/* ============================================================
   PDFToolsHub — Shared Stylesheet
   Responsive | Ad-friendly | Fast | SEO clean
   ============================================================ */
:root{
  --brand:#2563eb;
  --brand-dark:#1e40af;
  --brand-soft:#eff6ff;
  --accent:#f97316;
  --ink:#0f172a;
  --muted:#64748b;
  --line:#e2e8f0;
  --bg:#f8fafc;
  --card:#ffffff;
  --radius:14px;
  --shadow:0 1px 3px rgba(15,23,42,.08),0 8px 24px rgba(15,23,42,.06);
  --shadow-lg:0 10px 40px rgba(15,23,42,.14);
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  background:var(--bg);color:var(--ink);line-height:1.6;
  display:flex;flex-direction:column;min-height:100vh;
  -webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;
}
a{color:var(--brand);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;display:block}
.container{width:100%;max-width:1100px;margin:0 auto;padding:0 18px}
main{flex:1;padding:28px 0 48px}

/* ---------- Header ---------- */
.site-header{background:var(--card);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:50}
.nav{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:14px 0;flex-wrap:wrap}
.brand{display:flex;align-items:center;gap:10px;font-weight:800;font-size:1.2rem;color:var(--ink)}
.brand .logo{width:38px;height:38px;background:linear-gradient(135deg,var(--brand),var(--brand-dark));border-radius:10px;display:grid;place-items:center;color:#fff;font-size:1.1rem}
.brand span b{color:var(--brand)}
.nav-links{display:flex;gap:6px;flex-wrap:wrap}
.nav-links a{color:var(--muted);font-weight:600;font-size:.92rem;padding:8px 12px;border-radius:8px}
.nav-links a:hover{background:var(--brand-soft);color:var(--brand);text-decoration:none}
.menu-toggle{display:none;background:none;border:1px solid var(--line);border-radius:8px;font-size:1.4rem;padding:4px 10px;cursor:pointer}

/* ---------- Hero ---------- */
.hero{text-align:center;padding:34px 0 10px}
.hero h1{font-size:clamp(1.6rem,4vw,2.6rem);line-height:1.2;letter-spacing:-.02em;margin-bottom:12px}
.hero h1 span{background:linear-gradient(90deg,var(--brand),var(--accent));-webkit-background-clip:text;background-clip:text;color:transparent}
.hero p{color:var(--muted);font-size:clamp(1rem,2.2vw,1.15rem);max-width:640px;margin:0 auto 8px}

/* ---------- Cards grid ---------- */
.tool-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:16px;margin-top:22px}
.tool-card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:20px 18px;transition:transform .15s,box-shadow .15s;color:var(--ink)}
.tool-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);text-decoration:none}
.tool-card .icon{width:46px;height:46px;border-radius:12px;display:grid;place-items:center;font-size:1.4rem;margin-bottom:14px;color:#fff}
.tool-card h3{font-size:1.02rem;margin-bottom:6px}
.tool-card p{font-size:.85rem;color:var(--muted);margin:0}
.c-merge{background:#4f46e5}.c-split{background:#0891b2}.c-remove{background:#dc2626}
.c-organize{background:#7c3aed}.c-rotate{background:#d97706}.c-crop{background:#059669}
.c-imgpdf{background:#c026d3}.c-pdfimg{background:#e11d48}.c-number{background:#2563eb}
.c-water{background:#0d9488}.c-unlock{background:#16a34a}.c-protect{background:#374151}
.c-compress{background:#b45309}.c-md{background:#334155}.c-sign{background:#9333ea}

