>
 
-          <div class="control-group">
-            <span>Вид</span>
-            <button class="segmented is-active" type="button" data-view="cards">
-              Плитки
-            </button>
-            <button class="segmented" type="button" data-view="list">
-              Список
-            </button>
-            <button class="segmented" type="button" data-view="compact-cards">
-              Компакт плитки
-            </button>
-            <button class="segmented" type="button" data-view="compact-list">
-              Компакт список
-            </button>
-          </div>
-
-          <div class="control-group accent-group">
-            <span>Акцент</span>
-            <button
-              class="accent-swatch is-active"
-              type="button"
-              data-accent="violet"
-              aria-label="Фиолетовый акцент"
-            ></button>
-            <button
-              class="accent-swatch"
-              type="button"
-              data-accent="cyan"
-              aria-label="Голубой акцент"
-            ></button>
-            <button
-              class="accent-swatch"
-              type="button"
-              data-accent="lime"
-              aria-label="Лаймовый акцент"
-            ></button>
-            <button
-              class="accent-swatch"
-              type="button"
-              data-accent="amber"
-              aria-label="Янтарный акцент"
-            ></button>
-          </div>
         </div>
       </section>
 
-      <section class="overview" aria-label="Сводка">
-        <div>
-          <span data-total-sections>0</span>
-          <p>раздела</p>
+      <div class="settings-overlay" data-settings-overlay></div>
+      <div class="control-panel" aria-label="Настройки панели" data-settings-panel>
+        <div class="settings-panel-head">
+          <div>
+            <p class="eyebrow">View settings</p>
+            <h2>Настройки</h2>
+          </div>
+          <button class="settings-close" type="button" aria-label="Закрыть настройки" data-settings-close>
+            ×
+          </button>
         </div>
-        <div>
-          <span data-total-groups>0</span>
-          <p>подразделов</p>
+
+        <div class="control-group">
+          <span>Тема</span>
+          <button class="segmented is-active" type="button" data-theme="dark">
+            Темная
+          </button>
+          <button class="segmented" type="button" data-theme="light">
+            Светлая
+          </button>
         </div>
-        <div>
-          <span data-total-items>0</span>
-          <p>элементов</p>
+
+        <div class="control-group">
+          <span>Вид</span>
+          <button class="segmented is-active" type="button" data-view="cards">
+            Плитки
+          </button>
+          <button class="segmented" type="button" data-view="list">
+            Список
+          </button>
+          <button class="segmented" type="button" data-view="compact-cards">
+            Компакт плитки
+          </button>
+          <button class="segmented" type="button" data-view="compact-list">
+            Компакт список
+          </button>
         </div>
-        <div>
-          <span data-visible-items>0</span>
-          <p>найдено</p>
+
+        <label class="toggle-row">
+          <span>
+            <strong>Показывать нумерацию</strong>
+            <small>Разделы, подразделы и элементы</small>
+          </span>
+          <input type="checkbox" data-show-numbers />
+        </label>
+
+        <div class="control-group accent-group">
+          <span>Акцент</span>
+          <button
+            class="accent-swatch is-active"
+            type="button"
+            data-accent="violet"
+            aria-label="Фиолетовый акцент"
+          ></button>
+          <button
+            class="accent-swatch"
+            type="button"
+            data-accent="cyan"
+            aria-label="Голубой акцент"
+          ></button>
+          <button
+            class="accent-swatch"
+            type="button"
+            data-accent="lime"
+            aria-label="Лаймовый акцент"
+          ></button>
+          <button
+            class="accent-swatch"
+            type="button"
+            data-accent="amber"
+            aria-label="Янтарный акцент"
+          ></button>
         </div>
-      </section>
+      </div>
 
       <section class="catalog cards-view" aria-live="polite" data-catalog-root></section>
 
diff --git a/script.js b/script.js
index 54fb7a3..5d0141a 100644
--- a/script.js
+++ b/script.js
@@ -136,15 +136,21 @@ const defaultPreferences = {
   theme: window.matchMedia("(prefers-color-scheme: light)").matches ? "light" : "dark",
   view: "cards",
   accent: "violet",
+  showNumbers: false,
 };
 const availableViews = ["cards", "list", "compact-cards", "compact-list"];
 
