:root {
  --color-bg: #f6f7f9;
  --color-surface: #ffffff;
  --color-surface-muted: #eef2f6;
  --color-text: #172033;
  --color-text-muted: #667085;
  --color-border: #d8dee8;
  --color-primary: #1f5eff;
  --color-primary-hover: #174bd0;
  --color-danger: #b42318;
  --color-danger-bg: #fff1f0;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: SFMono-Regular, Consolas, monospace;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-6: 24px;
  --space-8: 32px;
  --radius: 12px;
  --radius-sm: 8px;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }

body {
  margin: 0;
  min-height: 100dvh;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-sans);
}

.shell { width: min(1440px, 100%); margin: 0 auto; padding: var(--space-6); }
.card { background: var(--color-surface); border: 1px solid var(--color-border); border-radius: var(--radius); }
.login-card { max-width: 420px; margin: 12vh auto; padding: var(--space-8); }
.stack { display: grid; gap: var(--space-4); }
.muted { color: var(--color-text-muted); font-size: var(--text-sm); }
.eyebrow { margin: 0 0 var(--space-2); color: var(--color-primary); font: 700 var(--text-sm) var(--font-mono); text-transform: uppercase; }
h1, h2 { margin: 0; line-height: 1.2; }
h1 { font-size: clamp(1.5rem, 3vw, 2rem); }
h2 { font-size: var(--text-xl); }

label { display: grid; gap: var(--space-2); font-weight: 650; }
input {
  width: 100%; padding: var(--space-3) var(--space-4); border: 1px solid var(--color-border);
  border-radius: var(--radius-sm); font: inherit; color: var(--color-text); background: var(--color-surface);
}
button, .button-link {
  display: inline-flex; align-items: center; justify-content: center; min-height: 42px;
  padding: 0 var(--space-4); border: 1px solid var(--color-primary); border-radius: var(--radius-sm);
  background: var(--color-primary); color: #fff; font: 700 var(--text-base) var(--font-sans);
  text-decoration: none; cursor: pointer; transition: background-color 160ms ease, border-color 160ms ease, transform 160ms ease;
}
button:hover, .button-link:hover { background: var(--color-primary-hover); border-color: var(--color-primary-hover); }
button:focus-visible, .button-link:focus-visible, input:focus-visible, .drop-zone:focus-visible, .icon-btn:focus-visible { outline: 3px solid color-mix(in srgb, var(--color-primary), transparent 65%); outline-offset: 2px; }
button:disabled { opacity: 0.65; cursor: not-allowed; }
.secondary { background: var(--color-surface); color: var(--color-primary); }
.secondary:hover { background: var(--color-surface-muted); color: var(--color-primary-hover); }

.topbar { display: flex; align-items: center; justify-content: space-between; gap: var(--space-4); margin-bottom: var(--space-6); }
.upload-card { padding: var(--space-6); }
.drop-zone { display: grid; justify-items: center; gap: var(--space-4); padding: var(--space-8); border: 2px dashed var(--color-border); border-radius: var(--radius); text-align: center; background: var(--color-surface-muted); }
.drop-zone.drag-over { border-color: var(--color-primary); background: #e9efff; }
.progress { display: flex; align-items: center; gap: var(--space-3); margin-top: var(--space-4); color: var(--color-text-muted); }
.spinner { width: 20px; height: 20px; border: 3px solid var(--color-border); border-top-color: var(--color-primary); border-radius: 50%; animation: spin 900ms linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

.result-toolbar { display: flex; align-items: center; justify-content: space-between; gap: var(--space-4); margin-bottom: var(--space-6); flex-wrap: wrap; }
.nav-controls { display: flex; align-items: center; gap: var(--space-2); }
.nav-info { font-weight: 650; font-size: var(--text-base); min-width: 160px; text-align: center; }
.icon-btn { display: inline-flex; align-items: center; justify-content: center; width: 36px; height: 36px; padding: 0; border: 1px solid var(--color-border); border-radius: var(--radius-sm); background: var(--color-surface); color: var(--color-text); font-size: 1.25rem; font-weight: 700; cursor: pointer; transition: background-color 160ms ease, border-color 160ms ease; }
.icon-btn:hover:not(:disabled) { background: var(--color-surface-muted); border-color: var(--color-primary); color: var(--color-primary); }
.icon-btn:disabled { opacity: 0.4; cursor: not-allowed; }
.zoom-controls { display: flex; align-items: center; gap: var(--space-2); }
.zoom-level { font-size: var(--text-sm); font-weight: 650; min-width: 48px; text-align: center; color: var(--color-text-muted); }

.result-grid { display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(360px, 0.85fr); gap: var(--space-6); }
.pdf-card, .fields-card { min-height: 70vh; padding: var(--space-4); }
.panel-head { display: flex; align-items: center; justify-content: space-between; gap: var(--space-3); margin-bottom: var(--space-4); }
.pdf-viewer { display: grid; gap: var(--space-4); max-height: 72vh; overflow: auto; padding: var(--space-3); background: var(--color-surface-muted); border-radius: var(--radius-sm); }
.pdf-viewer canvas { width: 100%; height: auto; border: 1px solid var(--color-border); background: #fff; }
.fields-list { display: grid; gap: var(--space-3); margin: 0; }
.field { padding: var(--space-3); border: 1px solid var(--color-border); border-radius: var(--radius-sm); background: var(--color-surface); }
.field dt { margin-bottom: var(--space-2); color: var(--color-text-muted); font-size: var(--text-sm); font-weight: 700; }
.field dd { margin: 0; line-height: 1.45; }
.field ul { margin: 0; padding-left: var(--space-6); }
.error-banner { margin-bottom: var(--space-4); padding: var(--space-4); border: 1px solid #fecdca; border-radius: var(--radius-sm); background: var(--color-danger-bg); color: var(--color-danger); }
.error-banner pre { white-space: pre-wrap; max-height: 220px; overflow: auto; font-family: var(--font-mono); }
.error-text { color: var(--color-danger); }

@media (max-width: 860px) {
  .shell { padding: var(--space-4); }
  .topbar { align-items: flex-start; flex-direction: column; }
  .result-grid { grid-template-columns: 1fr; }
  .pdf-card, .fields-card { min-height: auto; }
  .pdf-viewer { max-height: 65vh; }
  .result-toolbar { flex-direction: column; align-items: stretch; }
}