Simplify quote form with expandable details section

Show only name, email and message by default. Detailed fields
(units, connections, VPN, extras) and price calculator open via
"Tarkemmat tiedot & hintalaskuri" button.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

style.css

@@ -1616,12 +1616,6 @@ a:hover {
 }
 
 /* === Calculator Layout === */
-.calculator-layout {
-    display: grid;
-    grid-template-columns: 1fr 360px;
-    gap: 40px;
-    align-items: start;
-}
 
 .calculator-form {
     min-width: 0;
@@ -1661,10 +1655,6 @@ a:hover {
     margin-bottom: 16px;
 }
 
-.calculator-sidebar {
-    position: sticky;
-    top: 100px;
-}
 
 .price-calculator {
     background: var(--color-dark);
@@ -1787,14 +1777,89 @@ a:hover {
     border-top: 1px solid var(--color-border);
 }
 
+/* Expand form button */
+.btn-expand-form {
+    display: flex;
+    align-items: center;
+    gap: 10px;
+    width: 100%;
+    padding: 14px 20px;
+    margin: 8px 0 24px;
+    background: var(--color-bg-alt);
+    border: 1px dashed var(--color-border);
+    border-radius: var(--radius);
+    color: var(--color-text-heading);
+    font-size: 0.95rem;
+    font-weight: 600;
+    cursor: pointer;
+    transition: all 0.2s ease;
+    font-family: inherit;
+}
+.btn-expand-form:hover {
+    border-color: var(--color-primary);
+    color: var(--color-primary);
+    background: rgba(240, 112, 96, 0.04);
+}
+.btn-expand-form .btn-expand-icon {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    width: 26px;
+    height: 26px;
+    border-radius: 50%;
+    background: var(--color-primary);
+    color: var(--color-white);
+    font-size: 1.1rem;
+    font-weight: 700;
+    flex-shrink: 0;
+    transition: transform 0.3s ease;
+}
+.btn-expand-form.expanded .btn-expand-icon {
+    transform: rotate(180deg);
+}
+
+/* Form details (expandable) */
+.form-details {
+    animation: slideDown 0.3s ease;
+}
+@keyframes slideDown {
+    from { opacity: 0; transform: translateY(-10px); }
+    to { opacity: 1; transform: translateY(0); }
+}
+
+/* Calculator sidebar: hidden by default, shown when expanded */
+.calculator-sidebar {
+    display: none;
+}
+.calculator-sidebar.visible {
+    display: block;
+    position: sticky;
+    top: 100px;
+}
+
+/* When sidebar not visible, form takes full width */
+.calculator-layout {
+    display: grid;
+    grid-template-columns: 1fr;
+    gap: 40px;
+    align-items: start;
+}
+.calculator-layout:has(.calculator-sidebar.visible) {
+    grid-template-columns: 1fr 360px;
+}
+
 @media (max-width: 900px) {
-    .calculator-layout {
+    .calculator-layout,
+    .calculator-layout:has(.calculator-sidebar.visible) {
         grid-template-columns: 1fr;
     }
     .calculator-sidebar {
         position: static;
         order: -1;
     }
+    .calculator-sidebar.visible {
+        display: block;
+    }
 }
 
 /* === Animations === */