:root {
  color-scheme: dark;
  --page: #081019;
  --page-soft: #0d1722;
  --panel: #111d29;
  --panel-strong: #172534;
  --border: #27394a;
  --border-soft: rgba(255, 255, 255, 0.07);
  --text: #f4f7fa;
  --muted: #97a7b7;
  --accent: #5da9ff;
  --accent-strong: #2f8cf4;
  --good: #4bd083;
  --warning: #efb951;
  --bad: #f06d6d;
  --neutral: #a9b7c5;
  --shadow: 0 18px 45px rgba(0, 0, 0, 0.24);
  --radius: 16px;
}

* { box-sizing: border-box; }
html { min-height: 100%; background: var(--page); }
body {
  min-height: 100vh;
  margin: 0;
  color: var(--text);
  background:
    radial-gradient(circle at 85% 0%, rgba(57, 117, 184, 0.17), transparent 30rem),
    linear-gradient(180deg, #0a131d 0%, var(--page) 35%, #070d14 100%);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}
button, input, select { font: inherit; }
a { color: inherit; }
h1, h2, p { margin-top: 0; }
h1 { margin-bottom: 8px; font-size: clamp(2rem, 4vw, 3.3rem); letter-spacing: -0.045em; line-height: 1.02; }
h2 { margin: 0; font-size: 1.08rem; letter-spacing: -0.015em; }
small { color: var(--muted); }
.muted { color: var(--muted); }
.eyebrow { margin-bottom: 8px; color: #77b9ff; font-size: 0.72rem; font-weight: 800; letter-spacing: 0.13em; text-transform: uppercase; }

.topbar { position: sticky; top: 0; z-index: 50; border-bottom: 1px solid rgba(255, 255, 255, 0.06); background: rgba(8, 16, 25, 0.88); backdrop-filter: blur(18px); }
.topbar-inner { width: min(1440px, calc(100% - 32px)); min-height: 72px; margin: 0 auto; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand { display: inline-flex; align-items: center; gap: 12px; text-decoration: none; }
.brand > span:last-child { display: grid; gap: 2px; }
.brand strong { font-size: 0.98rem; }
.brand small { font-size: 0.75rem; }
.brand-mark { display: grid; place-items: center; width: 76px; height: 76px; border: 1px solid rgba(93, 169, 255, 0.48); border-radius: 22px; background: linear-gradient(145deg, rgba(93, 169, 255, 0.25), rgba(47, 140, 244, 0.08)); color: #d9ebff; font-size: 1.3rem; font-weight: 900; letter-spacing: -0.05em; box-shadow: inset 0 1px 0 rgba(255,255,255,.1); }
.brand-mark-small { width: 42px; height: 42px; border-radius: 12px; font-size: 0.8rem; }
.top-actions { display: flex; align-items: center; gap: 9px; }
.user-chip { display: grid; gap: 1px; padding: 7px 11px; border: 1px solid var(--border); border-radius: 10px; background: rgba(255,255,255,.025); }
.user-chip span { font-size: 0.82rem; font-weight: 750; }
.user-chip small { font-size: 0.67rem; }

.page-shell { width: min(1440px, calc(100% - 32px)); margin: 0 auto; padding: 34px 0 54px; }
.page-heading { display: flex; align-items: flex-end; justify-content: space-between; gap: 24px; margin-bottom: 24px; }
.page-heading p { margin-bottom: 0; }
.last-update { color: var(--muted); font-size: 0.78rem; white-space: nowrap; }

.health-banner { display: flex; align-items: center; justify-content: space-between; gap: 18px; margin-bottom: 18px; padding: 18px 20px; border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow); }
.health-good { background: linear-gradient(105deg, rgba(75, 208, 131, 0.1), rgba(17, 29, 41, 0.92) 42%); }
.health-attention { background: linear-gradient(105deg, rgba(239, 185, 81, 0.12), rgba(17, 29, 41, 0.92) 42%); }
.health-summary { display: flex; align-items: center; gap: 14px; }
.health-summary > div { display: grid; gap: 4px; }
.health-summary strong { font-size: 1.05rem; }
.health-summary span:last-child { color: var(--muted); font-size: 0.8rem; }

