/* ==========================================================================
   LM3915 Dual VU Meter Calibration Bench - 1960s Laboratory Design System
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Fira+Code:wght@400;600&family=Inter:wght@400;600;700&family=Orbitron:wght@500;700;900&family=Share+Tech+Mono&display=swap');

:root {
  /* Color Palette - 1960s Instrument Console */
  --chassis-bg: #1c2024;
  --chassis-dark: #121518;
  --chassis-metal: #2a3038;
  --panel-slate: #242b33;
  --panel-border: #3b4552;
  --panel-inset: #161a1e;
  
  --bezel-aluminum: linear-gradient(135deg, #8b939c 0%, #4a525d 50%, #2e353f 100%);
  --knob-bakelite: radial-gradient(circle at 35% 35%, #383a3d 0%, #1a1b1d 60%, #0d0e0f 100%);
  --brass-accent: #c5a059;
  
  /* Phosphor Colors */
  --p31-green: #00ff66;
  --p31-glow: rgba(0, 255, 102, 0.4);
  --p7-amber: #ffb000;
  --p7-glow: rgba(255, 176, 0, 0.4);
  --crt-bg: #050e09;
  --crt-graticule: rgba(0, 255, 102, 0.18);
  
  /* LED Colors */
  --led-green-off: #0b2414;
  --led-green-on: #00ff44;
  --led-green-glow: rgba(0, 255, 68, 0.6);
  
  --led-yellow-off: #2c2507;
  --led-yellow-on: #ffcc00;
  --led-yellow-glow: rgba(255, 204, 0, 0.6);
  
  --led-red-off: #2b0b0b;
  --led-red-on: #ff2233;
  --led-red-glow: rgba(255, 34, 51, 0.7);

  /* Indicator Jewels */
  --jewel-red-off: #3d0505;
  --jewel-red-on: #ff1122;
  --jewel-red-glow: 0 0 15px #ff1122, 0 0 30px rgba(255, 17, 34, 0.6);
  
  /* Typography */
  --font-mono: 'Share Tech Mono', 'Fira Code', monospace;
  --font-display: 'Orbitron', sans-serif;
  --font-sans: 'Inter', sans-serif;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  user-select: none;
  -webkit-user-select: none;
}

body {
  background-color: #0d0f12;
  background-image: 
    radial-gradient(circle at 50% 20%, #1e242c 0%, #0d0f12 80%),
    repeating-linear-gradient(0deg, rgba(255, 255, 255, 0.01) 0px, rgba(255, 255, 255, 0.01) 1px, transparent 1px, transparent 3px);
  color: #d1d9e6;
  font-family: var(--font-sans);
  min-height: 100vh;
  padding: 20px;
  display: flex;
  justify-content: center;
  align-items: center;
}

/* ==========================================================================
   Main Chassis & Frame
   ========================================================================== */

.bench-chassis {
  width: 100%;
  max-width: 1280px;
  background: var(--panel-slate);
  border: 4px solid #101215;
  border-radius: 12px;
  box-shadow: 
    0 20px 50px rgba(0, 0, 0, 0.8),
    inset 0 1px 1px rgba(255, 255, 255, 0.15),
    inset 0 -2px 5px rgba(0, 0, 0, 0.5);
  position: relative;
  overflow: hidden;
  padding: 24px;
}

/* Rack Handles & Machined Corner Screws */
.chassis-corner-screw {
  position: absolute;
  width: 14px;
  height: 14px;
  background: radial-gradient(circle, #6b7582 30%, #303742 70%);
  border-radius: 50%;
  box-shadow: inset 0 1px 2px rgba(255,255,255,0.4), 0 2px 4px rgba(0,0,0,0.6);
}
.chassis-corner-screw::before {
  content: '';
  position: absolute;
  top: 6px;
  left: 2px;
  width: 10px;
  height: 2px;
  background: #1a1e24;
  transform: rotate(35deg);
}

.screw-tl { top: 12px; left: 12px; }
.screw-tr { top: 12px; right: 12px; }
.screw-bl { bottom: 12px; left: 12px; }
.screw-br { bottom: 12px; right: 12px; }

