:root {
  color-scheme: dark;
  --bg: #0b0f14;
  --card: #121820;
  --card-subtle: #161f2a;
  --border: #1f2a38;
  --border-strong: #2c3c50;
  --text: #f1f5f9;
  --muted: #8494a7;
  --muted-bright: #cbd5e1;

  /* State colors */
  --red: #ef4444;
  --red-dim: #3b1419;
  --red-glow: rgba(239, 68, 68, 0.5);

  --yellow: #f59e0b;
  --yellow-dim: #382507;
  --yellow-glow: rgba(245, 158, 11, 0.5);

  --green: #10b981;
  --green-dim: #07291e;
  --green-glow: rgba(16, 185, 129, 0.5);

  --cyan: #06b6d4;
  --cyan-soft: rgba(6, 182, 212, 0.12);

  --radius: 12px;
  --radius-sm: 8px;
  --font-ui: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: "Cascadia Mono", "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}

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

html {
  background-color: var(--bg);
  min-width: 320px;
}

body {
  min-height: 100vh;
  color: var(--text);
  background: var(--bg);
  font-family: var(--font-ui);
  font-size: 15px;
  line-height: 1.5;
}

[hidden] {
  display: none !important;
}

.app-shell {
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px 24px 36px;
}

/* ======================================================
   TOPBAR
   ====================================================== */
.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 20px;
}

.brand-block {
  display: flex;
  align-items: center;
  gap: 14px;
}

.traffic-mini-icon {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 6px 5px;
  background: #080c10;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  box-shadow: inset 0 0 6px rgba(0, 0, 0, 0.6);
}

.traffic-mini-icon span {
  width: 8px;
  height: 8px;
  border-radius: 50%;
}

.traffic-mini-icon span:nth-child(1) { background: var(--red); box-shadow: 0 0 6px var(--red); }
.traffic-mini-icon span:nth-child(2) { background: var(--yellow); box-shadow: 0 0 6px var(--yellow); }
.traffic-mini-icon span:nth-child(3) { background: var(--green); box-shadow: 0 0 6px var(--green); }

.eyebrow {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--cyan);
  margin-bottom: 3px;
}

h1 {
  font-size: clamp(1.2rem, 2.2vw, 1.55rem);
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--text);
}

.header-status {
  display: flex;
  align-items: center;
  gap: 16px;
}

/* IP Connect Form */
.ip-config-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  position: relative;
}

.ip-label {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--muted);
  letter-spacing: 0.05em;
  white-space: nowrap;
}

.ip-input-group {
  display: flex;
  align-items: center;
  gap: 6px;
}

.ip-input {
  width: 130px;
  padding: 6px 10px;
  font-family: var(--font-mono);
  font-size: 0.84rem;
  color: var(--text);
  background: var(--card-subtle);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  outline: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.ip-input:focus {
  border-color: var(--cyan);
  box-shadow: 0 0 0 2px rgba(6, 182, 212, 0.2);
}

.ip-input.is-invalid {
  border-color: var(--red) !important;
  box-shadow: 0 0 0 2px rgba(239, 68, 68, 0.25) !important;
}

.btn-connect {
  padding: 6px 14px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.03em;
  color: #0b0f14;
  background: var(--cyan);
  border: 1px solid var(--cyan);
  border-radius: var(--radius-sm);
  cursor: pointer;
  white-space: nowrap;
  transition: background-color 0.15s ease, box-shadow 0.15s ease, transform 0.08s ease;
}

.btn-connect:hover {
  background: #22d3ee;
  border-color: #22d3ee;
  box-shadow: 0 0 10px rgba(6, 182, 212, 0.35);
}

.btn-connect:active {
  transform: scale(0.97);
}

.ip-error-text {
  position: absolute;
  top: calc(100% + 4px);
  left: 0;
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--red);
  white-space: nowrap;
  z-index: 10;
  background: rgba(18, 24, 32, 0.95);
  padding: 2px 8px;
  border-radius: 4px;
  border: 1px solid rgba(239, 68, 68, 0.3);
}

.connection-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: 999px;
  border: 1px solid var(--border-strong);
  background: var(--card);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--muted-bright);
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--yellow);
  box-shadow: 0 0 8px var(--yellow);
}

