diff --git a/TODO.md b/TODO.md
index a73c465..016ec22 100644
--- a/TODO.md
+++ b/TODO.md
@@ -34,3 +34,8 @@
 - [x] Relax 3-keyword minimum: admin mode (create) requires 1+, edit requires 1+, student (partage) requires 3
 - [x] Add CSS for file preview items (.fp-item, .fp-thumb, .fp-icon, .fp-meta, .fp-name, .fp-size) so annexes/cover/note-intention previews wrap and display correctly
 - [x] Fix TFE file input accept attribute to include video/audio/archive extensions
+- [x] Make annexes file input required when "Ce TFE comporte des annexes" is checked
+- [x] Add PHP-side validation: if has_annexes checked but no annexe files provided, throw error
+- [x] Add HTMX inline file validation: MIME type + file size checked on change via validate-file-fragment endpoint
+- [x] Create shared validation logic (validate-file-fragment-shared.php) used by both admin and partage
+- [x] Add CSS for .file-validation-msg, .fv-ok, .fv-error inline validation messages
diff --git a/app/public/admin/validate-file-fragment.php b/app/public/admin/validate-file-fragment.php
new file mode 100644
index 0000000..6369462
--- /dev/null
+++ b/app/public/admin/validate-file-fragment.php
@@ -0,0 +1,12 @@
+<?php
+/**
+ * validate-file-fragment.php (admin)
+ *
+ * Admin-gated HTMX fragment: validates uploaded file MIME type and size.
+ * Wraps the shared validation logic.
+ */
+require_once __DIR__ . '/../../bootstrap.php';
+require_once __DIR__ . '/../../src/AdminAuth.php';
+AdminAuth::requireLogin();
+
+require_once APP_ROOT . '/src/Controllers/validate-file-fragment-shared.php';
diff --git a/app/public/assets/css/form.css b/app/public/assets/css/form.css
index 9a7b8f6..2073639 100644
--- a/app/public/assets/css/form.css
+++ b/app/public/assets/css/form.css
@@ -516,6 +516,22 @@
   color: var(--text-tertiary);
 }
 
+/* ── Inline file validation messages (HTMX) ──────────────────────────────── */
+
+.file-validation-msg {
+  margin-top: var(--space-3xs);
+  font-size: var(--step--2);
+  line-height: 1.5;
+}
+
+.fv-ok {
+  color: var(--success, #2d6a4f);
+}
+
+.fv-error {
+  color: var(--danger, #c1121f);
+}
+
 /* ── TFE file upload queue (.tfe-file-queue) ────────────────────────────── */
 
 .admin-files-fieldgroup {
diff --git a/app/public/assets/js/file-upload-queue.js b/app/public/assets/js/file-upload-queue.js
index 044fb60..358c60e 100644
--- a/app/public/assets/js/file-upload-queue.js
+++ b/app/public/assets/js/file-upload-queue.js
@@ -11,139 +11,245 @@
  * after swap without a global event listener.
  */
 window.XamxamInitFileUploads = function () {
-  console.log('[file-upload-queue] XamxamInitFileUploads called');
-  var ICON = {
-    pdf: '\uD83D\uDCC4', video: '\uD83C\uDFAC', audio: '\uD83D\uDD0A',
-    zip: '\uD83D\uDDDC\uFE0F', vtt: '\uD83D\uDCAC', image: '\uD83D\uDDBC\uFE0F', other: '\uD83D\uDCCE'
-  };
+	console.log("[file-upload-queue] XamxamInitFileUploads called");
+	var ICON = {
+		pdf: "\uD83D\uDCC4",
+		video: "\uD83C\uDFAC",
+		audio: "\uD83D\uDD0A",
+		zip: "\uD83D\uDDDC\uFE0F",
+		vtt: "\uD83D\uDCAC",
+		image: "\uD83D\uDDBC\uFE0F",
+		other: "\uD83D\uDCCE",
+	};
 
