/* =====================================================================
   PDF BINNYASH — stylesheet
   Organized in sections: variables/base, nav + mobile menu, hero/home,
   generic page/panel/button primitives, tool-specific UI (merge, color,
   print layout, previews), modal/toast/loading, about/contact, and a
   responsive layer at the bottom for small screens.
   ===================================================================== */

:root {
  --bg: #f4f3ef;
  --fg: #171717;
  --muted: #686868;
  --line: #d8d5cf;
  --accent: #e97832;
  --panel: #fffdfa;
  --preview: #e9e7e2;
  --danger: #b23b35;
  --navh: 68px;          /* nav bar height — used for sticky offsets */
  --grid-line: #00000012; /* faint background grid line color */
}
* { box-sizing: border-box; }
html, body { min-height: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: Arial, Helvetica, sans-serif;
  min-height: 100vh;
  background-image:
    linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 28px 28px;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}
body.dark {
  --bg: #111211;
  --fg: #eee;
  --muted: #aaa;
  --line: #333;
  --panel: #191a18;
  --preview: #20211f;
  --danger: #e06a63;
  --grid-line: #ffffff10;
}

/* ---------------- NAV ---------------- */
nav {
  height: var(--navh);
  border-bottom: 1px solid var(--line);
  background: var(--bg);
  display: flex;
  align-items: center;
  padding: 0 28px;
  gap: 28px;
  position: sticky;
  top: 0;
  z-index: 30;
}
.logo { font-weight: 800; font-size: 20px; letter-spacing: -.5px; white-space: nowrap; }
.logo i { font-family: Georgia, serif; font-weight: 500; font-style: italic; }
#navlinks { display: flex; align-items: center; gap: 8px; flex: 1; }
nav a, nav button {
  color: var(--fg); text-decoration: none; background: none; border: 0;
  padding: 10px 13px; font-size: 14px; cursor: pointer; font-family: inherit;
}
nav a:hover, nav button:hover { color: var(--accent); }
.drop { position: relative; }
.drop > button { display: inline-flex; align-items: center; gap: 3px; }
.chev { display: inline-block; transition: transform .2s ease; font-size: 11px; }
.menu {
  display: none; position: absolute; top: 42px; left: 0; background: var(--panel);
  border: 1px solid var(--line); min-width: 205px; box-shadow: 0 12px 35px #0002; padding: 6px;
  border-radius: 8px;
}
.drop:hover .menu, .drop:focus-within .menu { display: block; }
.menu a { display: block; border-radius: 5px; }

/* Hamburger — animated bars -> X */
#hamb {
  display: none; position: relative; width: 38px; height: 38px; padding: 0;
  align-items: center; justify-content: center; border-radius: 8px;
}
#hamb:hover { background: color-mix(in srgb, var(--fg) 8%, transparent); color: var(--fg); }
.hamb-box { position: relative; display: block; width: 20px; height: 14px; }
.hamb-bar, .hamb-bar::before, .hamb-bar::after {
  content: ""; position: absolute; left: 0; width: 20px; height: 2px;
  background: var(--fg); border-radius: 2px;
  transition: transform .25s ease, opacity .2s ease, top .25s ease, background .2s ease;
}
.hamb-bar { top: 6px; }
.hamb-bar::before { top: -6px; }
.hamb-bar::after { top: 6px; }
#hamb.open .hamb-bar { background: transparent; }
#hamb.open .hamb-bar::before { transform: rotate(45deg); top: 0; background: var(--accent); }
#hamb.open .hamb-bar::after { transform: rotate(-45deg); top: 0; background: var(--accent); }

.nav-actions { display: flex; align-items: center; gap: 2px; }
.nav-action {
  font-size: 13px !important; padding: 8px 10px !important;
  border: 1px solid var(--line) !important; border-radius: 6px !important;
}
.nav-action:hover { border-color: var(--accent) !important; }
.na-short { display: none; }

/* ---------------- HOME / HERO ---------------- */
.hero { max-width: 900px; margin: 15vh auto; text-align: center; padding: 30px; }
.hero h1 { font-size: clamp(48px, 9vw, 112px); letter-spacing: clamp(-3px, -0.6vw, -5px); margin: 0; }
.hero h1 i { font-family: Georgia, serif; font-weight: 400; }
.squig { height: 18px; margin: 14px auto 28px; width: 220px; border-bottom: 4px solid var(--accent); border-radius: 50%; transform: rotate(-2deg); }
.hero p { max-width: 600px; margin: auto; color: var(--muted); font-size: clamp(15px, 3.6vw, 17px); line-height: 1.7; }
.hero p strong { color: var(--accent); font-weight: 700; }

