* {
  box-sizing: border-box;
}

body {
  margin: 0;
  color: var(--color-text);
  background: var(--color-canvas);
  font-family: 'Space Grotesk', sans-serif;
  font-size: 1rem;
  line-height: 1.6;
}

button,
input {
  font: inherit;
}

a {
  color: var(--color-info);
  text-underline-offset: 0.2em;
}

a,
button,
summary {
  -webkit-tap-highlight-color: transparent;
}

:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 4px;
}

[hidden] {
  display: none;
}

.app-shell {
  width: min(100% - 3rem, 48rem);
  margin-inline: auto;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-block: 2rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  flex-shrink: 0;
  max-width: 100%;
  min-height: 44px;
}

.brand picture,
.brand img {
  display: block;
  width: 132px;
  max-width: 100%;
  height: auto;
}

.source-link {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  padding-block: 0.5rem;
  font-size: var(--font-size-small);
}

main {
  min-width: 0;
}

.intro {
  margin-block: 1.5rem 2rem;
}

h1 {
  margin: 0;
  font-size: clamp(2rem, 6vw, 2.75rem);
  line-height: 1.15;
  letter-spacing: -0.04em;
}

.intro p {
  max-width: 40rem;
  margin-block: 0.75rem 0;
  color: var(--color-text-muted);
}

.intro .lead {
  font-size: var(--font-size-heading-small);
  font-weight: 500;
  color: var(--color-text);
}

.converter {
  padding: 1.5rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  min-width: 0;
}

.dropzone {
  display: flex;
  width: 100%;
  min-height: 13rem;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  border: 1px dashed var(--color-info-border);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  color: var(--color-text);
  background: var(--color-info-background);
  cursor: pointer;
  transition:
    background-color 160ms ease,
    border-color 160ms ease;
  overflow-wrap: anywhere;
}

.dropzone.drag {
  border-color: var(--color-info-accent);
  background: var(--color-surface-hover);
}

.dropzone:disabled {
  cursor: wait;
}

.upload-icon {
  margin-bottom: 0.5rem;
  color: var(--color-info);
  flex-shrink: 0;
  transition: transform 160ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.choose-label {
  font-weight: 600;
}

.drop-hint,
.supporting {
  font-size: var(--font-size-small);
  color: var(--color-text-muted);
}

.supporting {
  margin-block: 0.75rem;
}

.filename {
  font-size: var(--font-size-small);
  overflow-wrap: anywhere;
}

.filename:empty {
  display: none;
}

.status {
  padding: 1rem;
  margin-block: 1rem 0;
  border-radius: var(--radius-sm);
  background: var(--color-surface-muted);
  font-size: var(--font-size-small);
  overflow-wrap: anywhere;
}

.status[data-state='success'] {
  color: var(--color-success);
  background: var(--color-success-background);
}

.status[data-state='error'] {
  color: var(--color-error);
  background: var(--color-error-background);
}

progress {
  width: 100%;
  height: 0.5rem;
  margin-block: 1rem 0;
  accent-color: var(--color-info-accent);
}

.result {
  margin-top: 1rem;
}

.download-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0.625rem 1rem;
  background: var(--color-info-accent);
  color: white;
  border-radius: var(--radius-sm);
  text-decoration: none;
  font-weight: 500;
  overflow-wrap: anywhere;
}

.archive-contents {
  margin-top: 1rem;
  border-top: 1px solid var(--color-border);
  padding-top: 0.5rem;
}

summary {
  padding-block: 0.75rem;
  min-height: 44px;
  cursor: pointer;
  font-weight: 500;
  overflow-wrap: anywhere;
}

.archive-contents ul {
  list-style: none;
  padding: 0;
  margin-block: 0.5rem;
  max-height: 16rem;
  overflow-y: auto;
  font-size: var(--font-size-small);
}

.archive-contents li {
  padding-block: 0.5rem;
  border-top: 1px solid var(--color-border);
  overflow-wrap: anywhere;
}

.format-notes {
  margin-top: 1.5rem;
  font-size: var(--font-size-small);
}

.format-notes p {
  color: var(--color-text-muted);
  margin-block: 0 1rem;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-block: 2rem;
  font-size: var(--font-size-small);
  color: var(--color-text-muted);
}

.site-footer p {
  margin: 0;
}

.site-footer a {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
}

.visually-hidden,
.skip-link:not(:focus) {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.skip-link:focus {
  position: fixed;
  inset: 1rem auto auto 1rem;
  z-index: 1;
  padding: 0.5rem 1rem;
  background: var(--color-surface);
}

@media (hover: hover) and (pointer: fine) {
  .dropzone:hover {
    border-color: var(--color-info-accent);
    background: var(--color-surface-hover);
  }

  .dropzone:hover .upload-icon {
    transform: translateY(-2px);
  }
}

@media (width <= 30rem) {
  .app-shell {
    width: calc(100% - min(2rem, 8vw));
  }

  .site-header {
    padding-block: 1rem;
  }

  .intro {
    margin-top: 1rem;
  }

  .converter {
    padding: min(var(--space-4), 4vw);
  }

  .dropzone {
    padding: min(var(--space-4), 4vw);
  }

  .site-footer {
    flex-wrap: wrap;
    gap: 0.25rem 1rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .dropzone,
  .upload-icon {
    transition: none;
  }

  .dropzone:hover .upload-icon {
    transform: none;
  }
}

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;

    --color-canvas: #1f1c1d;
    --color-surface: #292526;
    --color-surface-muted: #353031;
    --color-surface-hover: #3c3537;
    --color-text: #f7f4f1;
    --color-text-muted: #cecaca;
    --color-border: #534b4d;
    --color-info: #bdcddd;
    --color-info-background: #26303d;
    --color-info-border: #697e9c;
    --color-success: #bfd9b8;
    --color-success-background: #243322;
    --color-error: #efc2bb;
    --color-error-background: #3f2926;
    --color-focus: #8bb3ff;
  }
}