:root {
  --primary: #0ea5e9; --primary-d: #075985; --primary-l: #f0f9ff; --primary-b: #bae6fd;
  --bg: #f4f8fb; --card: #fff; --ink: #1f2933; --muted: #6b7280; --line: #e2e8f0;
  --red: #dc2626; --amber: #f59e0b;
}
* { box-sizing: border-box; }
body { margin: 0; font-family: "Segoe UI", system-ui, Arial, sans-serif; background: var(--bg); color: var(--ink); }
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.topbar { background: var(--primary-d); color: #fff; padding: 0 22px; display: flex; align-items: center; gap: 26px; height: 56px; position: relative; }
.topbar .brand { font-weight: 700; font-size: 17px; letter-spacing: .3px; }
.topbar .brand span { color: #7dd3fc; }
.topbar nav { display: flex; gap: 18px; position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%); }
.topbar nav a { color: #bae6fd; font-size: 14px; font-weight: 500; }
.topbar nav a:hover, .topbar nav a.active { color: #fff; text-decoration: none; }
.topbar .spacer { flex: 1; }
.topbar .logout { color: #7dd3fc; font-size: 13px; }

.wrap { max-width: 1100px; margin: 24px auto; padding: 0 22px; }
h1 { font-size: 22px; color: var(--primary-d); margin: 0 0 4px; text-align: center; }
h1 + .sub { text-align: center; }
h2 { font-size: 16px; color: var(--primary-d); margin: 26px 0 10px; }
.sub { color: var(--muted); margin: 0 0 18px; font-size: 14px; }

.cards { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; margin-bottom: 8px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 16px 18px; }
.card .k { font-size: 11px; text-transform: uppercase; letter-spacing: .6px; color: var(--muted); font-weight: 700; }
.card .v { font-size: 28px; font-weight: 700; color: var(--primary-d); margin-top: 4px; }
.card .v.warn { color: var(--amber); } .card .v.bad { color: var(--red); }
a.card { color: var(--ink); }

/* Wi-Fi signal bars (fleet dashboard) */
.wifi-bars { display: inline-flex; align-items: flex-end; gap: 2px; height: 14px; }
.wifi-bars .wb { width: 4px; border-radius: 1px; background: var(--line); }
.wifi-bars .wb:nth-child(1) { height: 30%; }
.wifi-bars .wb:nth-child(2) { height: 53%; }
.wifi-bars .wb:nth-child(3) { height: 76%; }
.wifi-bars .wb:nth-child(4) { height: 100%; }
.wifi-bars .wb.on { background: var(--primary); }
.wifi-na { color: var(--muted); font-size: 12px; }
#remove-selected { background: none; border: 1px solid var(--red); color: var(--red); font-size: 13px; cursor: pointer; padding: 5px 12px; border-radius: 6px; font-family: inherit; }
#remove-selected:hover { background: var(--red); color: #fff; }
#remove-selected:disabled { opacity: .6; cursor: default; }
a.card:hover { border-color: var(--primary); text-decoration: none; }
.card-active { border-color: var(--primary); background: var(--primary-l); }

.panel { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 4px 18px 14px; margin-bottom: 18px; }

table { width: 100%; border-collapse: collapse; font-size: 13.5px; }
th, td { text-align: left; padding: 9px 10px; border-bottom: 1px solid var(--line); vertical-align: middle; }
th { font-size: 11px; text-transform: uppercase; letter-spacing: .5px; color: var(--muted); }
tbody tr:hover { background: #fafafa; }

.badge { display: inline-block; font-size: 11px; font-weight: 700; padding: 3px 9px; border-radius: 20px; text-transform: uppercase; letter-spacing: .3px; }
.s-online { background: #dcfce7; color: #166534; }
.s-offline { background: #fee2e2; color: #991b1b; }
.s-never { background: #e5e7eb; color: #374151; }
.s-alerted { background: #fef3c7; color: #92400e; }  /* offline alert sent (app/monitor.py) */
.dot { display:inline-block; width:8px; height:8px; border-radius:50%; margin-right:6px; vertical-align: middle; }
.dot.online{background:#16a34a;} .dot.offline{background:var(--red);} .dot.never{background:#9ca3af;}

.btn { display: inline-block; background: var(--primary); color: #fff; border: none; border-radius: 8px; padding: 8px 14px; font-size: 13.5px; font-weight: 600; cursor: pointer; }
.btn:hover { background: #0284c7; text-decoration: none; }
.btn.sec { background: #fff; color: var(--primary-d); border: 1px solid var(--primary-b); }
.btn.gray { background: #6b7280; } .btn.gray:hover { background: #4b5563; }
.btn.sm { padding: 5px 10px; font-size: 12.5px; }

input, select, textarea { font: inherit; padding: 8px 10px; border: 1px solid #cbd5e1; border-radius: 8px; background: #fff; }
label { font-size: 13px; color: var(--muted); font-weight: 600; display: block; margin: 8px 0 3px; }
.row { display: flex; gap: 10px; align-items: flex-end; flex-wrap: wrap; }
.mono { font-family: ui-monospace, "Cascadia Code", Consolas, monospace; font-size: 12.5px; }
.muted { color: var(--muted); }

.login-box { max-width: 340px; margin: 12vh auto; background: #fff; border: 1px solid var(--line); border-radius: 14px; padding: 26px; }
.login-box h1 { text-align: center; }
.login-box input { width: 100%; }
.err { color: var(--red); font-size: 13px; margin: 8px 0; }

input.cell-edit { border: 1px solid transparent; background: transparent; padding: 4px 6px; font: inherit; border-radius: 4px; }
input.cell-edit:hover { border-color: #cbd5e1; background: #fff; }
input.cell-edit:focus { border-color: var(--primary); background: #fff; outline: none; box-shadow: 0 0 0 2px rgba(14,165,233,.18); }

th.sortable { cursor: pointer; user-select: none; white-space: nowrap; }
th.sortable:hover { color: var(--primary-d); }
.sort-arrow { font-size: 10px; margin-left: 3px; opacity: .35; }
th.sortable.asc .sort-arrow::after { content: "▲"; opacity: 1; }
th.sortable.desc .sort-arrow::after { content: "▼"; opacity: 1; }
th.sortable:not(.asc):not(.desc) .sort-arrow::after { content: "▲▼"; font-size: 8px; letter-spacing: -2px; }
th.sortable.asc .sort-arrow, th.sortable.desc .sort-arrow { opacity: 1; }