:root {
  --bg: #f6f8fb;
  --surface: #ffffff;
  --surface-2: #f9fbff;
  --text: #152033;
  --muted: #6a7485;
  --line: #e4eaf2;
  --primary: #1f73ff;
  --primary-dark: #155fd6;
  --accent: #00a5a8;
  --danger: #d92d20;
  --success: #079455;
  --shadow: 0 16px 40px rgba(21, 32, 51, 0.08);
  --radius: 20px;
}

* { box-sizing: border-box; }
html { min-height: 100%; }
body {
  margin: 0;
  min-height: 100%;
  background: radial-gradient(circle at top left, #eaf2ff 0, transparent 34rem), var(--bg);
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

a { color: inherit; text-decoration: none; }
button, input, select, textarea { font: inherit; }

.shell { display: grid; grid-template-columns: 280px 1fr; min-height: 100vh; }
.sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  padding: 26px 20px;
  background: rgba(255, 255, 255, 0.86);
  border-right: 1px solid var(--line);
  backdrop-filter: blur(14px);
  display: flex;
  flex-direction: column;
  gap: 26px;
}
.brand { display: flex; align-items: center; gap: 12px; }
.brand-mark {
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  border-radius: 15px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  font-weight: 800;
  letter-spacing: -0.03em;
}
.brand strong { display: block; font-size: 1.1rem; }
.brand small { color: var(--muted); }
.nav { display: grid; gap: 8px; }
.nav a {
  padding: 12px 14px;
  border-radius: 14px;
  color: #40506a;
  font-weight: 650;
}
.nav a:hover, .nav a.active {
  background: #eef5ff;
  color: var(--primary-dark);
}
.sidebar-footer {
  margin-top: auto;
  display: flex;
  gap: 10px;
  align-items: center;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--surface-2);
  color: var(--muted);
  font-size: 0.92rem;
}
.status-dot { width: 10px; height: 10px; background: var(--success); border-radius: 50%; box-shadow: 0 0 0 4px rgba(7, 148, 85, 0.12); }

.main { padding: 30px; min-width: 0; }
.topbar {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 22px;
}
.eyebrow { margin: 0 0 6px; text-transform: uppercase; letter-spacing: 0.12em; font-weight: 800; color: var(--primary); font-size: 0.75rem; }
h1 { margin: 0; font-size: clamp(2rem, 4vw, 3.2rem); letter-spacing: -0.05em; }
h2 { margin: 0; font-size: 1.18rem; letter-spacing: -0.02em; }
p { color: var(--muted); }
.device-picker { min-width: 260px; }
.device-picker label { display: block; margin-bottom: 7px; font-size: 0.75rem; color: var(--muted); text-transform: uppercase; letter-spacing: 0.1em; font-weight: 800; }

.card {
  background: rgba(255, 255, 255, 0.92);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 22px;
  margin-bottom: 20px;
}
.card-header { display: flex; align-items: center; justify-content: space-between; gap: 16px; margin-bottom: 18px; }
.card-header p { margin: 6px 0 0; }
.card-header.compact { align-items: flex-start; }
.grid { display: grid; gap: 20px; }
.grid.stats { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid.two { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.settings-grid { grid-template-columns: 320px 1fr; align-items: start; }
.stat-card span { color: var(--muted); font-weight: 750; }
.stat-card strong { display: block; margin-top: 10px; font-size: 2.2rem; letter-spacing: -0.05em; }
.stat-card small { color: var(--muted); }

.flash-stack { display: grid; gap: 10px; margin-bottom: 20px; }
.flash { padding: 13px 16px; border-radius: 14px; border: 1px solid var(--line); background: #fff; }
.flash.success { border-color: rgba(7, 148, 85, 0.22); background: #ecfdf3; color: #067647; }
.flash.warning { border-color: #fedf89; background: #fffaeb; color: #b54708; }
.flash.danger { border-color: #fecdca; background: #fef3f2; color: #b42318; }

input, select, textarea {
  width: 100%;
  border: 1px solid #d7dfeb;
  border-radius: 13px;
  background: #fff;
  padding: 11px 12px;
  color: var(--text);
  outline: none;
}
input:focus, select:focus, textarea:focus { border-color: var(--primary); box-shadow: 0 0 0 4px rgba(31, 115, 255, 0.10); }
input[type="checkbox"] { width: auto; }
input[type="color"] { height: 46px; padding: 5px; }
input[type="range"] { padding: 0; }
label { display: grid; gap: 7px; color: #344054; font-weight: 680; }
label.check { display: flex; align-items: center; gap: 8px; }
.form-row { display: flex; align-items: end; gap: 14px; flex-wrap: wrap; }
.form-row label { min-width: 160px; }
.form-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; align-items: end; }
.form-grid.wide { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.span-2 { grid-column: span 2; }
.form-actions { display: flex; justify-content: flex-end; gap: 10px; }
.compact-form { margin-bottom: 14px; }
.delete-row { display: flex; justify-content: flex-end; border-top: 1px solid var(--line); padding-top: 14px; }