 const preferences = { ...defaultPreferences, ...readPreferences() };
 const catalog = document.querySelector("[data-catalog-root]");
 const searchInput = document.querySelector("[data-search-input]");
+const settingsToggle = document.querySelector("[data-settings-toggle]");
+const settingsPanel = document.querySelector("[data-settings-panel]");
+const settingsOverlay = document.querySelector("[data-settings-overlay]");
+const settingsClose = document.querySelector("[data-settings-close]");
 const themeButtons = document.querySelectorAll("[data-theme]");
 const viewButtons = document.querySelectorAll("[data-view]");
 const accentButtons = document.querySelectorAll("[data-accent]");
+const showNumbersInput = document.querySelector("[data-show-numbers]");
 const emptyTemplate = document.querySelector("#empty-template");
 
 const totals = calculateTotals(ecosystemSections);
@@ -157,6 +163,33 @@ renderCatalog();
 
 searchInput.addEventListener("input", renderCatalog);
 
+settingsToggle.addEventListener("click", () => {
+  const isOpen = settingsPanel.classList.toggle("is-open");
+  settingsOverlay.classList.toggle("is-open", isOpen);
+  settingsToggle.setAttribute("aria-expanded", String(isOpen));
+});
+
+settingsClose.addEventListener("click", closeSettingsPanel);
+settingsOverlay.addEventListener("click", closeSettingsPanel);
+
+document.addEventListener("keydown", (event) => {
+  if (event.key === "Escape") {
+    closeSettingsPanel();
+  }
+});
+
+document.addEventListener("click", (event) => {
+  if (!settingsPanel.classList.contains("is-open")) {
+    return;
+  }
+
+  if (settingsPanel.contains(event.target) || settingsToggle.contains(event.target)) {
+    return;
+  }
+
+  closeSettingsPanel();
+});
+
 themeButtons.forEach((button) => {
   button.addEventListener("click", () => {
     preferences.theme = button.dataset.theme;
@@ -181,6 +214,12 @@ accentButtons.forEach((button) => {
   });
 });
 
+showNumbersInput.addEventListener("change", () => {
+  preferences.showNumbers = showNumbersInput.checked;
+  applyPreferences(preferences);
+  savePreferences(preferences);
+});
+
 function createItem(number, title, type, tags = [], url = "#") {
   return { number, title, type, tags, url };
 }
@@ -227,36 +266,44 @@ function renderCatalog() {
 }
 
 function createSectionElement(section) {
-  const sectionElement = document.createElement("article");
+  const sectionElement = document.createElement("details");
   sectionElement.className = "catalog-section";
+  sectionElement.open = true;
   sectionElement.innerHTML = `
-    <header class="section-head">
+    <summary class="section-head">
       <div>
-        <p class="eyebrow">${section.number} раздел</p>
+        <p class="section-number">${section.number} раздел</p>
         <h2>${section.title}</h2>
         <p>${section.description}</p>
       </div>
-      <span class="section-count"><span data-section-count>0</span> элементов</span>
-    </header>
+      <span class="section-meta">
+        <span class="section-count"><span data-section-count>0</span> элементов</span>
+        <span class="collapse-indicator" aria-hidden="true">⌄</span>
+      </span>
+    </summary>
     <div class="section-groups"></div>
   `;
   return sectionElement;
 }
 
 function createGroupElement(group, items) {
-  const groupElement = document.createElement("section");
+  const groupElement = document.createElement("details");
   groupElement.className = "catalog-group";
+  groupElement.open = true;
 
   const cards = items.map(createCardElement);
   groupElement.innerHTML = `
-    <header class="group-head">
+    <summary class="group-head">
       <div>
         <p class="group-number">${group.number}</p>
         <h3>${group.title}</h3>
         <p>${group.description}</p>
       </div>
-      <span>${items.length}</span>
-    </header>
+      <span class="group-meta">
+        <span class="group-count">${items.length}</span>
+        <span class="collapse-indicator" aria-hidden="true">⌄</span>
+      </span>
+    </summary>
   `;
 
