/* ==========================================================================
   SHARED COMPONENTS (Theo Quy chuẩn thiết kế Lớp Mình 2026)
   ========================================================================== */

/* Thư viện Icon chuẩn (Feather Icons) */
.feather {
  width: 18px;
  height: 18px;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  fill: none;
  vertical-align: middle;
  display: inline-block;
  flex-shrink: 0;
}

.feather-sm {
  width: 14px;
  height: 14px;
}

.feather-lg {
  width: 22px;
  height: 22px;
}

.feather-xl {
  width: 32px;
  height: 32px;
}

/* 1. NÚT HÀNH ĐỘNG (Buttons) - Chiều cao 40px, Bo góc 8px */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  height: 40px;
  padding: 0 var(--space-4);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  border-radius: var(--radius-btn);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
  user-select: none;
  text-decoration: none;
}

.btn:hover {
  text-decoration: none;
}

.btn-primary {
  background-color: var(--color-primary);
  color: #FFFFFF;
}

.btn-primary:hover {
  background-color: var(--color-primary-hover);
  color: #FFFFFF;
  box-shadow: 0 2px 4px rgba(21, 101, 192, 0.25);
}

.btn-secondary {
  background-color: var(--color-surface);
  color: var(--color-text-main);
  border-color: var(--color-border);
}

.btn-secondary:hover {
  background-color: #F8FAFC;
  border-color: var(--color-border-hover);
}

.btn-danger {
  background-color: var(--color-danger);
  color: #FFFFFF;
}

.btn-danger:hover {
  background-color: #B91C1C;
  color: #FFFFFF;
  box-shadow: 0 2px 4px rgba(220, 38, 38, 0.25);
}

.btn-link {
  background: transparent;
  border: none;
  color: var(--color-primary);
  height: auto;
  padding: 4px 0;
  font-weight: var(--font-weight-medium);
}

.btn-link:hover {
  text-decoration: underline;
  color: var(--color-primary-hover);
}

.btn:disabled, .btn[disabled] {
  background-color: #F1F5F9;
  color: var(--color-text-muted);
  border-color: #E2E8F0;
  cursor: not-allowed;
  box-shadow: none;
}

/* Kích cỡ nút nhỏ hơn nếu cần */
.btn-sm {
  height: 32px;
  padding: 0 var(--space-3);
  font-size: var(--font-size-sm);
  border-radius: 6px;
}

/* 2. TRƯỜNG NHẬP LIỆU (Input fields) - Chiều cao 40px/44px, Bo góc 8px */
.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: var(--space-4);
  text-align: left;
}

.form-label {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-main);
}

.form-label .required {
  color: var(--color-danger);
}

.input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
  width: 100%;
}

.form-control {
  width: 100%;
  height: 44px;
  padding: 0 14px;
  font-size: var(--font-size-base);
  color: var(--color-text-main);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-input);
  outline: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-control::placeholder {
  color: #94A3B8;
}

.form-control:focus {
  border-color: var(--color-primary);
  border-width: 2px;
  padding: 0 13px; /* bù lại độ dày 2px */
  box-shadow: 0 0 0 3px rgba(21, 101, 192, 0.12);
}

.password-input-wrap {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  align-items: center;
  width: 100%;
}

.password-input-wrap .password-toggle-input {
  grid-column: 1;
  grid-row: 1;
  min-width: 0;
  width: 100%;
  padding-right: 44px;
}

.password-input-wrap .password-toggle-input:focus {
  padding-right: 43px;
}

.password-visibility-toggle {
  position: relative !important;
  grid-column: 1;
  grid-row: 1;
  justify-self: end;
  align-self: center;
  z-index: 1;
  display: inline-flex;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  padding: 0;
  margin-right: 2px;
  color: var(--color-text-secondary);
  background: transparent;
  border: 0;
  border-radius: var(--radius-input);
  cursor: pointer;
}

.password-visibility-toggle:hover {
  color: var(--color-primary);
}

.password-visibility-toggle:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: -3px;
}

.form-control:disabled, .form-control[readonly] {
  background-color: #F8FAFC;
  color: #94A3B8;
  cursor: not-allowed;
  border-color: #E2E8F0;
}

.input-icon-left .form-control {
  padding-left: 44px;
  padding-right: 14px;
}

.input-icon-right .form-control {
  padding-right: 44px;
  padding-left: 14px;
}

.input-icon {
  position: absolute;
  top: 0;
  bottom: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  color: var(--color-text-secondary);
  pointer-events: none;
}