.tools-overview { max-width: 980px; margin: 72px auto 0; text-align: left; }
.overview-heading { max-width: 680px; margin: 0 auto 24px; text-align: center; }
.overview-heading h2 { font-size: clamp(22px, 5.5vw, 30px); letter-spacing: -.6px; margin: 0 0 8px; }
.overview-heading p { font-size: 14px; line-height: 1.6; }
.tool-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.tool-card { background: var(--panel); border: 1px solid var(--line); border-radius: 12px; padding: 20px; min-height: 245px; transition: .15s transform, .15s border-color; }
.tool-card:hover { transform: translateY(-2px); border-color: var(--accent); }
.tool-card h3 { font-size: 17px; margin: 17px 0 7px; }
.tool-card p { font-size: 13px !important; line-height: 1.6 !important; margin: 0; color: var(--muted); }
.tool-visual { height: 82px; border: 1px solid var(--line); border-radius: 9px; background: var(--bg); position: relative; overflow: hidden; }
.merge-visual .sheet { position: absolute; width: 35px; height: 48px; border: 1px solid var(--line); background: var(--panel); top: 17px; border-radius: 3px; }
.merge-visual .sheet-a { left: 26px; transform: rotate(-8deg); }
.merge-visual .sheet-b { left: 47px; transform: rotate(6deg); }
.merge-visual .sheet-result { right: 27px; }
.merge-arrow { position: absolute; left: 50%; top: 31px; transform: translateX(-50%); color: var(--accent); font-size: 23px; }
.color-page { position: absolute; left: 28px; top: 14px; width: 40px; height: 54px; border: 1px solid var(--line); background: var(--panel); border-radius: 3px; }
.color-page:after { content: ""; position: absolute; left: 7px; right: 7px; top: 12px; height: 2px; background: var(--line); box-shadow: 0 9px 0 var(--line), 0 18px 0 var(--line); }
.color-slider { position: absolute; left: 88px; right: 23px; top: 40px; height: 2px; background: var(--line); }
.color-dot { position: absolute; width: 10px; height: 10px; border: 2px solid var(--accent); background: var(--panel); border-radius: 50%; left: 58%; top: 35px; }
.layout-visual { padding: 12px; display: grid; grid-template-columns: repeat(3, 1fr); grid-template-rows: repeat(2, 1fr); gap: 5px; }
.layout-visual span { display: block; border: 1px solid var(--line); background: var(--panel); border-radius: 2px; }
.sheet-size-readout { font-size: 12px; color: var(--muted); text-align: center; margin-top: 5px; font-variant-numeric: tabular-nums; }

/* ---------------- GENERIC PAGE / PANEL / BUTTONS ---------------- */
.page { max-width: 1120px; margin: 55px auto; padding: 0 28px; animation: fade .25s ease; }
.page h1 { font-size: clamp(30px, 6.5vw, 46px); margin-bottom: 8px; }
.sub { color: var(--muted); }
.panel { background: var(--panel); border: 1px solid var(--line); padding: 22px; border-radius: 12px; }
.actions { display: flex; gap: 10px; flex-wrap: wrap; margin: 18px 0; }
.actions.center { justify-content: center; }
.btn {
  border: 1px solid var(--line); background: var(--panel); color: var(--fg);
  padding: 11px 16px; border-radius: 7px; cursor: pointer; font-family: inherit;
  transition: .15s transform, .15s border-color, .15s background;
  min-height: 42px;
}
.btn:hover { transform: translateY(-1px); border-color: var(--accent); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: white; }
.btn.subtle { background: none; border-color: transparent; color: var(--muted); }
.btn.subtle:hover { color: var(--fg); border-color: var(--line); transform: none; }
.btn:disabled { opacity: .45; cursor: not-allowed; transform: none; }
.toggle.active { background: var(--accent); border-color: var(--accent); color: #fff; }

