:root {
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  
  /* Color System - Light & Crisp White Theme */
  --bg-main: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f8fafc;
  --border-color: #e2e8f0;
  --text-main: #0f172a;
  --text-muted: #64748b;
  
  /* Role Colors */
  --color-admin: #4f46e5; /* Indigo */
  --color-admin-glow: rgba(79, 70, 229, 0.15);
  --color-provider: #059669; /* Emerald */
  --color-provider-glow: rgba(5, 150, 105, 0.15);
  --color-member: #2563eb; /* Electric Blue */
  --color-member-glow: rgba(37, 99, 235, 0.15);

  --color-danger: #dc2626;
  --color-warning: #d97706;
  --color-success: #059669;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-main);
  background-image: 
    radial-gradient(at 0% 0%, rgba(99, 102, 241, 0.04) 0px, transparent 50%),
    radial-gradient(at 100% 100%, rgba(16, 185, 129, 0.04) 0px, transparent 50%);
  color: var(--text-main);
  min-height: 100vh;
  line-height: 1.5;
}

/* Navbar - Preserved Sleek Dark Header */
.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 2rem;
  background: #0f172a;
  border-bottom: 1px solid #1e293b;
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 4px 20px rgba(15, 23, 42, 0.15);
}

.brand {
  font-size: 1.4rem;
  font-weight: 700;
  background: linear-gradient(135deg, #60a5fa, #34d399);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  text-decoration: none;
}

.user-nav {
  display: flex;
  align-items: center;
  gap: 1.2rem;
  color: #f8fafc;
}

.role-badge {
  padding: 0.25rem 0.75rem;
  border-radius: 9999px;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.role-admin {
  background: rgba(99, 102, 241, 0.2);
  color: #818cf8;
  border: 1px solid rgba(99, 102, 241, 0.4);
}

.role-provider {
  background: rgba(16, 185, 129, 0.2);
  color: #34d399;
  border: 1px solid rgba(16, 185, 129, 0.4);
}

.role-member {
  background: rgba(59, 130, 246, 0.2);
  color: #60a5fa;
  border: 1px solid rgba(59, 130, 246, 0.4);
}

.btn-logout {
  background: rgba(239, 68, 68, 0.15);
  color: #f87171;
  border: 1px solid rgba(239, 68, 68, 0.3);
  padding: 0.4rem 0.9rem;
  border-radius: 8px;
  text-decoration: none;
  font-size: 0.85rem;
  font-weight: 500;
  transition: all 0.2s ease;
}

.btn-logout:hover {
  background: rgba(239, 68, 68, 0.3);
}

/* Container */
.container {
  max-width: 1280px;
  margin: 2rem auto;
  padding: 0 1.5rem;
}

/* Page Header */
.page-header {
  margin-bottom: 2rem;
}

.page-title {
  font-size: 1.8rem;
  font-weight: 700;
  color: #0f172a;
  margin-bottom: 0.4rem;
}

.page-subtitle {
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* White Cards */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 1.5rem;
  margin-bottom: 1.5rem;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
}

/* Alert Messages */
.alert {
  padding: 1rem 1.2rem;
  border-radius: 12px;
  margin-bottom: 1.5rem;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.alert-success {
  background: #ecfdf5;
  border: 1px solid #a7f3d0;
  color: #047857;
}

.alert-error {
  background: #fef2f2;
  border: 1px solid #fecaca;
  color: #b91c1c;
}

.alert-info {
  background: #eff6ff;
  border: 1px solid #bfdbfe;
  color: #1d4ed8;
}

/* Form Inputs */
.form-group {
  margin-bottom: 1.2rem;
}

.form-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: #475569;
  margin-bottom: 0.4rem;
}

.form-control, .form-select {
  width: 100%;
  padding: 0.65rem 0.9rem;
  background: #ffffff;
  border: 1px solid #cbd5e1;
  border-radius: 10px;
  color: #0f172a;
  font-family: inherit;
  font-size: 0.9rem;
  transition: all 0.2s ease;
}

.form-control:focus, .form-select:focus {
  outline: none;
  border-color: #3b82f6;
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.65rem 1.2rem;
  border-radius: 10px;
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: all 0.2s ease;
  text-decoration: none;
}

.btn-primary {
  background: linear-gradient(135deg, #3b82f6, #2563eb);
  color: #fff;
  box-shadow: 0 4px 14px rgba(59, 130, 246, 0.25);
}

.btn-primary:hover {
  opacity: 0.95;
  transform: translateY(-1px);
}

.btn-success {
  background: linear-gradient(135deg, #10b981, #059669);
  color: #fff;
  box-shadow: 0 4px 14px rgba(16, 185, 129, 0.25);
}

.btn-danger {
  background: #fef2f2;
  color: #dc2626;
  border: 1px solid #fecaca;
}

.btn-danger:hover {
  background: #fee2e2;
}

.btn-secondary {
  background: #f1f5f9;
  color: #334155;
  border: 1px solid #cbd5e1;
}

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

/* Tables */
.table-responsive {
  width: 100%;
  overflow-x: auto;
}

.table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.9rem;
}

.table th {
  background: #f8fafc;
  color: #475569;
  font-weight: 600;
  padding: 0.85rem 1rem;
  border-bottom: 2px solid #e2e8f0;
}

.table td {
  padding: 0.85rem 1rem;
  border-bottom: 1px solid #f1f5f9;
  color: #1e293b;
  vertical-align: middle;
}

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

/* Badges */
.badge {
  padding: 0.25rem 0.6rem;
  border-radius: 6px;
  font-size: 0.75rem;
  font-weight: 600;
}

.badge-doctor { background: #f3e8ff; color: #7e22ce; border: 1px solid #e9d5ff; }
.badge-nurse { background: #eff6ff; color: #1d4ed8; border: 1px solid #bfdbfe; }
.badge-dietician { background: #ecfdf5; color: #047857; border: 1px solid #a7f3d0; }
.badge-instructor { background: #fffbeb; color: #b45309; border: 1px solid #fde68a; }
.badge-officer { background: #fdf2f8; color: #be185d; border: 1px solid #fbcfe8; }

/* Weekly Availability Grid */
.weekly-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1rem;
}

.day-card {
  background: #f8fafc;
  border: 1px solid #e2e8f0;
  border-radius: 12px;
  padding: 1rem;
}

.day-card.today {
  border-color: #10b981;
  box-shadow: 0 0 15px rgba(16, 185, 129, 0.15);
  background: #ffffff;
}

.day-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.8rem;
}

.day-name {
  font-weight: 700;
  font-size: 1rem;
  color: #0f172a;
}

.day-date {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* Tabs */
.tabs {
  display: flex;
  gap: 0.5rem;
  border-bottom: 2px solid #e2e8f0;
  margin-bottom: 1.5rem;
}

.tab-btn {
  background: none;
  border: none;
  color: #64748b;
  padding: 0.75rem 1.2rem;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  border-bottom: 3px solid transparent;
  transition: all 0.2s ease;
}

.tab-btn.active {
  color: #4f46e5;
  border-bottom-color: #4f46e5;
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
}

/* Grid layout for filters */
.filter-bar {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)) auto;
  gap: 1rem;
  align-items: end;
}