:root {
  color-scheme: light;
  --bg: #f5f5f7;
  --surface: rgba(255, 255, 255, .86);
  --surface-solid: #fff;
  --ink: #1d1d1f;
  --muted: #6e6e73;
  --line: rgba(0, 0, 0, .09);
  --blue: #0071e3;
  --blue-hover: #0077ed;
  --green: #2aa876;
  --danger: #c9342f;
  --shadow: 0 18px 55px rgba(0, 0, 0, .08);
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { min-width: 320px; background: var(--bg); }
body {
  min-height: 100vh;
  margin: 0;
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  background:
    radial-gradient(circle at 12% -15%, rgba(0, 113, 227, .10), transparent 32rem),
    var(--bg);
}
button, input, textarea { font: inherit; }
button { color: inherit; }

.app-shell { width: min(1220px, calc(100% - 40px)); margin: 0 auto; padding: 18px 0 34px; }

.workspace { display: grid; grid-template-columns: minmax(0, 1fr) 330px; gap: 16px; align-items: start; }
.viewer-card, .settings-card {
  border: 1px solid var(--line);
  border-radius: 22px;
  background: var(--surface);
  box-shadow: var(--shadow);
  backdrop-filter: blur(20px);
}
.viewer-card { overflow: hidden; }
.upload-zone { display: grid; min-height: 250px; padding: 30px 24px; place-items: center; align-content: center; text-align: center; cursor: pointer; transition: background .18s ease; }
.upload-zone:hover, .upload-zone:focus-visible, .upload-zone.is-over { outline: none; background: rgba(0, 113, 227, .035); }
.upload-icon { display: grid; width: 50px; height: 50px; margin-bottom: 14px; place-items: center; border-radius: 15px; color: var(--blue); background: #eaf4ff; }
.upload-icon svg { width: 25px; fill: none; stroke: currentColor; stroke-width: 1.65; stroke-linecap: round; stroke-linejoin: round; }
.upload-zone h2 { margin: 0; font-size: 20px; letter-spacing: -.025em; }
.upload-zone p { margin: 6px 0 16px; color: var(--muted); font-size: 13px; }
.choose-button { min-height: 40px; padding: 0 18px; border: 0; border-radius: 999px; color: #fff; background: var(--blue); font-weight: 600; cursor: pointer; }
.choose-button:hover { background: var(--blue-hover); }

.preview-area { min-height: 654px; }
.file-bar { display: flex; min-height: 68px; align-items: center; justify-content: space-between; gap: 16px; padding: 13px 18px; border-bottom: 1px solid var(--line); }
.file-copy { min-width: 0; }
.file-copy strong, .file-copy span { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.file-copy strong { font-size: 14px; }
.file-copy span { margin-top: 3px; color: var(--muted); font-size: 12px; }
.text-button { flex: 0 0 auto; border: 0; color: var(--blue); background: transparent; font-size: 13px; cursor: pointer; }
.text-button.danger { color: var(--danger); }
.page-stage { position: relative; display: grid; height: 530px; padding: 24px; place-items: center; overflow: auto; background: #e9e9ed; }
.paper { position: relative; overflow: hidden; background: white; box-shadow: 0 12px 35px rgba(0, 0, 0, .16); }
.paper canvas { display: block; max-width: 100%; height: auto; }
#watermarkCanvas { position: absolute; inset: 0; }
.loading { position: absolute; padding: 9px 13px; border-radius: 10px; color: var(--muted); background: rgba(255, 255, 255, .9); font-size: 13px; box-shadow: 0 5px 18px rgba(0,0,0,.08); }
.page-nav { display: flex; min-height: 55px; align-items: center; justify-content: center; gap: 15px; border-top: 1px solid var(--line); color: var(--muted); font-size: 13px; }
.page-nav button { display: grid; width: 30px; height: 30px; place-items: center; border: 1px solid var(--line); border-radius: 50%; background: #fff; font-size: 22px; line-height: 1; cursor: pointer; }
.page-nav button:disabled { opacity: .32; cursor: default; }

.settings-card { overflow: hidden; }
.settings-section { padding: 16px; }
.settings-section + .settings-section, .metadata { border-top: 1px solid var(--line); }
.section-heading { display: flex; align-items: flex-start; justify-content: space-between; gap: 10px; margin-bottom: 11px; }
.section-heading span { color: var(--muted); font-size: 11px; font-weight: 650; }
.section-heading h2 { margin: 2px 0 0; font-size: 17px; letter-spacing: -.02em; }
.fixed-angle { padding: 5px 8px; border-radius: 7px; background: #f0f0f3; }
.preset-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 7px; }
.preset-card { position: relative; display: grid; min-height: 72px; padding: 7px; place-items: center; overflow: hidden; border: 1px solid var(--line); border-radius: 11px; background: #fff; cursor: pointer; }
.preset-card:hover { border-color: rgba(0, 113, 227, .42); }
.preset-card.is-selected { border-color: var(--blue); box-shadow: 0 0 0 2px rgba(0, 113, 227, .13); }
.preset-card img { width: 100%; height: 35px; object-fit: contain; }
.preset-card span { width: 100%; overflow: hidden; color: var(--muted); font-size: 11px; text-align: center; text-overflow: ellipsis; white-space: nowrap; }
.preset-placeholder { grid-column: 1 / -1; padding: 18px; color: var(--muted); font-size: 13px; text-align: center; }
.preset-pager { display: flex; align-items: center; justify-content: center; gap: 9px; margin-top: 8px; color: var(--muted); font-size: 11px; font-variant-numeric: tabular-nums; }
.preset-pager button { display: grid; width: 26px; height: 26px; place-items: center; border: 1px solid var(--line); border-radius: 50%; background: #fff; font-size: 18px; line-height: 1; cursor: pointer; }
.preset-pager button:disabled { opacity: .3; cursor: default; }

