diff --git a/css/style.css b/css/style.css
index 7903e63..e429488 100644
--- a/css/style.css
+++ b/css/style.css
@@ -1388,6 +1388,44 @@ a.ms1-trad-link.btn-aide-trad{
     padding:10px;
     font-weight:bold;
 }
+
+.epr-header--collapsible{
+    display:flex;
+    align-items:center;
+    justify-content:space-between;
+    gap:10px;
+}
+
+.epr-header--collapsible .epr-header-label{
+    flex:1;
+    min-width:0;
+}
+
+.epr-block-toggle{
+    flex-shrink:0;
+    width:28px;
+    height:28px;
+    padding:0;
+    border:1px solid rgba(255,255,255,.55);
+    border-radius:4px;
+    background:rgba(255,255,255,.12);
+    color:#fff;
+    font-size:13px;
+    line-height:1;
+    cursor:pointer;
+}
+
+.epr-block-toggle:hover,
+.epr-block-toggle:focus{
+    background:rgba(255,255,255,.22);
+    color:#fff;
+    outline:none;
+}
+
+.epr-block.is-collapsed .epr-content{
+    display:none;
+}
+
 .bib-container .batch-checkbox{
     display:none;
 }
diff --git a/inc_footer_scripts.php b/inc_footer_scripts.php
index 24e0568..b97bd06 100644
--- a/inc_footer_scripts.php
+++ b/inc_footer_scripts.php
@@ -1959,6 +1959,32 @@ if ($strLangue == 'fr') {
 
         if (moduleBib) {
 
+            // MSIN-4379 — Réduire / développer les blocs gestion et assignation (en-tête seul visible).
+            moduleBib.addEventListener('click', function (e) {
+                let btnToggle = e.target.closest('.epr-block-toggle');
+                if (!btnToggle || !moduleBib.contains(btnToggle)) {
+                    return;
+                }
+                let block = btnToggle.closest('.epr-block');
+                if (!block) {
+                    return;
+                }
+                let collapsed = block.classList.toggle('is-collapsed');
+                btnToggle.setAttribute('aria-expanded', collapsed ? 'false' : 'true');
+                let label = collapsed
+                    ? (btnToggle.getAttribute('data-label-expand') || '')
+                    : (btnToggle.getAttribute('data-label-collapse') || '');
+                if (label) {
+                    btnToggle.setAttribute('aria-label', label);
+                    btnToggle.setAttribute('title', label);
+                }
+                let icon = btnToggle.querySelector('.fa');
+                if (icon) {
+                    icon.classList.toggle('fa-chevron-up', !collapsed);
+                    icon.classList.toggle('fa-chevron-down', collapsed);
+                }
+            });
+
             // ============================================================
             // MSIN-4379 — Tippy.js (module #module-bib uniquement)
             // info_texte → data-tippy-content (tip court)
diff --git a/php/inc_fx_promoteur.php b/php/inc_fx_promoteur.php
index 3946e7b..c32399a 100644
--- a/php/inc_fx_promoteur.php
+++ b/php/inc_fx_promoteur.php
@@ -2830,6 +2830,19 @@ function fxBibBlockHeader($clef, $strFallback = '', $docAnchorClef = '') {
     return $html . '</span>';
 }
 
+/** Bouton réduire / développer le corps du bloc (en-tête reste visible). */
+function fxBibBlockCollapseToggle($strLangue = 'fr') {
+    $strCollapse = ($strLangue === 'en') ? 'Collapse section' : 'Réduire la section';
+    $strExpand = ($strLangue === 'en') ? 'Expand section' : 'Développer la section';
+
+    return '<button type="button" class="epr-block-toggle" aria-expanded="true"'
+        . ' data-label-collapse="' . fxBibEsc($strCollapse) . '"'
+        . ' data-label-expand="' . fxBibEsc($strExpand) . '"'
+        . ' aria-label="' . fxBibEsc($strCollapse) . '"'
+        . ' title="' . fxBibEsc($strCollapse) . '">'
+        . '<i class="fa fa-chevron-up" aria-hidden="true"></i></button>';
+}
+
 /** Cellule d'en-tête de colonne séquence + aide optionnelle (info_texte peut être vide). */
 function fxBibColHeader($clef, $strFallback = '') {
     $strLabel = fxBibTexte($clef, 0, $strFallback, true);
@@ -3187,7 +3200,10 @@ if ($teamMode <= 0) {
                 <div class="epr-col-right">
                     <?php /* MSIN-4379 — Gestion des épreuves : quantités et paramètres (distinct de l'assignation de dossard). */ ?>
                     <div class="epr-block epr-block-gestion">
-                        <div class="epr-header"><?php echo fxBibBlockHeader('bib_v4_gestion_title', 'Gestion des épreuves'); ?></div>
+                        <div class="epr-header epr-header--collapsible">
+                            <?php echo fxBibBlockHeader('bib_v4_gestion_title', 'Gestion des épreuves'); ?>
+                            <?php echo fxBibBlockCollapseToggle($strLangue); ?>
+                        </div>
                         <div class="epr-content">
                             <?php echo renderBibGestionEpreuve((int)$tabEpreuves[$i]['epr_id'], (int)$int_eve_id, $strLangue); ?>
                         </div>
@@ -3195,7 +3211,10 @@ if ($teamMode <= 0) {
 
                     <?php /* MSIN-4379 — Assignation de dossard : séquences + actions (ex 3e colonne). */ ?>
                     <div class="epr-block epr-block-assign">
-                        <div class="epr-header"><?php echo fxBibBlockHeader('bib_v4_assign_title', 'Assignation de dossard', 'bib_v4_assign_doc'); ?></div>
+                        <div class="epr-header epr-header--collapsible">
+                            <?php echo fxBibBlockHeader('bib_v4_assign_title', 'Assignation de dossard', 'bib_v4_assign_doc'); ?>
+                            <?php echo fxBibBlockCollapseToggle($strLangue); ?>
+                        </div>
                         <div class="epr-content">
 
                     <?php if (count($tabBibStats) == 0) { ?>
diff --git a/php/inc_settings.php b/php/inc_settings.php
index 8d84643..afefecc 100644
--- a/php/inc_settings.php
+++ b/php/inc_settings.php
@@ -7,7 +7,7 @@
  * Constantes *
  *
  **************/
-define('_VERSION_CODE', '4.72.650');
+define('_VERSION_CODE', '4.72.651');
 define('_DATE_CODE', '2026-06-17');
 //MSIN-4290
 define('QR_SECRET_KEY', 'ms1_qr_2026_cle_secrete_longue_et_fixe');