feat: 动态调整 Toast 提示框的顶部偏移量，优化显示效果

sidepanel/sidepanel.css

@@ -756,7 +756,7 @@ header {
 
 #toast-container {
   position: fixed;
-  top: 12px;
+  top: var(--toast-top-offset, 12px);
   left: 12px;
   right: 12px;
   z-index: 1000;

sidepanel/sidepanel.js

@@ -44,6 +44,7 @@ const btnAutoStartClose = document.getElementById('btn-auto-start-close');
 const btnAutoStartCancel = document.getElementById('btn-auto-start-cancel');
 const btnAutoStartRestart = document.getElementById('btn-auto-start-restart');
 const btnAutoStartContinue = document.getElementById('btn-auto-start-continue');
+const pageHeader = document.querySelector('header');
 const STEP_DEFAULT_STATUSES = {
   1: 'pending',
   2: 'pending',
@@ -113,6 +114,13 @@ function dismissToast(toast) {
   toast.addEventListener('animationend', () => toast.remove());
 }
 
+function updateToastOffset() {
+  if (!toastContainer) return;
+  const headerBottom = pageHeader?.getBoundingClientRect().bottom ?? 0;
+  const offset = Math.max(12, Math.ceil(headerBottom + 8));
+  document.documentElement.style.setProperty('--toast-top-offset', `${offset}px`);
+}
+
 function resetActionModalButtons() {
   const buttons = [btnAutoStartCancel, btnAutoStartRestart, btnAutoStartContinue];
   buttons.forEach((button) => {