:root {
  --bg: #04060d;
  --ink: #e8f6ff;
  --muted: #8ea0b8;
  --cyan: #3cf0ff;
  --magenta: #ff3dad;
  --gold: #ffe27a;
  --lime: #7dff9a;
  --crimson: #ff3355;
  --panel: rgba(6, 10, 22, 0.82);
  --stroke: rgba(60, 240, 255, 0.45);
  --hp: #ff4d6d;
  --xp: #3cf0ff;
  --boss: #ff3dad;
  --shadow: 0 0 28px rgba(60, 240, 255, 0.18);
  color-scheme: dark;
}

/* Arena stays dark neon even when the OS is in light mode so HUD text never inverts. */

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

html,
body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: var(--bg);
  color: var(--ink);
  font-family: Rajdhani, "Segoe UI", sans-serif;
}

canvas {
  display: block;
  width: 100%;
  height: 100%;
  background: #03040a;
}

#vignette {
  position: fixed;
  inset: 0;
  pointer-events: none;
  background: radial-gradient(ellipse at center, transparent 48%, rgba(0, 0, 0, 0.55) 100%);
  z-index: 2;
}

#scanlines {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 3;
  opacity: 0.07;
  background: repeating-linear-gradient(
    to bottom,
    rgba(255, 255, 255, 0.16) 0,
    rgba(255, 255, 255, 0.16) 1px,
    transparent 1px,
    transparent 3px
  );
}

.hidden {
  display: none !important;
}

#hud {
  position: fixed;
  inset: 0;
  z-index: 4;
  pointer-events: none;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 16px 22px 18px;
  color: #e8f6ff;
  text-shadow: 0 1px 2px #000, 0 0 10px rgba(0, 0, 0, 0.85);
}

.hud-top {
  display: grid;
  grid-template-columns: minmax(180px, 240px) 1fr minmax(180px, 240px);
  align-items: start;
  gap: 16px;
}

.hud-label,
.hud-xp-meta,
.timer-readout,
.boss-phase,
.boss-name {
  font-family: Orbitron, Rajdhani, sans-serif;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.hud-hp,
.hud-bottom {
  background: rgba(3, 6, 14, 0.62);
  border: 1px solid rgba(60, 240, 255, 0.16);
  padding: 8px 10px 10px;
}

.hud-label {
  font-size: 12px;
  color: #c5d4e8;
  margin-bottom: 6px;
}

#hp-readout {
  color: #f4fbff;
  font-size: 12px;
}

.bar {
  height: 14px;
  border: 1px solid var(--stroke);
  background: rgba(0, 0, 0, 0.45);
  box-shadow: var(--shadow);
  position: relative;
  overflow: hidden;
}

.bar-fill {
  height: 100%;
  width: 100%;
  transform-origin: left center;
  transform: scaleX(1);
}

.hp-fill {
  background: linear-gradient(90deg, #7a1024, var(--hp) 55%, #ffd0d8);
}

.xp-fill {
  background: linear-gradient(90deg, #0a5a72, var(--xp) 60%, #d7fbff);
}

.boss-fill {
  background: linear-gradient(90deg, #5a1038, var(--boss) 50%, #ffd0f0);
}

.hud-center {
  text-align: center;
}

.wave-readout {
  font-family: Orbitron, sans-serif;
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 0.12em;
  color: var(--cyan);
  text-shadow: 0 0 16px rgba(60, 240, 255, 0.55);
}

.timer-readout {
  margin-top: 4px;
  font-size: 13px;
  color: #c5d4e8;
}

.boss-hud {
  margin: 10px auto 0;
  width: min(520px, 86vw);
}

.boss-name {
  font-size: 12px;
  color: var(--magenta);
  text-shadow: 0 0 12px rgba(255, 61, 173, 0.7);
  margin-bottom: 5px;
}

.boss-track {
  height: 16px;
  border-color: rgba(255, 61, 173, 0.65);
}

.boss-phase {
  margin-top: 4px;
  font-size: 11px;
  color: #ffb7e2;
}

.hud-bottom {
  width: min(920px, 92vw);
  margin: 0 auto;
}

.hud-xp-meta {
  display: flex;
  justify-content: space-between;
  font-size: 13px;
  color: #c5d4e8;
  margin-bottom: 6px;
}

#level-readout,
#xp-readout {
  color: #f4fbff;
}

.xp-track {
  height: 12px;
}

.toast {
  position: fixed;
  top: 28%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 6;
  pointer-events: none;
  font-family: Orbitron, sans-serif;
  font-size: clamp(22px, 4vw, 42px);
  font-weight: 800;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: #fff;
  text-shadow: 0 0 22px rgba(60, 240, 255, 0.85), 0 0 48px rgba(255, 61, 173, 0.45);
  text-align: center;
}

