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

body {
  background: #0a0a0f;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  font-family: 'Segoe UI', system-ui, sans-serif;
  overflow: hidden;
}

#game-container {
  position: relative;
  border: 3px solid #2a4a2a;
  border-radius: 4px;
  box-shadow: 0 0 40px rgba(0, 80, 0, 0.3);
}

#game-canvas {
  display: block;
  cursor: crosshair;
  max-width: 100vw;
  max-height: calc(100vh - 24px);
}

#hud {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  padding: 12px 20px;
  background: linear-gradient(to bottom, rgba(0,0,0,0.7), transparent);
  pointer-events: none;
}

.hud-row {
  display: flex;
  gap: 24px;
  color: #a8d8a8;
  font-size: 16px;
  font-weight: 600;
  text-shadow: 0 1px 3px rgba(0,0,0,0.8);
}

.hud-row span {
  letter-spacing: 0.5px;
}

#health-display {
  color: #ff8888;
}

#bullets-display {
  color: #ffd700;
}

#pause-btn {
  position: absolute;
  top: 12px;
  right: 16px;
  z-index: 12;
  pointer-events: auto;
  padding: 8px 18px;
  font-size: 0.9rem;
}

/* Pause side panel — left side only so the map stays visible top-right */
.pause-panel {
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  width: min(900px, calc(100% - 220px));
  z-index: 9;
  background: rgba(5, 10, 5, 0.94);
  border-right: 2px solid #3d7a3d;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  pointer-events: auto;
}

.pause-panel.hidden {
  display: none;
}

.pause-panel .upgrade-scroll {
  width: 100%;
  height: 100%;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 16px 20px 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  -webkit-overflow-scrolling: touch;
}

.pause-panel .upgrade-scroll::-webkit-scrollbar {
  width: 8px;
}

.pause-panel .upgrade-scroll::-webkit-scrollbar-thumb {
  background: rgba(107, 255, 107, 0.35);
  border-radius: 4px;
}

/* Spacing for the extra Game Over button */
#gameover-screen .btn {
  margin: 6px;
}

.overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  background: rgba(5, 10, 5, 0.92);
  color: #c8e6c8;
  text-align: center;
  padding: 40px;
  z-index: 10;
}

/* Upgrade shop scrolls when many tank panels are unlocked */
#upgrade-screen {
  justify-content: flex-start;
  padding: 0;
  overflow: hidden;
}

#upgrade-screen .upgrade-scroll,
#upgrade-shop-content.upgrade-scroll {
  width: 100%;
  height: 100%;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 20px 24px 28px;
  display: flex;
  flex-direction: column;
  align-items: center;
  -webkit-overflow-scrolling: touch;
}

#upgrade-screen .upgrade-scroll::-webkit-scrollbar,
#upgrade-shop-content.upgrade-scroll::-webkit-scrollbar {
  width: 8px;
}

#upgrade-screen .upgrade-scroll::-webkit-scrollbar-thumb,
#upgrade-shop-content.upgrade-scroll::-webkit-scrollbar-thumb {
  background: rgba(107, 255, 107, 0.35);
  border-radius: 4px;
}

#upgrade-screen #next-level-btn,
#upgrade-shop-content #next-level-btn {
  margin-top: 8px;
  margin-bottom: 8px;
  flex-shrink: 0;
}

.overlay.hidden {
  display: none;
}

.overlay h1 {
  font-size: 3rem;
  color: #6bff6b;
  text-shadow: 0 0 20px rgba(107, 255, 107, 0.4);
  margin-bottom: 16px;
}

.overlay h2 {
  font-size: 2.2rem;
  color: #6bff6b;
  margin-bottom: 12px;
}

.overlay p {
  font-size: 1.1rem;
  margin-bottom: 8px;
  max-width: 480px;
  line-height: 1.5;
}

.controls-info {
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(107, 255, 107, 0.2);
  border-radius: 8px;
  padding: 16px 24px;
  margin: 20px 0 28px;
}

