:root {
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --secondary: #f1f5f9;
    --secondary-hover: #e2e8f0;
    --danger: #ef4444;
    --danger-hover: #dc2626;
    --success: #10b981;
    --dark: #0f172a;
    --text: #334155;
    --text-light: #64748b;
    --bg-color: #f8fafc;
    --white: #ffffff;
    --border: #e2e8f0;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --radius: 8px;
}

/* ==========================================
   DARK THEME VARIABLES & OVERRIDES
   ========================================== */
body.dark-theme {
    --bg-color: #0f172a;
    --white: #1e293b;
    --text: #f1f5f9;
    --text-light: #94a3b8;
    --border: #334155;
    --secondary: #334155;
    --secondary-hover: #475569;
    --dark: #f8fafc;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.5);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.5);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
}

body.dark-theme input, 
body.dark-theme select, 
body.dark-theme textarea {
    background: #0f172a;
    color: #f1f5f9;
}

/* Theme Toggle Button */
.theme-toggle {
    position: fixed;
    bottom: 20px;
    left: 20px;
    background: var(--white);
    color: var(--text);
    border: 1px solid var(--border);
    border-radius: 50%;
    width: 45px;
    height: 45px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    cursor: pointer;
    box-shadow: var(--shadow-md);
    z-index: 9999;
    transition: all 0.3s ease;
}
.theme-toggle:hover {
    transform: scale(1.1);
}

* { box-sizing: border-box; margin: 0; padding: 0; font-family: 'Inter', sans-serif; }
body { background-color: var(--bg-color); color: var(--text); line-height: 1.5; transition: background-color 0.3s, color 0.3s; }
.hidden { display: none !important; }
.mt-4 { margin-top: 1.5rem; }

/* --- Buttons --- */
.btn { display: inline-flex; align-items: center; justify-content: center; padding: 0.6rem 1.2rem; font-size: 0.9rem; font-weight: 500; border: none; border-radius: var(--radius); cursor: pointer; transition: all 0.2s ease; gap: 8px; }
.btn-block { width: 100%; }
.btn-sm { padding: 0.4rem 0.8rem; font-size: 0.85rem; }
.btn-primary { background: var(--primary); color: #ffffff; }
.btn-primary:hover { background: var(--primary-hover); }
.btn-secondary { background: var(--secondary); color: var(--text); border: 1px solid var(--border); }
.btn-secondary:hover { background: var(--secondary-hover); }
.btn-danger { background: var(--danger); color: #ffffff; }
.btn-danger:hover { background: var(--danger-hover); }

/* --- Loaders --- */
.loader-overlay { position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.3); backdrop-filter: blur(2px); display: flex; justify-content: center; align-items: center; z-index: 9999; }
.spinner { border: 4px solid var(--secondary); border-top: 4px solid var(--primary); border-radius: 50%; width: 40px; height: 40px; animation: spin 1s linear infinite; }
@keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }

/* --- Toasts --- */
.toast-container { position: fixed; bottom: 20px; right: 20px; z-index: 9999; display: flex; flex-direction: column; gap: 10px; }
.toast { padding: 15px 20px; border-radius: var(--radius); color: white; font-weight: 500; box-shadow: var(--shadow-lg); transform: translateX(100%); opacity: 0; transition: all 0.3s cubic-bezier(0.68, -0.55, 0.265, 1.55); display: flex; align-items: center; gap: 10px; }
.toast.show { transform: translateX(0); opacity: 1; }
.toast.success { background: var(--success); }
.toast.error { background: var(--danger); }

