/* Google Fonts & Base Variables */
:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --primary-dark: #1e40af;
  
  --success: #16a34a;
  --success-light: #dcfce7;
  --success-dark: #15803d;
  
  --danger: #dc2626;
  --danger-light: #fee2e2;
  --danger-dark: #b91c1c;
  
  --warning: #d97706;
  --warning-light: #fef3c7;
  --warning-dark: #b45309;
  
  --purple: #7c3aed;
  --purple-light: #f3e8ff;
  --purple-dark: #6d28d9;
  
  --cyan: #0891b2;
  --cyan-light: #cffafe;
  --cyan-dark: #0e7490;
  
  --bg-main: #f8fafc;
  --bg-card: #ffffff;
  --text-main: #0f172a;
  --text-muted: #64748b;
  --text-sub: #475569;
  --border: #e2e8f0;
  --border-focus: #3b82f6;
  
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-full: 9999px;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

body {
  font-family: 'Prompt', 'Sarabun', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background-color: var(--bg-main);
  color: var(--text-main);
  line-height: 1.5;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Container */
.app-container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 16px 16px 100px 16px;
  width: 100%;
}

/* Header */
.app-header {
  background: linear-gradient(135deg, #1e3a8a 0%, #2563eb 50%, #3b82f6 100%);
  color: #ffffff;
  padding: 24px 20px 20px 20px;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  margin-bottom: 20px;
  position: relative;
  overflow: hidden;
}

.app-header::after {
  content: "";
  position: absolute;
  top: -50px;
  right: -50px;
  width: 180px;
  height: 180px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 50%;
  pointer-events: none;
}

.header-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}

.header-brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.header-icon {
  background: rgba(255, 255, 255, 0.2);
  width: 46px;
  height: 46px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  backdrop-filter: blur(4px);
}

.header-title h1 {
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.header-title p {
  font-size: 0.85rem;
  color: #e0e7ff;
}

.db-status-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.78rem;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  background: rgba(0, 0, 0, 0.25);
  backdrop-filter: blur(4px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  cursor: pointer;
  transition: all 0.2s;
}

.db-status-badge:hover {
  background: rgba(0, 0, 0, 0.4);
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #22c55e;
}
.status-dot.offline {
  background: #ef4444;
}

/* Nav Tabs */
.nav-tabs {
  display: flex;
  background: #e2e8f0;
  border-radius: var(--radius-md);
  padding: 4px;
  gap: 4px;
  margin-bottom: 20px;
}

.nav-tab-btn {
  flex: 1;
  padding: 10px 14px;
  border: none;
  background: transparent;
  color: var(--text-sub);
  font-size: 0.92rem;
  font-weight: 600;
  font-family: inherit;
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: all 0.2s ease;
}

.nav-tab-btn.active {
  background: #ffffff;
  color: var(--primary);
  box-shadow: var(--shadow-sm);
}

.nav-tab-btn:hover:not(.active) {
  background: rgba(255, 255, 255, 0.5);
  color: var(--text-main);
}

/* Cards & Sections */
.card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border);
  padding: 20px;
  margin-bottom: 20px;
}

.card-title-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
  flex-wrap: wrap;
  gap: 10px;
}

.card-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 8px;
}

/* Filter Bar */
.filter-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 12px;
  align-items: end;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-sub);
}

.form-control {
  font-family: inherit;
  font-size: 0.92rem;
  padding: 9px 12px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: #ffffff;
  color: var(--text-main);
  transition: border-color 0.2s, box-shadow 0.2s;
  outline: none;
}

.form-control:focus {
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

/* Date Navigator */
.date-navigator {
  display: flex;
  align-items: center;
  gap: 8px;
}

.btn-icon {
  background: #f1f5f9;
  border: 1px solid var(--border);
  color: var(--text-main);
  width: 38px;
  height: 38px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  transition: all 0.15s;
}

.btn-icon:hover {
  background: #e2e8f0;
}

/* Thai Date Tag */
.thai-date-badge {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--primary-dark);
  background: var(--primary-light);
  padding: 6px 12px;
  border-radius: var(--radius-full);
  display: inline-block;
  margin-top: 6px;
}

/* Status Summary Badges */
.summary-bar {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: 10px;
  margin-bottom: 20px;
}

.stat-box {
  border-radius: var(--radius-md);
  padding: 12px 14px;
  display: flex;
  flex-direction: column;
  border: 1px solid transparent;
  transition: transform 0.15s, box-shadow 0.15s;
}

