diff --git a/CHANGELOG.md b/CHANGELOG.md
index bd6c3bc..b6b17f6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,4 +3,5 @@
 ### 🚀 Features
 
 - Added changelog
+- Added Themes
 ## [0.1.0] - 2026-09-23
diff --git a/src/main.js b/src/main.js
index bce5afe..979b8a2 100644
--- a/src/main.js
+++ b/src/main.js
@@ -19,7 +19,7 @@ var theme = (() => {
     }
     try {
       localStorage.setItem(STORAGE_KEY, name);
-    } catch (e) {}
+    } catch (e) { }
   }
 
   function init() {
@@ -28,7 +28,7 @@ var theme = (() => {
 
     var picker = document.getElementById('theme-picker');
     picker.value = saved;
-    picker.addEventListener('change', function() {
+    picker.addEventListener('change', function () {
       set(picker.value);
     });
   }
@@ -39,12 +39,18 @@ var theme = (() => {
   return { init };
 })();
 const table = (() => {
+  var dirty = false;
+  var flushTimer = null;
+  var ipIndex = {};
   let data = [];
   let filtered = [];
   let sortKey = 'ip';
   let sortDir = 'asc';
   let filterText = '';
   let checkedIps = new Set();
+  var ROW_HEIGHT = 32;
+  var BUFFER_ROWS = 20;
+  var scrollContainer = null;
 
   function ipToNum(ip) {
     const parts = String(ip).split('.');
@@ -193,20 +199,61 @@ const table = (() => {
   }
 
   function render() {
-    const tbody = document.getElementById('results-body');
-    const count = document.getElementById('host-count');
+    var tbody = document.getElementById('results-body');
+    var count = document.getElementById('host-count');
     if (!tbody) return;
+
     expandedIp = null;
 
-    const rows = filtered.map((host) => {
-      const ip = host.ip;
-      const status = host.status || 'Unknown';
-      const cls = 'status-' + status.toLowerCase();
-      const rtt = host.ping ? host.ping.rtt_ms.toFixed(1) : '-';
-      const hostname = host.hostname || '-';
+    if (!scrollContainer) {
+      scrollContainer = document.getElementById('results-table-container');
+      scrollContainer.addEventListener('scroll', onScroll);
+    }
 
-      const isChecked = checkedIps.has(ip) ? 'checked' : '';
-      return '<tr data-ip="' + ip + '">'
+    renderVisible();
+
+    if (count) {
+      var up = data.filter(function (h) { return h.status === 'Up'; }).length;
+      count.textContent = up + ' up / ' + data.length + ' total';
+    }
+
+    if (columns && columns.apply) columns.apply();
+  }
+
+  function renderVisible() {
+    var tbody = document.getElementById('results-body');
+    if (!tbody || !scrollContainer) return;
+
+    var totalRows = filtered.length;
+    var viewHeight = scrollContainer.clientHeight;
+    var scrollTop = scrollContainer.scrollTop;
+    var headerHeight = 36;
+
+    var startIdx = Math.max(0, Math.floor((scrollTop - headerHeight) / ROW_HEIGHT) - BUFFER_ROWS);
+    var visibleCount = Math.ceil(viewHeight / ROW_HEIGHT) + (BUFFER_ROWS * 2);
+    var endIdx = Math.min(totalRows, startIdx + visibleCount);
+
+    var topSpace = startIdx * ROW_HEIGHT;
+    var bottomSpace = (totalRows - endIdx) * ROW_HEIGHT;
+
+    var colCount = document.querySelectorAll('#results-table th').length;
+
+    var html = '';
+
+    if (topSpace > 0) {
+      html += '<tr class="virtual-spacer"><td colspan="' + colCount + '" style="height:' + topSpace + 'px"></td></tr>';
+    }
+
+    for (var i = startIdx; i < endIdx; i++) {
+      var host = filtered[i];
+      var ip = host.ip;
+      var status = host.status || 'Unknown';
+      var cls = 'status-' + status.toLowerCase();
+      var rtt = host.ping ? host.ping.rtt_ms.toFixed(1) : '-';
+      var hostname = host.hostname || '-';
+      var isChecked = checkedIps.has(ip) ? 'checked' : '';
+
+      html += '<tr data-ip="' + ip + '">'
         + '<td class="col-check"><input type="checkbox" class="row-check" ' + isChecked + ' /></td>'
         + '<td>' + ip + '</td>'
         + '<td class="' + cls + '">' + status + '</td>'
@@ -214,24 +261,43 @@ const table = (() => {
         + '<td>' + hostname + '</td>'
         + '<td class="ports-cell">' + formatPorts(host) + '</td>'
         + '</tr>';
-    });
-
-    tbody.innerHTML = rows.join('');
-
-    if (count) {
-      const up = data.filter((h) => h.status === 'Up').length;
-      count.textContent = up + ' up / ' + data.length + ' total';
     }
-    if (columns && columns.apply) columns.apply();
+
+    if (bottomSpace > 0) {
+      html += '<tr class="virtual-spacer"><td colspan="' + colCount + '" style="height:' + bottomSpace + 'px"></td></tr>';
+    }
+
+    tbody.innerHTML = html;
+  }
+
+  var scrollTimeout = null;
+  function onScroll() {
+    if (scrollTimeout) return;
+    scrollTimeout = requestAnimationFrame(function () {
+      scrollTimeout = null;
+      renderVisible();
+      if (columns && columns.apply) columns.apply();
+    });
   }
 