.screen {
  position: fixed;
  inset: 0;
  z-index: 8;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(2, 4, 10, 0.62);
  padding: 24px;
}

.panel {
  width: min(720px, 94vw);
  background: var(--panel);
  border: 1px solid var(--stroke);
  box-shadow: var(--shadow), inset 0 0 40px rgba(60, 240, 255, 0.04);
  padding: 36px 40px 32px;
  text-align: center;
}

.start-panel h1,
.end-panel h2,
.level-panel h2,
.pause-panel h2 {
  font-family: Orbitron, sans-serif;
  font-weight: 800;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.start-panel h1 {
  font-size: clamp(32px, 6vw, 56px);
  color: var(--cyan);
  text-shadow: 0 0 24px rgba(60, 240, 255, 0.45);
  margin-bottom: 10px;
}

.kicker {
  font-family: Orbitron, sans-serif;
  font-size: 11px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--magenta);
  margin-bottom: 10px;
}

.goal {
  font-size: 22px;
  font-weight: 700;
  color: var(--gold);
  margin-bottom: 22px;
}

.controls {
  list-style: none;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.7;
  margin-bottom: 18px;
}

kbd {
  display: inline-block;
  min-width: 1.6em;
  padding: 0 6px;
  border: 1px solid var(--stroke);
  background: rgba(8, 16, 32, 0.8);
  color: var(--cyan);
  font-family: Orbitron, monospace;
  font-size: 12px;
}

.best-run {
  min-height: 1.4em;
  color: var(--lime);
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 16px;
}

.prompt,
.hint {
  color: var(--muted);
  font-size: 15px;
}

.prompt {
  color: var(--cyan);
  font-family: Orbitron, sans-serif;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-size: 13px;
  animation: pulse 1.6s ease-in-out infinite;
}

.upgrade-row {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  width: 100%;
  margin: 22px 0 16px;
}

.card {
  appearance: none;
  -webkit-appearance: none;
  font: inherit;
  width: auto;
  min-width: 0;
  min-height: 214px;
  padding: 18px 12px 16px;
  border: 1px solid var(--stroke);
  background-color: #0a1220;
  background-image: linear-gradient(180deg, rgba(16, 28, 48, 0.96), rgba(6, 10, 20, 0.96));
  color: #e8f6ff;
  cursor: pointer;
  text-align: center;
  box-shadow: 0 0 0 rgba(60, 240, 255, 0);
}

.card:hover,
.card.is-selected {
  border-color: var(--cyan);
  box-shadow: 0 0 22px rgba(60, 240, 255, 0.28);
  transform: translateY(-3px);
}

.card:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 3px;
}

.card-key {
  font-family: Orbitron, sans-serif;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--cyan);
  margin-bottom: 10px;
}

.card-icon {
  width: 54px;
  height: 54px;
  margin: 0 auto 12px;
  border-radius: 50%;
  border: 1px solid currentColor;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-family: Orbitron, sans-serif;
}

.card-name {
  font-family: Orbitron, sans-serif;
  font-size: 14px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 8px;
}

.card-desc {
  font-size: 15px;
  color: #b7c6da;
  line-height: 1.35;
}

@media (max-width: 700px) {
  .upgrade-row {
    grid-template-columns: 1fr;
  }

  .card {
    min-height: 0;
  }
}

.card-stack {
  margin-top: 10px;
  font-size: 12px;
  color: var(--gold);
}

.stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px 20px;
  margin: 22px auto;
  width: min(420px, 100%);
  text-align: left;
}

.stats div {
  display: flex;
  justify-content: space-between;
  border-bottom: 1px solid rgba(142, 160, 184, 0.25);
  padding-bottom: 6px;
  font-size: 17px;
}

.stats dt {
  color: var(--muted);
}

.stats dd {
  font-family: Orbitron, sans-serif;
  font-size: 14px;
  color: var(--cyan);
}

.restart {
  appearance: none;
  border: 1px solid var(--cyan);
  background: rgba(60, 240, 255, 0.1);
  color: var(--cyan);
  font-family: Orbitron, sans-serif;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-size: 13px;
  padding: 12px 28px;
  cursor: pointer;
  margin-bottom: 12px;
}

.restart:hover,
.restart:focus-visible {
  background: rgba(60, 240, 255, 0.22);
  outline: none;
}

.kicker.defeat {
  color: var(--crimson);
}

.kicker.victory {
  color: var(--lime);
}

@keyframes pulse {
  0%,
  100% { opacity: 1; }
  50% { opacity: 0.45; }
}

@media (prefers-reduced-motion: reduce) {
  .prompt,
  .card {
    animation: none !important;
    transition: none !important;
  }

  .card:hover,
  .card.is-selected {
    transform: none;
  }

  #scanlines {
    display: none;
  }
}