.controls-info p {
  margin-bottom: 4px;
  font-size: 0.95rem;
}

.btn {
  background: linear-gradient(135deg, #2d6a2d, #1a4a1a);
  color: #e0ffe0;
  border: 2px solid #4a8a4a;
  padding: 12px 32px;
  font-size: 1.1rem;
  font-weight: 600;
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.2s;
  letter-spacing: 0.5px;
}

.btn:hover {
  background: linear-gradient(135deg, #3d8a3d, #2d6a2d);
  border-color: #6bff6b;
  transform: translateY(-1px);
  box-shadow: 0 4px 15px rgba(107, 255, 107, 0.3);
}

.btn:active {
  transform: translateY(0);
}

.btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.btn-large {
  margin-top: 24px;
  padding: 14px 48px;
  font-size: 1.2rem;
}

.btn-reset {
  margin-top: 14px;
  padding: 10px 24px;
  font-size: 0.95rem;
  background: linear-gradient(135deg, #5a2a2a, #3a1a1a);
  border-color: #8a4444;
  color: #ffcccc;
}

.btn-reset:hover {
  background: linear-gradient(135deg, #7a3a3a, #5a2a2a);
  border-color: #ff8888;
  box-shadow: 0 4px 15px rgba(255, 100, 100, 0.25);
}

.save-info {
  color: #88cc88;
  font-size: 0.95rem;
  margin: 12px 0 4px;
  padding: 8px 16px;
  background: rgba(107, 255, 107, 0.08);
  border: 1px solid rgba(107, 255, 107, 0.2);
  border-radius: 6px;
}

#upgrade-bullets {
  color: #ffd700;
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 20px;
}

#upgrade-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  max-width: 920px;
}

.onetime-upgrade-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  max-width: 920px;
}

.onetime-note {
  color: #88aa88;
  font-size: 0.9rem;
  margin: 0 0 10px 0;
}

.upgrade-card.onetime-card.owned {
  border-color: rgba(107, 200, 255, 0.45);
  background: rgba(60, 100, 140, 0.15);
}

.upgrade-card.onetime-card.owned .upgrade-level span {
  color: #88ccff;
}

.onetime-btn.owned-btn,
.onetime-btn:disabled {
  opacity: 0.55;
  cursor: default;
}

.upgrade-section {
  width: 100%;
  max-width: 920px;
  margin-bottom: 14px;
}

.upgrade-section-toggle,
.ally-tank-toggle {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 10px;
  background: rgba(107, 255, 107, 0.08);
  border: 1px solid rgba(107, 255, 107, 0.3);
  color: #6bff6b;
  padding: 12px 16px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 1.05rem;
  font-weight: 600;
  font-family: inherit;
  text-align: left;
  transition: background 0.2s, border-color 0.2s;
}

.upgrade-section.ally-section .upgrade-section-toggle {
  background: rgba(68, 204, 136, 0.08);
  border-color: rgba(68, 204, 136, 0.35);
  color: #44cc88;
}

.upgrade-section-toggle:hover,
.ally-tank-toggle:hover {
  background: rgba(107, 255, 107, 0.14);
  border-color: rgba(107, 255, 107, 0.5);
}

.upgrade-section.ally-section .upgrade-section-toggle:hover {
  background: rgba(68, 204, 136, 0.14);
  border-color: rgba(68, 204, 136, 0.55);
}

.upgrade-section-label,
.ally-tank-title {
  flex-shrink: 0;
}

.toggle-icon {
  margin-left: auto;
  font-size: 0.85rem;
  transition: transform 0.25s ease;
}

.upgrade-section.collapsed .upgrade-section-toggle .toggle-icon,
.ally-tank-panel.collapsed .ally-tank-toggle .toggle-icon {
  transform: rotate(-90deg);
}