/* Chassis Header Bar */
.chassis-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-bottom: 16px;
  margin-bottom: 20px;
  border-bottom: 2px solid var(--panel-border);
  background: linear-gradient(180deg, rgba(255,255,255,0.03) 0%, transparent 100%);
}

.brand-badge {
  display: flex;
  align-items: center;
  gap: 16px;
}

.model-plate {
  background: linear-gradient(135deg, #1c2024 0%, #0d0f12 100%);
  border: 2px solid var(--brass-accent);
  border-radius: 4px;
  padding: 6px 14px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.5);
}

.model-title {
  font-family: var(--font-display);
  font-size: 1.1rem;
  letter-spacing: 2px;
  color: #f0f4f8;
  text-transform: uppercase;
}

.model-subtitle {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--brass-accent);
  letter-spacing: 1px;
}

/* Jewel Power Pilot Lamp */
.power-assembly {
  display: flex;
  align-items: center;
  gap: 18px;
}

.jewel-lamp-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.jewel-lamp {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: radial-gradient(circle at 35% 35%, #7a1414 0%, var(--jewel-red-off) 70%);
  border: 2px solid #5a6370;
  box-shadow: inset 0 2px 4px rgba(0,0,0,0.8), 0 2px 5px rgba(0,0,0,0.5);
  transition: all 0.3s ease;
  position: relative;
}

.jewel-lamp::after {
  content: '';
  position: absolute;
  top: 3px;
  left: 4px;
  width: 7px;
  height: 5px;
  background: rgba(255, 255, 255, 0.4);
  border-radius: 50%;
  transform: rotate(-30deg);
}

.jewel-lamp.active {
  background: radial-gradient(circle at 35% 35%, #ffaabb 0%, var(--jewel-red-on) 60%, #880000 100%);
  box-shadow: var(--jewel-red-glow), inset 0 1px 2px rgba(255,255,255,0.8);
}

.jewel-label {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 1px;
  color: #8b95a5;
  text-transform: uppercase;
}

/* Power Toggle Switch */
.toggle-switch-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  cursor: pointer;
}

.toggle-switch {
  width: 44px;
  height: 68px;
  background: #14171a;
  border: 2px solid #3d4652;
  border-radius: 6px;
  position: relative;
  box-shadow: inset 0 2px 6px rgba(0,0,0,0.8);
  display: flex;
  justify-content: center;
  align-items: center;
}

.bat-handle {
  width: 14px;
  height: 34px;
  background: linear-gradient(90deg, #606873 0%, #d8e0ea 40%, #7d8794 80%, #3e444c 100%);
  border-radius: 7px;
  box-shadow: 0 4px 8px rgba(0,0,0,0.6);
  transition: transform 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  transform: translateY(12px);
}

.toggle-switch-container.active .bat-handle {
  transform: translateY(-12px);
}

/* ==========================================================================
   Main Bench Layout Grid
   ========================================================================== */

.bench-grid {
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: 20px;
}

@media (max-width: 960px) {
  .bench-grid {
    grid-template-columns: 1fr;
  }
}

/* Instrument Module Containers */
.instrument-panel {
  background: var(--panel-inset);
  border: 2px solid var(--panel-border);
  border-radius: 8px;
  padding: 16px;
  box-shadow: inset 0 2px 8px rgba(0,0,0,0.7), 0 1px 0 rgba(255,255,255,0.05);
  display: flex;
  flex-direction: column;
  gap: 14px;
  position: relative;
}

.panel-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  padding-bottom: 8px;
}

.panel-title {
  font-family: var(--font-display);
  font-size: 0.85rem;
  letter-spacing: 1.5px;
  color: var(--brass-accent);
  text-transform: uppercase;
  display: flex;
  align-items: center;
  gap: 8px;
}

.panel-title i {
  font-style: normal;
  color: #6b788a;
}

/* ==========================================================================
   1960s CRT Oscilloscope Display
   ========================================================================== */