.btn {
  border: 1px solid #cfd8e6;
  background: #fff;
  color: #344054;
  padding: 11px 15px;
  border-radius: 13px;
  cursor: pointer;
  font-weight: 800;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}
.btn:hover { transform: translateY(-1px); box-shadow: 0 10px 24px rgba(21, 32, 51, 0.10); }
.btn.primary { background: var(--primary); border-color: var(--primary); color: #fff; }
.btn.primary:hover { background: var(--primary-dark); }
.btn.danger { background: #fff; border-color: #fecdca; color: var(--danger); }
.btn.small { padding: 8px 11px; font-size: 0.86rem; border-radius: 11px; }
.button-row, .actions { display: flex; justify-content: flex-end; align-items: center; gap: 8px; flex-wrap: wrap; }
.inline-form { display: inline-flex; }

.table-wrap { width: 100%; overflow-x: auto; }
table { width: 100%; border-collapse: collapse; }
th { text-align: left; color: var(--muted); font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.08em; }
th, td { padding: 14px 12px; border-bottom: 1px solid var(--line); vertical-align: middle; }
td small { display: block; color: var(--muted); margin-top: 3px; }
.right { text-align: right; }
code { background: #eef2f7; padding: 4px 6px; border-radius: 8px; font-size: 0.82rem; }
.empty { color: var(--muted); text-align: center; padding: 28px; }
.empty-state { display: grid; place-items: center; min-height: 360px; text-align: center; }
.pill { display: inline-flex; align-items: center; padding: 5px 9px; border-radius: 999px; background: #eef2f7; color: #475467; font-weight: 800; font-size: 0.78rem; }
.pill.good { background: #ecfdf3; color: #067647; }
.pill.bad { background: #fef3f2; color: #b42318; }
.code-block { margin: 0; padding: 16px; background: #0f172a; color: #dbeafe; border-radius: 15px; overflow: auto; max-height: 520px; }
.quick-actions { display: grid; gap: 12px; }
.action-tile { display: grid; gap: 4px; padding: 16px; border-radius: 16px; border: 1px solid var(--line); background: var(--surface-2); }
.action-tile:hover { border-color: var(--primary); background: #eef5ff; }
.action-tile span, .list-item span { color: var(--muted); font-size: 0.9rem; }
.list-stack { display: grid; gap: 8px; }
.list-item { display: grid; gap: 4px; padding: 13px; border: 1px solid var(--line); border-radius: 14px; background: #fff; }
.list-item.active { border-color: var(--primary); background: #eef5ff; }

@media (max-width: 1100px) {
  .shell { grid-template-columns: 1fr; }
  .sidebar { position: static; height: auto; }
  .nav { grid-template-columns: repeat(3, 1fr); }
  .grid.stats, .grid.two, .settings-grid { grid-template-columns: 1fr; }
}

@media (max-width: 720px) {
  .main { padding: 18px; }
  .topbar, .card-header { flex-direction: column; align-items: stretch; }
  .form-grid { grid-template-columns: 1fr; }
  .span-2 { grid-column: span 1; }
  .nav { grid-template-columns: 1fr; }
}
.flash.info { border-color: #b9e6fe; background: #f0f9ff; color: #026aa2; }
.pill.api { background: #eef5ff; color: var(--primary-dark); }
.pill.mqtt { background: #f0fdfa; color: #0f766e; }
.transport-toggle {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px;
  padding: 6px;
  border: 1px solid var(--line);
  background: var(--surface-2);
  border-radius: 16px;
}
.transport-toggle label {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 42px;
  border-radius: 12px;
  cursor: pointer;
  color: var(--muted);
  font-weight: 850;
}
.transport-toggle input { display: none; }
.transport-toggle input:checked + span {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 8px 18px rgba(31, 115, 255, 0.18);
}
.transport-toggle span {
  display: flex;
  justify-content: center;
  align-items: center;
  width: 100%;
  height: 100%;
  padding: 10px 12px;
  border-radius: 12px;
}
.muted-note { color: var(--muted); font-size: 0.9rem; margin: 0; }
.device-meta { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; margin-top: 8px; }


