:root{
  --do-nen: #8b1c1c;
  --vang: #ffd54f;
  --vien: #d4af37;
  --xanh: #0d47a1;
}

body {
  font-family: "Segoe UI", Arial, sans-serif;
  background: radial-gradient(circle at top, #a42626, var(--do-nen));
  margin: 0;
  padding: 0;
  min-height: 100vh;
  color: var(--vang);
}

h2 {
  text-align: center;
  padding: 12px 10px;              /* ✅ GIẢM CHIỀU CAO */
  margin: 0;
  background: linear-gradient(135deg, #5c0f0f, #b71c1c);
  border-bottom: 3px solid var(--vien);   /* mỏng hơn */
  color: var(--vang);
  letter-spacing: 0.8px;           /* gọn chữ hơn */
  text-transform: uppercase;
  font-size: 22px;                 /* ✅ GIẢM CỠ CHỮ */
  font-weight: 800;
}


#hocSinhContainer {
  max-width: 1100px;
  margin: 30px auto;
  background: #fffaf0;
  border-radius: 22px;
  padding: 30px;
  box-shadow: 0 12px 35px rgba(0,0,0,0.35);
  border: 6px double var(--vien);
  color: var(--xanh);
  position: relative;
}

#hocSinhContainer::before,
#hocSinhContainer::after {
  content: "❖";
  position: absolute;
  font-size: 26px;
  color: var(--vien);
}
#hocSinhContainer::before { top: 10px; left: 15px; }
#hocSinhContainer::after  { top: 10px; right: 15px; }

.filter-bar {
  text-align: center;
  margin: 20px 0;
}

.filter-bar select,
.filter-bar button {
  padding: 8px 14px;
  margin: 0 6px;
  border-radius: 8px;
  border: 2px solid var(--vien);
  font-weight: bold;
}

.filter-bar button {
  background: linear-gradient(135deg, #7a1313, #b71c1c);
  color: var(--vang);
  cursor: pointer;
}

.table-section {
  margin-bottom: 40px;
  border-bottom: 3px dashed var(--vien);
  padding-bottom: 20px;
}

.table-section h3 {
  text-align: center;
  color: #b71c1c;
  font-size: 22px;
  margin-bottom: 10px;
}

.table-section img {
  border-radius: 10px;
  border: 3px solid var(--vien);
}

table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 15px;
  background: white;
}

th {
  background: linear-gradient(135deg, #7a1313, #b71c1c);
  color: var(--vang);
  padding: 10px;
  border: 1px solid var(--vien);
}

td {
  padding: 8px;
  border: 1px solid #ddd;
  text-align: center;
  color: var(--xanh);
}

.hs-thumb {
  width: 50px;
  height: 65px;
  object-fit: cover;
  border-radius: 6px;
  border: 1px solid #ccc;
}

.modal {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.6);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 9999;
}
.modal.show { display: flex; }

.student-card {
  background: #fffaf0;
  width: 360px;
  border-radius: 14px;
  padding: 20px;
  text-align: center;
  box-shadow: 0 0 20px rgba(0,0,0,0.4);
  border: 4px double var(--vien);
  color: var(--xanh);
}

.student-card img {
  width: 120px;
  height: 150px;
  object-fit: cover;
  border-radius: 8px;
  border: 2px solid var(--vien);
  margin-bottom: 10px;
}

.student-card h3 {
  color: #b71c1c;
  margin-bottom: 10px;
}

.student-card p {
  margin: 6px 0;
  font-size: 15px;
  text-align: left;
}

.close-btn {
  margin-top: 12px;
  padding: 8px 18px;
  border: none;
  border-radius: 8px;
  background: #b71c1c;
  color: var(--vang);
  cursor: pointer;
  font-weight: bold;
}

/* Ẩn bộ lọc + nút trình chiếu khi trang chạy trong ebook */
body.ebook-mode .filter-bar {
    display: none !important;
}

/* Ẩn luôn popup xem học sinh khi ở chế độ ebook để tránh “che màn” khi lật trang */
body.ebook-mode #studentModal {
    display: none !important;
}