.crt-bezel-outer {
  background: linear-gradient(145deg, #1b2026 0%, #0c0e10 100%);
  border: 4px solid #2e3640;
  border-radius: 16px;
  padding: 12px;
  box-shadow: 
    inset 0 4px 10px rgba(0,0,0,0.9),
    0 4px 12px rgba(0,0,0,0.5);
  position: relative;
}

.crt-screen-container {
  width: 100%;
  height: 280px;
  background-color: var(--crt-bg);
  border-radius: 12px;
  position: relative;
  overflow: hidden;
  box-shadow: inset 0 0 30px rgba(0, 0, 0, 0.95);
  border: 2px solid #122218;
}

/* Glass Refraction & Scanlines Overlay */
.crt-glass-glare {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  background: 
    linear-gradient(135deg, rgba(255, 255, 255, 0.06) 0%, rgba(255, 255, 255, 0) 50%),
    repeating-linear-gradient(0deg, rgba(0, 0, 0, 0.25) 0px, rgba(0, 0, 0, 0.25) 1px, transparent 1px, transparent 2px);
  border-radius: 10px;
  z-index: 10;
}

canvas#scopeCanvas {
  width: 100%;
  height: 100%;
  display: block;
}

/* CRT Scope Control Sub-Panel */
.scope-controls {
  display: flex;
  justify-content: space-around;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  padding-top: 6px;
}

/* ==========================================================================
   Bakelite Rotary Knobs System
   ========================================================================== */

.knob-control-group {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
}

.knob-outer {
  width: 58px;
  height: 58px;
  border-radius: 50%;
  background: #111417;
  border: 2px solid #3c4654;
  box-shadow: 0 4px 8px rgba(0,0,0,0.6), inset 0 1px 2px rgba(255,255,255,0.1);
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
  cursor: grab;
}

.knob-outer:active {
  cursor: grabbing;
}

.knob-dial {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--knob-bakelite);
  border: 1px solid #485260;
  position: relative;
  box-shadow: inset 0 0 8px rgba(0,0,0,0.9);
  transition: transform 0.05s linear;
}

/* Fluted ridges on bakelite knob */
.knob-dial::before {
  content: '';
  position: absolute;
  top: 4px;
  left: 4px;
  right: 4px;
  bottom: 4px;
  border-radius: 50%;
  border: 1px dashed rgba(255,255,255,0.12);
}

.knob-pointer {
  position: absolute;
  top: 5px;
  left: 50%;
  transform: translateX(-50%);
  width: 3px;
  height: 16px;
  background: #f0f4f8;
  border-radius: 2px;
  box-shadow: 0 0 4px rgba(255,255,255,0.8);
}

.knob-label {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.8px;
  color: #a0acbd;
  text-transform: uppercase;
  text-align: center;
}

.knob-value-badge {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--p31-green);
  background: #0d1115;
  border: 1px solid #232b35;
  padding: 2px 6px;
  border-radius: 3px;
}

/* Small Knob Variant */
.knob-control-group.small .knob-outer {
  width: 44px;
  height: 44px;
}
.knob-control-group.small .knob-dial {
  width: 36px;
  height: 36px;
}
.knob-control-group.small .knob-pointer {
  height: 12px;
  width: 2px;
}

/* Mode Buttons Pill Group */
.mode-btn-group {
  display: flex;
  gap: 4px;
  background: #101418;
  padding: 4px;
  border-radius: 6px;
  border: 1px solid var(--panel-border);
}

.mode-btn {
  background: #1a2026;
  border: 1px solid #333d4a;
  color: #8c98a8;
  padding: 5px 9px;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  cursor: pointer;
  transition: all 0.15s ease;
}

.mode-btn.active {
  background: #2b3846;
  color: var(--p31-green);
  border-color: var(--p31-green);
}

/* ==========================================================================
   Audio Tone Generator Module
   ========================================================================== */

.waveform-selector {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 6px;
  background: #111417;
  padding: 4px;
  border-radius: 6px;
  border: 1px solid var(--panel-border);
}

.wave-btn {
  background: #1a2026;
  border: 1px solid #333d4a;
  color: #8c98a8;
  padding: 6px 4px;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  transition: all 0.2s ease;
}