-  function iconFor(file) {
-    var t = file.type || '', n = file.name.toLowerCase();
-    if (/^image\//.test(t)) return ICON.image;
-    if (t === 'application/pdf' || /\.pdf$/.test(n)) return ICON.pdf;
-    if (/^video\//.test(t) || /\.(mp4|webm|mov|ogv)$/.test(n)) return ICON.video;
-    if (/^audio\//.test(t) || /\.(mp3|ogg|oga|wav|flac|aac|m4a)$/.test(n)) return ICON.audio;
-    if (/\.(zip|tar|gz|tgz)$/.test(n)) return ICON.zip;
-    if (/\.vtt$/.test(n)) return ICON.vtt;
-    return ICON.other;
-  }
+	function iconFor(file) {
+		var t = file.type || "",
+			n = file.name.toLowerCase();
+		if (/^image\//.test(t)) return ICON.image;
+		if (t === "application/pdf" || /\.pdf$/.test(n)) return ICON.pdf;
+		if (/^video\//.test(t) || /\.(mp4|webm|mov|ogv)$/.test(n))
+			return ICON.video;
+		if (/^audio\//.test(t) || /\.(mp3|ogg|oga|wav|flac|aac|m4a)$/.test(n))
+			return ICON.audio;
+		if (/\.(zip|tar|gz|tgz)$/.test(n)) return ICON.zip;
+		if (/\.vtt$/.test(n)) return ICON.vtt;
+		return ICON.other;
+	}
 
-  function humanSize(b) {
-    return b >= 1073741824 ? (b / 1073741824).toFixed(2) + ' GB'
-         : b >= 1048576   ? (b / 1048576).toFixed(2) + ' MB'
-         : b >= 1024      ? (b / 1024).toFixed(1) + ' KB'
-         : b + ' B';
-  }
+	function humanSize(b) {
+		return b >= 1073741824
+			? (b / 1073741824).toFixed(2) + " GB"
+			: b >= 1048576
+				? (b / 1048576).toFixed(2) + " MB"
+				: b >= 1024
+					? (b / 1024).toFixed(1) + " KB"
+					: b + " B";
+	}
 
-  function esc(s) { return s.replace(/[&<>"]/g, function(c){ return {'&':'&amp;','<':'&lt;','>':'&gt;','"':'&quot;'}[c]; }); }
+	function esc(s) {
+		return s.replace(/[&<>"]/g, function (c) {
+			return { "&": "&amp;", "<": "&lt;", ">": "&gt;", '"': "&quot;" }[c];
+		});
+	}
 
-  // ── 1. TFE multi-file queue ────────────────────────────────────────────
-  var picker   = document.getElementById('tfe-files-input');
-  var queue    = document.getElementById('tfe-file-queue');
-  var empty    = document.getElementById('tfe-file-queue-empty');
-  var sortHint = document.getElementById('tfe-file-queue-sort-hint');
-  if (picker && queue) {
-    console.log('[file-upload-queue] init TFE queue picker=', picker, 'multiple=', picker.multiple);
-    var fileArray = [];
+	// ── 1. TFE multi-file queue ────────────────────────────────────────────
+	var picker = document.getElementById("tfe-files-input");
+	var queue = document.getElementById("tfe-file-queue");
+	var empty = document.getElementById("tfe-file-queue-empty");
+	var sortHint = document.getElementById("tfe-file-queue-sort-hint");
+	if (picker && queue) {
+		console.log(
+			"[file-upload-queue] init TFE queue picker=",
+			picker,
+			"multiple=",
+			picker.multiple,
+		);
+		var fileArray = [];
 
-    if (typeof Sortable !== 'undefined') {
-      Sortable.create(queue, { animation: 150, handle: '.fq-drag-handle', ghostClass: 'fq-ghost',
-        onEnd: function () {
-          var items = queue.querySelectorAll('.fq-item');
-          var newArr = Array.prototype.map.call(items, function (li) { return fileArray[parseInt(li.getAttribute('data-idx'), 10)]; });
-          fileArray = newArr;
-          renderQueue();
-        }
-      });
-    }
+		if (typeof Sortable !== "undefined") {
+			Sortable.create(queue, {
+				animation: 150,
+				handle: ".fq-drag-handle",
+				ghostClass: "fq-ghost",
+				onEnd: function () {
+					var items = queue.querySelectorAll(".fq-item");
+					var newArr = Array.prototype.map.call(items, function (li) {
+						return fileArray[parseInt(li.getAttribute("data-idx"), 10)];
+					});
+					fileArray = newArr;
+					renderQueue();
+				},
+			});
+		}
 
-    picker.onchange = function () {
-      console.log('[file-upload-queue] onchange fired, files count:', picker.files.length, 'names:', Array.from(picker.files).map(function(f){return f.name}));
-      fileArray = fileArray.concat(Array.from(picker.files));
-      console.log('[file-upload-queue] fileArray after concat, length:', fileArray.length);
-      picker.value = '';
-      renderQueue();
-    };
+		picker.onchange = function () {
+			console.log(
+				"[file-upload-queue] onchange fired, files count:",
+				picker.files.length,
+				"names:",
+				Array.from(picker.files).map(function (f) {
+					return f.name;
+				}),
+			);
+			fileArray = fileArray.concat(Array.from(picker.files));
+			console.log(
+				"[file-upload-queue] fileArray after concat, length:",
+				fileArray.length,
+			);
+			picker.value = "";
+			renderQueue();
+		};
 
