:root {
  --dos-blue: #0000AA;
  --dos-dark: #000080;
  --dos-black: #000000;
  --dos-white: #AAAAAA;
  --dos-bright-white: #FFFFFF;
  --dos-yellow: #FFFF55;
  --dos-cyan: #55FFFF;
  --dos-green: #55FF55;
  --dos-red: #FF5555;
  --dos-magenta: #FF55FF;
  --dos-gray: #555555;
}

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

body {
  background: var(--dos-black);
  font-family: 'VT323', monospace;
  color: var(--dos-bright-white);
  min-height: 100vh;
  overflow-x: hidden;
}

body::before {
  content: '';
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: repeating-linear-gradient(
    0deg,
    rgba(0,0,0,0.15) 0px,
    rgba(0,0,0,0.15) 1px,
    transparent 1px,
    transparent 3px
  );
  pointer-events: none;
  z-index: 9999;
}

@keyframes blink {
  0%, 50% { opacity: 1; }
  51%, 100% { opacity: 0; }
}

@keyframes crt-on {
  0% { transform: scaleY(0.005) scaleX(0.3); opacity: 0.5; }
  20% { transform: scaleY(0.005) scaleX(1); opacity: 0.7; }
  40% { transform: scaleY(1) scaleX(1); opacity: 1; filter: brightness(30); }
  60% { transform: scaleY(1) scaleX(1); opacity: 1; filter: brightness(1); }
  100% { transform: scaleY(1) scaleX(1); opacity: 1; filter: brightness(1); }
}

@keyframes compile-flash {
  0% { filter: brightness(1); }
  10% { filter: brightness(4) invert(1); }
  20% { filter: brightness(1); }
  100% { filter: brightness(1); }
}

.blink-cursor {
  animation: blink 1s step-end infinite;
}

.dos-panel {
  border: 2px solid var(--dos-white);
  background: var(--dos-blue);
  position: relative;
}

.dos-panel-double {
  border: none;
  background: var(--dos-blue);
  position: relative;
  padding: 2px;
}

.dos-panel-double::before {
  content: '';
  position: absolute;
  inset: 0;
  border: 3px double var(--dos-yellow);
  pointer-events: none;
  border-radius: 1px;
}

.dos-button {
  font-family: 'VT323', monospace;
  background: var(--dos-white);
  color: var(--dos-black);
  border: none;
  border-top: 2px solid var(--dos-bright-white);
  border-left: 2px solid var(--dos-bright-white);
  border-bottom: 2px solid var(--dos-gray);
  border-right: 2px solid var(--dos-gray);
  padding: 4px 16px;
  font-size: 18px;
  cursor: pointer;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.dos-button:hover {
  background: var(--dos-bright-white);
}

.dos-button:active {
  border-top: 2px solid var(--dos-gray);
  border-left: 2px solid var(--dos-gray);
  border-bottom: 2px solid var(--dos-bright-white);
  border-right: 2px solid var(--dos-bright-white);
}

.dos-button-primary {
  background: var(--dos-green);
  color: var(--dos-black);
  font-size: 22px;
  padding: 8px 24px;
  border-top: 3px solid #88FF88;
  border-left: 3px solid #88FF88;
  border-bottom: 3px solid #007700;
  border-right: 3px solid #007700;
}

.dos-button-primary:hover {
  background: #77EE77;
}

.drop-zone {
  border: 3px dashed var(--dos-yellow);
  background: rgba(0, 0, 170, 0.5);
  transition: all 0.2s;
  cursor: pointer;
  min-height: 180px;
}

.drop-zone.drag-over {
  background: rgba(85, 255, 85, 0.15);
  border-color: var(--dos-green);
}

.code-output {
  background: var(--dos-blue);
  color: var(--dos-yellow);
  font-family: 'VT323', monospace;
  font-size: 16px;
  line-height: 1.3;
  overflow: auto;
  white-space: pre;
  tab-size: 4;
}

.code-output::-webkit-scrollbar {
  width: 16px;
  height: 16px;
}

.code-output::-webkit-scrollbar-track {
  background: var(--dos-dark);
  border: 1px solid var(--dos-gray);
}

.code-output::-webkit-scrollbar-thumb {
  background: var(--dos-white);
  border: 1px solid var(--dos-gray);
}

.crt-bezel {
  background: #333;
  border-radius: 12px;
  padding: 12px;
  box-shadow:
    inset 0 0 30px rgba(0,0,0,0.5),
    0 0 10px rgba(0,0,0,0.8);
  position: relative;
}

.crt-bezel::after {
  content: '';
  position: absolute;
  inset: 12px;
  border-radius: 4px;
  box-shadow: inset 0 0 60px rgba(0,0,0,0.4);
  pointer-events: none;
}

.crt-screen {
  border-radius: 4px;
  overflow: hidden;
  position: relative;
  background: #000;
}

.crt-screen::after {
  content: '';
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    0deg,
    rgba(0,0,0,0.12) 0px,
    rgba(0,0,0,0.12) 1px,
    transparent 1px,
    transparent 2px
  );
  pointer-events: none;
}

.title-font {
  font-family: 'Press Start 2P', monospace;
}

.vt323 {
  font-family: 'VT323', monospace;
}

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  background: var(--dos-dark);
  height: 8px;
  border: 1px solid var(--dos-gray);
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px;
  height: 20px;
  background: var(--dos-white);
  border-top: 2px solid var(--dos-bright-white);
  border-left: 2px solid var(--dos-bright-white);
  border-bottom: 2px solid var(--dos-gray);
  border-right: 2px solid var(--dos-gray);
  cursor: pointer;
}

select {
  font-family: 'VT323', monospace;
  background: var(--dos-dark);
  color: var(--dos-bright-white);
  border: 1px inset var(--dos-gray);
  padding: 4px 8px;
  font-size: 18px;
}

.compile-anim {
  animation: compile-flash 0.5s ease-out;
}

.memory-warning {
  background: var(--dos-red);
  color: var(--dos-bright-white);
  border: 3px double var(--dos-yellow);
  padding: 12px;
  text-align: center;
  font-size: 20px;
}

.syntax-keyword { color: var(--dos-bright-white); }
.syntax-number { color: var(--dos-green); }
.syntax-string { color: var(--dos-magenta); }
.syntax-comment { color: var(--dos-gray); }
.syntax-paren { color: var(--dos-cyan); }