.stat-box:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

.stat-box .stat-label {
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.stat-box .stat-val {
  font-size: 1.5rem;
  font-weight: 800;
  margin-top: 2px;
  line-height: 1.1;
}

.stat-box.stat-present { background: var(--success-light); color: var(--success-dark); border-color: #86efac; }
.stat-box.stat-absent { background: var(--danger-light); color: var(--danger-dark); border-color: #fca5a5; }
.stat-box.stat-leave { background: var(--warning-light); color: var(--warning-dark); border-color: #fde047; }
.stat-box.stat-late { background: var(--purple-light); color: var(--purple-dark); border-color: #d8b4fe; }
.stat-box.stat-activity { background: var(--cyan-light); color: var(--cyan-dark); border-color: #67e8f9; }
.stat-box.stat-total { background: #f1f5f9; color: var(--text-sub); border-color: var(--border); }

/* Quick Actions Bar */
.action-toolbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
  padding: 12px 16px;
  background: #f8fafc;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  margin-bottom: 16px;
}

.toolbar-buttons {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

/* Notice Banner */
.notice-banner {
  padding: 10px 14px;
  border-radius: var(--radius-md);
  font-size: 0.88rem;
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 16px;
}

.notice-banner.saved {
  background: #dcfce7;
  color: #166534;
  border: 1px solid #86efac;
}

.notice-banner.unsaved {
  background: #fef3c7;
  color: #92400e;
  border: 1px solid #fcd34d;
}

/* Student Attendance List */
.student-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.student-card {
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.student-card:hover {
  border-color: #cbd5e1;
  box-shadow: var(--shadow-sm);
}

.student-card.selected-present { border-left: 5px solid var(--success); }
.student-card.selected-absent { border-left: 5px solid var(--danger); }
.student-card.selected-leave { border-left: 5px solid var(--warning); }
.student-card.selected-late { border-left: 5px solid var(--purple); }
.student-card.selected-activity { border-left: 5px solid var(--cyan); }

.student-info-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}

.student-main-info {
  display: flex;
  align-items: center;
  gap: 10px;
}

.student-no-badge {
  background: #f1f5f9;
  color: var(--text-sub);
  font-weight: 700;
  font-size: 0.85rem;
  width: 32px;
  height: 32px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border);
}

.student-name-text {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-main);
}

.student-code-text {
  font-size: 0.78rem;
  color: var(--text-muted);
  background: #f8fafc;
  padding: 2px 6px;
  border-radius: 4px;
  border: 1px solid #f1f5f9;
}

/* Status Selector Buttons Group */
.status-btn-group {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  width: 100%;
}

.status-btn {
  flex: 1;
  min-width: 60px;
  padding: 8px 6px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: #f8fafc;
  color: var(--text-sub);
  font-size: 0.88rem;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  transition: all 0.15s ease;
  user-select: none;
}

.status-btn:active {
  transform: scale(0.97);
}

/* Status Button Active States */
.status-btn[data-status="มา"].active {
  background: var(--success);
  color: #ffffff;
  border-color: var(--success-dark);
  box-shadow: 0 2px 4px rgba(22, 163, 74, 0.3);
}

.status-btn[data-status="ขาด"].active {
  background: var(--danger);
  color: #ffffff;
  border-color: var(--danger-dark);
  box-shadow: 0 2px 4px rgba(220, 38, 38, 0.3);
}

.status-btn[data-status="ลา"].active {
  background: var(--warning);
  color: #ffffff;
  border-color: var(--warning-dark);
  box-shadow: 0 2px 4px rgba(217, 119, 6, 0.3);
}

.status-btn[data-status="มาสาย"].active {
  background: var(--purple);
  color: #ffffff;
  border-color: var(--purple-dark);
  box-shadow: 0 2px 4px rgba(124, 58, 237, 0.3);
}

.status-btn[data-status="กิจกรรม"].active {
  background: var(--cyan);
  color: #ffffff;
  border-color: var(--cyan-dark);
  box-shadow: 0 2px 4px rgba(8, 145, 178, 0.3);
}

/* Remark Toggle & Input */
.student-remark-row {
  display: flex;
  gap: 8px;
  align-items: center;
}

.remark-input {
  flex: 1;
  font-size: 0.82rem;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  border: 1px dashed var(--border);
  background: #fafafa;
  color: var(--text-main);
  outline: none;
  font-family: inherit;
}

.remark-input:focus {
  border: 1px solid var(--border-focus);
  background: #ffffff;
}