   const grid = document.createElement("div");
@@ -364,6 +411,8 @@ function applyPreferences(nextPreferences) {
   document.documentElement.dataset.accent = nextPreferences.accent;
   catalog.classList.remove("cards-view", "list-view", "compact-cards-view", "compact-list-view");
   catalog.classList.add(`${nextPreferences.view}-view`);
+  document.documentElement.dataset.showNumbers = String(Boolean(nextPreferences.showNumbers));
+  showNumbersInput.checked = Boolean(nextPreferences.showNumbers);
   setActiveButton(themeButtons, "theme", nextPreferences.theme);
   setActiveButton(viewButtons, "view", nextPreferences.view);
   setActiveButton(accentButtons, "accent", nextPreferences.accent);
@@ -408,3 +457,9 @@ function readPreferences() {
 function savePreferences(nextPreferences) {
   localStorage.setItem(STORAGE_KEY, JSON.stringify(nextPreferences));
 }
+
+function closeSettingsPanel() {
+  settingsPanel.classList.remove("is-open");
+  settingsOverlay.classList.remove("is-open");
+  settingsToggle.setAttribute("aria-expanded", "false");
+}
diff --git a/styles.css b/styles.css
index 08eeb77..cf411d3 100644
--- a/styles.css
+++ b/styles.css
@@ -104,20 +104,16 @@ a {
 .shell {
   width: min(1320px, calc(100% - 32px));
   margin: 0 auto;
-  padding: 42px 0;
+  padding: 28px 0;
 }
 
 .hero {
-  display: grid;
-  grid-template-columns: minmax(0, 1fr) minmax(330px, 460px);
-  gap: 24px;
-  align-items: stretch;
+  display: block;
   margin-bottom: 18px;
 }
 
 .hero-content,
 .control-panel,
-.overview,
 .catalog-section,
 .empty-state {
   border: 1px solid var(--border);
@@ -127,23 +123,25 @@ a {
 }
 
 .hero-content {
-  min-height: 330px;
+  min-height: 210px;
   display: flex;
   flex-direction: column;
-  justify-content: flex-end;
-  padding: clamp(28px, 5vw, 56px);
-  border-radius: 38px;
+  justify-content: center;
+  gap: 10px;
+  padding: clamp(18px, 3vw, 28px);
+  border-radius: 26px;
   position: relative;
-  overflow: hidden;
+  overflow: visible;
 }
 
 .hero-content::before {
   content: "";
   position: absolute;
   inset: 0;
+  border-radius: inherit;
   background:
-    linear-gradient(120deg, rgba(var(--accent-rgb), 0.28), transparent 34%),
-    url("data:image/svg+xml,%3Csvg width='140' height='140' viewBox='0 0 140 140' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' stroke='white' stroke-opacity='.09'%3E%3Cpath d='M0 70h140M70 0v140'/%3E%3Ccircle cx='70' cy='70' r='38'/%3E%3C/g%3E%3C/svg%3E");
+    linear-gradient(120deg, rgba(var(--accent-rgb), 0.25), transparent 34%),
+    url("data:image/svg+xml,%3Csvg width='96' height='84' viewBox='0 0 96 84' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' stroke='white' stroke-opacity='.10' stroke-width='1.4'%3E%3Cpath d='M24 2 46 14v25L24 52 2 39V14L24 2Z'/%3E%3Cpath d='M72 32 94 44v25L72 82 50 69V44l22-12Z'/%3E%3C/g%3E%3C/svg%3E");
   mask-image: linear-gradient(to bottom, black, transparent 88%);
   pointer-events: none;
 }
@@ -153,6 +151,7 @@ a {
 }
 
 .eyebrow,
+.section-number,
 .group-number,
 .item-number {
   margin: 0;
@@ -165,30 +164,129 @@ a {
 
 h1 {
   max-width: 840px;
-  margin: 14px 0 18px;
-  font-size: clamp(2.6rem, 8vw, 6.4rem);
-  line-height: 0.9;
-  letter-spacing: -0.08em;
+  margin: 4px 0 0;
+  font-size: clamp(1.9rem, 4.4vw, 3.7rem);
+  line-height: 0.98;
+  letter-spacing: -0.07em;
 }
 
 .lead {
   max-width: 740px;
   margin: 0;
   color: var(--muted);
-  font-size: clamp(1rem, 2vw, 1.2rem);
-  line-height: 1.7;
+  font-size: clamp(0.9rem, 1.25vw, 1rem);
+  line-height: 1.5;
+}
+
+html:not([data-show-numbers="true"]) .section-number,
+html:not([data-show-numbers="true"]) .group-number,
+html:not([data-show-numbers="true"]) .item-number {
+  display: none;
 }
 
