/* ============================================================
   AmiPDF main.css — single source of truth for all pages
   Code-ification of docs/ui-spec-web.md (v1.3). Keep in sync.
   Sections: 1 tokens · 2 base · 3 layout · 4 header/dropdowns
   5 tool icon chips · 6 tool panel · 7 content blocks
   8 footer · 9 toast · 10 responsive
   RTL-ready: logical properties only (inline-start/end).
   ============================================================ */

/* ============ 1. Design tokens (ui-spec §2) ============ */
:root{
  --c-primary:#3D5AF1; --c-primary-strong:#2F49C9; --c-primary-tint:#EBEFFE;
  --c-success:#178A50; --c-success-tint:#E6F6EE;
  --c-danger:#D93636; --c-danger-tint:#FCEBEB;
  --c-warning:#B45309; --c-warning-tint:#FEF3E2;
  --c-ink:#111827; --c-ink-2:#4B5563; --c-ink-3:#9CA3AF;
  --c-border:#E5E7EB; --c-border-2:#D1D5DB;
  --c-bg:#FFFFFF; --c-bg-alt:#F8FAFC;
  --c-footer-bg:#0F172A; --c-footer-ink:rgba(255,255,255,.75);
  --shadow-sm:0 1px 2px rgba(15,23,42,.06);
  --shadow-md:0 4px 12px rgba(15,23,42,.08);
  --shadow-lg:0 12px 32px rgba(15,23,42,.12);
  --r-sm:6px; --r-md:8px; --r-lg:12px;
  --font:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,"PingFang SC","Microsoft YaHei",sans-serif;
}

/* ============ 2. Base ============ */
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:var(--font);color:var(--c-ink);background:var(--c-bg);font-size:16px;line-height:26px}
a{color:var(--c-primary-strong);text-decoration:none}
a:hover{text-decoration:underline}
svg{display:block}
button{font-family:inherit}
:focus-visible{outline:2px solid var(--c-primary);outline-offset:2px;border-radius:4px}
.icon{width:24px;height:24px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.icon-14{width:14px;height:14px}
.icon-16{width:16px;height:16px}
.icon-18{width:18px;height:18px}
.icon-20{width:20px;height:20px}
.icon-22{width:22px;height:22px}
.icon-28{width:28px;height:28px}
.icon-64{width:64px;height:64px}
.spin{animation:spin 1s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important;animation:none!important}}

/* ============ 3. Layout (§3 full-width, tool panel 800px) ============ */
.container{width:100%;padding-inline:20px}
@media(min-width:1024px){.container{padding-inline:48px}}
.tool-flow{max-width:800px;margin-inline:auto}

/* ============ 4. Header & dropdowns (§4.1) ============ */
.site-header{position:sticky;top:0;z-index:100;background:#fff;border-bottom:1px solid var(--c-border)}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:64px;gap:16px}
.logo{display:flex;align-items:center;gap:10px;font-weight:700;font-size:20px;color:var(--c-ink)}
.logo:hover{text-decoration:none}
.logo svg{flex:none}
.header-nav{display:flex;align-items:center;gap:8px}
.nav-btn{display:flex;align-items:center;gap:8px;height:40px;padding-inline:14px;border:1px solid transparent;border-radius:var(--r-md);background:none;font-size:15px;font-weight:500;color:var(--c-ink-2);cursor:pointer}
.nav-btn:hover{background:var(--c-bg-alt);color:var(--c-ink)}
.dropdown{position:relative}
.dropdown-panel{position:absolute;top:calc(100% + 8px);inset-inline-end:0;background:#fff;border:1px solid var(--c-border);border-radius:var(--r-lg);box-shadow:var(--shadow-lg);padding:24px;display:none;grid-template-columns:repeat(3,220px);gap:24px;z-index:200}
.dropdown.open .dropdown-panel{display:grid}
.dd-group h4{font-size:12px;font-weight:600;color:var(--c-ink-3);text-transform:uppercase;letter-spacing:.04em;margin-bottom:12px}
.dd-group a{display:flex;align-items:center;gap:10px;font-size:14px;line-height:32px;color:var(--c-ink-2)}
.dd-group a:hover{color:var(--c-primary-strong)}
/* per-tool icon chips inside All Tools dropdown */
.dd-ico{width:20px;height:20px;border-radius:5px;color:#fff;display:flex;align-items:center;justify-content:center;flex:none}
/* language items: native names, no wrap, check on current */
.lang-item{white-space:nowrap}
.lang-item .lg-check{width:14px;height:14px;color:var(--c-primary);visibility:hidden;flex:none;fill:none;stroke:currentColor;stroke-width:2.5;stroke-linecap:round;stroke-linejoin:round}
.lang-item[aria-current="true"]{color:var(--c-ink);font-weight:600}
.lang-item[aria-current="true"] .lg-check{visibility:visible}
/* language chips — flag for single-country locales, script chip for zh-Hant & ar */
.lg-flag{width:20px;height:15px;border-radius:3px;overflow:hidden;flex:none;box-shadow:inset 0 0 0 1px rgba(15,23,42,.10);display:block}
.lg-flag svg{display:block;width:100%;height:100%}
.lg-badge{width:20px;height:15px;border-radius:3px;font-size:10px;font-weight:700;display:flex;align-items:center;justify-content:center;flex:none;line-height:1}
.lg-zh-hant{background:#FEF3E2;color:#B45309}
.lg-ar{background:#E6F3F4;color:#0E7490}
#lang-dd .dropdown-panel{grid-template-columns:1fr 1fr;min-width:480px}
@media(max-width:1023px){
  #lang-dd .dropdown-panel{min-width:0}
  .header-nav .nav-label{display:none}
}