   function upsert(host) {
-    const idx = data.findIndex((h) => h.ip === host.ip);
+    var idx = data.findIndex(function (h) { return h.ip === host.ip; });
     if (idx >= 0) {
       data[idx] = host;
     } else {
+      ipIndex[host.ip] = data.length;
       data.push(host);
     }
+    dirty = true;
+    if (!flushTimer) {
+      flushTimer = setTimeout(flush, 200);
+    }
+  }
+
+  function flush() {
+    flushTimer = null;
+    if (!dirty) return;
+    dirty = false;
     refresh();
   }
 
@@ -239,6 +305,7 @@ const table = (() => {
     data = [];
     filtered = [];
     checkedIps.clear();
+    ipIndex = {};
     document.getElementById('check-all').checked = false;
     refresh();
   }
@@ -1061,7 +1128,7 @@ var updater = (() => {
   return { init };
 })();
 var changelog = (() => {
-  var modal = function() { return document.getElementById('changelog-modal'); };
+  var modal = function () { return document.getElementById('changelog-modal'); };
   var loaded = false;
 
   async function open() {
@@ -1085,11 +1152,11 @@ var changelog = (() => {
     document.getElementById('btn-changelog').addEventListener('click', open);
     document.getElementById('changelog-close').addEventListener('click', close);
 
-    modal().addEventListener('click', function(e) {
+    modal().addEventListener('click', function (e) {
       if (e.target === modal()) close();
     });
 
-    document.addEventListener('keydown', function(e) {
+    document.addEventListener('keydown', function (e) {
       if (e.key === 'Escape' && modal().classList.contains('visible')) close();
     });
   }
diff --git a/src/styles.css b/src/styles.css
index 85b6be5..5cc067f 100644
--- a/src/styles.css
+++ b/src/styles.css
@@ -409,6 +409,7 @@ body {
   white-space: nowrap;
   overflow: hidden;
   text-overflow: ellipsis;
+  height: 32px;
 }
 
 #results-table tbody tr {
@@ -428,6 +429,15 @@ body {
   box-shadow: inset 3px 0 0 var(--cyan);
 }
 
+.virtual-spacer {
+  border: none !important;
+}
+
+.virtual-spacer td {
+  padding: 0 !important;
+  border: none !important;
+}
+
 /* ===== Status Colors ===== */
 
 .status-up {
@@ -1322,6 +1332,7 @@ body {
 .changelog-content a:hover {
   text-decoration: underline;
 }
+
 .theme-picker {
   padding: 1px 6px;
   font-size: 11px;
@@ -1345,6 +1356,7 @@ body {
   background: var(--bg-secondary);
   color: var(--text-primary);
 }
+
 /* ===== Theme: Midnight ===== */
 
 :root[data-theme="midnight"] {