.upgrade-section-body,
.ally-tank-body {
  overflow: hidden;
  max-height: 3000px;
  opacity: 1;
  transition: max-height 0.3s ease, opacity 0.25s ease, padding 0.25s ease;
  padding-top: 12px;
}

.upgrade-section.collapsed .upgrade-section-body,
.ally-tank-panel.collapsed .ally-tank-body {
  max-height: 0;
  opacity: 0;
  padding-top: 0;
  pointer-events: none;
}

#ally-upgrade-panels {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.ally-tank-panel {
  border: 1px solid rgba(68, 204, 136, 0.2);
  border-radius: 8px;
  background: rgba(68, 204, 136, 0.03);
  overflow: hidden;
}

.ally-tank-toggle {
  background: rgba(68, 204, 136, 0.06);
  border: none;
  border-radius: 0;
  color: var(--ally-accent, #44cc88);
  font-size: 0.95rem;
  padding: 10px 14px;
}

.ally-tank-toggle:hover {
  background: rgba(68, 204, 136, 0.12);
}

.ally-tank-summary {
  flex: 1;
  font-size: 0.75rem;
  font-weight: 500;
  color: #88aa99;
  text-align: right;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.ally-tank-body {
  padding: 0 12px 12px;
}

.ally-tank-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 12px;
}

.ally-upgrade-note {
  color: #88aa99;
  font-size: 0.85rem;
  margin-bottom: 10px;
  max-width: 920px;
  text-align: center;
}

.upgrade-card.ally-card {
  border-color: rgba(68, 204, 136, 0.35);
}

.upgrade-card.ally-card:hover {
  border-color: rgba(68, 204, 136, 0.65);
}

.upgrade-card.ally-card h3 {
  color: #44cc88;
}

.upgrade-card {
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(107, 255, 107, 0.25);
  border-radius: 8px;
  padding: 16px;
  transition: border-color 0.2s;
}

.chassis-note {
  font-size: 0.85rem;
  color: #88bb88;
  margin-bottom: 12px;
  text-align: center;
}

.chassis-picker {
  display: flex;
  flex-direction: column;
  gap: 10px;
  width: 100%;
  max-width: 720px;
  margin-bottom: 8px;
}

.chassis-card {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 4px;
  width: 100%;
  text-align: left;
  background: rgba(255, 255, 255, 0.04);
  border: 2px solid rgba(107, 255, 107, 0.25);
  border-radius: 8px;
  padding: 12px 14px;
  cursor: pointer;
  color: #c8e6c8;
  transition: border-color 0.2s, background 0.2s;
}

.chassis-card:hover:not(.locked) {
  border-color: rgba(107, 255, 107, 0.55);
  background: rgba(107, 255, 107, 0.08);
}

.chassis-card.active {
  border-color: #ffd54a;
  background: rgba(255, 213, 74, 0.1);
  box-shadow: 0 0 12px rgba(255, 213, 74, 0.15);
}

.chassis-card.chassis-assault { border-left: 4px solid #6a7a58; }
.chassis-card.chassis-fortress { border-left: 4px solid #d4aa50; }
.chassis-card.chassis-striker { border-left: 4px solid #50a8d8; }
.chassis-card.chassis-sniper { border-left: 4px solid #78ecff; }

.chassis-card.chassis-fortress:hover:not(.locked) {
  box-shadow: 0 0 14px rgba(212, 170, 80, 0.2);
}
.chassis-card.chassis-striker:hover:not(.locked) {
  box-shadow: 0 0 14px rgba(80, 168, 216, 0.25);
}
.chassis-card.chassis-sniper:hover:not(.locked) {
  box-shadow: 0 0 14px rgba(120, 236, 255, 0.25);
}
.chassis-card.chassis-sniper.active {
  border-color: #78ecff;
  background: rgba(120, 236, 255, 0.08);
  box-shadow: 0 0 16px rgba(120, 236, 255, 0.2);
}
.chassis-card.chassis-sniper.active .chassis-name {
  color: #aaf4ff;
}