 .control-panel {
+  position: fixed;
+  z-index: 1001;
+  top: 24px;
+  right: 24px;
+  width: min(460px, calc(100% - 48px));
+  max-height: calc(100vh - 48px);
+  overflow: auto;
   display: grid;
   gap: 14px;
   padding: 18px;
-  border-radius: 28px;
+  border-radius: 24px;
+  opacity: 0;
+  visibility: hidden;
+  pointer-events: none;
+  transform: translateY(-8px) scale(0.98);
+  transform-origin: top right;
+  transition:
+    opacity 180ms ease,
+    visibility 180ms ease,
+    transform 180ms ease;
+}
+
+.settings-overlay {
+  position: fixed;
+  inset: 0;
+  z-index: 1000;
+  background: rgba(2, 6, 23, 0.42);
+  opacity: 0;
+  visibility: hidden;
+  pointer-events: none;
+  backdrop-filter: blur(4px);
+  transition: opacity 180ms ease, visibility 180ms ease;
+}
+
+.settings-overlay.is-open {
+  opacity: 1;
+  visibility: visible;
+  pointer-events: auto;
+}
+
+.control-panel.is-open {
+  opacity: 1;
+  visibility: visible;
+  pointer-events: auto;
+  transform: translateY(0) scale(1);
+}
+
+.settings-button,
+.settings-close {
+  border: 1px solid var(--border);
+  cursor: pointer;
+  color: var(--text);
+  background: var(--surface);
+  transition: transform 160ms ease, background 160ms ease, border-color 160ms ease;
+}
+
+.settings-button {
+  position: absolute;
+  z-index: 21;
+  top: 20px;
+  right: 20px;
+  width: 40px;
+  height: 40px;
+  display: grid;
+  place-items: center;
+  border-radius: 999px;
+  font-size: 1.18rem;
+}
+
+.settings-button:hover,
+.settings-close:hover {
+  transform: translateY(-1px);
+  border-color: rgba(var(--accent-rgb), 0.5);
+  background: rgba(var(--accent-rgb), 0.12);
+}
+
+.settings-panel-head {
+  display: flex;
+  justify-content: space-between;
+  gap: 14px;
+  align-items: flex-start;
+}
+
+.settings-panel-head h2 {
+  margin: 4px 0 0;
+  font-size: 1.35rem;
+  letter-spacing: -0.04em;
+}
+
+.settings-close {
+  width: 34px;
+  height: 34px;
+  flex: 0 0 auto;
+  border-radius: 999px;
+  font-size: 1.25rem;
+  line-height: 1;
 }
 
 .search-field {
   display: grid;
-  gap: 8px;
+  gap: 6px;
+  max-width: 720px;
 }
 
 .search-field span,
@@ -200,9 +298,9 @@ h1 {
 
 .search-field input {
   width: 100%;
-  min-height: 48px;
+  min-height: 42px;
   border: 1px solid var(--border);
-  border-radius: 16px;
+  border-radius: 14px;
   background: var(--surface);
   color: var(--text);
   outline: none;
@@ -216,6 +314,66 @@ h1 {
   background: var(--panel-strong);
 }
 
+.toggle-row {
+  display: flex;
+  justify-content: space-between;
+  gap: 14px;
+  align-items: center;
+  min-height: 54px;
+  padding: 10px 12px;
+  border: 1px solid var(--border);
+  border-radius: 18px;
+  background: var(--surface);
+}
+
+.toggle-row span {
+  display: grid;
+  gap: 2px;
+}
+
+.toggle-row strong {
+  font-size: 0.9rem;
+}
+
+.toggle-row small {
+  color: var(--muted);
+  font-weight: 700;
+}
+
+.toggle-row input {
+  appearance: none;
+  width: 48px;
+  height: 28px;
+  flex: 0 0 auto;
+  border: 1px solid var(--border);
+  border-radius: 999px;
+  background: rgba(148, 163, 184, 0.26);
+  cursor: pointer;
+  position: relative;
+  transition: background 160ms ease, border-color 160ms ease;
+}
+
+.toggle-row input::before {
+  content: "";
+  position: absolute;
+  top: 3px;
+  left: 3px;
+  width: 20px;
+  height: 20px;
+  border-radius: 999px;
+  background: white;
+  transition: transform 160ms ease;
+}
+
+.toggle-row input:checked {
+  border-color: rgba(var(--accent-rgb), 0.6);
+  background: linear-gradient(135deg, var(--accent), var(--accent-2));
+}
+
+.toggle-row input:checked::before {
+  transform: translateX(20px);
+}
+
 .control-group {
   display: flex;
   align-items: center;
@@ -297,28 +455,34 @@ h1 {
   display: grid;
   grid-template-columns: repeat(4, minmax(0, 1fr));
   gap: 1px;
-  margin-bottom: 18px;
-  border-radius: 26px;
+  max-width: 620px;
+  margin-top: 0;
+  border: 1px solid var(--border);
+  border-radius: 16px;
+  background: rgba(255, 255, 255, 0.035);
   overflow: hidden;
 }
 