.input-icon-left .input-icon {
  left: 4px;
  right: auto;
}

.input-icon-right .input-icon {
  right: 4px;
  left: auto;
}

.input-icon.right-clickable {
  pointer-events: auto;
  cursor: pointer;
}

.form-control.is-invalid {
  border-color: var(--color-danger);
}

.form-control.is-invalid:focus {
  box-shadow: 0 0 0 3px rgba(220, 38, 38, 0.15);
}

.form-error-msg {
  font-size: var(--font-size-xs);
  color: var(--color-danger);
  display: flex;
  align-items: center;
  gap: 4px;
}

.form-hint {
  font-size: var(--font-size-xs);
  color: var(--color-text-secondary);
}

/* Checkbox */
.form-checkbox {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  user-select: none;
  font-size: var(--font-size-sm);
  color: var(--color-text-main);
}

.form-checkbox input[type="checkbox"] {
  appearance: none;
  width: 18px;
  height: 18px;
  border: 1.5px solid var(--color-border-hover);
  border-radius: 4px;
  outline: none;
  cursor: pointer;
  display: inline-grid;
  place-content: center;
  transition: all var(--transition-fast);
  background-color: var(--color-surface);
}

.form-checkbox input[type="checkbox"]:checked {
  background-color: var(--color-primary);
  border-color: var(--color-primary);
}

.form-checkbox input[type="checkbox"]:checked::before {
  content: "";
  width: 10px;
  height: 6px;
  border-left: 2px solid white;
  border-bottom: 2px solid white;
  transform: rotate(-45deg) translate(1px, -1px);
}

/* 3. NHÃN TRẠNG THÁI (Status Badges) - Bo góc 6px, Cao 24px */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 3px 10px;
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-medium);
  border-radius: var(--radius-badge);
  white-space: nowrap;
}

.badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
}

.badge-success {
  background-color: var(--color-success-bg);
  color: var(--color-success);
}
.badge-success .badge-dot { background-color: var(--color-success); }

.badge-warning {
  background-color: var(--color-warning-bg);
  color: var(--color-warning);
}
.badge-warning .badge-dot { background-color: var(--color-warning); }

.badge-danger {
  background-color: var(--color-danger-bg);
  color: var(--color-danger);
}
.badge-danger .badge-dot { background-color: var(--color-danger); }

.badge-info {
  background-color: var(--color-info-bg);
  color: var(--color-info);
}
.badge-info .badge-dot { background-color: var(--color-info); }

.badge-neutral {
  background-color: var(--color-neutral-bg);
  color: var(--color-neutral);
}
.badge-neutral .badge-dot { background-color: var(--color-neutral); }

.badge-accent {
  background-color: var(--color-accent-bg);
  color: var(--color-accent);
}
.badge-accent .badge-dot { background-color: var(--color-accent); }

/* 4. THẺ VÀ KHỐI NỘI DUNG (Cards) - Bo góc 12px */
.card {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  padding: var(--space-6);
  box-shadow: var(--shadow-sm);
}

.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-4);
  padding-bottom: var(--space-3);
  border-bottom: 1px solid var(--color-border);
}

/* 5. THẺ ĐIỀU HƯỚNG TABS */
.nav-tabs {
  display: flex;
  gap: var(--space-6);
  border-bottom: 1px solid var(--color-border);
  margin-bottom: var(--space-6);
}

.tab-item {
  position: relative;
  padding: var(--space-3) 0;
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-secondary);
  background: none;
  border: none;
  cursor: pointer;
  transition: color var(--transition-fast);
}

.tab-item:hover {
  color: var(--color-primary);
}

.tab-item.active {
  color: var(--color-primary);
  font-weight: var(--font-weight-semibold);
}

.tab-item.active::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 100%;
  height: 2px;
  background-color: var(--color-primary);
}

/* 6. BẢNG DỮ LIỆU (Data Table) */
.table-container {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  overflow-x: auto;
  box-shadow: var(--shadow-sm);
}

.table-custom {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
}

.table-custom th {
  height: 44px;
  padding: 0 16px;
  background-color: #F8FAFC;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-secondary);
  border-bottom: 1px solid var(--color-border);
}

.table-custom td {
  min-height: 58px;
  height: 58px;
  padding: 12px 16px;
  font-size: var(--font-size-base);
  color: var(--color-text-main);
  border-bottom: 1px solid var(--color-border);
  vertical-align: middle;
}