/* ---------------- MERGE ---------------- */
.dropzone { border: 1px dashed #aaa; padding: 34px; text-align: center; border-radius: 10px; transition: .2s; }
.dropzone.drag { border-color: var(--accent); background: #e9783210; }
.sort-actions { align-items: center; }
.sort-label { font-size: 13px; color: var(--muted); margin-right: 3px; }
.files { display: grid; grid-template-columns: repeat(auto-fill, minmax(190px, 1fr)); gap: 14px; margin-top: 18px; }
.file {
  position: relative; border: 1px solid var(--line); padding: 10px; background: var(--panel);
  cursor: grab; border-radius: 8px; transition: .15s border-color, .15s transform, .15s opacity;
}
.file:hover { border-color: var(--accent); }
.file.dragging { opacity: .45; }
.file.drag-target { border: 2px dashed var(--accent); transform: scale(.99); }
.drag-handle { position: absolute; right: 8px; top: 6px; z-index: 2; color: var(--muted); font-size: 18px; line-height: 1; letter-spacing: -3px; }
.file img { width: 100%; height: 170px; user-select: none; -webkit-user-drag: none; object-fit: contain; background: #eee; border-radius: 5px; display: block; }
.file .meta { display: flex; justify-content: space-between; align-items: center; gap: 8px; margin-top: 8px; font-size: 13px; flex-wrap: wrap; }
.file .meta span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.card-actions { display: flex; align-items: center; gap: 1px; flex-shrink: 0; }
.move-btn {
  font-size: 15px; padding: 4px 7px !important; border: 1px solid var(--line) !important;
  background: var(--panel) !important; border-radius: 5px !important; line-height: 1; min-width: 27px;
}
.move-btn:hover { border-color: var(--accent) !important; background: var(--bg) !important; }
.file small { color: var(--muted); display: block; margin-top: 6px; }
.icon-btn { border: 0; background: none; color: var(--fg); font-size: 22px; cursor: pointer; }
.empty { color: var(--muted); padding: 25px; text-align: center; grid-column: 1/-1; }
.error { color: var(--danger); font-size: 12px; }

/* ---------------- PREVIEWS (shared) ---------------- */
.preview {
  min-height: 390px; display: flex; align-items: center; justify-content: center;
  background: var(--preview); border: 1px solid var(--line); border-radius: 10px;
  overflow: hidden; position: relative;
}
.preview img { max-width: 100%; max-height: 610px; display: block; object-fit: contain; }
.color-preview { min-height: 560px; }
.color-preview img { max-height: 680px; width: auto; }
.layout-holder { min-height: 560px; padding: 24px; }
.layout-paper {
  width: 560px; height: 790px; aspect-ratio: 1/1.414; background: var(--panel);
  border: 1px solid var(--line); box-shadow: 0 8px 28px #0002;
  display: flex; align-items: stretch; justify-content: center; overflow: hidden;
}
.layout-paper img { width: 100%; height: 100%; display: block; object-fit: fill; image-rendering: auto; }
.preview-loading {
  display: none; position: absolute; inset: 0; align-items: center; justify-content: center;
  gap: 10px; background: #0005; color: white; font-size: 14px; backdrop-filter: blur(2px);
}
.preview-loading.show { display: flex; }
.mini-spinner { width: 24px; height: 24px; border: 3px solid #ffffff55; border-top-color: var(--accent); border-radius: 50%; animation: spin .7s linear infinite; }

/* Wraps a tool's preview + pager. Plain block on desktop; becomes a
   compact sticky panel on small screens (see responsive layer) so the
   preview stays visible while the controls below are scrolled. */
.sticky-preview { display: block; }

.pager { display: flex; justify-content: center; align-items: center; gap: 18px; margin: 15px; }
.controls { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 15px; margin-top: 18px; }
.control label { display: block; font-size: 13px; color: var(--muted); margin-bottom: 6px; }
.control label span { color: var(--fg); font-variant-numeric: tabular-nums; }
.control small { font-size: 11px; }
.control input, .control select {
  width: 100%; padding: 9px; background: var(--panel); color: var(--fg);
  border: 1px solid var(--line); border-radius: 6px; font-family: inherit;
  font-size: 16px; /* >=16px prevents iOS Safari from auto-zooming on focus */
}
.orientation-note { margin-top: 12px; color: var(--muted); font-size: 13px; }
.hint { color: var(--muted); font-size: 13px; line-height: 1.5; }

