:root {
  --bg: #f5f6f8;
  --surface: #ffffff;
  --surface-alt: #f0f1f4;
  --border: #dfe2e8;
  --text: #1a1d24;
  --text-muted: #666d7a;
  --accent: #2f6feb;
  --accent-contrast: #ffffff;
  --danger: #c0392b;
  --danger-bg: #fdecea;
  --success: #1e8e5a;
  --success-bg: #e8f7ef;
  --warning: #b7791f;
  --warning-bg: #fef6e7;
  color-scheme: light;
}

:root[data-theme="dark"] {
  --bg: #14161b;
  --surface: #1c1f26;
  --surface-alt: #22262f;
  --border: #2c313c;
  --text: #e8e9ed;
  --text-muted: #9aa1ad;
  --accent: #6699ff;
  --accent-contrast: #0b0d10;
  --danger: #ff6b5e;
  --danger-bg: #3a1f1c;
  --success: #4fd18b;
  --success-bg: #113228;
  --warning: #e0b04a;
  --warning-bg: #3a2f14;
  color-scheme: dark;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #14161b;
    --surface: #1c1f26;
    --surface-alt: #22262f;
    --border: #2c313c;
    --text: #e8e9ed;
    --text-muted: #9aa1ad;
    --accent: #6699ff;
    --accent-contrast: #0b0d10;
    --danger: #ff6b5e;
    --danger-bg: #3a1f1c;
    --success: #4fd18b;
    --success-bg: #113228;
    --warning: #e0b04a;
    --warning-bg: #3a2f14;
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans Bengali", Arial, sans-serif;
  font-size: 14px;
  line-height: 1.5;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

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

.sidebar {
  width: 220px;
  flex-shrink: 0;
  background: var(--surface);
  border-right: 1px solid var(--border);
  padding: 16px 0;
  display: flex;
  flex-direction: column;
}

.sidebar .brand {
  padding: 0 20px 16px;
  font-weight: 700;
  font-size: 16px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 12px;
}

.sidebar .brand small {
  display: block;
  font-weight: 400;
  color: var(--text-muted);
  font-size: 12px;
}

.nav-item {
  display: block;
  padding: 10px 20px;
  color: var(--text);
  border-left: 3px solid transparent;
}

.nav-item:hover { background: var(--surface-alt); text-decoration: none; }

.nav-item.active {
  border-left-color: var(--accent);
  background: var(--surface-alt);
  font-weight: 600;
}

.nav-item.disabled {
  color: var(--text-muted);
  cursor: default;
  pointer-events: none;
  opacity: 0.55;
}

.nav-section-label {
  padding: 14px 20px 4px;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
}

.main {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 24px;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}

.topbar .title { font-size: 18px; font-weight: 600; }
.topbar .user { display: flex; align-items: center; gap: 12px; color: var(--text-muted); font-size: 13px; }

.content { padding: 24px; flex: 1; }

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 18px;
  margin-bottom: 18px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 16px;
}

.stat .label { color: var(--text-muted); font-size: 12px; margin-bottom: 6px; }
.stat .value { font-size: 26px; font-weight: 700; }
.stat .sub { color: var(--text-muted); font-size: 12px; margin-top: 4px; }

table { width: 100%; border-collapse: collapse; }
th, td { text-align: left; padding: 8px 10px; border-bottom: 1px solid var(--border); font-size: 13px; vertical-align: middle; }
th { color: var(--text-muted); font-weight: 600; font-size: 12px; text-transform: uppercase; letter-spacing: 0.03em; }
tr:hover td { background: var(--surface-alt); }

.badge {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 999px;
  font-size: 11px;
  font-weight: 600;
}
.badge.active { background: var(--success-bg); color: var(--success); }
.badge.paused { background: var(--warning-bg); color: var(--warning); }
.badge.pending { background: var(--warning-bg); color: var(--warning); }
.badge.approved { background: var(--success-bg); color: var(--success); }
.badge.rejected { background: var(--danger-bg); color: var(--danger); }
.badge.alert { background: var(--danger-bg); color: var(--danger); }

.btn {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--surface-alt);
  color: var(--text);
  font-size: 13px;
  cursor: pointer;
}
.btn:hover { filter: brightness(1.05); text-decoration: none; }
.btn.primary { background: var(--accent); border-color: var(--accent); color: var(--accent-contrast); }
.btn.danger { background: var(--danger); border-color: var(--danger); color: #fff; }
.btn.success { background: var(--success); border-color: var(--success); color: #fff; }
.btn.small { padding: 4px 10px; font-size: 12px; }

input, select, textarea {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 6px;
  padding: 8px 10px;
  font-size: 13px;
  width: 100%;
}

.form-row { margin-bottom: 12px; }
.form-row label { display: block; margin-bottom: 4px; font-size: 12px; color: var(--text-muted); }
.form-inline { display: flex; gap: 8px; align-items: flex-end; flex-wrap: wrap; }
.form-inline .form-row { margin-bottom: 0; flex: 1; min-width: 160px; }

.flash { padding: 10px 14px; border-radius: 8px; margin-bottom: 16px; font-size: 13px; }
.flash.ok { background: var(--success-bg); color: var(--success); }
.flash.error { background: var(--danger-bg); color: var(--danger); }

.muted { color: var(--text-muted); }
.mt-0 { margin-top: 0; }

.login-wrap {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg);
}
.login-card {
  width: 320px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 28px;
}
.login-card h1 { font-size: 18px; margin: 0 0 4px; }
.login-card p.sub { color: var(--text-muted); font-size: 12px; margin: 0 0 20px; }

.theme-toggle {
  background: none;
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 4px 10px;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 12px;
}

.bn { color: var(--text-muted); font-size: 0.92em; }