.quick-remark-tag {
  font-size: 0.72rem;
  background: #f1f5f9;
  border: 1px solid var(--border);
  color: var(--text-sub);
  padding: 2px 6px;
  border-radius: 4px;
  cursor: pointer;
}
.quick-remark-tag:hover {
  background: #e2e8f0;
}

/* Buttons */
.btn {
  font-family: inherit;
  font-size: 0.9rem;
  font-weight: 600;
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  transition: all 0.2s ease;
  user-select: none;
}

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

.btn-success {
  background: var(--success);
  color: #ffffff;
}
.btn-success:hover {
  background: var(--success-dark);
}

.btn-outline {
  background: #ffffff;
  border: 1px solid var(--border);
  color: var(--text-sub);
}
.btn-outline:hover {
  background: #f8fafc;
  color: var(--text-main);
  border-color: #cbd5e1;
}

.btn-danger {
  background: var(--danger-light);
  color: var(--danger-dark);
  border: 1px solid #fca5a5;
}
.btn-danger:hover {
  background: #fecaca;
}

.btn-lg {
  padding: 12px 24px;
  font-size: 1rem;
  border-radius: var(--radius-md);
}

/* Sticky Bottom Bar */
.sticky-bottom-bar {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-top: 1px solid var(--border);
  padding: 12px 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: 0 -4px 12px rgba(0, 0, 0, 0.06);
  z-index: 50;
  max-width: 1100px;
  margin: 0 auto;
}

.sticky-stats {
  display: flex;
  gap: 10px;
  font-size: 0.85rem;
  font-weight: 600;
}

/* History & Tables */
.table-responsive {
  overflow-x: auto;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  text-align: left;
}

.data-table th {
  background: #f8fafc;
  color: var(--text-sub);
  font-weight: 600;
  padding: 10px 12px;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}

.data-table td {
  padding: 10px 12px;
  border-bottom: 1px solid var(--border);
  color: var(--text-main);
}

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

.data-table tr:hover td {
  background: #f8fafc;
}

/* Status Pill in Table */
.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.76rem;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: var(--radius-full);
}

.status-pill.มา { background: var(--success-light); color: var(--success-dark); }
.status-pill.ขาด { background: var(--danger-light); color: var(--danger-dark); }
.status-pill.ลา { background: var(--warning-light); color: var(--warning-dark); }
.status-pill.มาสาย { background: var(--purple-light); color: var(--purple-dark); }
.status-pill.กิจกรรม { background: var(--cyan-light); color: var(--cyan-dark); }

/* Import Drop Zone */
.drop-zone {
  border: 2px dashed #94a3b8;
  border-radius: var(--radius-lg);
  padding: 30px 20px;
  text-align: center;
  background: #f8fafc;
  cursor: pointer;
  transition: all 0.2s;
}

.drop-zone:hover, .drop-zone.dragover {
  border-color: var(--primary);
  background: var(--primary-light);
}

.drop-icon {
  font-size: 40px;
  color: var(--primary);
  margin-bottom: 8px;
}

/* Modal */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(15, 23, 42, 0.6);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  z-index: 100;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s;
}

.modal-overlay.open {
  opacity: 1;
  pointer-events: auto;
}

.modal-box {
  background: #ffffff;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  max-width: 500px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  padding: 24px;
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.modal-title {
  font-size: 1.15rem;
  font-weight: 700;
}

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

/* Toast */
.toast-container {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 200;
  display: flex;
  flex-direction: column;
  gap: 8px;
  pointer-events: none;
}

.toast {
  background: #1e293b;
  color: #ffffff;
  padding: 12px 18px;
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  gap: 10px;
  pointer-events: auto;
  animation: slideIn 0.25s ease-out;
}

.toast.success { background: #15803d; }
.toast.error { background: #b91c1c; }
.toast.warning { background: #b45309; }

@keyframes slideIn {
  from { transform: translateX(100%); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}

/* Loading Spinner */
.spinner {
  display: inline-block;
  width: 16px;
  height: 16px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: #ffffff;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Responsive adjustments */
@media (max-width: 640px) {
  .app-container {
    padding: 12px 10px 90px 10px;
  }
  .app-header {
    padding: 18px 14px;
  }
  .header-title h1 {
    font-size: 1.15rem;
  }
  .summary-bar {
    grid-template-columns: repeat(3, 1fr);
    gap: 6px;
  }
  .stat-box {
    padding: 8px 10px;
  }
  .stat-box .stat-val {
    font-size: 1.2rem;
  }
  .status-btn {
    padding: 7px 4px;
    font-size: 0.82rem;
  }
}