.chassis-card.locked {
  opacity: 0.45;
  cursor: not-allowed;
}

.chassis-name {
  font-weight: 700;
  font-size: 1rem;
  color: #6bff6b;
}

.chassis-card.active .chassis-name {
  color: #ffe082;
}

.chassis-tagline {
  font-size: 0.82rem;
  color: #99cc99;
  line-height: 1.35;
}

.chassis-active {
  font-size: 0.75rem;
  font-weight: 700;
  color: #ffd54a;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.chassis-upgrade-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
  width: 100%;
  max-width: 920px;
  margin-top: 4px;
}

.chassis-upgrade-grid.hidden,
#upgrade-grid.hidden {
  display: none;
}

.upgrade-card.chassis-upgrade-card h3 {
  color: #aadcf0;
}

.chassis-sniper.active ~ .upgrade-section-body .chassis-upgrade-grid .chassis-upgrade-card h3,
#chassis-upgrade-grid .chassis-upgrade-card h3 {
  color: #aadcf0;
}

@media (max-width: 900px) {
  .chassis-upgrade-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.upgrade-card:hover {
  border-color: rgba(107, 255, 107, 0.5);
}

.upgrade-card.locked {
  opacity: 0.45;
  border-color: rgba(255, 255, 255, 0.12);
}

.upgrade-card.locked:hover {
  border-color: rgba(255, 255, 255, 0.2);
}

.upgrade-card.locked h3 {
  color: #888;
}

.upgrade-card h3 {
  color: #6bff6b;
  margin-bottom: 6px;
  font-size: 1.1rem;
}

.upgrade-card p {
  font-size: 0.85rem;
  margin-bottom: 4px;
}

.upgrade-cost {
  color: #ffd700;
}

.upgrade-btn {
  margin-top: 10px;
  padding: 8px 16px;
  font-size: 0.9rem;
  width: 100%;
}

@media (max-width: 750px) {
  #upgrade-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .ally-tank-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* Developer panel — fixed outside the game canvas, bottom-right of the page */
#dev-panel {
  position: fixed;
  bottom: 16px;
  right: 16px;
  z-index: 1000;
  background: rgba(10, 10, 20, 0.92);
  border: 2px solid #6655cc;
  border-radius: 8px;
  padding: 10px 12px;
  min-width: 220px;
  font-size: 12px;
  color: #ccc;
  box-shadow: 0 4px 20px rgba(100, 80, 200, 0.35);
}

#dev-panel.hidden {
  display: none;
}

#dev-panel.collapsed #dev-body {
  display: none;
}

.dev-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
  color: #aa99ff;
  font-weight: 700;
  font-size: 11px;
  letter-spacing: 1px;
}

#dev-toggle-btn {
  background: transparent;
  border: 1px solid #6655cc;
  color: #aa99ff;
  border-radius: 4px;
  width: 22px;
  height: 22px;
  cursor: pointer;
  font-size: 14px;
  line-height: 1;
  padding: 0;
}

.dev-row {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 6px;
}

.dev-row label {
  flex-shrink: 0;
  width: 36px;
}

#dev-level-input {
  width: 52px;
  padding: 4px 6px;
  border: 1px solid #554488;
  border-radius: 4px;
  background: #1a1a2a;
  color: #eee;
  font-size: 12px;
}

.dev-buttons {
  flex-wrap: wrap;
}

.btn-dev {
  padding: 5px 8px;
  font-size: 11px;
  border-color: #6655cc;
  background: linear-gradient(135deg, #443388, #332266);
  flex: 1;
  min-width: 0;
}

.btn-dev:hover {
  border-color: #aa99ff;
  background: linear-gradient(135deg, #554499, #443377);
}

.dev-hint {
  margin: 8px 0 0;
  font-size: 10px;
  color: #888;
  line-height: 1.4;
}