/* =============================================================================
   style.css — Smart Attendance System Admin Dashboard
   Responsive, professional styling with light theme.
   ============================================================================= */

/* ---- CSS Custom Properties (Design Tokens) -------------------------------- */
:root {
  --primary:        #2563eb;
  --primary-dark:   #1d4ed8;
  --primary-light:  #eff6ff;
  --success:        #16a34a;
  --success-light:  #f0fdf4;
  --warning:        #d97706;
  --warning-light:  #fffbeb;
  --danger:         #dc2626;
  --danger-light:   #fef2f2;
  --info:           #0891b2;
  --info-light:     #ecfeff;

  --text-primary:   #111827;
  --text-secondary: #6b7280;
  --text-muted:     #9ca3af;

  --bg-body:        #f3f4f6;
  --bg-card:        #ffffff;
  --bg-sidebar:     #1e293b;
  --sidebar-text:   #cbd5e1;
  --sidebar-active: #2563eb;

  --border:         #e5e7eb;
  --border-focus:   #2563eb;
  --radius:         8px;
  --radius-lg:      12px;
  --shadow:         0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md:      0 4px 6px rgba(0,0,0,0.07), 0 2px 4px rgba(0,0,0,0.06);
  --shadow-lg:      0 10px 15px rgba(0,0,0,0.1), 0 4px 6px rgba(0,0,0,0.05);

  --font-sans:      'Inter', system-ui, -apple-system, sans-serif;
  --sidebar-w:      240px;
  --header-h:       60px;
  --transition:     0.2s ease;
}

/* ---- Reset & Base ---------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { font-size: 16px; -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font-sans);
  background:  var(--bg-body);
  color:       var(--text-primary);
  line-height: 1.5;
  min-height:  100vh;
}

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

img { max-width: 100%; display: block; }
button { cursor: pointer; font-family: inherit; }
input, select, textarea { font-family: inherit; }

/* ---- Auth / Login Screen -------------------------------------------------- */
#auth-screen {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  background: linear-gradient(135deg, #1e293b 0%, #2563eb 100%);
  padding: 1rem;
}

.auth-card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  width: 100%;
  max-width: 400px;
  box-shadow: var(--shadow-lg);
}

.auth-logo {
  text-align: center;
  margin-bottom: 2rem;
}

.auth-logo h1 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-top: 0.75rem;
}

.auth-logo p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-top: 0.25rem;
}

.auth-logo .logo-icon {
  width: 56px;
  height: 56px;
  background: var(--primary-light);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto;
  font-size: 1.75rem;
}

/* ---- Layout: App Shell ---------------------------------------------------- */
#app-shell {
  display: flex;
  min-height: 100vh;
}

/* ---- Sidebar -------------------------------------------------------------- */
.sidebar {
  width: var(--sidebar-w);
  background: var(--bg-sidebar);
  color: var(--sidebar-text);
  position: fixed;
  top: 0; left: 0; bottom: 0;
  display: flex;
  flex-direction: column;
  z-index: 100;
  transition: transform var(--transition);
}

.sidebar-header {
  padding: 1.25rem 1rem;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.sidebar-header h2 {
  font-size: 0.95rem;
  font-weight: 700;
  color: #fff;
  line-height: 1.3;
}

.sidebar-header p {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 0.2rem;
}

.sidebar-nav {
  flex: 1;
  overflow-y: auto;
  padding: 0.75rem 0;
}

.nav-section-label {
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #64748b;
  padding: 0.75rem 1rem 0.25rem;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.6rem 1rem;
  color: var(--sidebar-text);
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: 0;
  transition: background var(--transition), color var(--transition);
  cursor: pointer;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
}

.nav-item:hover {
  background: rgba(255,255,255,0.07);
  color: #fff;
}

.nav-item.active {
  background: rgba(37,99,235,0.25);
  color: #93c5fd;
  border-left: 3px solid var(--sidebar-active);
}

