:root {
  --bg: #08080f;
  --panel: #131325;
  --panel-light: #1f1f3a;
  --border: #2a2a4a;
  --accent: #5af7ff;
  --accent-dim: #2a8aa0;
  --danger: #ff4060;
  --warning: #ffb020;
  --ok: #50ff80;
  --text: #d0d0f0;
  --text-dim: #7878a8;
  --ore: #d8a050;
  --plate: #80d0e0;
  --bullet: #c0c0d0;
  --missile: #ff8050;
  --power: #ffe040;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
  -webkit-touch-callout: none;
}

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: var(--bg);
  color: var(--text);
  font-family: 'Consolas', 'Courier New', monospace;
  font-size: 14px;
  touch-action: none;
  overscroll-behavior: none;
}

#game-container {
  position: relative;
  width: 100vw;
  /* Layered fallbacks: var(--vh) set by JS from visualViewport.height is the
     most reliable across mobile browsers (handles Vivaldi/Firefox bottom UI),
     dvh covers modern Chrome/Safari, vh is the legacy fallback. */
  height: 100vh;
  height: 100dvh;
  height: var(--vh, 100dvh);
  overflow: hidden;
}

#game-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  touch-action: none;
  background: radial-gradient(ellipse at center, #10102a 0%, #050510 70%, #000005 100%);
}

#top-hud {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  display: flex;
  justify-content: space-between;
  padding: 6px 8px;
  gap: 6px;
  z-index: 10;
  pointer-events: none;
  flex-wrap: wrap;
}

.hud-section {
  display: flex;
  gap: 6px;
  align-items: center;
  background: rgba(19,19,37,0.92);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 4px 10px;
  pointer-events: auto;
  white-space: nowrap;
}

.hud-section .label {
  color: var(--text-dim);
  font-size: 10px;
  letter-spacing: 1px;
  text-transform: uppercase;
}

.hud-section.inventory { gap: 12px; }
.inv-item { display: flex; gap: 4px; align-items: center; }
.sym { display: inline-block; font-weight: bold; }
.sym-ore { color: var(--ore); }
.sym-plate { color: var(--plate); }
.sym-bullet { color: var(--bullet); }
.sym-missile { color: var(--missile); }
.sym-power { color: var(--power); }

#build-menu {
  /* Fixed to the viewport so it tracks the visible area even when the
     container size lags behind dynamic browser UI changes. The actual
     `bottom` offset is updated by JS via --menu-bottom-offset to push
     the menu up past any browser UI that overlays the bottom (e.g.
     Vivaldi's bottom address bar / tab strip). */
  position: fixed;
  bottom: var(--menu-bottom-offset, 0px);
  left: 0;
  right: 0;
  display: flex;
  justify-content: center;
  gap: 3px;
  padding: 6px 4px calc(6px + env(safe-area-inset-bottom));
  background: linear-gradient(0deg, rgba(8,8,15,0.95) 0%, rgba(8,8,15,0) 100%);
  z-index: 50;
  flex-wrap: wrap;
}

.build-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  background: var(--panel);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 4px 6px;
  cursor: pointer;
  border-radius: 4px;
  font-family: inherit;
  min-width: 56px;
  transition: background 0.1s, border-color 0.1s, transform 0.05s;
  -webkit-user-select: none;
  position: relative;
}

.build-btn .hotkey {
  position: absolute;
  top: 2px;
  right: 4px;
  font-size: 9px;
  color: var(--text-dim);
  font-weight: bold;
  letter-spacing: 0;
  pointer-events: none;
}
.build-btn:hover .hotkey, .build-btn.active .hotkey { color: var(--accent); }

.build-btn:hover { background: var(--panel-light); border-color: var(--accent-dim); }
.build-btn:active { transform: scale(0.96); }
.build-btn.active { background: var(--accent-dim); border-color: var(--accent); color: #fff; }
.build-btn.disabled { opacity: 0.4; pointer-events: none; }

.build-btn .icon { font-size: 18px; line-height: 1; }
.build-btn .label { font-size: 9px; margin-top: 2px; letter-spacing: 0.5px; }
.build-btn .cost { font-size: 9px; color: var(--text-dim); margin-top: 1px; }
.build-btn.active .cost { color: var(--text); }

.sym-harvester { color: #80c0ff; }
.sym-refinery { color: var(--plate); }
.sym-gun { color: var(--bullet); }
.sym-missile-turret { color: var(--missile); }
.sym-laser { color: var(--power); }
.sym-bullet-plant { color: var(--bullet); }
.sym-missile-plant { color: var(--missile); }
.sym-power-plant { color: var(--power); }