-    function renderQueue() {
-      queue.innerHTML = '';
-      if (!fileArray.length) { empty.style.display = ''; if (sortHint) sortHint.style.display = 'none'; injectHiddenFields([]); return; }
-      empty.style.display = 'none';
-      if (sortHint) sortHint.style.display = '';
-      fileArray.forEach(function (file, idx) {
-        var li = document.createElement('li');
-        li.className = 'fq-item';
-        li.setAttribute('data-idx', idx);
-        li.innerHTML =
-          '<span class="fq-drag-handle" title="R\u00e9ordonner">\u2820</span>' +
-          '<span class="fq-icon">' + iconFor(file) + '</span>' +
-          '<span class="fq-info"><span class="fq-name">' + esc(file.name) + '</span>' +
-          '<span class="fq-size">' + humanSize(file.size) + '</span></span>' +
-          '<button type="button" class="admin-btn-remove fq-remove" aria-label="Retirer ' + esc(file.name) + '">&#x2715;</button>';
-        li.querySelector('.fq-remove').onclick = (function (i) { return function () { fileArray.splice(i, 1); renderQueue(); }; })(idx);
-        queue.appendChild(li);
-      });
-      injectHiddenFields(Array.from(queue.querySelectorAll('.fq-item')));
-    }
+		function renderQueue() {
+			queue.innerHTML = "";
+			if (!fileArray.length) {
+				empty.style.display = "";
+				if (sortHint) sortHint.style.display = "none";
+				injectHiddenFields([]);
+				return;
+			}
+			empty.style.display = "none";
+			if (sortHint) sortHint.style.display = "";
+			fileArray.forEach(function (file, idx) {
+				var li = document.createElement("li");
+				li.className = "fq-item";
+				li.setAttribute("data-idx", idx);
+				li.innerHTML =
+					'<span class="fq-drag-handle" title="R\u00e9ordonner">\u2820</span>' +
+					'<span class="fq-icon">' +
+					iconFor(file) +
+					"</span>" +
+					'<span class="fq-info"><span class="fq-name">' +
+					esc(file.name) +
+					"</span>" +
+					'<span class="fq-size">' +
+					humanSize(file.size) +
+					"</span></span>" +
+					'<button type="button" class="admin-btn-remove fq-remove" aria-label="Retirer ' +
+					esc(file.name) +
+					'">&#x2715;</button>';
+				li.querySelector(".fq-remove").onclick = (function (i) {
+					return function () {
+						fileArray.splice(i, 1);
+						renderQueue();
+					};
+				})(idx);
+				queue.appendChild(li);
+			});
+			injectHiddenFields(Array.from(queue.querySelectorAll(".fq-item")));
+		}
 
-    function injectHiddenFields(items) {
-      var form = picker.closest('form');
-      if (!form) return;
-      form.querySelectorAll('.fq-hidden-label, .fq-hidden-order').forEach(function (el) { el.remove(); });
-      items.forEach(function (li, sortedIdx) {
-        var label = li.querySelector('.fq-label');
-        var lInp = document.createElement('input'); lInp.type = 'hidden'; lInp.name = 'file_labels[]'; lInp.value = label ? label.value : ''; lInp.className = 'fq-hidden-label'; form.appendChild(lInp);
-        var oInp = document.createElement('input'); oInp.type = 'hidden'; oInp.name = 'file_orders[]'; oInp.value = sortedIdx + 1; oInp.className = 'fq-hidden-order'; form.appendChild(oInp);
-      });
-    }
+		function injectHiddenFields(items) {
+			var form = picker.closest("form");
+			if (!form) return;
+			form
+				.querySelectorAll(".fq-hidden-label, .fq-hidden-order")
+				.forEach(function (el) {
+					el.remove();
+				});
+			items.forEach(function (li, sortedIdx) {
+				var label = li.querySelector(".fq-label");
+				var lInp = document.createElement("input");
+				lInp.type = "hidden";
+				lInp.name = "file_labels[]";
+				lInp.value = label ? label.value : "";
+				lInp.className = "fq-hidden-label";
+				form.appendChild(lInp);
+				var oInp = document.createElement("input");
+				oInp.type = "hidden";
+				oInp.name = "file_orders[]";
+				oInp.value = sortedIdx + 1;
+				oInp.className = "fq-hidden-order";
+				form.appendChild(oInp);
+			});
+		}
 