/* --- Modals --- */
.modal { position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.5); display: flex; justify-content: center; align-items: center; z-index: 1000; backdrop-filter: blur(2px); }
.modal-content { background: var(--white); padding: 25px; border-radius: var(--radius); width: 90%; max-width: 400px; box-shadow: var(--shadow-lg); animation: slideDown 0.3s ease; }
@keyframes slideDown { from { transform: translateY(-20px); opacity: 0; } to { transform: translateY(0); opacity: 1; } }
.modal-header h3 { display: flex; align-items: center; gap: 10px; font-size: 1.2rem; color: var(--dark); margin-bottom: 15px; }
.warning-icon { color: #f59e0b; }
.modal-body { color: var(--text-light); margin-bottom: 25px; font-size: 0.95rem; }
.modal-footer { display: flex; justify-content: flex-end; gap: 10px; }

/* --- Auth Section --- */
.auth-container { height: 100vh; display: flex; align-items: center; justify-content: center; padding: 20px; }
.auth-box { background: var(--white); padding: 40px; border-radius: 16px; box-shadow: var(--shadow-lg); width: 100%; max-width: 400px; text-align: center; border: 1px solid var(--border); }
.auth-icon { font-size: 2.5rem; color: var(--primary); margin-bottom: 10px; }
.auth-box h2 { color: var(--dark); margin-bottom: 5px; }
.auth-box p { color: var(--text-light); margin-bottom: 25px; font-size: 0.9rem; }

/* --- Forms --- */
.form-group { margin-bottom: 1rem; text-align: left; }
.form-group label { display: block; margin-bottom: 0.5rem; font-size: 0.85rem; font-weight: 500; color: var(--text); }
.form-group input, .form-group select, .form-group textarea { width: 100%; padding: 0.6rem 1rem; border: 1px solid var(--border); border-radius: var(--radius); font-size: 0.95rem; color: var(--dark); transition: border-color 0.2s; background: var(--white); }
.form-group input:focus, .form-group select:focus, .form-group textarea:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1); }
.form-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 1rem; }

/* --- App Layout (Sidebar + Main) --- */
.app-wrapper { display: flex; min-height: 100vh; }
.sidebar { width: 260px; background: var(--white); border-right: 1px solid var(--border); display: flex; flex-direction: column; position: fixed; height: 100vh; z-index: 100; transition: transform 0.3s ease; }
.sidebar-header { padding: 20px; border-bottom: 1px solid var(--border); display: flex; justify-content: space-between; align-items: center; }
.sidebar-header h2 { color: var(--primary); font-size: 1.2rem; display: flex; align-items: center; gap: 10px; }
.close-sidebar { display: none; background: none; border: none; font-size: 1.2rem; color: var(--text-light); cursor: pointer; }
.nav-links { list-style: none; padding: 20px 15px; flex-grow: 1; }
.nav-item { display: flex; align-items: center; gap: 10px; padding: 12px 15px; text-decoration: none; color: var(--text); border-radius: var(--radius); margin-bottom: 5px; font-weight: 500; transition: background 0.2s; }
.nav-item:hover { background: var(--secondary); }
.nav-item.active { background: var(--primary); color: #ffffff; }
.sidebar-footer { padding: 20px; border-top: 1px solid var(--border); }

.main-content { flex-grow: 1; margin-left: 260px; padding: 30px; max-width: 1200px; width: 100%; }
.mobile-header { display: none; padding: 15px 20px; background: var(--white); border-bottom: 1px solid var(--border); align-items: center; gap: 15px; position: sticky; top: 0; z-index: 90; }
.hamburger { background: none; border: none; font-size: 1.2rem; cursor: pointer; color: var(--dark); }

/* --- Dashboard & Filters --- */
.stats-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 20px; margin-bottom: 25px; }
.stat-card { background: var(--white); padding: 20px; border-radius: var(--radius); box-shadow: var(--shadow-sm); display: flex; align-items: center; gap: 15px; border: 1px solid var(--border); }
.stat-icon { width: 48px; height: 48px; border-radius: 12px; background: #eff6ff; color: var(--primary); display: flex; justify-content: center; align-items: center; font-size: 1.5rem; }
.stat-icon.active-icon { background: #ecfdf5; color: var(--success); }
.stat-card h3 { font-size: 0.85rem; color: var(--text-light); font-weight: 500; }
.stat-card h2 { font-size: 1.5rem; color: var(--dark); }

