/* Linear/Things 3/Superhuman Design System */
/* Clean, minimal, fast, delightful */

:root {
  /* Colors - Dark mode first */
  --bg-primary: #0a0a0a;
  --bg-secondary: #141414;
  --bg-tertiary: #1a1a1a;
  --border: rgba(255, 255, 255, 0.1);
  --text-primary: #e5e5e5;
  --text-secondary: #a0a0a0;
  --text-tertiary: #6b6b6b;
  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --success: #10b981;
  --warning: #f59e0b;
  --error: #ef4444;
  
  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'SF Mono', 'Monaco', 'Cascadia Code', monospace;
  
  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  
  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* Base styles */
* {
  box-sizing: border-box;
}

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.2;
  margin: 0;
  color: var(--text-primary);
}

h1 { font-size: 2rem; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1rem; }

p {
  margin: 0;
  color: var(--text-secondary);
}

/* Buttons - Linear style */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: 0.5rem;
  border: none;
  cursor: pointer;
  transition: all var(--transition-base);
  font-family: var(--font-sans);
}

.btn-primary {
  background: var(--accent);
  color: white;
}

.btn-primary:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
}

.btn-ghost:hover {
  background: var(--bg-secondary);
  color: var(--text-primary);
}

/* Cards - Minimal, clean */
.card {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  padding: var(--space-lg);
  transition: all var(--transition-base);
}

.card:hover {
  border-color: rgba(255, 255, 255, 0.15);
  transform: translateY(-2px);
}

/* Inputs */
.input {
  width: 100%;
  padding: var(--space-sm) var(--space-md);
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  transition: all var(--transition-base);
}

.input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

/* Command Palette (Cmd+K) */
.command-palette {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 90%;
  max-width: 600px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.5);
  z-index: 1000;
  display: none;
}

.command-palette.active {
  display: block;
  animation: fadeIn 150ms ease-out;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translate(-50%, -48%);
  }
  to {
    opacity: 1;
    transform: translate(-50%, -50%);
  }
}

/* Skeleton loader (not spinner) */
.skeleton {
  background: linear-gradient(
    90deg,
    var(--bg-secondary) 0%,
    var(--bg-tertiary) 50%,
    var(--bg-secondary) 100%
  );
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite;
  border-radius: 0.5rem;
}

@keyframes shimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

/* Keyboard shortcut hint */
.kbd {
  display: inline-flex;
  align-items: center;
  padding: 0.125rem 0.375rem;
  font-size: 0.75rem;
  font-family: var(--font-mono);
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: 0.25rem;
  color: var(--text-secondary);
}

/* Smooth scroll */
html {
  scroll-behavior: smooth;
}

/* Focus visible (accessibility) */
*:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* Selection */
::selection {
  background: rgba(59, 130, 246, 0.3);
  color: var(--text-primary);
}