/* PDF Signature Adder. Plain like PDF Redactor: system fonts, one ink-blue
   accent, the document as the largest thing on screen. The chrome follows the
   reader's light or dark setting; a PDF page stays white. Touch targets are at
   least --target (44 CSS px, Apple's guidance; PS-8). */
:root {
  --desk: #e7e9e4;
  --panel: #ffffff;
  --ink: #1f2731;
  --muted: #5b646d;
  --line: #c9cfc8;
  --accent: #24508a;
  --accent-ink: #ffffff;
  --alert: #a3341a;
  --select: #24508a;
  --shade: rgba(20, 26, 33, 0.5);
  --check-a: #ffffff;
  --check-b: #e6e8e3;
  --target: 44px;
  --gutter: 16px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --desk: #15191d;
    --panel: #1f252b;
    --ink: #e4e8ea;
    --muted: #a3adb4;
    --line: #3a434b;
    --accent: #8db4e6;
    --accent-ink: #0d1722;
    --alert: #f19a80;
    --select: #8db4e6;
    --shade: rgba(0, 0, 0, 0.6);
    --check-a: #2a3138;
    --check-b: #232a30;
    color-scheme: dark;
  }
}
* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--desk);
  color: var(--ink);
  font: 16px/1.45 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  touch-action: manipulation;
  padding-left: env(safe-area-inset-left, 0px);
  padding-right: env(safe-area-inset-right, 0px);
}
button {
  font: inherit;
  min-height: var(--target);
  min-width: var(--target);
  padding: 0 14px;
  border-radius: 6px;
  border: 1px solid var(--line);
  background: var(--panel);
  color: var(--ink);
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}
button.primary { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); font-weight: 600; }
button[aria-pressed="true"] { border: 2px solid var(--ink); font-weight: 600; }
button:disabled { opacity: 0.45; cursor: default; }
button:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; }
.group { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }

/* The bar */
#bar {
  position: sticky;
  top: 0;
  z-index: 5;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 16px;
  padding: max(10px, env(safe-area-inset-top, 0px)) var(--gutter) 10px;
  background: var(--panel);
  border-bottom: 1px solid var(--line);
}
body[data-screen="start"] #bar { display: none; }
.bar-file { display: flex; align-items: center; gap: 12px; min-width: 0; }
.file { display: grid; min-width: 0; }
.file strong { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; max-width: 34ch; }
.file span { color: var(--muted); font-size: 14px; }
.nav-label { min-width: 9ch; text-align: center; font-variant-numeric: tabular-nums; }
.status-bar { display: flex; flex-wrap: wrap; gap: 8px 12px; align-items: center; padding: 8px var(--gutter) 0; }
.status-bar p { margin: 0; color: var(--muted); }
body[data-placing="true"] .status-bar p { color: var(--ink); font-weight: 600; }
.message:not(:empty) { margin: 8px var(--gutter) 0; color: var(--alert); font-weight: 600; }
.note:not(:empty) { margin: 8px var(--gutter) 0; color: var(--muted); }
.message:empty, .note:empty { margin: 0; }

/* The start screen */
.start { max-width: 40rem; margin: 0 auto; padding: 12vh var(--gutter) 48px; display: grid; gap: 12px; }
.start h1 { margin: 0; font-size: clamp(30px, 5vw, 42px); line-height: 1.1; }
.start h2 { margin: 18px 0 0; font-size: 20px; }
.start p { margin: 0; }
.tagline { color: var(--muted); font-size: 18px; }
.privacy { color: var(--muted); font-size: 15px; }
.drop-hint { margin-top: 18px !important; padding: 26px; border: 2px dashed var(--line); border-radius: 8px; color: var(--muted); text-align: center; }
.start .group button { min-height: 52px; padding: 0 22px; font-size: 17px; }