-    // On submit, refresh hidden fields from current queue state
-    var form = picker.closest('form');
-    if (form) form.addEventListener('submit', function () { injectHiddenFields(Array.from(queue.querySelectorAll('.fq-item'))); });
-  }
+		// On submit, refresh hidden fields from current queue state
+		var form = picker.closest("form");
+		if (form)
+			form.addEventListener("submit", function () {
+				injectHiddenFields(Array.from(queue.querySelectorAll(".fq-item")));
+			});
+	}
 
-  // ── 2. Single-file previews (data-preview attribute) ────────────────────
-  document.querySelectorAll('input[type="file"][data-preview]').forEach(function (input) {
-    if (input.id === 'tfe-files-input') return;
-    console.log('[file-upload-queue] binding preview for', input.id, 'multiple=', input.multiple);
-    var container = document.getElementById(input.getAttribute('data-preview'));
-    if (!container) return;
-    input.onchange = function () {
-      container.innerHTML = '';
-      Array.from(input.files).forEach(function (file) {
-        var item = document.createElement('div'); item.className = 'fp-item';
-        if (/^image\//.test(file.type)) {
-          var img = document.createElement('img'); img.className = 'fp-thumb'; img.alt = file.name;
-          var reader = new FileReader();
-          reader.onload = function (e) { img.src = e.target.result; };
-          reader.readAsDataURL(file);
-          item.appendChild(img);
-        } else {
-          var ic = document.createElement('span'); ic.className = 'fp-icon'; ic.textContent = iconFor(file);
-          item.appendChild(ic);
-        }
-        var meta = document.createElement('span'); meta.className = 'fp-meta';
-        meta.innerHTML = '<span class="fp-name">' + esc(file.name) + '</span><span class="fp-size">' + humanSize(file.size) + '</span>';
-        item.appendChild(meta);
-        container.appendChild(item);
-      });
-    };
-  });
+	// ── 2. Single-file previews (data-preview attribute) ────────────────────
+	document
+		.querySelectorAll('input[type="file"][data-preview]')
+		.forEach(function (input) {
+			if (input.id === "tfe-files-input") return;
+			console.log(
+				"[file-upload-queue] binding preview for",
+				input.id,
+				"multiple=",
+				input.multiple,
+			);
+			var container = document.getElementById(
+				input.getAttribute("data-preview"),
+			);
+			if (!container) return;
+			input.onchange = function () {
+				container.innerHTML = "";
+				Array.from(input.files).forEach(function (file) {
+					var item = document.createElement("div");
+					item.className = "fp-item";
+					if (/^image\//.test(file.type)) {
+						var img = document.createElement("img");
+						img.className = "fp-thumb";
+						img.alt = file.name;
+						var reader = new FileReader();
+						reader.onload = function (e) {
+							img.src = e.target.result;
+						};
+						reader.readAsDataURL(file);
+						item.appendChild(img);
+					} else {
+						var ic = document.createElement("span");
+						ic.className = "fp-icon";
+						ic.textContent = iconFor(file);
+						item.appendChild(ic);
+					}
+					var meta = document.createElement("span");
+					meta.className = "fp-meta";
+					meta.innerHTML =
+						'<span class="fp-name">' +
+						esc(file.name) +
+						'</span><span class="fp-size">' +
+						humanSize(file.size) +
+						"</span>";
+					item.appendChild(meta);
+					container.appendChild(item);
+				});
+			};
+		});
 
-  // ── 3. Existing-files sortable (edit mode) ──────────────────────────────
-  var sortList = document.getElementById('existing-files-sortable');
-  if (sortList && typeof Sortable !== 'undefined') {
-    Sortable.create(sortList, { animation: 150, handle: '.admin-file-drag-handle', ghostClass: 'fq-ghost',
-      onEnd: function () {
-        sortList.querySelectorAll('input[name="file_sort_order[]"]').forEach(function (el) { el.remove(); });
-        sortList.querySelectorAll('.admin-file-list-item[data-file-id]').forEach(function (li) {
-          var inp = document.createElement('input'); inp.type = 'hidden'; inp.name = 'file_sort_order[]'; inp.value = li.getAttribute('data-file-id'); li.prepend(inp);
-        });
-      }
-    });
-  }
+	// ── 3. Existing-files sortable (edit mode) ──────────────────────────────
+	var sortList = document.getElementById("existing-files-sortable");
+	if (sortList && typeof Sortable !== "undefined") {
+		Sortable.create(sortList, {
+			animation: 150,
+			handle: ".admin-file-drag-handle",
+			ghostClass: "fq-ghost",
+			onEnd: function () {
+				sortList
+					.querySelectorAll('input[name="file_sort_order[]"]')
+					.forEach(function (el) {
+						el.remove();
+					});
+				sortList
+					.querySelectorAll(".admin-file-list-item[data-file-id]")
+					.forEach(function (li) {
+						var inp = document.createElement("input");
+						inp.type = "hidden";
+						inp.name = "file_sort_order[]";
+						inp.value = li.getAttribute("data-file-id");
+						li.prepend(inp);
+					});
+			},
+		});
+	}
 };
 