.connection-badge.is-connecting {
  color: var(--yellow);
  border-color: rgba(245, 158, 11, 0.35);
  background: rgba(245, 158, 11, 0.08);
}
.connection-badge.is-connecting .status-dot {
  background: var(--yellow);
  box-shadow: 0 0 8px var(--yellow);
}

.connection-badge.is-online {
  color: var(--green);
  border-color: rgba(16, 185, 129, 0.35);
  background: rgba(16, 185, 129, 0.08);
}
.connection-badge.is-online .status-dot {
  background: var(--green);
  box-shadow: 0 0 8px var(--green);
}

.connection-badge.is-offline {
  color: var(--red);
  border-color: rgba(239, 68, 68, 0.35);
  background: rgba(239, 68, 68, 0.08);
}
.connection-badge.is-offline .status-dot {
  background: var(--red);
  box-shadow: 0 0 8px var(--red);
}

.header-time {
  border-left: 1px solid var(--border);
  padding-left: 14px;
  display: flex;
  flex-direction: column;
}

.time-label {
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.header-time strong {
  font-family: var(--font-mono);
  font-size: 0.92rem;
  color: var(--muted-bright);
}

/* ======================================================
   ALERTS
   ====================================================== */
.connection-alert,
.priority-alert {
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  margin-bottom: 20px;
}

.connection-alert {
  display: flex;
  align-items: center;
  gap: 12px;
  background: rgba(239, 68, 68, 0.12);
  border: 1px solid rgba(239, 68, 68, 0.35);
  color: #fee2e2;
}

.connection-alert .alert-icon {
  display: grid;
  place-items: center;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--red);
  color: #fff;
  font-weight: 800;
  font-size: 0.85rem;
}

.connection-alert strong {
  display: block;
  font-size: 0.92rem;
}

.connection-alert span {
  font-size: 0.82rem;
  color: #fca5a5;
}

.priority-alert {
  background: rgba(245, 158, 11, 0.12);
  border: 1px solid rgba(245, 158, 11, 0.4);
  color: #fef3c7;
}

.priority-alert strong {
  font-size: 0.95rem;
  color: var(--yellow);
}

.priority-alert p {
  margin-top: 4px;
  font-size: 0.88rem;
  color: #fde68a;
}

/* ======================================================
   MAIN 2-COLUMN LAYOUT
   ====================================================== */
main {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.traffic-columns {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.direction-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 22px;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  transition: border-color 0.2s ease;
}

.direction-header {
  width: 100%;
  margin-bottom: 20px;
}

.direction-tag {
  display: inline-block;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--cyan);
  margin-bottom: 4px;
}

.direction-header h2 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text);
}

/* ======================================================
   TRAFFIC LIGHT BOX
   ====================================================== */
.traffic-light-box {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  margin-bottom: 24px;
}

.traffic-light-housing {
  display: flex;
  flex-direction: row;
  align-items: center;
  justify-content: center;
  gap: 14px;
  padding: 12px 20px;
  background: #080c10;
  border: 2px solid var(--border-strong);
  border-radius: 999px;
  box-shadow: inset 0 3px 8px rgba(0, 0, 0, 0.8), 0 4px 12px rgba(0, 0, 0, 0.4);
}

.light {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  border: 1px solid rgba(255, 255, 255, 0.08);
  transition: background-color 0.15s ease, box-shadow 0.15s ease;
}

.light.red {
  background: var(--red-dim);
}

.light.yellow {
  background: var(--yellow-dim);
}

.light.green {
  background: var(--green-dim);
}

.light.red.is-active {
  background: var(--red);
  box-shadow: 0 0 16px var(--red-glow), 0 0 28px rgba(239, 68, 68, 0.3);
}

.light.yellow.is-active {
  background: var(--yellow);
  box-shadow: 0 0 16px var(--yellow-glow), 0 0 28px rgba(245, 158, 11, 0.3);
}

.light.green.is-active {
  background: var(--green);
  box-shadow: 0 0 16px var(--green-glow), 0 0 28px rgba(16, 185, 129, 0.3);
}

.light-status-text {
  font-family: var(--font-mono);
  font-size: 0.88rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--muted-bright);
}

/* ======================================================
   COUNTDOWN HERO
   ====================================================== */
.countdown-hero {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 100%;
  padding: 20px 14px;
  background: var(--card-subtle);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  margin-bottom: 22px;
}