/* ============ 5. Tool icon chips (§6, 18 gradients) ============ */
.t-ico{width:48px;height:48px;border-radius:12px;color:#fff;display:flex;align-items:center;justify-content:center;box-shadow:0 2px 6px rgba(15,23,42,.12)}
.ti-merge{background:linear-gradient(135deg,#3D5AF1,#7C9EFF)}
.ti-split{background:linear-gradient(135deg,#0E9F8F,#4ED8C4)}
.ti-organize{background:linear-gradient(135deg,#6366F1,#9AA5FB)}
.ti-rotate{background:linear-gradient(135deg,#8B5CF6,#B892FB)}
.ti-delete{background:linear-gradient(135deg,#EF4444,#F98A8A)}
.ti-extract{background:linear-gradient(135deg,#F59E0B,#FBC153)}
.ti-numbers{background:linear-gradient(135deg,#0891B2,#4FC8E0)}
.ti-crop{background:linear-gradient(135deg,#D97706,#F0A64B)}
.ti-img2pdf{background:linear-gradient(135deg,#F97316,#FB9E5C)}
.ti-jpg2pdf{background:linear-gradient(135deg,#F43F5E,#FB8AA2)}
.ti-png2pdf{background:linear-gradient(135deg,#22C55E,#6FD98F)}
.ti-pdf2jpg{background:linear-gradient(135deg,#E11D8F,#F268B8)}
.ti-pdf2png{background:linear-gradient(135deg,#10B981,#5FD9AC)}
.ti-watermark{background:linear-gradient(135deg,#14B8A6,#5FD9CB)}
.ti-protect{background:linear-gradient(135deg,#16A34A,#5FBF84)}
.ti-unlock{background:linear-gradient(135deg,#EAB308,#F5D04B)}
.ti-analyzer{background:linear-gradient(135deg,#7C3AED,#A980F2)}
.ti-metadata{background:linear-gradient(135deg,#64748B,#94A3B8)}