 // Bootstrap on page load
-if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', window.XamxamInitFileUploads);
+if (document.readyState === "loading")
+	document.addEventListener("DOMContentLoaded", window.XamxamInitFileUploads);
 else window.XamxamInitFileUploads();
diff --git a/app/public/partage/fichiers-fragment.php b/app/public/partage/fichiers-fragment.php
index 14ff15e..90b3f5d 100644
--- a/app/public/partage/fichiers-fragment.php
+++ b/app/public/partage/fichiers-fragment.php
@@ -197,7 +197,7 @@ $hasAnnexesChecked = !empty($_POST['has_annexes']);
         $label    = 'Annexes :';
         $accept   = '.pdf,.zip,.tar,.gz';
         $hint     = 'PDF ou archives ZIP/TAR. Max 500 MB.';
-        $required = false;
+        $required = !$adminMode;
         $multiple = true;
         include APP_ROOT . '/templates/partials/form/file-field.php';
         ?>
diff --git a/app/public/partage/index.php b/app/public/partage/index.php
index 705395e..e6c5f2d 100644
--- a/app/public/partage/index.php
+++ b/app/public/partage/index.php
@@ -36,6 +36,13 @@ if ($slug === 'format-website-fragment' && $_SERVER['REQUEST_METHOD'] === 'POST'
     exit;
 }
 
+// Special route: /partage/validate-file-fragment (HTMX fragment — file MIME/size validation)
+if ($slug === 'validate-file-fragment' && $_SERVER['REQUEST_METHOD'] === 'POST') {
+    App::boot();
+    require_once __DIR__ . '/../../src/Controllers/validate-file-fragment-shared.php';
+    exit;
+}
+
 // Special route: /partage/fichiers-fragment (HTMX fragment — format-aware fichiers block)
 if ($slug === 'fichiers-fragment' && $_SERVER['REQUEST_METHOD'] === 'POST') {
     App::boot();
diff --git a/app/src/Controllers/ThesisCreateController.php b/app/src/Controllers/ThesisCreateController.php
index b158940..ff4d3b4 100644
--- a/app/src/Controllers/ThesisCreateController.php
+++ b/app/src/Controllers/ThesisCreateController.php
@@ -512,6 +512,12 @@ class ThesisCreateController
         $exemplaireErg  = !empty($post['exemplaire_erg']);
         $cc2r = !empty($post['cc2r']);
 