.nav-item .nav-icon { font-size: 1.1rem; width: 20px; text-align: center; }

.sidebar-footer {
  padding: 1rem;
  border-top: 1px solid rgba(255,255,255,0.08);
}

.user-info {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-bottom: 0.75rem;
}

.user-avatar {
  width: 34px; height: 34px;
  background: var(--primary);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; color: #fff; font-size: 0.85rem;
  flex-shrink: 0;
}

.user-details { overflow: hidden; }
.user-name  { font-size: 0.8rem; font-weight: 600; color: #e2e8f0; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.user-email { font-size: 0.7rem; color: #64748b; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

/* ---- Main Content --------------------------------------------------------- */
.main-content {
  margin-left: var(--sidebar-w);
  flex: 1;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.topbar {
  height: var(--header-h);
  background: var(--bg-card);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  padding: 0 1.5rem;
  position: sticky;
  top: 0;
  z-index: 50;
  gap: 1rem;
}

.topbar-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
  flex: 1;
}

.topbar-actions { display: flex; gap: 0.5rem; align-items: center; }

/* Hamburger (mobile) */
.hamburger {
  display: none;
  background: none;
  border: none;
  font-size: 1.3rem;
  color: var(--text-primary);
  padding: 0.25rem;
}

.page-content { padding: 1.5rem; flex: 1; }

/* ---- Cards ---------------------------------------------------------------- */
.card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.card-header {
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.card-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
}

.card-body { padding: 1.25rem; }

/* ---- Stat Cards ----------------------------------------------------------- */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.stat-card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  display: flex;
  align-items: flex-start;
  gap: 1rem;
}

.stat-icon {
  width: 44px; height: 44px;
  border-radius: var(--radius);
  display: flex; align-items: center; justify-content: center;
  font-size: 1.3rem;
  flex-shrink: 0;
}

.stat-icon.blue   { background: var(--primary-light);  color: var(--primary); }
.stat-icon.green  { background: var(--success-light);  color: var(--success); }
.stat-icon.red    { background: var(--danger-light);   color: var(--danger); }
.stat-icon.amber  { background: var(--warning-light);  color: var(--warning); }
.stat-icon.cyan   { background: var(--info-light);     color: var(--info); }

.stat-value { font-size: 1.75rem; font-weight: 800; color: var(--text-primary); line-height: 1; }
.stat-label { font-size: 0.78rem; color: var(--text-secondary); margin-top: 0.25rem; }

/* ---- Forms ---------------------------------------------------------------- */
.form-group { margin-bottom: 1rem; }

.form-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.35rem;
}

.form-control {
  width: 100%;
  padding: 0.55rem 0.75rem;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.9rem;
  color: var(--text-primary);
  background: #fff;
  transition: border-color var(--transition), box-shadow var(--transition);
  outline: none;
}

.form-control:focus {
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px rgba(37,99,235,0.15);
}

.form-control::placeholder { color: var(--text-muted); }

select.form-control { cursor: pointer; }

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.form-hint { font-size: 0.78rem; color: var(--text-muted); margin-top: 0.25rem; }
.form-error { font-size: 0.78rem; color: var(--danger); margin-top: 0.25rem; }

/* ---- Buttons -------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.5rem 1rem;
  border-radius: var(--radius);
  font-size: 0.875rem;
  font-weight: 600;
  border: 1.5px solid transparent;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
  line-height: 1.4;
}

.btn-primary  { background: var(--primary);  color: #fff; border-color: var(--primary); }
.btn-primary:hover  { background: var(--primary-dark); border-color: var(--primary-dark); }

.btn-success  { background: var(--success);  color: #fff; border-color: var(--success); }
.btn-success:hover  { filter: brightness(0.92); }

.btn-danger   { background: var(--danger);   color: #fff; border-color: var(--danger); }
.btn-danger:hover   { filter: brightness(0.92); }