/* Fleet health dashboard */
.fleet-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 20px;
}
.device-health-card {
  display: grid;
  gap: 16px;
  background: rgba(255, 255, 255, 0.94);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 22px;
  transition: transform 0.16s ease, box-shadow 0.16s ease, border-color 0.16s ease;
}
.device-health-card:hover {
  transform: translateY(-2px);
  border-color: rgba(31, 115, 255, 0.34);
  box-shadow: 0 18px 46px rgba(21, 32, 51, 0.12);
}
.device-health-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 14px;
}
.device-health-head h2 { margin-bottom: 4px; }
.device-health-head p { margin: 0; }
.device-meta { display: flex; gap: 7px; flex-wrap: wrap; align-items: center; }
.fresh-dot {
  width: 14px;
  height: 14px;
  flex: 0 0 14px;
  border-radius: 50%;
  background: #98a2b3;
  box-shadow: 0 0 0 5px rgba(152, 162, 179, 0.12);
  margin-top: 5px;
}
.fresh-dot.online { background: var(--success); box-shadow: 0 0 0 5px rgba(7, 148, 85, 0.14); }
.fresh-dot.stale { background: #f79009; box-shadow: 0 0 0 5px rgba(247, 144, 9, 0.14); }
.gauge-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}
.mini-gauge {
  --percent: 0%;
  --gauge-color: var(--primary);
  display: grid;
  place-items: center;
}
.gauge-ring {
  width: 92px;
  height: 92px;
  border-radius: 50%;
  background: conic-gradient(var(--gauge-color) var(--percent, 0%), #e8eef7 0);
  display: grid;
  place-items: center;
  position: relative;
}
.gauge-ring::after {
  content: "";
  position: absolute;
  inset: 10px;
  border-radius: 50%;
  background: #fff;
  box-shadow: inset 0 0 0 1px var(--line);
}
.gauge-ring strong,
.gauge-ring span {
  position: relative;
  z-index: 1;
  text-align: center;
}
.gauge-ring strong { display: block; font-size: 1.1rem; letter-spacing: -0.04em; color: var(--text); }
.gauge-ring span { display: block; color: var(--muted); font-size: 0.72rem; font-weight: 850; text-transform: uppercase; letter-spacing: 0.06em; }
.mini-gauge.large .gauge-ring { width: 132px; height: 132px; }
.mini-gauge.large .gauge-ring::after { inset: 14px; }
.mini-gauge.large .gauge-ring strong { font-size: 1.45rem; }
.health-details {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  padding-top: 12px;
  border-top: 1px solid var(--line);
}
.health-details span,
.metric-list span { color: var(--muted); font-size: 0.82rem; }
.health-details strong,
.metric-list strong { display: block; color: var(--text); margin-top: 3px; }
.empty-health {
  display: grid;
  gap: 6px;
  min-height: 150px;
  align-content: center;
  padding: 18px;
  border: 1px dashed #cfd8e6;
  border-radius: 16px;
  background: var(--surface-2);
  color: var(--muted);
}
.empty-health strong { color: var(--text); }
.large-empty { min-height: 300px; text-align: center; justify-items: center; }
.detail-hero {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(360px, 0.8fr);
  gap: 20px;
  align-items: start;
}
.detail-gauges { margin-bottom: 18px; }
.metric-list {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
}
.metric-list > div {
  padding: 13px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--surface-2);
}
@media (max-width: 1100px) {
  .detail-hero { grid-template-columns: 1fr; }
  .gauge-grid, .metric-list { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .health-details { grid-template-columns: 1fr; }
}
@media (max-width: 520px) {
  .fleet-grid { grid-template-columns: 1fr; }
  .gauge-grid, .metric-list { grid-template-columns: 1fr 1fr; }
}

/* Multi-tenant/auth additions */
.auth-page {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 32px;
  background:
    radial-gradient(circle at 10% 10%, rgba(31, 115, 255, 0.12), transparent 30%),
    linear-gradient(135deg, #f8fbff 0%, #eef5ff 100%);
}
.auth-card {
  width: min(440px, 100%);
  background: rgba(255, 255, 255, 0.92);
  border: 1px solid rgba(14, 35, 74, 0.08);
  border-radius: 28px;
  box-shadow: 0 24px 80px rgba(14, 35, 74, 0.14);
  padding: 32px;
}
.auth-brand { margin-bottom: 28px; }
.auth-card h1 { margin: 0 0 8px; }
.auth-card p { color: var(--muted); margin: 0 0 22px; }
.auth-form { display: grid; gap: 16px; }
.auth-flashes { position: fixed; top: 18px; left: 50%; transform: translateX(-50%); z-index: 99; width: min(520px, calc(100% - 32px)); }
.sidebar-footer.stacked { display: grid; gap: 6px; }
.sidebar-footer.stacked > div { display: flex; align-items: center; gap: 8px; }
.muted-link { color: var(--muted); text-decoration: none; font-size: 0.9rem; }
.muted-link:hover { color: var(--primary); }
.checkbox-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 8px 14px; padding: 10px 0; }
.label-title { display: block; font-size: 0.78rem; font-weight: 700; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); margin-bottom: 4px; }
.pill.danger { background: #fff1f2; color: #be123c; border-color: #fecdd3; }
select:disabled, input:read-only, textarea:read-only { background: #f8fafc; color: #64748b; }