.table-custom tr:last-child td {
  border-bottom: none;
}

.table-custom tr:hover td {
  background-color: #F9FBFE;
}

/* Phân trang (Pagination) */
.table-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 16px;
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  border-top: 1px solid var(--color-border);
  background-color: #FCFDFE;
}

.pagination {
  display: flex;
  align-items: center;
  gap: 4px;
}

.page-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 28px;
  height: 28px;
  padding: 0 6px;
  border-radius: 4px;
  border: 1px solid transparent;
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  background: transparent;
  cursor: pointer;
}

.page-btn:hover {
  background-color: #EDF2F7;
  color: var(--color-text-main);
}

.page-btn.active {
  background-color: var(--color-primary);
  color: #FFFFFF;
  font-weight: var(--font-weight-semibold);
}

/* 7. THÔNG BÁO NGẮN & CẢNH BÁO (Alert Banners) */
.alert {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-input);
  font-size: var(--font-size-sm);
  margin-bottom: var(--space-4);
}

.alert-success {
  background-color: var(--color-success-bg);
  border: 1px solid var(--color-success-border);
  color: var(--color-success);
}

.alert-info {
  background-color: var(--color-info-bg);
  border: 1px solid var(--color-info-border);
  color: var(--color-info);
}

.alert-warning {
  background-color: var(--color-warning-bg);
  border: 1px solid var(--color-warning-border);
  color: var(--color-warning);
}

.alert-danger {
  background-color: var(--color-danger-bg);
  border: 1px solid var(--color-danger-border);
  color: var(--color-danger);
}

/* 8. TRẠNG THÁI TRỐNG (Empty State) */
.empty-state {
  text-align: center;
  padding: var(--space-10) var(--space-6);
  background-color: var(--color-surface);
  border: 1px dashed var(--color-border);
  border-radius: var(--radius-card);
}

.empty-icon {
  width: 56px;
  height: 56px;
  margin: 0 auto var(--space-3);
  background-color: var(--color-primary-50);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-primary);
}

/* 9. KHUNG KHOÉT LỖ / PLACEHOLDER CHỨC NĂNG (Scaffold Slots) */
.feature-slot {
  background: #FFFFFF;
  border: 2px dashed #93C5FD;
  border-radius: var(--radius-card);
  padding: var(--space-6);
  position: relative;
  margin-top: var(--space-4);
  transition: all var(--transition-normal);
}

.feature-slot:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 12px rgba(21, 101, 192, 0.08);
}

.slot-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  border-radius: var(--radius-badge);
  background-color: #EFF6FF;
  color: var(--color-primary);
  margin-bottom: var(--space-2);
}

.slot-title {
  font-size: var(--font-size-md);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-main);
  margin-bottom: 6px;
}

.slot-desc {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  line-height: 1.5;
  margin-bottom: var(--space-4);
}

.slot-canvas {
  background: #F8FAFC;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-input);
  min-height: 160px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
  text-align: center;
  gap: var(--space-2);
}

.slot-canvas .code-hint {
  font-family: Consolas, monospace;
  font-size: 12px;
  color: #64748B;
  background: #EDF2F7;
  padding: 2px 8px;
  border-radius: 4px;
}

/* 10. MODAL / HỘP THOẠI XÁC NHẬN - Bo góc 16px */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.5);
  backdrop-filter: blur(2px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal-container {
  width: 90%;
  max-width: 480px;
  background: var(--color-surface);
  border-radius: var(--radius-modal);
  box-shadow: var(--shadow-modal);
  overflow: hidden;
  transform: translateY(16px);
  transition: transform var(--transition-normal);
}

.modal-overlay.active .modal-container {
  transform: translateY(0);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) var(--space-6);
  border-bottom: 1px solid var(--color-border);
}

.modal-title {
  font-size: var(--font-size-md);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-main);
}

.modal-close {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--color-text-secondary);
  font-size: 20px;
  padding: 4px;
}

.modal-body {
  padding: var(--space-6);
}

.modal-footer {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-6);
  background: #F8FAFC;
  border-top: 1px solid var(--color-border);
}

/* Các thông báo trạng thái UC-05/UC-06 cần ẩn thật dù .alert đặt display:flex. */
#studentMessage[hidden], #attendanceMessage[hidden], #historyMessage[hidden] { display: none; }