.countdown-number {
  font-family: var(--font-mono);
  font-size: clamp(3.2rem, 6vw, 4.4rem);
  font-weight: 800;
  line-height: 1;
  color: #ffffff;
  letter-spacing: -0.02em;
}

.countdown-unit {
  font-size: 0.85rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-top: 6px;
  font-weight: 600;
}

/* ======================================================
   DIRECTION DETAILS (4 SENSORS & DENSITY)
   ====================================================== */
.direction-details {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.detail-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 9px 14px;
  background: var(--card-subtle);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

.detail-label {
  font-size: 0.84rem;
  color: var(--muted);
}

.sensor-badge,
.density-badge,
.sensor-count-badge {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--muted-bright);
}

.sensor-badge.is-detected {
  color: var(--yellow);
  background: rgba(245, 158, 11, 0.14);
  border: 1px solid rgba(245, 158, 11, 0.3);
}

.sensor-badge.is-clear {
  color: var(--green);
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid rgba(16, 185, 129, 0.25);
}

.sensor-count-badge {
  font-weight: 600;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.02);
}

.density-badge.density-empty {
  color: var(--green);
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid rgba(16, 185, 129, 0.25);
}

.density-badge.density-low {
  color: var(--yellow);
  background: rgba(245, 158, 11, 0.14);
  border: 1px solid rgba(245, 158, 11, 0.3);
}

.density-badge.density-high {
  color: var(--red);
  background: rgba(239, 68, 68, 0.14);
  border: 1px solid rgba(239, 68, 68, 0.3);
}

/* ======================================================
   SYSTEM SECTION
   ====================================================== */
.system-section,
.events-section {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 22px;
}

.section-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 14px;
  letter-spacing: 0.02em;
}

.system-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}

.system-item {
  padding: 12px 14px;
  background: var(--card-subtle);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-width: 0;
}

.system-label {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 4px;
}

.system-value {
  font-family: var(--font-mono);
  font-size: 0.88rem;
  color: var(--muted-bright);
}

.ip-mono {
  font-family: var(--font-mono);
  color: var(--cyan);
}

.fsm-item .fsm-content {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.fsm-code {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--cyan);
}

.fsm-desc {
  font-size: 0.78rem;
  color: var(--muted-bright);
  white-space: normal;
}

/* State color utility classes */
.state-red { color: var(--red) !important; }
.state-yellow { color: var(--yellow) !important; }
.state-green { color: var(--green) !important; }
.state-cyan { color: var(--cyan) !important; }
.state-orange { color: var(--yellow) !important; }

/* ======================================================
   EVENTS SECTION
   ====================================================== */
.events-header {
  margin-bottom: 12px;
}

.events-table-wrap {
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

.events-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.84rem;
}

.events-table th,
.events-table td {
  padding: 9px 14px;
  border-bottom: 1px solid var(--border);
}

.events-table th {
  background: var(--card-subtle);
  color: var(--muted);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.events-table td {
  color: var(--muted-bright);
}

.events-table td:first-child {
  width: 110px;
  font-family: var(--font-mono);
  color: var(--muted);
  font-size: 0.78rem;
}

.events-table td:nth-child(2) {
  width: 120px;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  font-weight: 700;
  color: var(--cyan);
}

.events-table tr:last-child td {
  border-bottom: none;
}

.events-table tr.event-alert td:nth-child(2) { color: var(--red); }
.events-table tr.event-sensor td:nth-child(2) { color: var(--yellow); }
.events-table tr.event-mode td:nth-child(2) { color: var(--green); }

/* ======================================================
   FOOTER
   ====================================================== */
footer {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding-top: 24px;
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.05em;
}

/* ======================================================
   RESPONSIVE
   ====================================================== */
@media (max-width: 900px) {
  .system-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .app-shell {
    padding: 16px 14px 28px;
  }

  .topbar {
    flex-direction: column;
    align-items: flex-start;
    gap: 14px;
  }

  .header-status {
    width: 100%;
    flex-wrap: wrap;
    justify-content: flex-start;
    gap: 12px;
  }

  .header-ip,
  .header-time {
    padding-left: 10px;
  }

  .traffic-columns {
    grid-template-columns: 1fr;
  }

  .system-grid {
    grid-template-columns: 1fr;
  }

  footer {
    flex-direction: column;
    gap: 4px;
  }
}