@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Sans:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500;600;700&display=swap');

:root {
  --canvas-bg: #FAF9F7;
  --surface-panel: #FFFFFF;
  --surface-well: #F1EFEA;
  --surface-bezel: #EAE6DF;
  --slate-primary: #1A202C;
  --border-hairline: #D8D2C7;
  --border-contrast: #8C8273;
  --border-focus: #1A202C;

  --text-primary: #191C1E;
  --text-secondary: #4A5056;
  --text-tertiary: #60676F;
  --text-inverse: #FFFFFF;

  --emerald-fg: #065F46;
  --emerald-bg: #ECFDF5;
  --emerald-border: #A7F3D0;

  --amber-fg: #92400E;
  --amber-bg: #FFFBEB;
  --amber-border: #FDE68A;

  --coral-fg: #9A3412;
  --coral-bg: #FFF7ED;
  --coral-border: #FED7AA;

  --cyan-fg: #0E7490;
  --cyan-bg: #ECFEFF;
  --cyan-border: #A5F3FC;

  --font-sans: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

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

html, body {
  background-color: var(--canvas-bg);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 14px;
  line-height: 1.45;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

/* Accessibility: WCAG focus indicator */
:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 2px;
}

/* Typography Roles */
.text-label-caps {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-secondary);
}

.text-metric-lg {
  font-family: var(--font-mono);
  font-size: 32px;
  font-weight: 700;
  line-height: 1.15;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

.text-unit-sub {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  color: var(--text-secondary);
}

/* Base Panel / DIN-Rail Enclosure */
.instrument-card {
  background: var(--surface-panel);
  border: 1px solid var(--border-hairline);
  border-radius: 4px;
  display: flex;
  flex-direction: column;
}

.instrument-card-header {
  height: 38px;
  padding: 0 12px;
  border-bottom: 1px solid var(--border-hairline);
  background: var(--surface-bezel);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.instrument-card-body {
  padding: 14px;
}

/* Recessed Telemetry Well */
.recessed-well {
  background: var(--surface-well);
  border: 1px solid var(--border-hairline);
  border-radius: 2px;
  padding: 10px 12px;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  border-radius: 3px;
  cursor: pointer;
  padding: 6px 14px;
  min-height: 38px;
  min-width: 44px;
  text-decoration: none;
  transition: transform 0.05s ease, background-color 0.1s ease;
  user-select: none;
}

.btn:active {
  transform: translateY(1px);
}

.btn-primary {
  background: var(--slate-primary);
  color: var(--text-inverse);
  border: 1px solid var(--slate-primary);
}

.btn-primary:hover {
  background: #2D3748;
}

.btn-secondary {
  background: var(--surface-panel);
  color: var(--text-primary);
  border: 1px solid var(--border-contrast);
}

.btn-secondary:hover {
  background: var(--surface-well);
}

.btn-danger {
  background: var(--coral-bg);
  color: var(--coral-fg);
  border: 1px solid var(--coral-border);
}

/* Form Inputs */
.input-field {
  font-family: var(--font-mono);
  font-size: 14px;
  background: var(--surface-panel);
  border: 1px solid var(--border-contrast);
  border-radius: 2px;
  padding: 8px 10px;
  color: var(--text-primary);
  width: 100%;
  min-height: 42px;
}

.input-field:focus {
  border-color: var(--border-focus);
}

/* Status Indicator Dots */
.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 0;
  display: inline-block;
}

.status-dot.nominal { background: var(--emerald-fg); }
.status-dot.warning { background: var(--amber-fg); }
.status-dot.alert   { background: var(--coral-fg); }
.status-dot.offline { background: var(--text-tertiary); }

/* Badges */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  border-radius: 2px;
  border: 1px solid var(--border-hairline);
}

.badge-nominal {
  background: var(--emerald-bg);
  color: var(--emerald-fg);
  border-color: var(--emerald-border);
}

.badge-warning {
  background: var(--amber-bg);
  color: var(--amber-fg);
  border-color: var(--amber-border);
}

.badge-alert {
  background: var(--coral-bg);
  color: var(--coral-fg);
  border-color: var(--coral-border);
}

/* Discrete Segmented Bar Gauge */
.segment-meter {
  display: flex;
  gap: 3px;
  width: 100%;
  height: 10px;
  margin-top: 8px;
}

.segment-tick {
  flex: 1;
  background: var(--border-hairline);
  height: 100%;
}

.segment-tick.active-cyan    { background: var(--cyan-fg); }
.segment-tick.active-emerald { background: var(--emerald-fg); }
.segment-tick.active-amber   { background: var(--amber-fg); }
.segment-tick.active-coral   { background: var(--coral-fg); }

/* Layout Structure */
.app-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: var(--surface-panel);
  border-bottom: 1px solid var(--border-hairline);
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
}

.sub-header-strip {
  background: var(--surface-bezel);
  border-bottom: 1px solid var(--border-hairline);
  padding: 8px 16px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.main-container {
  max-width: 1440px;
  margin: 0 auto;
  padding: 16px;
}

.telemetry-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-bottom: 16px;
}

.chart-section {
  background: var(--surface-panel);
  border: 1px solid var(--border-hairline);
  border-radius: 4px;
  padding: 16px;
  margin-bottom: 16px;
}

.history-section {
  background: var(--surface-panel);
  border: 1px solid var(--border-hairline);
  border-radius: 4px;
  overflow: hidden;
}

/* Monospace Telemetry Table */
.data-table-container {
  overflow-x: auto;
  max-height: 420px;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-mono);
  font-size: 12px;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.data-table th {
  background: var(--surface-bezel);
  color: var(--text-secondary);
  font-weight: 700;
  text-align: left;
  padding: 8px 12px;
  border-bottom: 1px solid var(--border-hairline);
  position: sticky;
  top: 0;
  z-index: 2;
}

.data-table td {
  padding: 7px 12px;
  border-bottom: 1px solid var(--border-hairline);
  color: var(--text-primary);
}

.data-table tr:nth-child(even) {
  background: var(--surface-well);
}

/* Modal / Lock Overlay */
.lock-overlay {
  position: fixed;
  inset: 0;
  background: rgba(26, 32, 44, 0.88);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  padding: 16px;
}

.lock-card {
  background: var(--surface-panel);
  border: 2px solid var(--border-focus);
  border-radius: 4px;
  width: 100%;
  max-width: 380px;
  padding: 24px;
  box-shadow: none;
}

.keypad-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin-top: 14px;
}

.keypad-btn {
  height: 52px;
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 700;
  background: var(--surface-well);
  border: 1px solid var(--border-contrast);
  color: var(--text-primary);
  border-radius: 3px;
  cursor: pointer;
}

.keypad-btn:active {
  background: var(--surface-bezel);
  transform: translateY(1px);
}

/* Responsive Breakpoints */
@media (max-width: 1100px) {
  .telemetry-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 680px) {
  .telemetry-grid {
    grid-template-columns: 1fr;
  }
  .app-header {
    height: auto;
    padding: 10px 12px;
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }
  .sub-header-strip {
    flex-direction: column;
    align-items: flex-start;
  }
  .text-metric-lg {
    font-size: 26px;
  }
  .main-container {
    padding: 10px;
  }
}