#tool-hint {
  position: absolute;
  bottom: 110px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(19,19,37,0.95);
  border: 1px solid var(--accent-dim);
  padding: 5px 10px;
  border-radius: 4px;
  color: var(--accent);
  font-size: 11px;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.15s;
  z-index: 10;
  white-space: nowrap;
}
#tool-hint.visible { opacity: 1; }

#mod-list {
  position: absolute;
  top: 46px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 4px;
  flex-wrap: wrap;
  justify-content: center;
  max-width: calc(100% - 16px);
  padding: 0 8px;
  z-index: 9;
  pointer-events: none;
}
#mod-list:empty { display: none; }
.mod-badge {
  display: inline-flex;
  gap: 5px;
  align-items: center;
  background: rgba(19, 19, 37, 0.92);
  border: 1px solid var(--accent-dim);
  border-radius: 12px;
  padding: 2px 9px;
  font-size: 11px;
  color: var(--text);
  pointer-events: auto;
  cursor: help;
  white-space: nowrap;
}
.mod-badge .name { color: var(--accent); font-weight: bold; }
.mod-badge .lvl { color: var(--ok); letter-spacing: 1px; }
@media (max-width: 600px) {
  #mod-list { top: 76px; }
  .mod-badge { font-size: 10px; padding: 2px 7px; }
}

#info-panel {
  position: absolute;
  top: 56px;
  left: 8px;
  width: 230px;
  max-height: calc(100vh - 200px);
  overflow-y: auto;
  background: rgba(19,19,37,0.95);
  border: 1px solid var(--accent-dim);
  border-radius: 4px;
  z-index: 20;
  padding: 8px 10px;
  font-size: 12px;
  pointer-events: auto;
}
.info-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 6px;
  padding-bottom: 4px;
  border-bottom: 1px solid var(--border);
}
#info-title { color: var(--accent); font-weight: bold; letter-spacing: 1px; }
#info-close {
  background: none; border: none; color: var(--text-dim);
  cursor: pointer; font-size: 20px; line-height: 1; padding: 0 4px;
  font-family: inherit;
}
#info-close:hover { color: var(--text); }
.info-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin: 3px 0;
  gap: 8px;
}
.info-row .label { color: var(--text-dim); }
.info-row .value { color: var(--text); text-align: right; }
.info-bar {
  height: 4px;
  background: rgba(0,0,0,0.4);
  border: 1px solid var(--border);
  border-radius: 2px;
  overflow: hidden;
  margin: 1px 0 4px;
}
.info-bar > span { display: block; height: 100%; transition: width 0.15s; }
.info-section {
  margin-top: 8px;
  padding-top: 6px;
  border-top: 1px dashed var(--border);
}
#info-demolish {
  width: 100%;
  margin-top: 8px;
  background: transparent;
  border: 1px solid var(--danger);
  color: var(--danger);
  padding: 6px;
  cursor: pointer;
  border-radius: 3px;
  font-family: inherit;
  font-size: 11px;
}
#info-demolish:hover { background: var(--danger); color: var(--bg); }

#info-upgrades {
  margin-top: 8px;
  padding-top: 6px;
  border-top: 1px dashed var(--border);
}
.upgrade-row {
  display: flex;
  align-items: center;
  gap: 6px;
  margin: 3px 0;
}
.upg-label { color: var(--text-dim); flex: 0 0 54px; font-size: 11px; }
.upg-tiers { flex: 1; color: var(--accent); letter-spacing: 2px; font-size: 13px; }
.upg-btn {
  background: transparent;
  border: 1px solid var(--accent-dim);
  color: var(--accent);
  padding: 3px 8px;
  cursor: pointer;
  border-radius: 3px;
  font-family: inherit;
  font-size: 11px;
  min-width: 56px;
}
.upg-btn:hover:not(:disabled) { background: var(--accent-dim); color: var(--bg); }
.upg-btn:disabled { opacity: 0.4; cursor: not-allowed; }
.upg-btn.maxed { color: var(--ok); border-color: var(--ok); opacity: 1; }