+        // Annexes validation: if has_annexes is checked, at least one annexe file must be provided
+        $hasAnnexes = !empty($post['has_annexes']);
+        if (!$adminMode && $hasAnnexes && empty($_FILES['annexes']['name'][0])) {
+            throw new Exception('Veuillez fournir au moins un fichier d\'annexe.');
+        }
+
         return compact(
             'authorNames',
             'mail',
diff --git a/app/src/Controllers/validate-file-fragment-shared.php b/app/src/Controllers/validate-file-fragment-shared.php
new file mode 100644
index 0000000..2469d70
--- /dev/null
+++ b/app/src/Controllers/validate-file-fragment-shared.php
@@ -0,0 +1,191 @@
+<?php
+/**
+ * validate-file-fragment.php
+ *
+ * HTMX fragment: validates a single uploaded file against MIME type and size
+ * constraints. Returns an inline error message or clears the file input wrapper.
+ *
+ * Expected POST (multipart/form-data):
+ *   file         — the uploaded file
+ *   field_name   — 'couverture' | 'note_intention' | 'tfe' | 'annexes'
+ *   admin_mode   — '1' to skip validation (admins can upload anything)
+ */
+
+require_once __DIR__ . '/../../bootstrap.php';
+
+$adminMode = ($_POST['admin_mode'] ?? '0') === '1';
+$fieldName = $_POST['field_name'] ?? '';
+
+// Read file from the field-name-specific key (e.g., $_FILES['couverture'], $_FILES['annexes'])
+// For multi-file inputs (name ends with []), the first file is validated.
+$rawFile = $_FILES[$fieldName] ?? null;
+if ($rawFile && is_array($rawFile['name'] ?? null)) {
+    // Multi-file: flatten first entry
+    $file = [
+        'name'     => $rawFile['name'][0] ?? null,
+        'tmp_name' => $rawFile['tmp_name'][0] ?? null,
+        'error'    => $rawFile['error'][0] ?? UPLOAD_ERR_NO_FILE,
+        'size'     => $rawFile['size'][0] ?? 0,
+    ];
+    // Validate ALL selected files (batch validation)
+    $allFiles = [];
+    $count = count($rawFile['name'] ?? []);
+    for ($i = 0; $i < $count; $i++) {
+        $allFiles[] = [
+            'name'     => $rawFile['name'][$i] ?? null,
+            'tmp_name' => $rawFile['tmp_name'][$i] ?? null,
+            'error'    => $rawFile['error'][$i] ?? UPLOAD_ERR_NO_FILE,
+            'size'     => $rawFile['size'][$i] ?? 0,
+        ];
+    }
+} else {
+    $file = $rawFile;
+    $allFiles = $file ? [$file] : [];
+}
+
+// ── No file provided — clear any existing validation state ──────────────────
+if (empty($allFiles)) {
+    echo '';
+    exit;
+}
+
+if ($adminMode) {
+    // Admins: no validation, always OK
+    $count = count($allFiles);
+    echo '<span class="fv-ok">✓ ' . $count . ' fichier' . ($count > 1 ? 's' : '') . ' accepté' . ($count > 1 ? 's' : '') . '</span>';
+    exit;
+}
+
+// ── MIME + extension whitelist per field type ────────────────────────────────
+$finfo = new finfo(FILEINFO_MIME_TYPE);
+
+$constraints = match ($fieldName) {
+    'couverture' => [
+        'mimes'       => ['image/jpeg', 'image/png', 'image/webp'],
+        'exts'        => ['jpg', 'jpeg', 'png', 'webp'],
+        'maxSize'     => 20 * 1024 * 1024,  // 20 MB
+        'label'       => 'Image de couverture',
+        'allowedDesc' => 'JPG, PNG ou WEBP',
+        'maxSizeDesc' => '20 MB',
+    ],
+    'note_intention' => [
+        'mimes'       => ['application/pdf'],
+        'exts'        => ['pdf'],
+        'maxSize'     => 100 * 1024 * 1024, // 100 MB
+        'label'       => 'Note d\'intention',
+        'allowedDesc' => 'PDF uniquement',
+        'maxSizeDesc' => '100 MB',
+    ],
+    'tfe' => [
+        'mimes'       => [
+            'application/pdf',
+            'image/jpeg', 'image/png', 'image/gif', 'image/webp',
+            'video/mp4', 'video/webm', 'video/ogg', 'video/quicktime',
+            'audio/mpeg', 'audio/mp3', 'audio/ogg', 'audio/wav',
+            'audio/flac', 'audio/aac', 'audio/x-m4a', 'audio/mp4',
+            'text/vtt',
+            'application/zip', 'application/x-zip-compressed',
+            'application/x-tar', 'application/gzip',
+            'application/octet-stream',
+        ],
+        'exts'        => [
+            'jpg', 'jpeg', 'png', 'gif', 'webp', 'pdf',
+            'mp4', 'webm', 'ogv', 'mov',
+            'mp3', 'ogg', 'oga', 'wav', 'flac', 'aac', 'm4a',
+            'vtt', 'zip', 'tar', 'gz', 'tgz',
+        ],
+        'maxSize'     => 500 * 1024 * 1024, // 500 MB
+        'label'       => 'Fichier TFE',
+        'allowedDesc' => 'PDF, images, vidéos, audio, archives',
+        'maxSizeDesc' => '500 MB',
+    ],
+    'annexes' => [
+        'mimes'       => [
+            'application/pdf', 'image/jpeg', 'image/png', 'image/gif', 'image/webp',
+            'video/mp4', 'video/webm', 'video/ogg', 'video/quicktime',
+            'audio/mpeg', 'audio/mp3', 'audio/ogg', 'audio/wav',
+            'audio/flac', 'audio/aac', 'audio/x-m4a', 'audio/mp4',
+            'text/vtt',
+            'application/zip', 'application/x-zip-compressed',
+            'application/x-tar', 'application/gzip',
+            'application/octet-stream',
+        ],
+        'exts'        => [
+            'jpg', 'jpeg', 'png', 'gif', 'webp', 'pdf',
+            'mp4', 'webm', 'ogv', 'mov',
+            'mp3', 'ogg', 'oga', 'wav', 'flac', 'aac', 'm4a',
+            'vtt', 'zip', 'tar', 'gz', 'tgz',
+        ],
+        'maxSize'     => 500 * 1024 * 1024, // 500 MB
+        'label'       => 'Annexe',