/* ---------- Tool page ---------- */
.tool-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:26px;align-items:start;margin-top:8px}
.tool-body{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:22px}
.breadcrumb{font-size:.85rem;color:var(--muted);margin-bottom:14px}
.breadcrumb a{color:var(--brand)}
.tool-body h1{font-size:clamp(1.4rem,3vw,2rem);letter-spacing:-.02em;margin-bottom:8px}
.tool-sub{color:var(--muted);margin-bottom:20px;font-size:.95rem}
.dropzone{border:2px dashed #cbd5e1;border-radius:12px;padding:34px 18px;text-align:center;cursor:pointer;transition:.15s;background:var(--bg);display:block;position:relative;overflow:hidden}
/* Bulletproof mobile upload: the real <input type=file> is stretched as a
   transparent overlay covering the whole dropzone. Tapping ANYWHERE hits the
   actual input element directly — this opens the native picker on iOS,
   Android and desktop without relying on JS click(), label forwarding or role. */
.dz-input{position:absolute;top:0;left:0;width:100%;height:100%;opacity:0;cursor:pointer;z-index:3;margin:0;padding:0;border:0}
.dropzone > :not(.dz-input){pointer-events:none}
.dropzone:hover,.dropzone.drag{border-color:var(--brand);background:var(--brand-soft)}
.dropzone .dz-icon{font-size:2.6rem;margin-bottom:10px}
.dropzone p{color:var(--muted);font-size:.92rem}
.dropzone p b{color:var(--ink)}
.file-list{margin-top:16px}
.file-item{display:flex;align-items:center;gap:12px;background:var(--bg);border:1px solid var(--line);border-radius:10px;padding:10px 14px;margin-bottom:8px}
.file-item .fi-icon{font-size:1.3rem}
.file-item .fi-name{flex:1;font-weight:600;font-size:.9rem;word-break:break-all}
.file-item .fi-size{color:var(--muted);font-size:.78rem;white-space:nowrap}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;background:var(--brand);color:#fff;border:none;border-radius:10px;padding:12px 22px;font-size:1rem;font-weight:700;cursor:pointer;transition:.15s}
.btn:hover{background:var(--brand-dark);text-decoration:none}
.btn:disabled{opacity:.5;cursor:not-allowed}
.btn-block{width:100%}
.btn-sm{padding:6px 12px;font-size:.82rem;border-radius:8px;font-weight:600}
.btn-danger{background:#dc2626}.btn-danger:hover{background:#b91c1c}
.btn-ghost{background:var(--bg);color:var(--ink);border:1px solid var(--line)}
.btn-ghost:hover{background:var(--line);color:var(--ink)}
.btn-accent{background:var(--accent)}.btn-accent:hover{background:#ea580c}
.options{margin:18px 0;display:grid;gap:14px}
.opt{display:grid;gap:6px}
.opt label{font-weight:600;font-size:.9rem}
.opt input[type=text],.opt input[type=number],.opt input[type=password],.opt select,.opt textarea{
  width:100%;padding:10px 12px;border:1px solid var(--line);border-radius:10px;font-size:.95rem;background:#fff;
}
.opt input:focus,.opt select:focus,.opt textarea:focus{outline:2px solid var(--brand);border-color:var(--brand)}
.row{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.status{display:none;margin-top:16px;padding:14px;border-radius:10px;font-size:.95rem}
.status.show{display:block}
.status.ok{background:#ecfdf5;border:1px solid #a7f3d0;color:#065f46}
.status.err{background:#fef2f2;border:1px solid #fecaca;color:#991b1b}
.status.wait{background:var(--brand-soft);border:1px solid #bfdbfe;color:#1e40af}
.result-area{margin-top:14px;display:grid;gap:10px}
.result-item{display:flex;align-items:center;gap:12px;background:#ecfdf5;border:1px solid #a7f3d0;border-radius:10px;padding:12px 14px}
.result-item .ri-name{flex:1;font-weight:600;font-size:.9rem;word-break:break-all}
.result-item a{background:var(--brand);color:#fff;padding:8px 14px;border-radius:8px;font-size:.85rem;font-weight:700}
.result-item a:hover{background:var(--brand-dark);text-decoration:none}
.tool-meta{margin-top:22px;border-top:1px solid var(--line);padding-top:16px;font-size:.9rem;color:var(--muted)}
.hint{font-size:.82rem;color:var(--muted);margin-top:6px}
.page-thumbs{display:grid;grid-template-columns:repeat(auto-fill,minmax(110px,1fr));gap:12px;margin-top:14px}
.page-thumb{border:1px solid var(--line);border-radius:10px;overflow:hidden;background:#fff}
.page-thumb canvas{width:100%;height:auto;display:block}
.page-thumb .pt-label{text-align:center;font-size:.72rem;color:var(--muted);padding:4px}
.sig-canvas{border:2px solid var(--line);border-radius:10px;background:#fff;width:100%;touch-action:none;cursor:crosshair}