/* Pages */
.pages { display: grid; justify-content: center; gap: 22px; padding: 18px var(--gutter) 64px; }
.page { display: grid; gap: 6px; justify-items: start; }
.page-label { margin: 0; font-size: 13px; font-weight: 600; color: var(--muted); letter-spacing: 0.02em; }
.paper {
  position: relative;
  background: #ffffff;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.18), 0 6px 18px rgba(0, 0, 0, 0.08);
  touch-action: pan-x pan-y pinch-zoom;
  user-select: none;
  -webkit-user-select: none;
  -webkit-touch-callout: none;
}
.paper canvas { position: absolute; inset: 0; width: 100%; height: 100%; }
body[data-placing="true"] .paper { cursor: crosshair; outline: 2px dashed var(--select); outline-offset: 3px; }
.layer { position: absolute; inset: 0; }
.overlay { position: absolute; touch-action: none; cursor: move; }
.overlay svg, .overlay img { display: block; width: 100%; height: 100%; }
.overlay.selected { outline: 2px dashed var(--select); outline-offset: 2px; }
.handle {
  position: absolute;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: #ffffff;
  border: 2.5px solid var(--select);
}
.handle.tl { left: -11px; top: -11px; cursor: nwse-resize; }
.handle.tr { right: -11px; top: -11px; cursor: nesw-resize; }
.handle.bl { left: -11px; bottom: -11px; cursor: nesw-resize; }
.handle.br { right: -11px; bottom: -11px; cursor: nwse-resize; }
.selection-actions {
  position: absolute;
  transform: translateY(calc(-100% - 14px));
  display: flex;
  gap: 0;
  background: #1f2731;
  border-radius: 8px;
  padding: 0 4px;
  white-space: nowrap;
}
.selection-actions button { background: transparent; border: 0; color: #ffffff; }

/* Dialogs */
.backdrop {
  position: fixed;
  inset: 0;
  z-index: 10;
  background: var(--shade);
  display: grid;
  place-items: center;
  padding: max(12px, env(safe-area-inset-top, 0px)) 12px max(12px, env(safe-area-inset-bottom, 0px));
  overflow-y: auto;
  overscroll-behavior: contain;
}
/* An open dialog locks the page behind it (T1). */
body[data-dialog="true"] { overflow: hidden; }
.dialog {
  width: min(900px, 100%);
  background: var(--panel);
  border-radius: 12px;
  padding: 20px clamp(16px, 3vw, 32px) 24px;
  display: grid;
  gap: 14px;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
}
.dialog h2 { margin: 0; font-size: 22px; }
.dialog-head { display: flex; justify-content: space-between; align-items: center; gap: 12px; }
.dialog-actions { justify-content: flex-end; border-top: 1px solid var(--line); padding-top: 14px; }
.dialog-actions button[data-action="signature.save_image"] { margin-right: auto; }
.tabs { background: var(--desk); padding: 4px; border-radius: 8px; justify-self: start; }
.tabs button { border: 0; background: transparent; }
.tabs button[aria-pressed="true"] { background: var(--panel); border: 1px solid var(--line); }
.row { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 12px; }
.row-label { color: var(--muted); font-size: 14px; min-width: 3ch; }
.hint { margin: 0; color: var(--muted); }

.pad-box { display: grid; gap: 6px; }
/* The box takes the pointer and refuses every touch gesture (T1); the SVG
   inside only draws. */
.pad-surface {
  touch-action: none;
  cursor: crosshair;
  user-select: none;
  -webkit-user-select: none;
  -webkit-touch-callout: none;
  -webkit-tap-highlight-color: transparent;
}
#pad {
  display: block;
  width: 100%;
  aspect-ratio: 3 / 1;
  background: #fbfbf8;
  border: 1px solid var(--line);
  border-radius: 8px;
  pointer-events: none;
}
#pad .baseline { stroke: #9aa39c; stroke-width: 3; stroke-dasharray: 6 14; }
.pad-hint { margin: 0; text-align: center; color: var(--muted); font-size: 14px; }

.preview {
  min-height: 180px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 12px;
  background-color: var(--check-a);
  background-image:
    linear-gradient(45deg, var(--check-b) 25%, transparent 25%),
    linear-gradient(-45deg, var(--check-b) 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, var(--check-b) 75%),
    linear-gradient(-45deg, transparent 75%, var(--check-b) 75%);
  background-size: 16px 16px;
  background-position: 0 0, 0 8px, 8px -8px, -8px 0;
}
.preview canvas { max-width: 100%; max-height: 260px; height: auto; }
.preview .empty { color: var(--muted); }
.source { margin: 0; color: var(--muted); font-size: 14px; }
.saved { width: min(560px, 100%); }
.saved-detail { margin: 0; font-weight: 600; overflow-wrap: anywhere; }

@media (max-width: 640px) {
  .file strong { max-width: 20ch; }
  .nav { order: 3; width: 100%; justify-content: center; }
}
@media (prefers-reduced-motion: reduce) {
  * { scroll-behavior: auto !important; }
}

/* The picture options are switches: say so with a box, not only a border. */
button[data-action^="picture."][aria-pressed]::before { content: "☐"; margin-right: 8px; font-weight: 400; }
button[data-action^="picture."][aria-pressed="true"]::before { content: "☑"; }