/* 
 * Beat Maker CSS - Inspired by Dieter Rams' Design Principles
 * Following the "Less, but better" philosophy with clean, minimal design
 */

/* Font imports */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600&display=swap');

/* CSS Reset and Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  /* Color Palette inspired by Braun products and Dieter Rams' work */
  --color-bg: #F8F8F8;
  --color-surface: #FFFFFF;
  --color-text: #222222;
  --color-text-secondary: #666666;
  --color-border: #E1E4E1;
  --color-accent: #ED8008;
  --color-active: #ED3F1C;
  --color-inactive: #E0E0E0;
  --color-hover: #F0F0F0;
  --color-step-active: #ED3F1C;
  --color-step-border: #E1E4E1;
  
  /* Spacing - following mathematical precision */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  
  /* Typography */
  --font-family: 'Inter', 'Helvetica Neue', 'SF Pro', 'Segoe UI', Arial, sans-serif;
  --font-size-sm: 0.875rem;
  --font-size-md: 1rem;
  --font-size-lg: 1.25rem;
  --font-size-xl: 1.75rem;
  
  /* Borders and Shadows */
  --border-radius-sm: 2px;
  --border-radius-md: 4px;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 2px 4px rgba(0, 0, 0, 0.1);
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-md);
  line-height: 1.5;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-lg);
}

/* Header Styles */
.header {
  margin-bottom: var(--spacing-lg);
  padding-bottom: var(--spacing-md);
  border-bottom: 1px solid var(--color-border);
}

h1 {
  font-size: var(--font-size-xl);
  font-weight: 500;
  letter-spacing: -0.02em;
  color: var(--color-text);
}

/* Control Panel Styles */
.control-panel {
  margin-bottom: var(--spacing-lg);
  padding: var(--spacing-md);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-md);
  box-shadow: var(--shadow-sm);
}

.transport-controls {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

/* Button Styles - Inspired by Braun product controls */
.control-btn {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
  position: relative;
}

.control-btn:hover {
  background-color: var(--color-hover);
}

.control-btn:active, .control-btn.active {
  background-color: var(--color-accent);
}

/* Play button with triangle icon */
#play-button::before {
  content: '';
  display: block;
  width: 0;
  height: 0;
  border-top: 8px solid transparent;
  border-bottom: 8px solid transparent;
  border-left: 12px solid var(--color-text);
  margin-left: 2px;
}

#play-button.active::before {
  border-left-color: white;
}

/* Pause button with two lines */
#pause-button::before,
#pause-button::after {
  content: '';
  display: block;
  width: 3px;
  height: 14px;
  background-color: var(--color-text);
  position: absolute;
}

#pause-button::before {
  left: 14px;
}

#pause-button::after {
  right: 14px;
}

#pause-button.active::before,
#pause-button.active::after {
  background-color: white;
}

/* Tempo Control Styles */
.tempo-control {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  margin-left: auto;
}

.tempo-control label {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

input[type="range"] {
  -webkit-appearance: none;
  width: 150px;
  height: 2px;
  background: var(--color-border);
  outline: none;
  border-radius: var(--border-radius-sm);
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--color-accent);
  cursor: pointer;
}

input[type="range"]::-moz-range-thumb {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--color-accent);
  cursor: pointer;
  border: none;
}

#tempo-value {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  min-width: 70px;
}

/* Beat Grid Styles */
.beat-grid {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-md);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}

/* Track Labels */
.track-labels {
  display: flex;
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding: var(--spacing-sm) 0;
}

.track-labels .track-label {
  padding: var(--spacing-sm) var(--spacing-md);
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--color-text-secondary);
}

.track-labels .track-label:first-child {
  width: 150px;
  flex-shrink: 0;
}

.track-labels .track-label:nth-child(2) {
  width: 120px;
  flex-shrink: 0;
}

/* Track Styles */
.track {
  display: flex;
  border-bottom: 1px solid var(--color-border);
}

.track:last-child {
  border-bottom: none;
}

.track-info {
  width: 270px;
  padding: var(--spacing-sm);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  background-color: var(--color-bg);
  border-right: 1px solid var(--color-border);
  flex-shrink: 0;
}

.track-name {
  width: 100px;
  font-size: var(--font-size-sm);
  color: var(--color-text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* Mute and Solo buttons */
.mute-btn, .solo-btn {
  width: 24px;
  height: 24px;
  border-radius: var(--border-radius-sm);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-sm);
  transition: all 0.2s ease;
}

.mute-btn::before {
  content: 'M';
  color: var(--color-text-secondary);
}

.solo-btn::before {
  content: 'S';
  color: var(--color-text-secondary);
}

.mute-btn:hover, .solo-btn:hover {
  background-color: var(--color-hover);
}

.mute-btn.active {
  background-color: var(--color-active);
}

.mute-btn.active::before {
  color: white;
}

.solo-btn.active {
  background-color: var(--color-accent);
}

.solo-btn.active::before {
  color: white;
}

/* Volume slider */
.volume-slider {
  width: 60px;
}

/* Beat Pads Container */
.beat-pads {
  flex: 1;
  display: flex;
  padding: var(--spacing-sm);
  gap: var(--spacing-xs);
}

/* Beat Pad - will be generated via JavaScript */
.beat-pad {
  flex: 1;
  height: 30px;
  background-color: var(--color-inactive);
  border-radius: var(--border-radius-sm);
  cursor: pointer;
  transition: background-color 0.2s ease;
}

.beat-pad:hover {
  background-color: var(--color-hover);
}

.beat-pad.active {
  background-color: var(--color-accent);
}

.beat-pad.current {
  box-shadow: 0 0 0 2px rgba(0, 0, 0, 0.2);
}

/* Every 4th beat pad for visual rhythm */
.beat-pad:nth-child(4n+1) {
  background-color: #E8E8E8;
}

.beat-pad.active:nth-child(4n+1) {
  background-color: var(--color-accent);
}

/* Footer Styles */
.footer {
  margin-top: var(--spacing-lg);
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--color-border);
  text-align: center;
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

/* Responsive Design */
@media (max-width: 768px) {
  .container {
    padding: var(--spacing-md);
  }
  
  .transport-controls {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--spacing-md);
  }
  
  .tempo-control {
    margin-left: 0;
    width: 100%;
    flex-wrap: wrap;
  }
  
  .track-info {
    width: 180px;
  }
  
  .track-name {
    width: 70px;
  }
  
  .beat-pads {
    overflow-x: auto;
  }
}

/* For smaller screens */
@media (max-width: 480px) {
  .track-info {
    width: 120px;
  }
  
  .track-name {
    width: 50px;
  }
  
  .mute-btn, .solo-btn {
    width: 20px;
    height: 20px;
  }
}

/* Utility Classes */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}