:root {
  --bg-primary: #0a0e17;
  --bg-card: #141c2e;
  --bg-card-hover: #1a253c;
  --border-color: #24324d;
  --border-glow: rgba(56, 189, 248, 0.3);
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --accent-cyan: #38bdf8;
  --accent-cyan-dark: #0284c7;
  --accent-blue: #3b82f6;
  --accent-green: #10b981;
  --accent-purple: #8b5cf6;
  --accent-amber: #f59e0b;
  --accent-red: #ef4444;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-family);
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--accent-cyan);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: #7dd3fc;
}

/* --- Header & Navigation --- */
.site-header {
  border-bottom: 1px solid var(--border-color);
  background: rgba(10, 14, 23, 0.85);
  backdrop-filter: blur(8px);
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 14px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text-primary);
}

.brand-logo {
  height: 34px;
  width: auto;
}

.nav-links {
  display: flex;
  gap: 20px;
  align-items: center;
  list-style: none;
}

.nav-links a {
  color: var(--text-secondary);
  font-size: 0.95rem;
  font-weight: 500;
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  transition: all 0.2s ease;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text-primary);
  background: rgba(56, 189, 248, 0.1);
}

/* --- Main Layout --- */
.main-content {
  flex: 1;
  max-width: 1100px;
  margin: 0 auto;
  width: 100%;
  padding: 32px 20px;
  display: flex;
  flex-direction: column;
  gap: 28px;
}

/* --- Hero Banner & Node Badge --- */
.node-hero {
  text-align: center;
  margin-bottom: 8px;
}

.node-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid rgba(16, 185, 129, 0.3);
  color: #34d399;
  font-size: 0.825rem;
  font-weight: 600;
  padding: 5px 14px;
  border-radius: 9999px;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #10b981;
  box-shadow: 0 0 8px #10b981;
  animation: pulse-glow 2s infinite ease-in-out;
}

@keyframes pulse-glow {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.85); }
}

.node-title {
  font-size: 2rem;
  font-weight: 700;
  margin-top: 12px;
  color: var(--text-primary);
  letter-spacing: -0.5px;
}

.node-subtitle {
  color: var(--text-secondary);
  font-size: 1rem;
  margin-top: 6px;
}

/* --- Speedtest Center Stage (Gauge & Button) --- */
.speedtest-panel {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 40px 24px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.gauge-container {
  width: 280px;
  height: 280px;
  margin: 0 auto 24px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.gauge-svg {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}

.gauge-bg-circle {
  fill: none;
  stroke: #1e293b;
  stroke-width: 14;
}

.gauge-progress-circle {
  fill: none;
  stroke: url(#gauge-gradient);
  stroke-width: 14;
  stroke-linecap: round;
  stroke-dasharray: 754;
  stroke-dashoffset: 754;
  transition: stroke-dashoffset 0.15s ease-out;
}

.gauge-readout {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  pointer-events: none;
}

.gauge-value {
  font-size: 3.5rem;
  font-weight: 800;
  color: var(--text-primary);
  line-height: 1;
  font-variant-numeric: tabular-nums;
  letter-spacing: -1px;
}

.gauge-unit {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--accent-cyan);
  margin-top: 4px;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.gauge-phase {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-muted);
  margin-top: 4px;
  text-transform: uppercase;
}

/* Action Button */
.btn-control {
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-cyan-dark));
  color: #04101e;
  border: none;
  font-family: inherit;
  font-size: 1.1rem;
  font-weight: 700;
  padding: 14px 42px;
  border-radius: 9999px;
  cursor: pointer;
  transition: all 0.25s ease;
  box-shadow: 0 4px 20px rgba(56, 189, 248, 0.35);
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.btn-control:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 6px 26px rgba(56, 189, 248, 0.5);
}

.btn-control:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

.btn-control.btn-abort {
  background: linear-gradient(135deg, var(--accent-red), #b91c1c);
  color: #ffffff;
  box-shadow: 0 4px 20px rgba(239, 68, 68, 0.35);
}

/* --- Metrics Grid --- */
.metrics-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.metric-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 20px;
  text-align: center;
  transition: all 0.2s ease;
  position: relative;
}

.metric-card:hover {
  background: var(--bg-card-hover);
  border-color: rgba(56, 189, 248, 0.4);
}

.metric-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 20%;
  right: 20%;
  height: 2px;
  background: var(--accent-cyan);
  border-radius: 2px;
  opacity: 0.6;
}

.metric-card.card-ping::before { background: var(--accent-purple); }
.metric-card.card-jitter::before { background: var(--accent-amber); }
.metric-card.card-download::before { background: var(--accent-cyan); }
.metric-card.card-upload::before { background: var(--accent-green); }

