:root {
  --sidebar-bg: #0f172a;
  --sidebar-width: 270px;
  --header-bg: #0b1120;
  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --bg-color: #f8fafc;
  --card-bg: #ffffff;
  --text-primary: #334155;
  --text-muted: #64748b;
  --border-color: #e2e8f0;
}

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

body { font-family: 'Inter', sans-serif; background: var(--bg-color); color: var(--text-primary); height: 100vh; overflow: hidden; }

/* Layout */
.app-layout { display: flex; height: 100vh; }

/* Sidebar */
.sidebar {
  width: var(--sidebar-width);
  background: var(--sidebar-bg);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  overflow: hidden;
  transition: margin-left 0.3s ease, transform 0.3s ease;
}

/* Desktop Collapse */
@media (min-width: 769px) {
  .sidebar.collapsed {
    display: none !important;
  }
}

.sidebar-header {
  display: flex;
  align-items: center;
  padding: 12px 14px;
  background: var(--header-bg);
  border-bottom: 1px solid #2d2d44;
  min-height: 48px;
}

.server-tree {
  flex: 1;
  overflow-y: auto;
  padding: 12px 0;
}

/* Tree nodes */
.tree-server {
  color: #cbd5e1;
  font-size: 13.5px;
  font-weight: 500;
  padding: 8px 16px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 8px;
  border-left: 3px solid transparent;
  transition: all 0.2s ease;
}
.tree-server:hover { background: rgba(255, 255, 255, 0.05); color: #fff; }
.tree-server.active { border-left-color: var(--accent); background: rgba(59, 130, 246, 0.15); color: #fff; }
.tree-server .srv-actions { margin-left: auto; display: none; gap: 4px; }
.tree-server:hover .srv-actions { display: flex; }
.srv-actions button { background: none; border: none; color: #94a3b8; padding: 0 4px; font-size: 13px; cursor: pointer; transition: color 0.2s; }
.srv-actions button:hover { color: #fff; }

.tree-db {
  color: #93c5fd;
  font-size: 13px;
  padding: 6px 16px 6px 32px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all 0.2s;
}
.tree-db:hover { background: rgba(255, 255, 255, 0.05); color: #bfdbfe; }

.tree-category {
  color: #94a3b8;
  font-size: 11.5px;
  padding: 4px 16px 4px 46px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  transition: color 0.2s;
}
.tree-category:hover { color: #f8fafc; }

.tree-item {
  color: #86efac;
  font-size: 12.5px;
  padding: 4px 16px 4px 60px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all 0.2s;
}
.tree-item:hover { background: rgba(255, 255, 255, 0.05); color: #bbf7d0; }

/* Main area */
.main-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: #f4f6f9;
}

/* Tabs */
.app-tabs {
  background: #ffffff;
  border-bottom: 1px solid var(--border-color);
  padding: 0 16px;
  flex-shrink: 0;
  flex-wrap: nowrap;
  overflow-x: auto;
  overflow-y: hidden;
  scrollbar-width: none;
  box-shadow: 0 1px 3px rgba(0,0,0,0.02);
}
.app-tabs::-webkit-scrollbar { display: none; }

.app-tabs .nav-link {
  color: var(--text-muted);
  font-size: 13.5px;
  font-weight: 500;
  padding: 12px 16px;
  border: none;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
  white-space: nowrap;
  transition: all 0.2s ease;
}
.app-tabs .nav-link.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
  background: transparent;
  font-weight: 600;
}
.app-tabs .nav-link:hover:not(.active) { color: var(--text-primary); background: #f1f5f9; border-radius: 6px 6px 0 0; }

/* Mobile Responsive */
.sidebar-overlay {
  position: fixed; top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.5);
  z-index: 1030;
  display: none;
}
.sidebar-overlay.show { display: block; }

@media (max-width: 768px) {
  .sidebar {
    position: fixed;
    top: 0;
    bottom: 0;
    left: 0;
    height: 100vh;
    z-index: 1040;
    transform: translateX(-100%);
    transition: transform 0.3s ease;
    box-shadow: 2px 0 12px rgba(0,0,0,0.5);
  }
  .sidebar.show { 
    transform: translateX(0); 
  }
  .app-tabs { padding: 0 5px; }
  .app-tabs .nav-link { padding: 10px 8px; font-size: 12px; }
  .card-body { padding: 12px; }
}

/* Tab content */
.tab-content { flex: 1; overflow-y: auto; padding: 20px; }

/* Cards */
.card { border: 1px solid var(--border-color); box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03); border-radius: 12px; overflow: hidden; margin-bottom: 20px; }
.card-header { background: #f8fafc; border-bottom: 1px solid var(--border-color); font-weight: 600; padding: 12px 16px; color: #1e293b; }
.card-body { padding: 16px; }

/* Metric cards */
.card-metric { border: none; box-shadow: 0 4px 15px rgba(0,0,0,0.03); border-radius: 12px; background: linear-gradient(135deg, #ffffff 0%, #f8fafc 100%); border: 1px solid var(--border-color); transition: transform 0.2s, box-shadow 0.2s; }
.card-metric:hover { transform: translateY(-2px); box-shadow: 0 8px 25px rgba(0,0,0,0.06); }
.metric-label { font-size: 12.5px; font-weight: 500; color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.5px; margin-bottom: 8px; }
.metric-value { font-size: 26px; font-weight: 700; color: var(--accent); }

/* Query editor */
.query-editor {
  font-family: 'Consolas', 'Courier New', monospace;
  font-size: 14px;
  background: #0f172a;
  color: #e2e8f0;
  border: 1px solid #334155;
  border-radius: 8px;
  resize: vertical;
  min-height: 180px;
  padding: 12px;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.query-editor:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.25); }

/* Code box */
.code-box {
  background: #0f172a;
  color: #e2e8f0;
  font-family: 'Consolas', monospace;
  font-size: 13px;
  border-radius: 8px;
  padding: 16px;
  border: 1px solid #1e293b;
  white-space: pre-wrap;
  word-break: break-all;
}

/* Terminal */
.terminal-box { color: #86efac; min-height: 200px; }

/* Status badge */
#serverStatusBadge { font-size: 14px !important; padding: 6px 12px; border-radius: 20px; font-weight: 500; }

/* Buttons */
.btn { border-radius: 6px; font-weight: 500; transition: all 0.2s ease; }
.btn:active { transform: scale(0.97); }

/* Form Controls */
.form-control, .form-select { border-radius: 6px; border-color: #cbd5e1; }
.form-control:focus, .form-select:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15); }

/* Scrollbar */
::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: #cbd5e1; border-radius: 4px; border: 2px solid transparent; background-clip: padding-box; }
::-webkit-scrollbar-thumb:hover { background-color: #94a3b8; }

/* Table */
.table { font-size: 13.5px; }
.table thead th { font-size: 12.5px; color: #475569; font-weight: 600; background-color: #f1f5f9; border-bottom: 2px solid #e2e8f0; }
.table-hover tbody tr:hover { background-color: #f8fafc; }
/* Sidebar Links */
.sidebar-nav .nav-link {
  color: rgba(255, 255, 255, 0.75);
  padding: 10px 16px;
  border-radius: 6px;
  margin: 0 10px 4px 10px;
  font-size: 14px;
  transition: all 0.2s ease;
}
.sidebar-nav .nav-link:hover {
  color: #ffffff;
  background-color: rgba(255, 255, 255, 0.1);
}
.sidebar-nav .nav-link.active {
  color: #ffffff;
  background-color: var(--accent);
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}