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

html,
body {
  margin: 0;
  height: 100%;
  overflow: hidden;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  font-size: 14px;
  color: #e8eaed;
  background: #0d1117;
}

.app {
  display: flex;
  height: 100vh;
  width: 100vw;
}

.viewport {
  flex: 1;
  position: relative;
  min-width: 0;
  background: #0a1628;
}

#horizon-canvas {
  display: block;
  width: 100%;
  height: 100%;
}

.hud {
  position: absolute;
  top: 16px;
  left: 16px;
  pointer-events: none;
  font-family: "SF Mono", "Cascadia Code", "Consolas", monospace;
  font-size: 13px;
  line-height: 1.6;
  color: #c9d1d9;
}

.hud-badge {
  display: inline-block;
  margin-top: 8px;
  padding: 4px 10px;
  border: 1px solid;
  border-radius: 3px;
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.hud-badge--likely {
  border-color: #3fb950;
  color: #3fb950;
}

.hud-badge--unlikely {
  border-color: #8b949e;
  color: #8b949e;
}

.hud-badge--partial {
  border-color: #d29922;
  color: #d29922;
}

.sidebar {
  width: 360px;
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  border-left: 1px solid #30363d;
  background: #161b22;
  overflow: hidden;
}

.sidebar-header {
  padding: 16px 16px 12px;
  border-bottom: 1px solid #30363d;
}

.tool-nav {
  margin: 0 0 10px;
  font-size: 12px;
}

.tool-nav a {
  color: #58a6ff;
  text-decoration: none;
}

.tool-nav a:hover,
.tool-nav a:focus-visible {
  color: #79c0ff;
  text-decoration: underline;
}

.sidebar-header h1 {
  margin: 0;
  font-size: 16px;
  font-weight: 600;
  color: #f0f6fc;
}

.subtitle {
  margin: 4px 0 0;
  font-size: 12px;
  color: #8b949e;
}

.controls {
  padding: 16px;
  border-bottom: 1px solid #30363d;
}

.control-label {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 6px;
  margin-top: 14px;
  font-size: 12px;
  font-weight: 500;
  color: #c9d1d9;
}

.control-label:first-of-type {
  margin-top: 0;
}

.control-value {
  font-family: "SF Mono", "Cascadia Code", "Consolas", monospace;
  font-size: 12px;
  color: #58a6ff;
}

.control-select optgroup {
  font-style: normal;
  color: #8b949e;
}

.control-select option {
  color: #e8eaed;
  background: #0d1117;
}

.control-select {
  width: 100%;
  padding: 8px 10px;
  border: 1px solid #30363d;
  border-radius: 4px;
  background: #0d1117;
  color: #e8eaed;
  font-size: 13px;
}

.control-hint {
  margin: 6px 0 0;
  font-size: 11px;
  color: #8b949e;
  line-height: 1.4;
}

.control-slider {
  width: 100%;
  accent-color: #58a6ff;
}

.control-check {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 16px;
  font-size: 12px;
  color: #c9d1d9;
  cursor: pointer;
}

.diagram-section {
  padding: 12px 16px;
  border-bottom: 1px solid #30363d;
}

.section-title {
  margin: 0 0 8px;
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: #8b949e;
}

#cross-section-canvas {
  display: block;
  width: 100%;
  height: 180px;
  background: #0d1117;
  border: 1px solid #30363d;
  border-radius: 4px;
}

.math-section {
  flex: 1;
  overflow-y: auto;
  padding: 12px 16px 24px;
}

.math-block {
  margin-bottom: 14px;
  padding: 10px 12px;
  border: 1px solid #30363d;
  border-radius: 4px;
  background: #0d1117;
}

.math-block-title {
  margin: 0 0 6px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #8b949e;
}

.math-formula {
  margin: 0 0 6px;
  font-family: "SF Mono", "Cascadia Code", "Consolas", monospace;
  font-size: 13px;
  color: #e6edf3;
}

.math-result {
  margin: 0;
  font-family: "SF Mono", "Cascadia Code", "Consolas", monospace;
  font-size: 12px;
  color: #58a6ff;
}

.math-note {
  margin: 16px 0 0;
  padding-top: 12px;
  border-top: 1px solid #30363d;
  font-size: 11px;
  line-height: 1.5;
  color: #8b949e;
}

.math-note a {
  color: #58a6ff;
}

@media (max-width: 900px) {
  .app {
    flex-direction: column;
  }

  .viewport {
    height: 45vh;
    flex: none;
  }

  .sidebar {
    width: 100%;
    flex: 1;
    border-left: none;
    border-top: 1px solid #30363d;
  }
}