diff --git a/static/app.js b/static/app.js
index 458af88..47fed08 100644
--- a/static/app.js
+++ b/static/app.js
@@ -263,7 +263,7 @@
       var countEl = sCards[k].querySelector('.study-card-count');
       var name = nameEl ? nameEl.textContent.trim() : '';
       var count = parseInt(countEl ? countEl.textContent : '0') || 0;
-      studyItems.push({ name: name, count: count });
+      studyItems.push({ name: name, count: count, last_checkin_date: sCards[k].dataset.lastDate || '' });
     }
 
     return { morning: morningItems, evening: eveningItems, study: studyItems };
@@ -300,7 +300,7 @@
     for (var sp=0; sp<PRESET_STUDY_ITEMS.length; sp++) {
       var sName = PRESET_STUDY_ITEMS[sp];
       var saved = studyMap[sName] || { count: 0 };
-      renderStudyCard(sName, saved.count || 0);
+      renderStudyCard(sName, saved.count || 0, saved.last_checkin_date || '');
     }
   }
 
@@ -345,32 +345,42 @@
 
   /* ── 勤学打卡卡片 ── */
 
-  function renderStudyCard(name, count) {
+  function renderStudyCard(name, count, lastDate) {
     var container = document.getElementById('study-cards');
+    var today = fmtDate(new Date());
+    var checked = count > 0;
+    var checkedToday = lastDate === today;
+    var btnText = checkedToday ? '已打卡' : '打卡';
     var div = document.createElement('div');
-    div.className = 'study-card' + (count > 0 ? ' checked' : '');
+    div.className = 'study-card' + (checked ? ' checked' : '');
+    div.setAttribute('data-last-date', lastDate || '');
     div.innerHTML =
       '<div class="study-card-info">' +
         '<span class="study-card-name">' + esc(name) + '</span>' +
         '<span class="study-card-count">' + count + '</span>' +
       '</div>' +
-      '<button class="study-card-btn" onclick="checkinStudy(this)">打卡</button>';
+      '<button class="study-card-btn' + (checkedToday ? ' done' : '') + '" onclick="checkinStudy(this)">' + btnText + '</button>';
     container.appendChild(div);
   }
 
   window.checkinStudy = function(btn) {
     var card = btn.closest('.study-card');
+    var today = fmtDate(new Date());
+    if (card.dataset.lastDate === today) { showToast('今天已打卡', 'info'); return; }
     var countEl = card.querySelector('.study-card-count');
     var count = parseInt(countEl.textContent) + 1;
     countEl.textContent = count;
-    if (count > 0) card.classList.add('checked');
+    card.dataset.lastDate = today;
+    card.classList.add('checked');
+    btn.classList.add('done');
+    btn.textContent = '已打卡';
     triggerAutoSave();
   };
 
   function initStudyPresets() {
     document.getElementById('study-cards').innerHTML = '';
     for (var i=0; i<PRESET_STUDY_ITEMS.length; i++) {
-      renderStudyCard(PRESET_STUDY_ITEMS[i], 0);
+      renderStudyCard(PRESET_STUDY_ITEMS[i], 0, '');
     }
   }
 
diff --git a/static/style.css b/static/style.css
index 2e1f41c..d3d42e6 100644
--- a/static/style.css
+++ b/static/style.css
@@ -1793,3 +1793,4 @@ body {
 .study-card.checked .study-card-count { background:var(--success); color:#FFF; }
 .study-card-btn { padding:6px 14px; border:1px solid var(--primary); border-radius:var(--radius-sm); background:transparent; color:var(--primary); font-size:12px; font-weight:500; cursor:pointer; transition:all 0.15s; font-family:inherit; white-space:nowrap; }
 .study-card-btn:hover { background:var(--primary); color:#FFF; }
+.study-card-btn.done { background:var(--success-light); color:var(--success); border-color:var(--success); cursor:default; }