#info-conveyor-actions {
  display: flex;
  gap: 4px;
  margin-top: 8px;
}
#info-conveyor-actions[hidden] { display: none; }
.info-action-btn {
  flex: 1;
  background: transparent;
  border: 1px solid var(--accent-dim);
  color: var(--accent);
  padding: 6px 4px;
  cursor: pointer;
  border-radius: 3px;
  font-family: inherit;
  font-size: 11px;
}
.info-action-btn:hover:not(:disabled) { background: var(--accent-dim); color: var(--bg); }
.info-action-btn:disabled { opacity: 0.4; cursor: not-allowed; }
@media (max-width: 600px) {
  /* Bottom-sheet info panel above the build menu — full width, comfortable taps */
  #info-panel {
    top: auto;
    left: 8px;
    right: 8px;
    bottom: 150px;
    width: auto;
    max-width: none;
    max-height: calc(var(--vh, 100vh) - 320px);
    font-size: 13px;
    padding: 10px 12px;
    box-shadow: 0 -4px 16px rgba(0, 0, 0, 0.4);
  }
  .info-header { margin-bottom: 8px; padding-bottom: 6px; }
  #info-title { font-size: 14px; }
  #info-close { font-size: 26px; padding: 2px 10px; line-height: 1; }
  .info-row { margin: 5px 0; }
  .info-row .label, .info-row .value { font-size: 13px; }
  .info-bar { height: 5px; }
  /* Bigger tap targets for action buttons */
  #info-demolish, .info-action-btn, .upg-btn {
    padding: 10px 12px;
    font-size: 12px;
    min-height: 40px;
  }
  #info-conveyor-actions { gap: 6px; margin-top: 10px; }
  #info-upgrades { margin-top: 10px; padding-top: 8px; }
  .upgrade-row { margin: 5px 0; gap: 8px; }
  .upg-label { font-size: 12px; flex: 0 0 64px; }
  .upg-tiers { font-size: 15px; }
  .upg-btn { min-width: 72px; }
}

#start-wave-btn {
  position: absolute;
  top: 50px;
  right: 8px;
  background: var(--ok);
  color: var(--bg);
  border: none;
  padding: 8px 14px;
  font-weight: bold;
  cursor: pointer;
  border-radius: 4px;
  z-index: 10;
  font-family: inherit;
  font-size: 13px;
  box-shadow: 0 0 12px rgba(80,255,128,0.4);
  animation: pulse 1.5s infinite;
}
@keyframes pulse {
  0%, 100% { box-shadow: 0 0 12px rgba(80,255,128,0.4); }
  50% { box-shadow: 0 0 20px rgba(80,255,128,0.7); }
}

.hud-btn {
  font-family: inherit;
  color: var(--text);
  font-size: 16px;
  line-height: 1;
  cursor: pointer;
  transition: background 0.1s, color 0.1s, border-color 0.1s;
}
.hud-btn:hover { background: var(--panel-light); border-color: var(--accent-dim); color: var(--accent); }
.hud-btn:active { transform: scale(0.96); }
.hud-btn.paused { color: var(--ok); border-color: var(--ok); }

#mod-overlay {
  position: absolute;
  inset: 0;
  background: rgba(8, 8, 15, 0.82);
  backdrop-filter: blur(3px);
  -webkit-backdrop-filter: blur(3px);
  z-index: 95;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  pointer-events: auto;
}
#mod-overlay[hidden] { display: none; }
.mod-modal {
  background: var(--panel);
  border: 2px solid var(--accent);
  border-radius: 8px;
  padding: 22px 24px;
  max-width: 560px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  text-align: center;
  box-shadow: 0 0 32px rgba(90, 247, 255, 0.25);
}
.mod-modal h2 {
  color: var(--accent);
  letter-spacing: 4px;
  margin-bottom: 6px;
}
.mod-sub {
  color: var(--text-dim);
  font-size: 12px;
  margin-bottom: 18px;
}
.mod-options {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 14px;
}
.mod-card {
  display: flex;
  flex-direction: column;
  gap: 6px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 14px 12px;
  color: var(--text);
  font-family: inherit;
  text-align: left;
  cursor: pointer;
  transition: border-color 0.1s, transform 0.05s, background 0.1s;
}
.mod-card:hover { border-color: var(--accent); background: var(--panel-light); }
.mod-card:active { transform: scale(0.98); }
.mod-card .mod-name {
  color: var(--accent);
  font-weight: bold;
  font-size: 14px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.mod-card .mod-lvl {
  font-size: 11px;
  color: var(--text-dim);
  letter-spacing: 1px;
  font-weight: normal;
}
.mod-card .mod-pos {
  color: var(--ok);
  font-size: 12px;
  line-height: 1.35;
}
.mod-card .mod-neg {
  color: var(--danger);
  font-size: 12px;
  line-height: 1.35;
}
#mod-skip {
  background: transparent;
  border: 1px solid var(--text-dim);
  color: var(--text-dim);
  padding: 8px 18px;
  cursor: pointer;
  border-radius: 4px;
  font-family: inherit;
  font-size: 12px;
}
#mod-skip:hover { color: var(--text); border-color: var(--text); }
@media (max-width: 600px) {
  .mod-options { grid-template-columns: 1fr; }
  .mod-modal h2 { font-size: 20px; letter-spacing: 2px; }
  .mod-modal { padding: 16px 14px; }
}