.metric-header {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 8px;
}

.metric-number {
  font-size: 2rem;
  font-weight: 700;
  color: var(--text-primary);
  font-variant-numeric: tabular-nums;
  line-height: 1.1;
}

.metric-unit {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 500;
  margin-top: 4px;
}

/* --- Client & Node Info Section --- */
.info-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.info-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 20px;
}

.info-card-title {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.info-row {
  display: flex;
  justify-content: space-between;
  padding: 8px 0;
  border-bottom: 1px solid rgba(36, 50, 77, 0.5);
  font-size: 0.925rem;
}

.info-row:last-child {
  border-bottom: none;
}

.info-label {
  color: var(--text-muted);
}

.info-val {
  color: var(--text-primary);
  font-weight: 500;
  font-variant-numeric: tabular-nums;
}

/* --- Status Page Specific Styles --- */
.status-hero {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
}

.status-hero-icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 16px;
  border-radius: 50%;
  background: rgba(16, 185, 129, 0.15);
  border: 2px solid #10b981;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #10b981;
}

.status-hero-title {
  font-size: 1.85rem;
  font-weight: 700;
  color: var(--text-primary);
}

.status-hero-desc {
  color: var(--text-secondary);
  max-width: 600px;
  margin: 8px auto 0;
  font-size: 0.975rem;
}

.telemetry-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.telemetry-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 20px;
}

.telemetry-title {
  color: var(--text-muted);
  font-size: 0.825rem;
  text-transform: uppercase;
  font-weight: 600;
  letter-spacing: 0.5px;
}

.telemetry-value {
  color: var(--text-primary);
  font-size: 1.35rem;
  font-weight: 700;
  margin: 6px 0;
}

.telemetry-sub {
  color: #34d399;
  font-size: 0.825rem;
  font-weight: 500;
}

/* --- Portal Page Specific Styles --- */
.portal-container {
  max-width: 460px;
  margin: 40px auto;
  width: 100%;
}

.portal-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 36px 30px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
}

.portal-icon {
  width: 52px;
  height: 52px;
  margin: 0 auto 18px;
  border-radius: 12px;
  background: rgba(56, 189, 248, 0.12);
  border: 1px solid rgba(56, 189, 248, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
}

.portal-title {
  text-align: center;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
}

.portal-desc {
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.875rem;
  margin: 8px 0 24px;
}

.form-group {
  margin-bottom: 20px;
}

.form-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 8px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.form-input {
  width: 100%;
  background: #090d16;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  font-size: 1rem;
  color: var(--text-primary);
  font-family: inherit;
  transition: all 0.2s ease;
}

.form-input:focus {
  outline: none;
  border-color: var(--accent-cyan);
  box-shadow: 0 0 0 3px rgba(56, 189, 248, 0.18);
}

.btn-portal {
  width: 100%;
  padding: 13px;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-cyan-dark));
  color: #04101e;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.btn-portal:hover:not(:disabled) {
  opacity: 0.95;
  box-shadow: 0 4px 16px rgba(56, 189, 248, 0.3);
}

.btn-portal:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.error-banner {
  background: rgba(239, 68, 68, 0.12);
  border: 1px solid rgba(239, 68, 68, 0.3);
  color: #fca5a5;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  margin-bottom: 20px;
  display: none;
  align-items: center;
  gap: 8px;
}

.error-banner.active {
  display: flex;
}

.spinner {
  width: 18px;
  height: 18px;
  border: 2px solid rgba(4, 16, 30, 0.3);
  border-radius: 50%;
  border-top-color: #04101e;
  animation: spin 0.8s linear infinite;
  display: none;
}

.spinner.active {
  display: inline-block;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* --- Footer --- */
.site-footer {
  border-top: 1px solid var(--border-color);
  background: var(--bg-primary);
  padding: 24px 20px;
  margin-top: auto;
}

.footer-container {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.footer-left {
  display: flex;
  gap: 16px;
  align-items: center;
}

.footer-link {
  color: var(--text-muted);
  font-size: 0.8rem;
  transition: color 0.2s;
}

.footer-link:hover {
  color: var(--text-secondary);
}

/* --- Media Queries --- */
@media (max-width: 768px) {
  .metrics-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .telemetry-grid {
    grid-template-columns: 1fr;
  }
  .info-section {
    grid-template-columns: 1fr;
  }
  .node-title {
    font-size: 1.5rem;
  }
  .gauge-container {
    width: 220px;
    height: 220px;
  }
  .gauge-value {
    font-size: 2.75rem;
  }
  .footer-container {
    flex-direction: column;
    gap: 12px;
    text-align: center;
  }
}