:root {
  color-scheme: light;
  --background: #ffffff;
  --foreground: #09090b;
  --card: #ffffff;
  --card-foreground: #09090b;
  --muted: #f4f4f5;
  --muted-foreground: #71717a;
  --border: #e4e4e7;
  --input: #e4e4e7;
  --primary: #18181b;
  --primary-foreground: #fafafa;
  --ring: #a1a1aa;
  --radius: 0.5rem;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.04);
}

* {
  box-sizing: border-box;
}

html {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--background);
  color: var(--foreground);
}

body {
  min-height: 100vh;
  margin: 0;
  display: flex;
  flex-direction: column;
  background: radial-gradient(circle at top, #fafafa 0, var(--background) 34rem);
}

a {
  color: inherit;
}

:focus-visible {
  outline: 2px solid var(--ring);
  outline-offset: 2px;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -4rem;
  z-index: 10;
  padding: 0.75rem 1rem;
  border-radius: var(--radius);
  background: var(--primary);
  color: var(--primary-foreground);
}

.skip-link:focus {
  top: 1rem;
}

.site-header {
  border-bottom: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.84);
  backdrop-filter: blur(14px);
}

.nav {
  width: min(1180px, calc(100% - 2rem));
  min-height: 4.5rem;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand,
.nav-links {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
}

.brand {
  font-weight: 800;
  text-decoration: none;
  letter-spacing: 0;
}

.brand-mark {
  width: 2rem;
  height: 2rem;
  display: grid;
  place-items: center;
  border-radius: calc(var(--radius) - 0.125rem);
  background: var(--primary);
  color: var(--primary-foreground);
  font-size: 0.9rem;
}

.nav-links a {
  text-decoration: none;
}

main {
  flex: 1;
}

.upload-view {
  width: min(620px, calc(100% - 2rem));
  min-height: calc(100vh - 9rem);
  margin: 0 auto;
  padding: 3rem 0;
  display: flex;
  align-items: center;
  justify-content: center;
}

h1 {
  margin: 0;
  color: var(--card-foreground);
  font-size: 1.8rem;
  line-height: 1.15;
  font-weight: 700;
}

.panel-header {
  display: grid;
  gap: 0.5rem;
  text-align: center;
}

.panel-header p {
  margin: 0;
  color: var(--muted-foreground);
  font-size: 0.95rem;
  line-height: 1.5;
}

.upload-panel {
  width: 100%;
  display: grid;
  gap: 1rem;
  padding: 1.25rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--card);
  box-shadow: var(--shadow);
}

.drop-zone {
  min-height: 17rem;
  display: grid;
  place-items: center;
  align-content: center;
  gap: 0.65rem;
  padding: 2rem;
  border: 1px dashed var(--input);
  border-radius: var(--radius);
  background: var(--muted);
  text-align: center;
  cursor: pointer;
  transition: border-color 160ms ease, background 160ms ease;
}

.drop-zone:hover,
.drop-zone.is-dragging {
  border-color: var(--primary);
  background: #fafafa;
}

.drop-zone input {
  position: absolute;
  inline-size: 1px;
  block-size: 1px;
  opacity: 0;
  pointer-events: none;
}

.drop-icon {
  width: 3rem;
  height: 3rem;
  display: grid;
  place-items: center;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--background);
  color: var(--foreground);
  font-size: 2rem;
  font-weight: 400;
}

.drop-title {
  font-size: 1rem;
  font-weight: 650;
}

.drop-copy {
  color: var(--muted-foreground);
  font-size: 0.9rem;
}

.advanced-options {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.8rem 0.9rem;
}

.advanced-options summary {
  color: var(--foreground);
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 650;
}

.option-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.9rem;
  margin-top: 1rem;
}

label span {
  display: block;
  margin-bottom: 0.35rem;
  color: var(--foreground);
  font-size: 0.85rem;
  font-weight: 600;
}

input,
select,
button {
  font: inherit;
}

input,
select {
  width: 100%;
  min-height: 2.25rem;
  border: 1px solid var(--input);
  border-radius: calc(var(--radius) - 0.125rem);
  padding: 0.6rem 0.75rem;
  background: var(--background);
  color: var(--foreground);
}

input::placeholder {
  color: var(--muted-foreground);
}

.form-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.form-footer p {
  margin: 0;
  color: var(--muted-foreground);
  font-size: 0.85rem;
}

.button,
button {
  min-height: 2.25rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid transparent;
  border-radius: calc(var(--radius) - 0.125rem);
  padding: 0.45rem 0.85rem;
  color: var(--foreground);
  background: transparent;
  font: inherit;
  font-size: 0.9rem;
  font-weight: 600;
  line-height: 1;
  cursor: pointer;
}

.button-primary {
  background: var(--primary);
  color: var(--primary-foreground);
}

.button-primary:hover {
  background: #27272a;
}

.button-outline {
  border-color: var(--border);
  background: var(--background);
}

.button-outline:hover,
.button-ghost:hover {
  background: var(--muted);
}

.site-footer {
  width: min(1180px, calc(100% - 2rem));
  margin: 0 auto;
  padding: 1.5rem 0;
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  color: var(--muted-foreground);
  font-size: 0.85rem;
}

@media (max-width: 840px) {
  .upload-view {
    min-height: calc(100vh - 9rem);
    padding: 2.5rem 0;
  }

  .option-grid,
  .form-footer,
  .site-footer {
    grid-template-columns: 1fr;
    flex-direction: column;
    align-items: stretch;
  }

  .drop-zone {
    min-height: 14rem;
  }
}