diff --git a/index.html b/index.html
index 0936e23..aa5cf71 100644
--- a/index.html
+++ b/index.html
@@ -97,25 +97,20 @@ body {
 <div class="calc">
   <div class="display" id="display">0</div>
   <div class="buttons">
-    <button class="btn btn-clear" id="clear">C</button>
-    <button class="btn btn-op" data-op="±">±</button>
-    <button class="btn btn-op" data-op="%">%</button>
-    <button class="btn btn-op" data-op="÷">÷</button>
-
     <button class="btn btn-num" data-num="7">7</button>
     <button class="btn btn-num" data-num="8">8</button>
     <button class="btn btn-num" data-num="9">9</button>
-    <button class="btn btn-op" data-op="×">×</button>
+    <button class="btn btn-op" data-op="−">−</button>
 
     <button class="btn btn-num" data-num="4">4</button>
     <button class="btn btn-num" data-num="5">5</button>
     <button class="btn btn-num" data-num="6">6</button>
-    <button class="btn btn-op" data-op="−">−</button>
+    <button class="btn btn-op" data-op="+">+</button>
 
     <button class="btn btn-num" data-num="1">1</button>
     <button class="btn btn-num" data-num="2">2</button>
     <button class="btn btn-num" data-num="3">3</button>
-    <button class="btn btn-op" data-op="+">+</button>
+    <button class="btn btn-clear" id="clear">C</button>
 
     <button class="btn btn-num btn-zero" data-num="0">0</button>
     <button class="btn btn-num" data-num=".">.</button>
@@ -149,8 +144,6 @@ document.querySelectorAll('[data-num]').forEach(btn => {
 document.querySelectorAll('[data-op]').forEach(btn => {
   btn.addEventListener('click', () => {
     const op = btn.dataset.op;
-    if (op === '±') { current = String(parseFloat(current) * -1); updateDisplay(current); return; }
-    if (op === '%') { current = String(parseFloat(current) / 100); updateDisplay(current); return; }
     if (previous !== '' && !resetDisplay) compute();
     previous = current;
     operation = op;
@@ -179,14 +172,10 @@ function compute() {
   const b = parseFloat(current);
   if (isNaN(a) || isNaN(b)) return;
   let result;
-  switch (operation) {
-    case '+': result = a + b; break;
-    case '−': result = a - b; break;
-    case '×': result = a * b; break;
-    case '÷': result = b !== 0 ? a / b : 'Ошибка'; break;
-    default: return;
-  }
-  current = typeof result === 'number' ? String(Math.round(result * 1e10) / 1e10) : result;
+  if (operation === '+') result = a + b;
+  else if (operation === '−') result = a - b;
+  else return;
+  current = String(Math.round(result * 1e10) / 1e10);
   updateDisplay(current);
   resetDisplay = true;
 }