+        'allowedDesc' => 'PDF, archives, images',
+        'maxSizeDesc' => '500 MB',
+    ],
+    default => [
+        'mimes'       => [],
+        'exts'        => [],
+        'maxSize'     => 500 * 1024 * 1024,
+        'label'       => 'Fichier',
+        'allowedDesc' => 'tous types',
+        'maxSizeDesc' => '500 MB',
+    ],
+};
+
+// ── Validate each file ──────────────────────────────────────────────────────
+$errors = [];
+$oks = [];
+foreach ($allFiles as $idx => $f) {
+    if (($f['error'] ?? UPLOAD_ERR_NO_FILE) !== UPLOAD_ERR_OK) {
+        continue;
+    }
+
+    $mimeType = $finfo->file($f['tmp_name']);
+    $ext      = strtolower(pathinfo($f['name'], PATHINFO_EXTENSION));
+    $size     = $f['size'];
+
+    if ($mimeType === 'text/plain' && $ext === 'vtt') {
+        $mimeType = 'text/vtt';
+    }
+
+    // PDF size limit
+    $effMaxSize = $constraints['maxSize'];
+    $effMaxDesc = $constraints['maxSizeDesc'];
+    if ($mimeType === 'application/pdf' || $ext === 'pdf') {
+        $effMaxSize = min($effMaxSize, 100 * 1024 * 1024);
+        $effMaxDesc = '100 MB';
+    }
+
+    // Validate MIME
+    $mimeOk = false;
+    if ($mimeType === 'application/octet-stream' && !in_array($ext, $constraints['exts'], true)) {
+        $mimeOk = false;
+    } elseif (in_array($mimeType, $constraints['mimes'], true)) {
+        $mimeOk = true;
+    } elseif (in_array($ext, $constraints['exts'], true)) {
+        $mimeOk = true;
+    }
+
+    if (!$mimeOk) {
+        $errors[] = '✕ <em>' . htmlspecialchars($f['name']) . '</em> : type non accepté.'
+                  . ' Formats acceptés : ' . htmlspecialchars($constraints['allowedDesc']) . '.';
+        continue;
+    }
+
+    if ($size > $effMaxSize) {
+        $mb = round($size / 1024 / 1024, 1);
+        $errors[] = '✕ <em>' . htmlspecialchars($f['name']) . '</em> : fichier trop volumineux ('
+                   . $mb . ' MB). Maximum : ' . htmlspecialchars($effMaxDesc) . '.';
+        continue;
+    }
+
+    $oks[] = '✓ <em>' . htmlspecialchars($f['name']) . '</em> : ' . round($size / 1024 / 1024, 1) . ' MB';
+}
+
+// ── Output ────────────────────────────────────────────────────────────────────
+if (!empty($errors)) {
+    echo '<span class="fv-error">' . implode('<br>', $errors) . '</span>';
+} elseif (!empty($oks)) {
+    echo '<span class="fv-ok">' . implode('<br>', $oks) . '</span>';
+} else {
+    echo '';
+}
diff --git a/app/templates/admin/acces.php b/app/templates/admin/acces.php
index c394e91..2d59799 100644
--- a/app/templates/admin/acces.php
+++ b/app/templates/admin/acces.php
@@ -207,6 +207,19 @@
 +%%%%%%% diff from: somsyvxz 249f7943 "Bulk bar anti-shift, tags icons, AP no-wrap, credits reorder" (rebased revision)
 +\\\\\\\        to: yztqkpzz 9c95f5ce "fix: TFE and annexes files not saved, plus keyword validation and file preview CSS" (rebased revision)
 ++                        $linkName = $link['name'] ?? '';
+++                        $linkExpiresVal = $link['expires_at'] ? date('Y-m-d\TH:i', strtotime($link['expires_at'])) : '';
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% diff from: yztqkpzz 9c95f5ce "fix: TFE and annexes files not saved, plus keyword validation and file preview CSS" (rebased revision)
+\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\        to: somsyvxz 249f7943 "Bulk bar anti-shift, tags icons, AP no-wrap, credits reorder" (rebased revision)
+-                        $linkName = $link['name'] ?? '';
+-                        $linkExpiresVal = $link['expires_at'] ? date('Y-m-d\TH:i', strtotime($link['expires_at'])) : '';
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% diff from: somsyvxz 14a3cd10 "Bulk bar anti-shift, tags icons, AP no-wrap, credits reorder" (rebase destination)
+\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\        to: uvnvvyny 8b83eae7 "fix: req annexes, add HTMX inline file validation (MIME/size)" (rebased revision)
+                         $linkName = $link['name'] ?? '';
+                         $linkExpiresVal = $link['expires_at'] ? date('Y-m-d\TH:i', strtotime($link['expires_at'])) : '';
+                         $linkLockedYear = $link['locked_year'] ?? null;
++%%%%%%% diff from: somsyvxz 249f7943 "Bulk bar anti-shift, tags icons, AP no-wrap, credits reorder" (rebased revision)
++\\\\\\\        to: uvnvvyny 09c854ea "fix: req annexes, add HTMX inline file validation (MIME/size)" (rebased revision)
+++                        $linkName = $link['name'] ?? '';
 ++                        $linkExpiresVal = $link['expires_at'] ? date('Y-m-d\TH:i', strtotime($link['expires_at'])) : '';
                     ?>
                     <tr class="admin-table-row" onclick="event.stopPropagation(); window.open('/partage/<?= urlencode($link['slug']) ?>', '_blank')" style="cursor:pointer">
diff --git a/app/templates/partials/form/file-field.php b/app/templates/partials/form/file-field.php
index b26fe1f..9703019 100644
--- a/app/templates/partials/form/file-field.php
+++ b/app/templates/partials/form/file-field.php
@@ -10,19 +10,35 @@
  *   bool        $required  — whether the field is required; default false
  *   bool        $multiple  — whether to allow multiple file selection; default false
  *   string|null $id        — override the id attribute (defaults to $name)
+ *   string|null $fieldName — validation field name for HTMX inline validation ('couverture', 'note_intention', 'tfe', 'annexes')
  */
 