.wave-btn svg {
  width: 18px;
  height: 12px;
  stroke: currentColor;
  fill: none;
  stroke-width: 2;
}

.wave-btn:hover {
  background: #27303a;
  color: #d8e2ee;
}

.wave-btn.active {
  background: #2e3a47;
  color: var(--p31-green);
  border-color: var(--p31-green);
  box-shadow: 0 0 8px var(--p31-glow);
}

.generator-controls-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

/* Frequency Calibration Presets */
.preset-pills {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.preset-pill {
  background: #13181e;
  border: 1px solid #2e3745;
  color: #9cb0c7;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 4px 8px;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.15s ease;
}

.preset-pill:hover, .preset-pill.active {
  background: #25313f;
  color: var(--p7-amber);
  border-color: var(--p7-amber);
}

/* Auto Sweep Button */
.sweep-toggle-btn {
  background: linear-gradient(180deg, #2b3542 0%, #171d24 100%);
  border: 1px solid #4a5666;
  color: #e0e8f2;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 8px 14px;
  border-radius: 4px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.4);
}

.sweep-toggle-btn.active {
  background: linear-gradient(180deg, #8a2020 0%, #521010 100%);
  border-color: #ff3344;
  color: #fff;
  box-shadow: 0 0 10px rgba(255, 51, 68, 0.5);
}

/* Input Source Toggle */
.source-toggle-btn {
  background: #141b22;
  border: 1px solid #334050;
  color: #a0b2c6;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  padding: 4px 8px;
  border-radius: 4px;
  cursor: pointer;
}
.source-toggle-btn.mic {
  background: #291e0a;
  border-color: var(--p7-amber);
  color: var(--p7-amber);
}

/* ==========================================================================
   Master Level & Illuminated Bat Switches (SOLO / MUTE)
   ========================================================================== */

.master-routing-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.channel-switches-group {
  display: flex;
  gap: 16px;
  background: #101418;
  padding: 10px;
  border-radius: 6px;
  border: 1px solid var(--panel-border);
}

.channel-column {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.ch-title {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: #7d8b9e;
}

.bat-btn {
  width: 48px;
  height: 28px;
  border-radius: 4px;
  border: 1px solid #3a4554;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: bold;
  cursor: pointer;
  display: flex;
  justify-content: center;
  align-items: center;
  transition: all 0.2s ease;
  background: #1a2026;
  color: #647285;
}

.bat-btn.solo.active {
  background: #005522;
  color: #00ff66;
  border-color: #00ff66;
  box-shadow: 0 0 10px rgba(0, 255, 102, 0.5);
}

.bat-btn.mute.active {
  background: #660011;
  color: #ff3344;
  border-color: #ff3344;
  box-shadow: 0 0 10px rgba(255, 51, 68, 0.5);
}

/* DC Detector Pod */
.dc-detector-pod {
  background: #0b0e11;
  border: 1px solid #252e38;
  border-radius: 6px;
  padding: 8px 12px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.pod-title {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  color: #6e7d91;
  text-transform: uppercase;
}

.pod-value {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--p7-amber);
}

/* ==========================================================================
   9-Band Frequency Graphic EQ
   ========================================================================== */

.eq-bank-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: #101317;
  padding: 14px 10px;
  border-radius: 6px;
  border: 1px solid var(--panel-border);
  overflow-x: auto;
}

.eq-slider-col {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  height: 150px;
  min-width: 32px;
}

.eq-slider-track {
  height: 100px;
  width: 6px;
  background: #1c232c;
  border-radius: 3px;
  position: relative;
  display: flex;
  justify-content: center;
}

.eq-slider-thumb {
  width: 22px;
  height: 12px;
  background: linear-gradient(180deg, #707b8c 0%, #303742 100%);
  border: 1px solid #94a1b3;
  border-radius: 2px;
  position: absolute;
  left: 50%;
  transform: translate(-50%, 0);
  box-shadow: 0 2px 4px rgba(0,0,0,0.6);
  cursor: pointer;
}

