:root {
  --bg: #000000;
  --ink: #8ef9c9;
  --ink-dim: rgba(142, 249, 201, 0.72);
  --panel: rgba(4, 10, 8, 0.92);
  --panel-edge: rgba(73, 255, 176, 0.18);
  --accent: #19f58c;
  --accent-strong: #08a65f;
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.42);
  --font-display: "Share Tech Mono", "OCR A Std", "OCR A Extended", monospace;
  --font-title: "VT323", "Share Tech Mono", monospace;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  height: 100vh;
  overflow: hidden;
  font-family: var(--font-display);
  color: var(--ink);
  background:
    radial-gradient(circle at top left, rgba(12, 112, 76, 0.25), transparent 30%),
    radial-gradient(circle at bottom right, rgba(18, 74, 130, 0.2), transparent 34%),
    #000;
}

.app-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  gap: 28px;
  height: 100vh;
  padding: 28px;
}

.stage-panel,
.control-panel {
  background: var(--panel);
  border: 1px solid var(--panel-edge);
  border-radius: 28px;
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
}

.stage-panel {
  display: flex;
  flex-direction: column;
  padding: 26px;
  position: sticky;
  top: 28px;
  height: calc(100vh - 56px);
}

.stage-header {
  margin-bottom: 16px;
}

h1 {
  margin: 0;
  font-family: var(--font-title);
  font-size: clamp(1.9rem, 2.7vw, 3rem);
  line-height: 0.9;
  font-weight: 400;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.subtitle {
  max-width: 56rem;
  margin: 8px 0 0;
  font-size: 0.92rem;
  line-height: 1.5;
  color: var(--ink-dim);
}

.stage-frame {
  position: relative;
  flex: 1;
  min-height: 0;
  border-radius: 26px;
  overflow: hidden;
  background:
    linear-gradient(180deg, rgba(3, 14, 9, 0.92), rgba(0, 5, 7, 0.98)),
    repeating-linear-gradient(
      0deg,
      rgba(120, 255, 198, 0.04) 0,
      rgba(120, 255, 198, 0.04) 2px,
      transparent 2px,
      transparent 5px
    );
  border: 1px solid rgba(86, 255, 185, 0.14);
  box-shadow: inset 0 0 0 1px rgba(16, 255, 148, 0.08);
}

#visualizer {
  display: block;
  width: 100%;
  height: 100%;
}

.hud {
  position: absolute;
  z-index: 2;
  min-width: 120px;
  padding: 10px 14px;
  border: 1px solid rgba(54, 255, 168, 0.22);
  border-radius: 12px;
  background: rgba(2, 12, 9, 0.88);
  box-shadow: 0 0 22px rgba(16, 255, 148, 0.08);
}

.hud-target {
  top: 16px;
  left: 16px;
}

.hud-score {
  top: 16px;
  right: 16px;
  text-align: right;
}

.hud-label {
  display: block;
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(142, 249, 201, 0.56);
}

.hud strong {
  display: block;
  margin-top: 4px;
  font-family: var(--font-title);
  font-size: 1.8rem;
  font-weight: 400;
  letter-spacing: 0.08em;
}

.game-dialog {
  position: absolute;
  inset: 0;
  z-index: 3;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.62);
}

.game-dialog p {
  margin: 0;
  padding: 22px 28px;
  border: 1px solid rgba(54, 255, 168, 0.32);
  border-radius: 14px;
  background: rgba(2, 12, 9, 0.96);
  color: var(--ink);
  font-family: var(--font-title);
  font-size: clamp(1.7rem, 3.2vw, 2.7rem);
  text-align: center;
  letter-spacing: 0.08em;
  box-shadow: 0 0 36px rgba(16, 255, 148, 0.12);
  white-space: pre-line;
}

.is-hidden {
  display: none;
}

.control-panel {
  display: flex;
  flex-direction: column;
  padding: 28px 24px 24px;
  max-height: calc(100vh - 56px);
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: rgba(56, 255, 173, 0.45) transparent;
}

.control-panel.game-only {
  justify-content: flex-start;
}

.control-stack {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.control {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.control span,
.legend p,
.start-button,
select,
input {
  font-family: var(--font-display);
}

.control span {
  font-size: 1.05rem;
}

.control strong {
  font-size: 1rem;
  color: rgba(142, 249, 201, 0.76);
}

.control.is-hidden {
  display: none;
}

input[type="range"] {
  width: 100%;
  accent-color: var(--accent);
  filter: saturate(1.2);
}

select {
  width: 100%;
  padding: 12px 14px;
  font-size: 1rem;
  border-radius: 14px;
  border: 1px solid rgba(54, 255, 168, 0.2);
  background: rgba(3, 16, 11, 0.95);
  color: var(--ink);
  box-shadow: inset 0 0 0 1px rgba(86, 255, 185, 0.04);
}

.start-button {
  margin-top: 28px;
  width: 100%;
  border: 0;
  border-radius: 12px;
  padding: 18px 20px;
  font-size: 1.2rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #04120c;
  background: linear-gradient(135deg, var(--accent) 0%, #89ffd0 100%);
  cursor: pointer;
  transition: transform 150ms ease, box-shadow 150ms ease, filter 150ms ease;
  box-shadow: 0 0 30px rgba(25, 245, 140, 0.18);
}

.start-button:hover,
.secondary-button:hover {
  transform: translateY(-1px);
  filter: saturate(1.05);
}

.start-button:active,
.secondary-button:active {
  transform: translateY(1px);
}

.secondary-button {
  margin-top: 12px;
  width: 100%;
  border: 1px solid rgba(54, 255, 168, 0.24);
  border-radius: 12px;
  padding: 15px 20px;
  font-size: 1.1rem;
  color: var(--ink);
  background: rgba(3, 16, 11, 0.9);
  cursor: pointer;
  transition: transform 150ms ease, box-shadow 150ms ease, filter 150ms ease;
  box-shadow: inset 0 0 0 1px rgba(86, 255, 185, 0.04);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.secondary-button-accent {
  border-color: rgba(57, 180, 255, 0.28);
  box-shadow: 0 0 28px rgba(57, 180, 255, 0.1);
}

.secondary-button:disabled {
  opacity: 0.45;
  cursor: not-allowed;
  transform: none;
  filter: none;
}

.legend {
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid rgba(54, 255, 168, 0.14);
}

.legend p {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 12px;
  font-size: 0.95rem;
  color: var(--ink-dim);
}

.legend-chip {
  width: 18px;
  height: 18px;
  flex: 0 0 18px;
  border-radius: 999px;
}

.legend-chip.wall {
  background: linear-gradient(135deg, #1cf6a1, #39b4ff);
}

.legend-chip.ball {
  background: linear-gradient(135deg, #39b4ff, #ff4fd8);
}

.control-panel::-webkit-scrollbar {
  width: 10px;
}

.control-panel::-webkit-scrollbar-thumb {
  background: rgba(56, 255, 173, 0.34);
  border-radius: 999px;
}

.control-panel::-webkit-scrollbar-track {
  background: transparent;
}