:root {
  --bg: #f5f7fb;
  --panel: #ffffff;
  --panel-soft: #eef2f7;
  --text: #101828;
  --muted: #475467;
  --border: #d0d5dd;
  --accent: #1570ef;
  --accent-soft: #dbeafe;
  --danger: #d92d20;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
}

.app-shell {
  min-height: 100vh;
  padding: 12px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.top-bar,
.tool-bar,
.status-bar {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 8px 12px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}

.brand {
  margin: 0;
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: 0.2px;
}

.segmented,
.tf-group,
.placeholder-group {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.segmented-btn,
.tf-btn,
.ghost-btn {
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--panel-soft);
  color: var(--text);
  padding: 6px 10px;
  font-size: 0.88rem;
  cursor: pointer;
}

.segmented-btn.active,
.tf-btn.active {
  background: var(--accent-soft);
  border-color: var(--accent);
  color: #0b4cbf;
}

.ghost-btn[disabled] {
  opacity: 0.55;
  cursor: not-allowed;
}

.chart-panel {
  position: relative;
  flex: 1;
  min-height: 70vh;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
}

.chart-container {
  width: 100%;
  height: 100%;
}

.chart-tooltip {
  position: absolute;
  z-index: 20;
  pointer-events: none;
  top: 10px;
  left: 10px;
  min-width: 220px;
  background: rgba(16, 24, 40, 0.92);
  color: #fff;
  border-radius: 8px;
  padding: 8px 10px;
  font-size: 0.8rem;
  line-height: 1.35;
  box-shadow: 0 6px 18px rgba(16, 24, 40, 0.2);
}

.chart-tooltip.hidden {
  display: none;
}

.no-data-overlay {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  z-index: 15;
  pointer-events: none;
  background: rgba(255, 255, 255, 0.92);
  border: 1px solid var(--border);
  color: var(--muted);
  border-radius: 8px;
  padding: 8px 12px;
  font-size: 0.85rem;
}

.tooltip-tz {
  color: #cbd5e1;
  margin-top: 4px;
}

.status-bar {
  justify-content: space-between;
  font-size: 0.85rem;
  color: var(--muted);
  gap: 10px;
  flex-wrap: wrap;
}

.status-bar .error {
  color: var(--danger);
}

.loading-more {
  color: #0b4cbf;
  font-weight: 600;
}

.hidden {
  display: none !important;
}

@media (max-width: 920px) {
  .top-bar,
  .tool-bar {
    flex-direction: column;
    align-items: flex-start;
  }

  .chart-panel {
    min-height: 64vh;
  }
}