.eq-slider-thumb::after {
  content: '';
  position: absolute;
  top: 5px;
  left: 2px;
  right: 2px;
  height: 2px;
  background: var(--brass-accent);
}

.eq-freq-label {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  color: #8090a3;
}

.eq-db-label {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  color: var(--p31-green);
}

.btn-flat-eq {
  background: #1c242e;
  border: 1px solid #384556;
  color: #a8b8cc;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  padding: 4px 10px;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.15s ease;
}

.btn-flat-eq:hover {
  background: #2d3b4b;
  color: #fff;
}

/* ==========================================================================
   LM3915 Dual VU LED Meter Emulation
   ========================================================================== */

.meters-dual-container {
  display: flex;
  justify-content: space-around;
  background: #0b0e11;
  padding: 16px;
  border-radius: 8px;
  border: 2px solid #232b35;
}

.meter-channel {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
}

.meter-title {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 1px;
  color: #92a2b5;
}

.led-bar-ladder {
  display: flex;
  flex-direction: column-reverse;
  gap: 5px;
  background: #07090b;
  padding: 10px 14px;
  border-radius: 6px;
  border: 1px solid #1a222a;
}

.led-segment {
  width: 48px;
  height: 12px;
  border-radius: 2px;
  border: 1px solid rgba(0,0,0,0.6);
  position: relative;
  transition: background-color 0.05s ease, box-shadow 0.05s ease;
}

/* Green LEDs (1 to 6) */
.led-segment.green {
  background-color: var(--led-green-off);
}
.led-segment.green.active {
  background-color: var(--led-green-on);
  box-shadow: 0 0 10px var(--led-green-glow);
}

/* Yellow LEDs (7 to 8) */
.led-segment.yellow {
  background-color: var(--led-yellow-off);
}
.led-segment.yellow.active {
  background-color: var(--led-yellow-on);
  box-shadow: 0 0 10px var(--led-yellow-glow);
}

/* Red LEDs (9 to 10) */
.led-segment.red {
  background-color: var(--led-red-off);
}
.led-segment.red.active {
  background-color: var(--led-red-on);
  box-shadow: 0 0 12px var(--led-red-glow);
}

.meter-readout-pod {
  background: #12171d;
  border: 1px solid #2c3745;
  border-radius: 4px;
  padding: 4px 8px;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--p31-green);
  width: 100%;
}

/* Mode Switch: Bar vs Dot */
.meter-mode-toggle {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: #8c9cb0;
}

/* ==========================================================================
   Reference Table & Drawer Modal
   ========================================================================== */

.drawer-toggle-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 16px;
  background: #181f26;
  border: 1px solid var(--panel-border);
  padding: 10px 16px;
  border-radius: 6px;
  cursor: pointer;
}

.drawer-toggle-title {
  font-family: var(--font-display);
  font-size: 0.8rem;
  color: var(--brass-accent);
  letter-spacing: 1px;
}

.guide-drawer-content {
  display: none;
  background: #11151a;
  border: 1px solid var(--panel-border);
  border-radius: 6px;
  padding: 16px;
  margin-top: 10px;
  font-family: var(--font-sans);
  font-size: 0.82rem;
  line-height: 1.5;
  color: #b0bfd1;
}

.guide-drawer-content.open {
  display: block;
}

.ref-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
}

.ref-table th, .ref-table td {
  border: 1px solid #28323e;
  padding: 6px 10px;
  text-align: left;
}

.ref-table th {
  background: #1a222b;
  color: var(--brass-accent);
}

.ref-table tr:nth-child(even) {
  background: #151b22;
}

.badge-green { color: var(--led-green-on); }
.badge-yellow { color: var(--led-yellow-on); }
.badge-red { color: var(--led-red-on); }

/* Interactive Trimmer Simulator */
.trimmer-sim-box {
  background: #171d24;
  border: 1px dashed var(--brass-accent);
  padding: 12px;
  border-radius: 6px;
  margin-top: 14px;
}

.trimmer-sim-header {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--brass-accent);
  margin-bottom: 8px;
}