.status-dot { display: inline-block; width: 10px; height: 10px; flex: 0 0 10px; border-radius: 50%; box-shadow: 0 0 0 5px rgba(255,255,255,.035); }
.status-dot-large { width: 16px; height: 16px; flex-basis: 16px; }
.status-good { background: var(--good); }
.status-warning { background: var(--warning); }
.status-bad { background: var(--bad); }

.badge { display: inline-flex; align-items: center; justify-content: center; min-height: 25px; padding: 4px 9px; border-radius: 999px; font-size: 0.68rem; font-weight: 850; letter-spacing: 0.045em; text-transform: uppercase; white-space: nowrap; }
.badge-info { color: #add7ff; background: rgba(93, 169, 255, 0.14); }
.badge-warning { color: #f3cb79; background: rgba(239, 185, 81, 0.14); }
.badge-danger { color: #ffaaaa; background: rgba(240, 109, 109, 0.15); }
.badge-neutral { color: #c0ccd7; background: rgba(169, 183, 197, 0.1); }

.summary-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; margin-bottom: 18px; }
.summary-card { min-width: 0; padding: 17px 18px; border: 1px solid var(--border); border-radius: 14px; background: linear-gradient(145deg, rgba(23, 37, 52, .95), rgba(17, 29, 41, .94)); box-shadow: var(--shadow); }
.summary-card-top { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 15px; color: var(--muted); font-size: 0.72rem; font-weight: 750; letter-spacing: .06em; text-transform: uppercase; }
.summary-card strong { display: block; margin-bottom: 5px; font-size: 1.35rem; letter-spacing: -.02em; }
.summary-card small { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: .74rem; }

.dashboard-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.panel { min-width: 0; padding: 20px; border: 1px solid var(--border); border-radius: var(--radius); background: linear-gradient(145deg, rgba(23, 37, 52, .92), rgba(17, 29, 41, .94)); box-shadow: var(--shadow); }
.panel-span-2 { grid-column: span 2; }
.panel-span-3 { grid-column: 1 / -1; }
.panel-header { display: flex; align-items: flex-start; justify-content: space-between; gap: 18px; margin-bottom: 18px; }
.panel-note { margin: 16px 0 0; color: var(--muted); font-size: .73rem; line-height: 1.55; }

.device-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; }
.device-tile { min-width: 0; display: grid; grid-template-columns: 38px minmax(0, 1fr) auto; align-items: center; gap: 11px; padding: 13px; border: 1px solid var(--border-soft); border-radius: 12px; background: rgba(255,255,255,.022); }
.device-icon { display: grid; place-items: center; width: 38px; height: 38px; border-radius: 11px; background: rgba(93,169,255,.12); color: #b9dbff; font-weight: 900; }
.device-tile > div:nth-child(2) { min-width: 0; display: grid; gap: 3px; }
.device-tile strong { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: .88rem; }
.device-tile span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: var(--muted); font-size: .69rem; }
.device-state { font-size: .72rem !important; font-weight: 800; }
.state-good { color: var(--good) !important; }
.state-warning { color: var(--warning) !important; }
.state-bad { color: var(--bad) !important; }
.state-muted { color: var(--muted) !important; }

.data-list { margin: 0; }
.data-list > div, .service-list > div { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 10px 0; border-bottom: 1px solid var(--border-soft); }
.data-list > div:last-child, .service-list > div:last-child { border-bottom: 0; }
.data-list dt, .service-list span { color: var(--muted); font-size: .78rem; }
.data-list dd { margin: 0; font-size: .82rem; font-weight: 760; }
.service-list strong { font-size: .75rem; }
.resource-row { display: grid; grid-template-columns: repeat(3, 1fr); gap: 9px; margin-top: 15px; }
.resource-row > div { display: grid; gap: 4px; padding: 11px; border: 1px solid var(--border-soft); border-radius: 10px; background: rgba(255,255,255,.02); }
.resource-row span { color: var(--muted); font-size: .68rem; }
.resource-row strong { font-size: .95rem; }

