diff --git a/src/App.svelte b/src/App.svelte
index cb790cb..4967b2f 100644
--- a/src/App.svelte
+++ b/src/App.svelte
@@ -33,7 +33,26 @@
   const wrapperWidth = $derived(`${slides.all.length * 100}vw`)
   const wrapperTransform = $derived(`translateX(-${slides.activeIndex * 100}vw)`)
 
+  let isReady    = $state(false)
+  let isResizing = $state(false)
+  let resizeTimer = null
+
+  // Active la transition seulement après le premier paint à la bonne position.
+  // Sans ça, un chargement sur /expertise slide depuis l'accueil.
+  $effect(() => {
+    if (slides.all.length > 0 && !isReady) {
+      requestAnimationFrame(() => { isReady = true })
+    }
+  })
+
   onMount(() => {
+    const handleResize = () => {
+      isResizing = true
+      clearTimeout(resizeTimer)
+      resizeTimer = setTimeout(() => { isResizing = false }, 150)
+    }
+    window.addEventListener('resize', handleResize)
+
     const handleKeydown = (e) => {
       if (e.key === 'ArrowRight') {
         const next = slides.all[slides.activeIndex + 1]
@@ -44,7 +63,11 @@
       }
     }
     window.addEventListener('keydown', handleKeydown)
-    return () => window.removeEventListener('keydown', handleKeydown)
+    return () => {
+      window.removeEventListener('resize', handleResize)
+      window.removeEventListener('keydown', handleKeydown)
+      clearTimeout(resizeTimer)
+    }
   })
 </script>
 
@@ -54,6 +77,7 @@
 <main class="main">
   <div
     class="slides-wrapper"
+    class:is-animated={isReady && !isResizing}
     style="width: {wrapperWidth}; transform: {wrapperTransform}"
   >
     {#each slides.all as slide}
@@ -106,6 +130,9 @@
   .slides-wrapper {
     display: flex;
     height: 100%;
+  }
+
+  .slides-wrapper.is-animated {
     transition: transform 1000ms cubic-bezier(0.77, 0, 0.175, 1);
   }