.btn-outline  { background: transparent; color: var(--primary); border-color: var(--primary); }
.btn-outline:hover  { background: var(--primary-light); }

.btn-secondary { background: var(--bg-body); color: var(--text-primary); border-color: var(--border); }
.btn-secondary:hover { background: var(--border); }

.btn-ghost { background: none; border-color: transparent; color: var(--text-secondary); padding: 0.4rem 0.6rem; }
.btn-ghost:hover { background: var(--bg-body); color: var(--text-primary); }

.btn-sm { padding: 0.3rem 0.7rem; font-size: 0.8rem; }
.btn-lg { padding: 0.75rem 1.5rem; font-size: 1rem; }
.btn-full { width: 100%; justify-content: center; }

.btn:disabled { opacity: 0.55; cursor: not-allowed; pointer-events: none; }

/* ---- Tables --------------------------------------------------------------- */
.table-wrapper { overflow-x: auto; }

table { width: 100%; border-collapse: collapse; font-size: 0.875rem; }

thead th {
  background: var(--bg-body);
  color: var(--text-secondary);
  font-weight: 600;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 0.65rem 0.875rem;
  text-align: left;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}

tbody tr { border-bottom: 1px solid var(--border); transition: background var(--transition); }
tbody tr:hover { background: #f9fafb; }
tbody tr:last-child { border-bottom: none; }

td { padding: 0.75rem 0.875rem; color: var(--text-primary); vertical-align: middle; }

.table-empty {
  text-align: center;
  padding: 3rem;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.table-empty .empty-icon { font-size: 2.5rem; margin-bottom: 0.5rem; }

/* ---- Badges --------------------------------------------------------------- */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.2rem 0.6rem;
  border-radius: 9999px;
  font-size: 0.72rem;
  font-weight: 600;
}

.badge-green  { background: var(--success-light); color: var(--success); }
.badge-red    { background: var(--danger-light);  color: var(--danger); }
.badge-amber  { background: var(--warning-light); color: var(--warning); }
.badge-blue   { background: var(--primary-light); color: var(--primary); }
.badge-gray   { background: #f3f4f6;              color: #6b7280; }

/* ---- Modal ---------------------------------------------------------------- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.45);
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  animation: fadeIn 0.15s ease;
}

@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }

.modal {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  width: 100%;
  max-width: 520px;
  max-height: 90vh;
  overflow-y: auto;
  animation: slideUp 0.2s ease;
}

@keyframes slideUp { from { transform: translateY(20px); opacity: 0; } to { transform: translateY(0); opacity: 1; } }

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border);
}

.modal-title { font-size: 1rem; font-weight: 700; }

.modal-body { padding: 1.5rem; }
.modal-footer {
  padding: 1rem 1.5rem;
  border-top: 1px solid var(--border);
  display: flex;
  gap: 0.75rem;
  justify-content: flex-end;
}

.btn-close {
  background: none;
  border: none;
  font-size: 1.3rem;
  color: var(--text-muted);
  cursor: pointer;
  line-height: 1;
  padding: 0.2rem;
  border-radius: 4px;
}
.btn-close:hover { background: var(--bg-body); color: var(--text-primary); }

/* ---- Toast Notifications -------------------------------------------------- */
#toast-container {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  z-index: 999;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  max-width: 360px;
}

.toast {
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  padding: 0.85rem 1rem;
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  border-left: 4px solid var(--primary);
  animation: toastIn 0.25s ease;
  font-size: 0.875rem;
}

@keyframes toastIn { from { transform: translateX(110%); } to { transform: translateX(0); } }

.toast.success { border-color: var(--success); }
.toast.error   { border-color: var(--danger); }
.toast.warning { border-color: var(--warning); }
.toast-icon    { font-size: 1.1rem; flex-shrink: 0; margin-top: 0.05rem; }
.toast-msg     { flex: 1; color: var(--text-primary); }
.toast-close   { background: none; border: none; color: var(--text-muted); cursor: pointer; font-size: 1rem; padding: 0; }

