:root {
  --bg: #f4f6f9;
  --sidebar-bg: #1e293b;
  --sidebar-text: #cbd5e1;
  --sidebar-active: #38bdf8;
  --accent: #0ea5e9;
  --border: #e2e8f0;
  --text: #1e293b;
  --muted: #64748b;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--text);
  background: var(--bg);
}

.layout {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar {
  width: 240px;
  background: var(--sidebar-bg);
  color: var(--sidebar-text);
  padding: 1.5rem 1rem;
  flex-shrink: 0;
}

.logo {
  font-size: 1.25rem;
  margin: 0 0 2rem;
  color: #fff;
}

.sidebar nav {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.nav-link {
  display: block;
  padding: 0.65rem 0.8rem;
  border-radius: 8px;
  color: var(--sidebar-text);
  text-decoration: none;
  font-size: 0.95rem;
  transition: background 0.15s, color 0.15s;
}

.nav-link:hover {
  background: rgba(255, 255, 255, 0.06);
  color: #fff;
}

.nav-link.active {
  background: rgba(56, 189, 248, 0.15);
  color: var(--sidebar-active);
  font-weight: 600;
}

/* Content */
.content {
  flex: 1;
  padding: 2rem 2.5rem;
  overflow-x: auto;
}

.page h2 {
  margin-top: 0;
}

.muted {
  color: var(--muted);
}

/* Filters */
.filters {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.filters label,
.form label {
  display: flex;
  flex-direction: column;
  font-size: 0.85rem;
  color: var(--muted);
  gap: 0.3rem;
}

.filters select,
.form input {
  padding: 0.5rem 0.6rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 0.95rem;
  background: #fff;
  color: var(--text);
}

/* Table */
.table-wrapper {
  overflow-x: auto;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 10px;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

thead th {
  text-align: left;
  padding: 0.7rem 0.9rem;
  background: #f1f5f9;
  border-bottom: 1px solid var(--border);
  cursor: pointer;
  white-space: nowrap;
  user-select: none;
}

thead th:hover {
  color: var(--accent);
}

tbody td {
  padding: 0.6rem 0.9rem;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}

tbody tr:last-child td {
  border-bottom: none;
}

tbody tr:hover {
  background: #f8fafc;
}

/* Form */
.form {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
  max-width: 700px;
  background: #fff;
  padding: 1.5rem;
  border: 1px solid var(--border);
  border-radius: 10px;
}

.form button {
  grid-column: 1 / -1;
  justify-self: start;
  padding: 0.65rem 1.5rem;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 8px;
  font-size: 0.95rem;
  cursor: pointer;
}

.form button:hover {
  background: #0284c7;
}

.feedback {
  margin-top: 1rem;
  padding: 0.75rem 1rem;
  border-radius: 8px;
  max-width: 700px;
}

.feedback.success {
  background: #dcfce7;
  color: #166534;
}

.feedback.error {
  background: #fee2e2;
  color: #991b1b;
}

/* Charts */
.chart-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.25rem 1.5rem;
}

.chart-card h3 {
  margin: 0 0 1rem;
  font-size: 1rem;
}

.chart {
  width: 100%;
  height: 420px;
}