/* --- Category Stats --- */
.category-stats-card { background: var(--white); padding: 20px; border-radius: var(--radius); box-shadow: var(--shadow-sm); border: 1px solid var(--border); margin-bottom: 25px; }
.category-stats-card h3 { font-size: 1rem; color: var(--dark); margin-bottom: 15px; display: flex; align-items: center; gap: 8px; }
.category-stats-list { display: flex; flex-wrap: wrap; gap: 10px; }
.cat-stat-pill { background: var(--bg-color); color: var(--text); padding: 6px 12px; border-radius: 20px; font-size: 0.85rem; font-weight: 500; border: 1px solid var(--border); display: flex; align-items: center; gap: 8px; }
.cat-stat-count { background: var(--primary); color: #ffffff; border-radius: 50%; min-width: 20px; height: 20px; padding: 0 6px; display: flex; align-items: center; justify-content: center; font-size: 0.75rem; font-weight: bold; }

.filter-card { background: var(--white); padding: 20px; border-radius: var(--radius); box-shadow: var(--shadow-sm); border: 1px solid var(--border); margin-bottom: 25px; }
.filter-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 15px; }
.filter-grid .form-group { margin-bottom: 0; }
.filter-actions { display: flex; justify-content: flex-end; margin-top: 15px; }

/* --- Provider Cards --- */
.provider-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 20px; }
.provider-card { background: var(--white); border-radius: var(--radius); box-shadow: var(--shadow-sm); border: 1px solid var(--border); display: flex; flex-direction: column; overflow: hidden; transition: transform 0.2s, box-shadow 0.2s; }
.provider-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.card-header { padding: 20px; border-bottom: 1px solid var(--border); display: flex; justify-content: space-between; align-items: flex-start; }
.card-header h3 { color: var(--dark); font-size: 1.1rem; margin-bottom: 5px; }
.badge { font-size: 0.75rem; font-weight: 600; padding: 4px 8px; border-radius: 20px; white-space: nowrap; }
.badge-cat { background: var(--primary); color: #ffffff; }
.badge-active { background: var(--success); color: #ffffff; }
.badge-inactive { background: var(--danger); color: #ffffff; }
.card-body { padding: 20px; flex-grow: 1; font-size: 0.9rem; color: var(--text); display: flex; flex-direction: column; gap: 10px; }
.info-row { display: flex; align-items: flex-start; gap: 10px; }
.info-row i { color: var(--text-light); width: 16px; margin-top: 3px; }
.info-row a { color: var(--primary); text-decoration: none; }
.info-row a:hover { text-decoration: underline; }
.card-notes { background: var(--secondary); padding: 10px; border-radius: 6px; font-size: 0.85rem; font-style: italic; margin-top: 10px; }
.card-footer { padding: 15px 20px; background: var(--bg-color); border-top: 1px solid var(--border); display: flex; gap: 10px; }

.empty-state { text-align: center; padding: 40px 20px; color: var(--text-light); }
.empty-state i { font-size: 3rem; margin-bottom: 15px; color: var(--border); }

.form-card { background: var(--white); padding: 30px; border-radius: var(--radius); box-shadow: var(--shadow-sm); border: 1px solid var(--border); max-width: 800px; margin: 0 auto; }
.form-header { margin-bottom: 25px; border-bottom: 1px solid var(--border); padding-bottom: 15px; }
.form-header p { color: var(--text-light); font-size: 0.9rem; }

/* Responsive */
@media (max-width: 900px) {
    .sidebar { transform: translateX(-100%); }
    .sidebar.open { transform: translateX(0); }
    .main-content { margin-left: 0; padding: 15px; }
    .mobile-header { display: flex; }
    .close-sidebar { display: block; }
}