feat: tune visual of install instructions page

frontend/src/styles/webapp.css

@@ -2013,6 +2013,43 @@ a {
   animation: toast-enter 0.22s ease-out both;
 }
 
+.motion-height-stage {
+  display: grid;
+  align-content: start;
+  min-width: 0;
+}
+
+.motion-height-stage.motion-height-locked {
+  overflow: hidden;
+  transition: height var(--motion-stage-duration, 360ms) cubic-bezier(0.22, 0.72, 0.2, 1);
+  will-change: height;
+}
+
+.motion-height-stage.motion-height-instant {
+  transition: none;
+}
+
+.motion-enter-card {
+  animation: motion-card-enter var(--motion-enter-duration, 340ms) cubic-bezier(0.22, 0.72, 0.2, 1)
+    backwards;
+  animation-delay: var(--motion-delay, 0ms);
+  transform-origin: var(--motion-origin, center top);
+  will-change: opacity, transform;
+}
+
+.motion-fade-up {
+  animation: motion-fade-up var(--motion-enter-duration, 160ms) ease-out both;
+}
+
+.motion-scale-in {
+  animation: motion-scale-in var(--motion-enter-duration, 240ms) cubic-bezier(0.22, 0.72, 0.2, 1)
+    both;
+}
+
+.motion-shimmer {
+  animation: motion-shimmer var(--motion-shimmer-duration, 1.15s) ease-in-out infinite;
+}
+
 @keyframes section-enter {
   from {
     opacity: 0;
@@ -2037,6 +2074,56 @@ a {
   }
 }
 
+@keyframes motion-card-enter {
+  from {
+    opacity: 0;
+    transform: translate3d(0, 12px, 0) scale(0.985);
+  }
+
+  70% {
+    opacity: 1;
+  }
+
+  to {
+    opacity: 1;
+    transform: translate3d(0, 0, 0) scale(1);
+  }
+}
+
+@keyframes motion-fade-up {
+  from {
+    opacity: 0;
+    transform: translateY(4px);
+  }
+
+  to {
+    opacity: 1;
+    transform: translateY(0);
+  }
+}
+
+@keyframes motion-scale-in {
+  from {
+    opacity: 0;
+    transform: scale(0.975);
+  }
+
+  to {
+    opacity: 1;
+    transform: scale(1);
+  }
+}
+
+@keyframes motion-shimmer {
+  0% {
+    background-position: 120% 0;
+  }
+
+  100% {
+    background-position: -120% 0;
+  }
+}
+
 @keyframes toast-enter {
   from {
     opacity: 0;
@@ -2234,11 +2321,16 @@ a {
   .dialog-backdrop,
   .dialog-card,
   .auth-mode-panel,
+  .motion-enter-card,
+  .motion-fade-up,
+  .motion-scale-in,
+  .motion-shimmer,
   .toast {
     animation: none !important;
   }
 
-  .auth-card {
+  .auth-card,
+  .motion-height-stage.motion-height-locked {
     transition: none !important;
   }
 }