 .overview div {
-  padding: 18px 20px;
+  padding: 8px 10px;
   background: rgba(255, 255, 255, 0.035);
 }
 
 .overview span {
   display: block;
-  font-size: clamp(1.8rem, 4vw, 2.8rem);
+  font-size: clamp(1rem, 1.8vw, 1.35rem);
   font-weight: 850;
   line-height: 1;
   letter-spacing: -0.06em;
 }
 
 .overview p {
-  margin: 8px 0 0;
+  margin: 4px 0 0;
   color: var(--muted);
   font-weight: 700;
+  font-size: 0.68rem;
+  letter-spacing: 0.02em;
+  text-transform: uppercase;
 }
 
 .catalog {
@@ -331,6 +495,22 @@ h1 {
   overflow: hidden;
 }
 
+.catalog-section,
+.catalog-group {
+  display: block;
+}
+
+.catalog-section > summary,
+.catalog-group > summary {
+  list-style: none;
+  cursor: pointer;
+}
+
+.catalog-section > summary::-webkit-details-marker,
+.catalog-group > summary::-webkit-details-marker {
+  display: none;
+}
+
 .section-head {
   display: flex;
   justify-content: space-between;
@@ -343,6 +523,14 @@ h1 {
     rgba(255, 255, 255, 0.035);
 }
 
+.section-meta,
+.group-meta {
+  display: inline-flex;
+  align-items: center;
+  gap: 8px;
+  flex: 0 0 auto;
+}
+
 .section-head h2,
 .group-head h3,
 .nav-card h4,
@@ -357,7 +545,7 @@ h1 {
   font-size: clamp(1.6rem, 4vw, 2.6rem);
 }
 
-.section-head p:not(.eyebrow),
+.section-head p:not(.section-number),
 .group-head p:not(.group-number) {
   max-width: 760px;
   margin: 8px 0 0;
@@ -376,6 +564,24 @@ h1 {
   font-weight: 800;
 }
 
+.collapse-indicator {
+  width: 34px;
+  height: 34px;
+  display: grid;
+  place-items: center;
+  border: 1px solid var(--border);
+  border-radius: 999px;
+  background: var(--surface);
+  color: var(--accent);
+  font-weight: 900;
+  transition: transform 160ms ease;
+}
+
+.catalog-section:not([open]) > .section-head .collapse-indicator,
+.catalog-group:not([open]) > .group-head .collapse-indicator {
+  transform: rotate(-90deg);
+}
+
 .section-groups {
   display: grid;
   gap: 18px;
@@ -402,7 +608,7 @@ h1 {
   font-size: 1.22rem;
 }
 
-.group-head > span {
+.group-count {
   width: 36px;
   height: 36px;
   display: grid;
@@ -589,8 +795,8 @@ h1 {
   padding: 18px 20px;
 }
 
-.catalog.compact-cards-view .section-head p:not(.eyebrow),
-.catalog.compact-list-view .section-head p:not(.eyebrow),
+.catalog.compact-cards-view .section-head p:not(.section-number),
+.catalog.compact-list-view .section-head p:not(.section-number),
 .catalog.compact-cards-view .group-head p:not(.group-number),
 .catalog.compact-list-view .group-head p:not(.group-number),
 .catalog.compact-cards-view .tags,
@@ -681,10 +887,6 @@ h1 {
 }
 
 @media (max-width: 1120px) {
-  .hero {
-    grid-template-columns: 1fr;
-  }
-
   .items-grid {
     grid-template-columns: repeat(2, minmax(0, 1fr));
   }
@@ -701,8 +903,9 @@ h1 {
   }
 
   .hero-content {
-    min-height: 300px;
-    border-radius: 28px;
+    min-height: auto;
+    padding: 22px 16px;
+    border-radius: 24px;
   }
 
   .control-panel,
@@ -711,6 +914,13 @@ h1 {
     border-radius: 24px;
   }
 
+  .control-panel {
+    top: 12px;
+    right: 12px;
+    width: calc(100vw - 24px);
+    max-height: calc(100vh - 24px);
+  }
+
   .control-group {
     flex-wrap: wrap;
   }