:root {
  /* Paper & ink palette */
  --paper: #fafafa;
  --paper-dark: #f0f0f0;
  --ink: #1a1817;
  --ink-light: #4a4745;
  --ink-faded: #8a8785;
  --accent: #c23c2a;
  --accent-hover: #a32f1f;

  /* Typography */
  --font-display: 'Libre Franklin', system-ui, sans-serif;
  --font-serif: 'Instrument Serif', Georgia, serif;
  --font-mono: 'JetBrains Mono', monospace;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2.5rem;
  --space-2xl: 4rem;

  /* Borders */
  --border: 1.5px solid var(--ink);
  --border-light: 1px solid var(--ink-faded);
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-display);
  font-weight: 400;
  background: var(--paper);
  color: var(--ink);
  min-height: 100vh;
  line-height: 1.5;
}

/* Paper grain overlay */
.grain {
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.25;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
  z-index: 9999;
}

/* Layout */
.layout {
  max-width: 900px;
  margin: 0 auto;
  padding: var(--space-xl) var(--space-lg);
  display: grid;
  gap: var(--space-xl);
}

@media (min-width: 768px) {
  .layout {
    padding: var(--space-2xl);
    grid-template-columns: 1fr 280px;
    grid-template-areas:
      "header header"
      "dropzone options"
      "files options"
      "progress progress"
      "results results"
      "viewer viewer"
      "footer footer";
  }

  .header { grid-area: header; }
  .dropzone-wrapper { grid-area: dropzone; }
  .options-panel { grid-area: options; }
  .file-list { grid-area: files; }
  .progress-section { grid-area: progress; }
  .results-section { grid-area: results; }
  .viewer-section { grid-area: viewer; }
  .footer { grid-area: footer; }
}

/* Header */
.header {
  text-align: center;
  padding-bottom: var(--space-lg);
  border-bottom: var(--border);
}

.logo {
  font-family: var(--font-display);
  font-size: clamp(2.5rem, 8vw, 4rem);
  font-weight: 900;
  letter-spacing: -0.03em;
  line-height: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
}

.logo-cbz {
  color: var(--ink-light);
}

.logo-arrow {
  font-weight: 400;
  color: var(--accent);
}

.logo-xtc {
  color: var(--ink);
}

.tagline {
  margin-top: var(--space-sm);
  font-size: 0.9rem;
  color: var(--ink-faded);
  letter-spacing: 0.02em;
}

.tagline em {
  font-family: var(--font-serif);
  font-style: italic;
  color: var(--ink-light);
}

/* Section headers */
.section-header {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
}

.section-header h2 {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--ink-faded);
}

.badge {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  background: var(--ink);
  color: var(--paper);
  padding: 0.15em 0.5em;
  border-radius: 2px;
}

/* Footer */
.footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: var(--space-lg);
  border-top: var(--border-light);
  font-size: 0.8rem;
  color: var(--ink-faded);
}

.footer a {
  color: var(--ink-light);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s;
}

.footer a:hover {
  border-color: var(--ink-light);
}

/* Utility */
.hidden {
  display: none !important;
}

/* Selection */
::selection {
  background: var(--ink);
  color: var(--paper);
}