/* ---------------- MODAL / TOAST / LOADING ---------------- */
.modal { display: none; position: fixed; inset: 0; background: #0008; align-items: center; justify-content: center; z-index: 60; padding: 20px; }
.modalbox { background: var(--panel); padding: 30px; min-width: 350px; max-width: 440px; position: relative; border: 1px solid var(--line); border-radius: 12px; }
.toast {
  position: fixed; bottom: 24px; right: 24px; background: var(--fg); color: var(--bg);
  padding: 12px 16px; border-radius: 7px; z-index: 130; max-width: min(620px, 90vw); box-shadow: 0 10px 35px #0003;
}
.error-toast { background: var(--danger); color: #fff; }
.loading-overlay { position: fixed; inset: 0; background: #111b; display: none; align-items: center; justify-content: center; z-index: 100; backdrop-filter: blur(4px); }
.loading-overlay.show { display: flex; }
.loader-box { min-width: 290px; padding: 28px 34px; text-align: center; background: var(--panel); border: 1px solid var(--line); border-radius: 12px; box-shadow: 0 18px 60px #0005; }
.spinner { width: 34px; height: 34px; margin: 0 auto 16px; border: 3px solid var(--line); border-top-color: var(--accent); border-radius: 50%; animation: spin .75s linear infinite; }
.loading-text { font-weight: 700; }
.progress-track { height: 8px; background: var(--line); border-radius: 999px; overflow: hidden; margin: 16px 0 7px; }
.progress-bar { height: 100%; width: 0%; background: var(--accent); transition: width .12s ease; }
.progress-percent { font-size: 13px; font-variant-numeric: tabular-nums; font-weight: 700; }
.loading-small { font-size: 12px; color: var(--muted); margin-top: 7px; }

.empty-panel { text-align: center; padding: 60px; }
.prose { line-height: 1.75; }
@keyframes fade { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: none; } }
@keyframes spin { to { transform: rotate(360deg); } }

/* ---------------- ABOUT / FAQ / CONTACT ---------------- */
.faq-section { margin-top: 38px; border-top: 1px solid var(--line); padding-top: 26px; }
.faq-section h2, .contact-panel h2 { font-size: clamp(20px, 5vw, 25px); margin: 0 0 14px; }
.faq-item { border-top: 1px solid var(--line); }
.faq-item:last-of-type { border-bottom: 1px solid var(--line); }
.faq-item summary { cursor: pointer; list-style: none; padding: 15px 4px; font-weight: 600; font-size: 14px; position: relative; padding-right: 30px; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary:after { content: "+"; position: absolute; right: 4px; color: var(--muted); font-size: 18px; font-weight: 400; top: 12px; }
.faq-item[open] summary:after { content: "−"; }
.faq-answer { padding: 0 4px 16px; color: var(--muted); font-size: 14px; line-height: 1.7; }
.section-subtitle { color: var(--muted); font-style: italic; margin-top: -2px; }

.contact-links { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; margin-top: 18px; }
.contact-link {
  display: grid; grid-template-columns: 32px 1fr; grid-template-rows: auto auto; column-gap: 12px;
  align-items: center; border: 1px solid var(--line); border-radius: 9px; padding: 13px 14px;
  text-decoration: none; color: var(--fg); transition: .15s border-color, .15s transform;
  min-height: 44px;
}
.contact-link:hover { border-color: var(--accent); transform: translateY(-1px); }
.contact-logo { width: 24px; height: 24px; grid-row: 1 / 3; color: var(--accent); }
.contact-link span { font-size: 14px; font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.contact-link small { color: var(--muted); font-size: 11px; margin-top: 3px; line-height: 1.35; }

.support-content { text-align: center; }
.support-title { font-weight: 700; font-size: clamp(24px, 6vw, 35px); margin: 4px 0 7px; }
.support-small { font-size: 15px; line-height: 1.55; color: var(--muted); margin: 0 auto; max-width: 430px; }
.support-actions { margin-top: 22px; flex-direction: column; align-items: stretch; }
.support-actions .btn { width: 100%; }

/* =====================================================================
   RESPONSIVE — small screens
   ===================================================================== */
@media (max-width: 800px) {
  .tool-cards { grid-template-columns: 1fr; }
  .contact-links { grid-template-columns: 1fr; }
  .tools-overview { margin-top: 55px; }
}