.controls { display: grid; gap: 12px; }
.control-row { display: grid; grid-template-columns: 1fr auto; gap: 8px; align-items: center; font-size: 13px; font-weight: 600; }
.control-row output { color: var(--muted); font-variant-numeric: tabular-nums; }
.control-row input { grid-column: 1 / -1; width: 100%; accent-color: var(--blue); }
.segmented { display: grid; grid-template-columns: 1fr 1fr; padding: 3px; border-radius: 10px; background: #ededf0; }
.segmented button { min-height: 32px; border: 0; border-radius: 8px; background: transparent; color: var(--muted); font-size: 12px; font-weight: 600; cursor: pointer; }
.segmented button.is-active { color: var(--ink); background: #fff; box-shadow: 0 2px 8px rgba(0,0,0,.08); }

.metadata { padding: 0 16px; }
.metadata summary { padding: 14px 0; font-size: 13px; font-weight: 650; cursor: pointer; }
.metadata-fields { display: grid; gap: 12px; padding: 0 0 20px; }
.metadata-fields label { display: grid; gap: 6px; color: var(--muted); font-size: 11px; font-weight: 600; }
.metadata-fields input, .metadata-fields textarea { width: 100%; border: 1px solid var(--line); border-radius: 10px; outline: none; color: var(--ink); background: #fff; font-size: 13px; font-weight: 400; }
.metadata-fields input { height: 38px; padding: 0 11px; }
.metadata-fields textarea { padding: 9px 11px; resize: vertical; }
.metadata-fields input:focus, .metadata-fields textarea:focus { border-color: var(--blue); box-shadow: 0 0 0 3px rgba(0, 113, 227, .11); }
.save-defaults { justify-self: start; border: 0; color: var(--blue); background: transparent; padding: 0; font-size: 12px; font-weight: 600; cursor: pointer; }
.field-note { margin: -3px 0 0; color: var(--muted); font-size: 11px; line-height: 1.5; }

.export-dock { position: fixed; z-index: 30; right: max(18px, calc((100vw - 1220px) / 2)); bottom: 18px; display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 8px 14px; width: min(430px, calc(100vw - 36px)); padding: 12px 14px; border: 1px solid rgba(0, 0, 0, .1); border-radius: 16px; background: rgba(255, 255, 255, .92); box-shadow: 0 14px 36px rgba(0, 0, 0, .16); backdrop-filter: saturate(180%) blur(20px); }
.output-name { min-width: 0; align-self: center; }
.output-name span, .output-name strong { display: block; }
.output-name span { color: var(--muted); font-size: 11px; }
.output-name strong { margin-top: 4px; overflow: hidden; font-size: 13px; text-overflow: ellipsis; white-space: nowrap; }
.primary-button { display: flex; min-width: 142px; min-height: 42px; align-items: center; justify-content: center; gap: 8px; border: 0; border-radius: 11px; color: #fff; background: var(--blue); font-weight: 650; cursor: pointer; }
.primary-button:hover { background: var(--blue-hover); }
.primary-button:disabled { opacity: .38; cursor: default; }
.primary-button svg { width: 18px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.status { grid-column: 1 / -1; min-height: 0; margin: -4px 0 0; color: var(--muted); font-size: 11px; line-height: 1.35; }
.status.is-error { color: var(--danger); }
.status.is-success { color: #1d7b55; }

.background-note { margin: 12px 2px 0; color: #929299; font-size: 11px; line-height: 1.5; }
.background-note.has-signature { color: var(--danger); font-weight: 600; }

@media (max-width: 960px) {
  .workspace { grid-template-columns: 1fr; }
  .settings-card { display: grid; grid-template-columns: 1fr 1fr; }
  .settings-section + .settings-section { border-top: 0; border-left: 1px solid var(--line); }
  .metadata { grid-column: 1 / -1; }
}

@media (max-width: 640px) {
  .app-shell { width: min(100% - 22px, 1280px); padding: 12px 0 26px; }
  .viewer-card { border-radius: 18px; }
  .upload-zone { min-height: 220px; }
  .preview-area { min-height: 508px; }
  .page-stage { height: 385px; padding: 15px; }
  .settings-card { display: block; border-radius: 18px; }
  .settings-section + .settings-section { border-top: 1px solid var(--line); border-left: 0; }
  .export-dock { right: 11px; bottom: 11px; width: calc(100% - 22px); }
}

@media (prefers-reduced-motion: reduce) {
  * { scroll-behavior: auto !important; transition: none !important; }
}