-$accept   = $accept   ?? '';
-$hint     = $hint     ?? null;
-$hintRaw  = $hintRaw  ?? false; // when true, $hint is emitted as raw HTML
-$required = $required ?? false;
-$multiple = $multiple ?? false;
-$id       = $id       ?? $name;
+$accept    = $accept    ?? '';
+$hint      = $hint      ?? null;
+$hintRaw   = $hintRaw   ?? false; // when true, $hint is emitted as raw HTML
+$required  = $required  ?? false;
+$multiple  = $multiple  ?? false;
+$id        = $id        ?? $name;
+$fieldName = $fieldName ?? $name; // validation field name
 $previewId = 'fp-' . htmlspecialchars($id);
+
+// Determine HTMX POST endpoint for inline file validation
+if (defined('ADMIN_MODE') && ADMIN_MODE) {
+    $validateUrl = '/admin/validate-file-fragment.php';
+} else {
+    $validateUrl = '/partage/validate-file-fragment';
+}
 ?>
 <div>
     <label for="<?= htmlspecialchars($id) ?>"><?= htmlspecialchars($label) ?><?= $required ? ' <span class="asterisk">*</span>' : '' ?></label>
-    <div class="admin-file-input">
+    <div class="admin-file-input"
+         hx-post="<?= htmlspecialchars($validateUrl) ?>"
+         hx-encoding="multipart/form-data"
+         hx-trigger="change from:input[type='file']"
+         hx-target="find .file-validation-msg"
+         hx-swap="innerHTML"
+         hx-include="[name='admin_mode'], [name='edit_mode'], [name='field_name']">
+        <input type="hidden" name="field_name" value="<?= htmlspecialchars($fieldName) ?>">
         <input type="file"
                id="<?= htmlspecialchars($id) ?>"
                name="<?= htmlspecialchars($name) ?><?= $multiple ? '[]' : '' ?>"
@@ -30,6 +46,7 @@ $previewId = 'fp-' . htmlspecialchars($id);
                <?= $multiple ? 'multiple' : '' ?>
                <?= $required ? 'required' : '' ?>
                data-preview="<?= $previewId ?>">
+        <div class="file-validation-msg" aria-live="polite"></div>
         <div id="<?= $previewId ?>" class="file-preview-list" aria-live="polite"></div>
         <?php if ($hint): ?>
         <small><?= $hintRaw ? $hint : htmlspecialchars($hint) ?></small>
@@ -37,4 +54,4 @@ $previewId = 'fp-' . htmlspecialchars($id);
     </div>
 </div>
 <?php
-unset($accept, $hint, $hintRaw, $required, $multiple, $id, $previewId);
+unset($accept, $hint, $hintRaw, $required, $multiple, $id, $fieldName, $previewId, $validateUrl);