/* ---------- Sidebar / ads ---------- */
.sidebar{position:sticky;top:86px;display:grid;gap:18px}
.ad-slot{background:var(--card);border:1px dashed var(--line);border-radius:12px;min-height:250px;display:flex;flex-direction:column;align-items:center;justify-content:center;color:var(--muted);font-size:.8rem;text-align:center;padding:16px}
.ad-slot.ad-banner{min-height:90px}
.ad-slot.ad-side{min-height:600px}
.ad-note{font-size:.7rem;opacity:.7;margin-top:4px}
.ad-inline{background:var(--card);border:1px dashed var(--line);border-radius:12px;min-height:90px;display:flex;align-items:center;justify-content:center;color:var(--muted);font-size:.8rem;margin:26px 0;padding:14px}

/* ---------- Content ---------- */
.content-article{max-width:760px;margin:0 auto;padding-top:10px}
.content-article h2{font-size:1.3rem;margin:28px 0 10px;letter-spacing:-.01em}
.content-article h3{font-size:1.05rem;margin:20px 0 8px}
.content-article p,.content-article li{color:#334155;font-size:.98rem;margin-bottom:10px}
.content-article ul,.content-article ol{padding-left:22px;margin-bottom:14px}
.faq-item{margin-bottom:12px}
.faq-item details{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:14px 16px}
.faq-item summary{font-weight:700;cursor:pointer}

/* ---------- Footer ---------- */
.site-footer{background:#0f172a;color:#94a3b8;padding:36px 0 22px;margin-top:auto}
.site-footer .cols{display:grid;grid-template-columns:repeat(auto-fit,minmax(170px,1fr));gap:24px;margin-bottom:20px}
.site-footer h4{color:#fff;font-size:.95rem;margin-bottom:10px}
.site-footer a{color:#94a3b8;display:block;padding:3px 0;font-size:.88rem}
.site-footer a:hover{color:#fff}
.footer-bottom{border-top:1px solid #1e293b;padding-top:16px;font-size:.8rem;display:flex;justify-content:space-between;gap:10px;flex-wrap:wrap}

/* ---------- Misc ---------- */
.section-title{font-size:1.35rem;margin-top:40px;letter-spacing:-.01em}
.text-muted{color:var(--muted)}
.loader{display:inline-block;width:16px;height:16px;border:2px solid rgba(255,255,255,.4);border-top-color:#fff;border-radius:50%;animation:spin .7s linear infinite;vertical-align:-3px}
@keyframes spin{to{transform:rotate(360deg)}}
.error-page{text-align:center;padding:60px 18px}
.error-page h1{font-size:4rem;color:var(--brand)}
.skip-link{position:absolute;left:-999px;top:0;background:var(--brand);color:#fff;padding:8px 14px;z-index:100}
.skip-link:focus{left:10px}

/* ---------- Responsive ---------- */
@media(max-width:900px){
  .tool-layout{grid-template-columns:1fr}
  .sidebar{position:static;grid-template-columns:1fr 1fr}
  .ad-side{min-height:120px}
}
@media(max-width:640px){
  .nav-links{display:none;width:100%;flex-direction:column;background:var(--card);border:1px solid var(--line);border-radius:10px;padding:10px}
  .nav-links.open{display:flex}
  .menu-toggle{display:block}
  .row{grid-template-columns:1fr}
  .sidebar{grid-template-columns:1fr}
  .container{padding:0 14px}
  main{padding:20px 0 36px}
}