#pause-overlay {
  position: absolute;
  inset: 0;
  background: rgba(8,8,15,0.7);
  backdrop-filter: blur(2px);
  -webkit-backdrop-filter: blur(2px);
  z-index: 90;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
}
#pause-overlay[hidden] { display: none; }
#pause-overlay h2 {
  color: var(--accent);
  font-size: 36px;
  letter-spacing: 8px;
}
#pause-overlay p { color: var(--text-dim); }
#pause-overlay b { color: var(--accent); }
#resume-btn {
  background: var(--accent);
  color: var(--bg);
  border: none;
  padding: 10px 22px;
  cursor: pointer;
  border-radius: 4px;
  font-family: inherit;
  font-weight: bold;
  letter-spacing: 1px;
  margin-top: 8px;
}
#resume-btn:hover { filter: brightness(1.2); }

#game-over, #intro {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: var(--panel);
  border: 2px solid var(--accent);
  padding: 24px 32px;
  text-align: center;
  border-radius: 6px;
  z-index: 100;
  max-width: 90vw;
}
#game-over { border-color: var(--danger); }
#game-over h1 { color: var(--danger); margin-bottom: 12px; letter-spacing: 2px; }
#game-over p { margin-bottom: 16px; }

#intro h2 { color: var(--accent); letter-spacing: 6px; font-size: 32px; margin-bottom: 4px; }
#intro .tagline { color: var(--text-dim); font-size: 12px; letter-spacing: 2px; margin-bottom: 16px; }
#intro ul { text-align: left; margin: 0 auto 16px; max-width: 320px; }
#intro li { margin-bottom: 6px; font-size: 12px; line-height: 1.5; }
#intro b { color: var(--accent); }

#restart-btn, #intro-close {
  background: var(--accent);
  color: var(--bg);
  border: none;
  padding: 10px 22px;
  cursor: pointer;
  border-radius: 4px;
  font-family: inherit;
  font-weight: bold;
  letter-spacing: 1px;
}
#restart-btn:hover, #intro-close:hover { filter: brightness(1.2); }

/* Tablet & landscape phones — tighten HUD, hide keyboard hotkeys */
@media (max-width: 720px) {
  .hud-section { padding: 4px 8px; font-size: 12px; }
  .hud-section .label { font-size: 10px; }
  .hud-section.inventory { gap: 10px; }
  .build-btn .hotkey { display: none; }
  #start-wave-btn { padding: 8px 14px; font-size: 12px; }
}

/* Phone portrait — big touch-friendly build buttons, 5-per-row layout */
@media (max-width: 600px) {
  .hud-section .label { display: none; }
  /* Bigger tap targets for HUD buttons (compound selector beats .hud-section padding) */
  .hud-btn.hud-section { font-size: 20px; padding: 6px 10px; }

  #top-hud { padding: 4px 4px; gap: 4px; }
  /* Status chips: compact text so all 4 fit in one row alongside the buttons */
  .hud-section:not(.hud-btn) { padding: 3px 6px; font-size: 12px; line-height: 1.3; }
  .hud-section.inventory { gap: 8px; }
  .inv-item { gap: 3px; }
  #hq-hp-display.low { color: var(--warning); }
  #hq-hp-display.crit { color: var(--danger); font-weight: bold; }

  #build-menu {
    gap: 5px;
    padding: 6px 6px calc(8px + env(safe-area-inset-bottom));
  }
  .build-btn {
    /* exactly 5 per row → 2 rows for 10 buttons */
    flex: 1 1 calc(20% - 5px);
    max-width: calc(20% - 5px);
    min-width: 0;
    padding: 10px 4px 8px;
  }
  .build-btn .label { display: none; }
  .build-btn .icon { font-size: 26px; line-height: 1.15; }
  .build-btn .cost { font-size: 11px; margin-top: 4px; color: var(--text); }
  .build-btn.disabled .cost { color: var(--text-dim); }

  #tool-hint { bottom: 130px; font-size: 12px; padding: 7px 14px; }
}

/* Smallest phones — keep 5-per-row but trim padding/icon */
@media (max-width: 380px) {
  .build-btn { padding: 8px 2px 6px; }
  .build-btn .icon { font-size: 22px; }
  .build-btn .cost { font-size: 10px; }
  #tool-hint { bottom: 116px; }
}