@media (max-width: 700px) {
  :root { --grid-line: #00000016; }
  body.dark { --grid-line: #ffffff12; }

  nav { padding: 0 14px; gap: 6px; }
  .logo { flex: 1; font-size: clamp(16px, 4.6vw, 20px); }
  .nav-actions { gap: 2px; }
  .nav-action { padding: 9px 10px !important; }
  #hamb { display: inline-flex; order: 2; }
  #theme { order: 3; padding: 9px 10px; }

  /* Compact floating dropdown instead of a full-bleed panel */
  #navlinks {
    display: flex; flex-direction: column; align-items: stretch; gap: 2px;
    position: absolute; top: calc(var(--navh) + 8px); left: 10px; right: 10px;
    background: var(--panel); border: 1px solid var(--line); border-radius: 14px;
    box-shadow: 0 18px 45px #0003; padding: 8px;
    max-height: 0; opacity: 0; overflow: hidden; pointer-events: none;
    transform: translateY(-6px) scale(.98); transform-origin: top center;
    transition: max-height .28s cubic-bezier(.4,0,.2,1), opacity .18s ease, transform .22s cubic-bezier(.4,0,.2,1);
  }
  #navlinks.open {
    max-height: 75vh; opacity: 1; pointer-events: auto;
    transform: translateY(0) scale(1); overflow-y: auto;
  }
  #navlinks a, #navlinks .drop > button {
    padding: 13px 14px; border-radius: 9px; font-size: 15px; text-align: left; width: 100%;
    min-height: 44px; display: flex; align-items: center; justify-content: space-between;
  }
  #navlinks a:hover, #navlinks .drop > button:hover { background: var(--bg); color: var(--fg); }
  .drop .menu {
    display: block; position: static; border: 0; box-shadow: none; padding: 0 0 0 8px; margin: 0;
    max-height: 0; opacity: 0; overflow: hidden;
    transition: max-height .22s ease, opacity .18s ease, margin .22s ease;
  }
  .drop.open .menu { max-height: 220px; opacity: 1; margin-top: 2px; margin-bottom: 4px; }
  .drop.open > button .chev { transform: rotate(180deg); }
  .drop .menu a { padding: 11px 12px; font-size: 14px; }

  .hero { margin: 10vh auto; }
  .hero h1 { letter-spacing: -3px; }
  .page { margin: 30px auto; padding: 0 15px; }
  .panel { padding: 16px; }

  .modalbox { min-width: 0; width: 92%; padding: 24px 20px; }

  /* Sticky compact previews so calibration/layout controls can be
     scrolled without losing sight of the PDF preview. */
  .sticky-preview {
    position: sticky; top: var(--navh); z-index: 6;
    background: var(--bg); padding: 8px 0 6px; margin: 0 0 8px;
    box-shadow: 0 12px 16px -12px #0000004d;
  }
  body.dark .sticky-preview { box-shadow: 0 12px 16px -12px #00000099; }
  .sticky-preview .preview { min-height: unset; border-radius: 8px; }
  .sticky-preview .color-preview { max-height: 34vh; }
  .sticky-preview .color-preview img { max-height: 32vh; }
  .sticky-preview .layout-holder { max-height: 34vh; padding: 8px; }
  .sticky-preview .layout-paper { max-height: 30vh; }
  .sticky-preview .pager { margin: 8px 0 2px; gap: 14px; }
  .sticky-preview .pager .btn { min-width: 44px; }

  .controls { grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 12px; }
  .sort-label { width: 100%; }

  .files { grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 10px; }
  .file img { height: 140px; }
  .file .meta { font-size: 12px; }
  .icon-btn { font-size: 24px; padding: 4px; }

  .btn { padding: 12px 16px; }
  .support-actions { margin-top: 18px; }
}

@media (max-width: 480px) {
  .files { grid-template-columns: repeat(auto-fill, minmax(130px, 1fr)); }
  .tool-visual { height: 70px; }
  .pager span { font-size: 13px; }
}

@media (max-width: 380px) {
  .nav-action { font-size: 0 !important; padding: 9px !important; min-width: 38px; }
  #back::before { content: "←"; font-size: 15px; }
  #reload::before { content: "⟳"; font-size: 16px; }
}