.metric-grid { display: grid; grid-template-columns: repeat(4, minmax(0,1fr)); gap: 10px; margin-bottom: 18px; }
.metric-grid > div { display: grid; gap: 6px; padding: 13px; border: 1px solid var(--border-soft); border-radius: 11px; background: rgba(255,255,255,.02); }
.metric-grid span { color: var(--muted); font-size: .67rem; font-weight: 750; letter-spacing: .05em; text-transform: uppercase; }
.metric-grid strong { font-size: 1.18rem; }
.speed-chart { min-height: 240px; border: 1px solid var(--border-soft); border-radius: 12px; background: rgba(4, 10, 16, .25); overflow: hidden; }
.speed-chart svg { width: 100%; height: 240px; display: block; }
.chart-grid-line { stroke: rgba(255,255,255,.07); stroke-width: 1; }
.chart-download { fill: none; stroke: #5da9ff; stroke-width: 3; vector-effect: non-scaling-stroke; }
.chart-upload { fill: none; stroke: #4bd083; stroke-width: 3; vector-effect: non-scaling-stroke; }
.chart-latency { fill: none; stroke: #efb951; stroke-width: 2; stroke-dasharray: 7 5; vector-effect: non-scaling-stroke; }
.chart-point-download { fill: #5da9ff; }
.chart-point-upload { fill: #4bd083; }
.chart-empty { display: grid; place-items: center; min-height: 240px; color: var(--muted); font-size: .8rem; }
.chart-legend { display: flex; align-items: center; gap: 16px; margin-top: 11px; color: var(--muted); font-size: .7rem; }
.chart-legend span::before { content: ""; display: inline-block; width: 14px; height: 3px; margin-right: 6px; border-radius: 3px; vertical-align: middle; }
.legend-download::before { background: #5da9ff; }
.legend-upload::before { background: #4bd083; }
.legend-latency::before { background: #efb951; }
.chart-legend small { margin-left: auto; }

.control-stack { display: grid; gap: 9px; }
.button { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 40px; padding: 9px 13px; border: 1px solid #405468; border-radius: 10px; color: var(--text); background: #223142; text-decoration: none; cursor: pointer; transition: background .15s ease, border-color .15s ease, transform .15s ease; }
.button:hover { background: #2a3c50; border-color: #526c84; }
.button:active { transform: translateY(1px); }
.button:disabled { opacity: .52; cursor: wait; }
.button-primary { border-color: #4c9bf2; background: #267fdc; }
.button-primary:hover { background: #328deb; }
.button-secondary { border-color: rgba(93,169,255,.48); background: rgba(93,169,255,.12); }
.button-warning { border-color: rgba(239,185,81,.55); background: rgba(239,185,81,.12); }
.button-danger { border-color: rgba(240,109,109,.52); background: rgba(240,109,109,.1); }
.button-quiet { border-color: var(--border); background: rgba(255,255,255,.025); }
.button-compact { min-height: 34px; padding: 7px 10px; font-size: .75rem; }
.button-full { width: 100%; }
.button-control { justify-content: space-between; text-align: left; }
.button-control span, .button-danger span { font-weight: 760; }
.button-control small, .button-danger small { margin-left: auto; font-size: .64rem; }
.maintenance-control { display: flex; align-items: center; justify-content: space-between; gap: 15px; margin-top: 14px; padding-top: 14px; border-top: 1px solid var(--border-soft); }
.maintenance-control > div { display: grid; gap: 3px; }
.maintenance-control span { color: var(--muted); font-size: .7rem; }

.event-list { display: grid; }
.event-row { display: grid; grid-template-columns: 170px 84px minmax(0, 1fr); align-items: start; gap: 14px; padding: 12px 0; border-bottom: 1px solid var(--border-soft); }
.event-row:last-child { border-bottom: 0; }
.event-row time { color: var(--muted); font-size: .72rem; }
.event-row > div { display: grid; gap: 4px; }
.event-row strong { font-size: .82rem; }
.event-row div span { color: var(--muted); font-size: .72rem; line-height: 1.45; }
.empty-state { padding: 28px; color: var(--muted); text-align: center; }