/* ---- Search & Filters ----------------------------------------------------- */
.filter-bar {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  align-items: center;
  margin-bottom: 1rem;
}

.search-box {
  position: relative;
  flex: 1;
  min-width: 200px;
}

.search-box input {
  padding-left: 2.25rem;
}

.search-icon {
  position: absolute;
  left: 0.7rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  font-size: 0.95rem;
  pointer-events: none;
}

/* ---- Pagination ----------------------------------------------------------- */
.pagination {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 0;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.pagination-info { font-size: 0.8rem; color: var(--text-secondary); }

.pagination-controls { display: flex; gap: 0.25rem; }

.page-btn {
  width: 32px; height: 32px;
  display: flex; align-items: center; justify-content: center;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-card);
  color: var(--text-primary);
  font-size: 0.8rem;
  cursor: pointer;
  transition: all var(--transition);
}
.page-btn:hover  { background: var(--primary-light); border-color: var(--primary); color: var(--primary); }
.page-btn.active { background: var(--primary); color: #fff; border-color: var(--primary); }
.page-btn:disabled { opacity: 0.4; cursor: not-allowed; }

/* ---- Calendar / Holidays Panel -------------------------------------------- */
.calendar-panel { display: none; }
.calendar-panel.open { display: block; }

/* ---- Demo Mode Banner ----------------------------------------------------- */
.demo-banner {
  background: linear-gradient(135deg, #7c3aed, #2563eb);
  color: #fff;
  border-radius: var(--radius-lg);
  padding: 1.25rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.demo-banner h3 { font-size: 1.05rem; font-weight: 700; }
.demo-banner p  { font-size: 0.85rem; opacity: 0.85; }

/* ---- Loading Spinner ------------------------------------------------------ */
.spinner {
  display: inline-block;
  width: 20px; height: 20px;
  border: 2.5px solid rgba(37,99,235,0.2);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

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

.loading-overlay {
  position: absolute;
  inset: 0;
  background: rgba(255,255,255,0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: inherit;
  z-index: 10;
}

/* ---- Utility Classes ------------------------------------------------------ */
.hidden   { display: none !important; }
.flex     { display: flex; }
.flex-1   { flex: 1; }
.gap-1    { gap: 0.25rem; }
.gap-2    { gap: 0.5rem; }
.gap-3    { gap: 0.75rem; }
.gap-4    { gap: 1rem; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.wrap     { flex-wrap: wrap; }
.grid-2   { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.mt-1     { margin-top: 0.25rem; }
.mt-2     { margin-top: 0.5rem; }
.mt-3     { margin-top: 0.75rem; }
.mt-4     { margin-top: 1rem; }
.mb-4     { margin-bottom: 1rem; }
.mb-6     { margin-bottom: 1.5rem; }
.text-sm  { font-size: 0.875rem; }
.text-xs  { font-size: 0.75rem; }
.text-muted { color: var(--text-secondary); }
.font-bold { font-weight: 700; }
.text-danger { color: var(--danger); }
.text-success { color: var(--success); }
.text-right { text-align: right; }
.w-full   { width: 100%; }
.relative { position: relative; }

/* ---- Responsive: Mobile --------------------------------------------------- */
@media (max-width: 768px) {
  .sidebar {
    transform: translateX(-100%);
  }
  .sidebar.open {
    transform: translateX(0);
  }
  .sidebar-overlay {
    display: block;
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.4);
    z-index: 99;
  }
  .main-content { margin-left: 0; }
  .hamburger { display: block; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .form-row { grid-template-columns: 1fr; }
  .filter-bar { flex-direction: column; align-items: stretch; }
  .search-box { min-width: unset; }
  .grid-2 { grid-template-columns: 1fr; }
  .modal { max-width: 100%; }
  .page-content { padding: 1rem; }
}

@media (max-width: 480px) {
  .stats-grid { grid-template-columns: 1fr; }
}