:root {
  color-scheme: dark;
  font-family: "Inter", "Segoe UI", Arial, sans-serif;
  font-size: 16px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: radial-gradient(circle at 20% 20%, #1c2331, #060608);
  color: #f5f7ff;
  overflow: hidden;
}

#canvas-container {
  position: fixed;
  inset: 0;
  z-index: 0;
}

canvas {
  display: block;
}

.hud {
  position: fixed;
  top: 1.5rem;
  left: 1.5rem;
  right: auto;
  bottom: auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: min(420px, calc(100% - 3rem));
  pointer-events: none;
  z-index: 10;
}

.hud-column {
  background: rgba(6, 8, 18, 0.7);
  border: 1px solid rgba(120, 160, 255, 0.25);
  border-radius: 0.75rem;
  padding: 1rem 1.25rem;
  backdrop-filter: blur(8px);
  pointer-events: auto;
}

.hud-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
}

.hud h1,
.hud h2 {
  margin: 0 0 0.5rem;
  font-weight: 600;
}

.hud-header h1 {
  margin: 0;
}

.hud h1 {
  font-size: 1.25rem;
}

.hud h2 {
  font-size: 1.1rem;
}

.hint {
  margin: 0.25rem 0;
  font-size: 0.85rem;
  color: #aeb7d6;
}

.language-switch {
  display: inline-flex;
  position: relative;
}

.language-button {
  background: rgba(120, 160, 255, 0.18);
  border: 1px solid rgba(120, 160, 255, 0.45);
  border-radius: 0.5rem;
  padding: 0.25rem 0.6rem;
  color: inherit;
  font: inherit;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.language-button span {
  display: inline-flex;
  align-items: center;
}

.language-button .language-flag {
  font-size: 1.1rem;
}

.language-button .language-caret {
  font-size: 0.7rem;
  opacity: 0.85;
}

.language-button .language-name {
  font-size: 0.9rem;
}

.language-button:hover,
.language-button:focus-visible {
  background: rgba(120, 160, 255, 0.38);
  border-color: rgba(120, 160, 255, 0.7);
}

.language-menu {
  position: absolute;
  right: 0;
  top: calc(100% + 0.3rem);
  background: rgba(6, 8, 18, 0.95);
  border: 1px solid rgba(120, 160, 255, 0.35);
  border-radius: 0.6rem;
  padding: 0.35rem;
  display: none;
  flex-direction: column;
  gap: 0.25rem;
  min-width: 9.5rem;
  z-index: 40;
}

.language-menu.open {
  display: flex;
}

.language-option {
  background: transparent;
  border: none;
  color: inherit;
  font: inherit;
  padding: 0.3rem 0.55rem;
  text-align: left;
  cursor: pointer;
  border-radius: 0.45rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.language-option:hover,
.language-option:focus-visible {
  background: rgba(120, 160, 255, 0.25);
}

.language-option.active {
  background: rgba(120, 160, 255, 0.35);
  font-weight: 600;
}

.language-option span {
  display: inline-flex;
  align-items: center;
}

.language-option .language-flag {
  font-size: 1.05rem;
}

.stat {
  margin: 0.75rem 0 0;
  font-size: 0.95rem;
}

#speed-slider {
  width: 100%;
  margin-top: 0.75rem;
}

.transport-controls {
  margin-top: 0.6rem;
  display: flex;
  gap: 0.5rem;
  align-items: center;
}

.transport-controls button {
  width: 2.25rem;
  height: 2.25rem;
  font-size: 1.2rem;
  padding: 0;
  display: grid;
  place-items: center;
}

.time-buttons {
  margin-top: 0.65rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.22rem;
  flex-wrap: nowrap;
  overflow-x: auto;
  max-width: 100%;
}

.time-buttons button {
  padding: 0.15rem 0.28rem;
  font-size: 0.8rem;
  letter-spacing: -0.02em;
  white-space: nowrap;
}

.time-buttons .time-now {
  font-weight: 600;
  margin: 0 0.28rem;
}

.selection {
  min-height: 6rem;
  display: grid;
  gap: 0.25rem;
  font-size: 0.95rem;
}

.selection strong {
  font-size: 1.05rem;
}

.selection-actions {
  display: flex;
  gap: 0.5rem;
  margin-top: 0.75rem;
}

button {
  background: rgba(120, 160, 255, 0.15);
  color: inherit;
  border: 1px solid rgba(120, 160, 255, 0.35);
  border-radius: 0.5rem;
  padding: 0.4rem 0.75rem;
  font: inherit;
  cursor: pointer;
  transition: background 0.2s ease, border-color 0.2s ease;
}

button:hover {
  background: rgba(120, 160, 255, 0.35);
  border-color: rgba(120, 160, 255, 0.65);
}

button:disabled {
  opacity: 0.5;
  cursor: default;
}

.info-list {
  margin: 0;
  padding-left: 1.2rem;
  color: #c7d1f5;
  font-size: 0.9rem;
}

@media (max-width: 960px) {
  .hud {
    top: 1rem;
    left: 1rem;
    max-width: min(420px, calc(100% - 2rem));
  }

  .hud-column {
    padding: 0.85rem 1rem;
  }
}

@media (max-width: 640px) {
  .hud {
    top: 0.75rem;
    left: 0.75rem;
    right: 0.75rem;
    max-width: none;
    gap: 0.75rem;
  }

  .time-buttons {
    justify-content: flex-start;
  }
}