:root {
  --bg: #f5f7fb;
  --surface: #ffffff;
  --ink: #1f2937;
  --muted: #6b7280;
  --line: #d1d5db;
  --accent: #0f766e;
  --error: #b91c1c;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: "Segoe UI", "Noto Sans", sans-serif;
  color: var(--ink);
  background: var(--bg);
}

.container {
  width: min(1100px, 94%);
  margin: 0 auto;
}

.topbar {
  background: #0b1324;
  color: #fff;
  border-bottom: 1px solid #111827;
}

.topbar-inner {
  min-height: 56px;
  display: flex;
  align-items: center;
  gap: 18px;
}

.brand {
  font-weight: 700;
  letter-spacing: 0.2px;
}

.nav {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.nav a {
  color: #dbeafe;
  text-decoration: none;
  font-size: 14px;
}

.nav a:hover { color: #ffffff; }

.logout-form { margin-left: auto; }

.main { padding: 20px 0 28px; }

h1 {
  margin: 0 0 14px;
  font-size: 24px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 14px;
  margin-bottom: 14px;
  overflow-x: auto;
}

.grid {
  display: grid;
  gap: 12px;
  margin-bottom: 14px;
}

.cols-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }

.stat .label {
  font-size: 13px;
  color: var(--muted);
}

.stat .value {
  font-size: 24px;
  font-weight: 700;
}

label {
  font-size: 14px;
  color: var(--ink);
}

input, select, button {
  font-size: 14px;
  padding: 8px 10px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
}

button {
  cursor: pointer;
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

button[disabled] {
  opacity: 0.6;
  cursor: not-allowed;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}

th, td {
  padding: 8px;
  border-bottom: 1px solid #e5e7eb;
  text-align: left;
  vertical-align: top;
}

th { color: var(--muted); font-weight: 600; }

.form-grid {
  display: grid;
  gap: 10px;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  align-items: center;
}

.error {
  color: var(--error);
  margin: 0 0 10px;
}

.login-body {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(180deg, #edf2ff, #f8fafc);
}

.login-card {
  width: min(420px, 92%);
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 18px;
}

.login-card h1 { margin-top: 0; }

.login-card form {
  display: grid;
  gap: 8px;
}

@media (max-width: 900px) {
  .cols-4, .cols-3 { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 600px) {
  .cols-4, .cols-3 { grid-template-columns: 1fr; }
  .topbar-inner { flex-wrap: wrap; padding: 8px 0; }
  .logout-form { margin-left: 0; }
}