.toast { position: fixed; right: 20px; bottom: 20px; z-index: 100; max-width: min(440px, calc(100% - 40px)); padding: 14px 16px; border: 1px solid var(--border); border-radius: 11px; background: #1a2938; color: var(--text); box-shadow: var(--shadow); opacity: 0; transform: translateY(14px); pointer-events: none; transition: .2s ease; }
.toast.visible { opacity: 1; transform: translateY(0); }
.toast.error { border-color: rgba(240,109,109,.7); }

.auth-page { display: grid; place-items: center; padding: 22px; }
.auth-shell { width: min(430px, 100%); }
.auth-card { padding: 30px; border: 1px solid var(--border); border-radius: 22px; background: linear-gradient(145deg, rgba(23, 37, 52, .98), rgba(13, 23, 34, .98)); box-shadow: var(--shadow); }
.auth-card .brand-mark { margin-bottom: 26px; }
.auth-card h1 { font-size: 2.2rem; }
.auth-form, .stacked-form { display: grid; gap: 15px; margin-top: 24px; }
.auth-form label, .stacked-form label { display: grid; gap: 7px; }
.auth-form label > span, .stacked-form label > span { color: #dce5ed; font-size: .76rem; font-weight: 720; }
input, select { width: 100%; min-height: 43px; padding: 9px 11px; border: 1px solid #34495e; border-radius: 9px; outline: none; background: #0d1823; color: var(--text); }
input:focus, select:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(93,169,255,.12); }
.auth-note { margin: 20px 0 0; color: var(--muted); font-size: .69rem; line-height: 1.5; }
.alert { margin-top: 18px; padding: 11px 12px; border-radius: 9px; font-size: .78rem; }
.alert-error { border: 1px solid rgba(240,109,109,.45); background: rgba(240,109,109,.1); color: #ffb4b4; }

.admin-grid { display: grid; grid-template-columns: minmax(280px, .8fr) minmax(0, 2fr); gap: 16px; }
.user-list { display: grid; }
.user-row { display: grid; grid-template-columns: minmax(0,1fr) auto auto; align-items: center; gap: 14px; padding: 13px 0; border-bottom: 1px solid var(--border-soft); }
.user-row:last-child { border-bottom: 0; }
.user-row > div:first-child { min-width: 0; display: grid; gap: 4px; }
.user-row > div:first-child span { color: var(--muted); font-size: .7rem; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.row-actions { display: flex; gap: 8px; }

@media (max-width: 1100px) {
  .summary-grid { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .dashboard-grid { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .panel-span-3 { grid-column: 1 / -1; }
  .admin-grid { grid-template-columns: 1fr; }
  .admin-grid .panel-span-2 { grid-column: 1; }
}

@media (max-width: 760px) {
  .topbar-inner, .page-shell { width: min(100% - 20px, 1440px); }
  .topbar-inner { min-height: 64px; }
  .top-actions .button-quiet:not(#logout-button), .top-actions .user-chip { display: none; }
  .page-shell { padding-top: 24px; }
  .page-heading, .health-banner { align-items: flex-start; flex-direction: column; }
  .summary-grid, .dashboard-grid { grid-template-columns: 1fr; }
  .panel-span-2, .panel-span-3 { grid-column: 1; }
  .device-grid { grid-template-columns: 1fr; }
  .metric-grid { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .event-row { grid-template-columns: 1fr; gap: 7px; }
  .event-row .badge { justify-self: start; }
  .chart-legend { flex-wrap: wrap; }
  .chart-legend small { width: 100%; margin-left: 0; }
  .user-row { grid-template-columns: 1fr auto; }
  .row-actions { grid-column: 1 / -1; }
}

@media (max-width: 470px) {
  .metric-grid, .summary-grid { grid-template-columns: 1fr; }
  .panel { padding: 16px; }
  .health-banner { padding: 16px; }
  .button-control, .button-danger { align-items: flex-start; flex-direction: column; }
  .button-control small, .button-danger small { margin-left: 0; }
  .resource-row { grid-template-columns: 1fr; }
}