/* ============ 6. Tool panel (§4.4-4.7) ============ */
.crumb{font-size:14px;color:var(--c-ink-2);padding-block:24px 4px}
.crumb a{color:var(--c-ink-2)}
.crumb span[aria-current]{color:var(--c-ink-3)}
.tool-head h1{font-size:32px;line-height:40px;font-weight:700;letter-spacing:-.01em}
.trust-sub{display:flex;flex-wrap:wrap;align-items:center;gap:8px;font-size:14px;color:var(--c-ink-2);margin:8px 0 24px}
.trust-sub .dot{color:var(--c-border-2)}
.trust-sub strong{color:var(--c-success);font-weight:600}
.tool-panel{background:#fff;border:1px solid var(--c-border);border-radius:16px;box-shadow:var(--shadow-sm);padding:24px}
.dropzone{border:2px dashed var(--c-border-2);border-radius:var(--r-lg);min-height:240px;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:8px;text-align:center;padding:32px 16px;cursor:pointer;transition:border-color .15s,background .15s}
.dropzone:hover,.dropzone.dragover{border-color:var(--c-primary);background:var(--c-primary-tint)}
.dropzone .dz-icon{width:64px;height:64px;color:var(--c-primary);margin-bottom:8px}
.dropzone .dz-main{font-size:17px;font-weight:600}
.dropzone .dz-sub{font-size:14px;color:var(--c-ink-2)}
.dropzone .dz-cap{font-size:12px;color:var(--c-ink-3)}
.file-list{margin-top:16px;display:flex;flex-direction:column;gap:8px}
.file-row{display:flex;align-items:center;gap:12px;padding:12px 14px;border:1px solid var(--c-border);border-radius:var(--r-md);background:var(--c-bg-alt)}
.file-row .f-ico{color:var(--c-primary);flex:none}
.file-row .f-name{font-size:14px;font-weight:600;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.file-row .f-meta{font-size:12px;color:var(--c-ink-3);flex:none}
.file-row .f-acts{margin-inline-start:auto;display:flex;gap:4px;flex:none}
.icon-btn{width:32px;height:32px;display:flex;align-items:center;justify-content:center;border:none;background:none;border-radius:var(--r-sm);color:var(--c-ink-2);cursor:pointer}
.icon-btn:hover{background:var(--c-primary-tint);color:var(--c-primary-strong)}
.icon-btn:disabled{opacity:.35;cursor:default}
.icon-btn:disabled:hover{background:none;color:var(--c-ink-2)}
.opt-panel{margin-top:16px;border-top:1px solid var(--c-border);padding-top:16px}
.opt-label{font-size:14px;font-weight:600;margin-bottom:8px;color:var(--c-ink)}
.hint{font-size:13px;color:var(--c-ink-3);margin-top:8px}
.action-bar{margin-top:20px;display:flex;flex-direction:column;gap:12px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;height:48px;padding-inline:28px;border-radius:var(--r-md);font-size:16px;font-weight:600;cursor:pointer;border:1px solid transparent;transition:background .15s}
.btn-primary{background:var(--c-primary);color:#fff;width:100%}
.btn-primary:hover:not(:disabled){background:var(--c-primary-strong)}
.btn-primary:disabled{opacity:.4;cursor:not-allowed}
.btn-success{background:var(--c-success);color:#fff;width:100%}
.btn-success:hover{background:#136B3E}
.btn-link{background:none;border:none;color:var(--c-primary-strong);font-size:14px;height:auto;padding:0;cursor:pointer}
.btn-link:hover{text-decoration:underline}
.progress-wrap{margin-top:20px}
.progress-track{height:6px;border-radius:999px;background:var(--c-border);overflow:hidden}
.progress-bar{height:100%;width:0;background:var(--c-primary);border-radius:999px;transition:width .2s}
.progress-text{font-size:14px;color:var(--c-ink-2);margin-top:8px;display:flex;justify-content:space-between}
.result-card{margin-top:20px;background:var(--c-success-tint);border:1px solid #CBE9D8;border-radius:var(--r-lg);padding:20px}
.result-top{display:flex;align-items:center;gap:12px}
.result-top .r-ico{color:var(--c-success)}
.result-name{font-size:15px;font-weight:600}
.result-meta{font-size:13px;color:var(--c-ink-2)}
.result-acts{margin-top:16px;display:flex;flex-direction:column;gap:8px}

/* ============ 7. Content blocks (§4.8, §5) ============ */
.stats-band{background:var(--c-bg-alt);border-top:1px solid var(--c-border);border-bottom:1px solid var(--c-border);margin:56px -20px 0;padding:32px 20px}
@media(min-width:1024px){.stats-band{margin:56px -48px 0;padding:32px 48px}}
.stats-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px;text-align:center}
.stat .s-num{font-size:28px;line-height:36px;font-weight:700;color:var(--c-primary-strong)}
.stat .s-label{font-size:13px;color:var(--c-ink-2);margin-top:2px}
.section{margin-top:56px}
.section-intro p{color:var(--c-ink-2);font-size:15px;line-height:24px;margin-top:8px}
.section h2{font-size:24px;line-height:32px;font-weight:600;letter-spacing:-.01em}
.howto-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-top:24px}
.step-card{background:var(--c-bg-alt);border-radius:var(--r-lg);padding:24px}
.step-num{width:32px;height:32px;border-radius:999px;background:var(--c-primary-tint);color:var(--c-primary-strong);display:flex;align-items:center;justify-content:center;font-weight:700;font-size:15px;margin-bottom:12px}
.step-card h3{font-size:16px;font-weight:600;margin-bottom:4px}
.step-card p{font-size:14px;line-height:22px;color:var(--c-ink-2)}
.feat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-top:24px}
.feat{padding:20px;border:1px solid var(--c-border);border-radius:var(--r-lg)}
.feat .f-ico2{width:40px;height:40px;border-radius:var(--r-md);background:var(--c-primary-tint);color:var(--c-primary-strong);display:flex;align-items:center;justify-content:center;margin-bottom:14px}
.feat h3{font-size:15px;font-weight:600}
.feat p{font-size:14px;line-height:22px;color:var(--c-ink-2);margin-top:4px}
.usecase-wrap{display:grid;grid-template-columns:5fr 7fr;gap:40px;margin-top:8px;align-items:start}
.usecase-wrap p{color:var(--c-ink-2);font-size:15px;line-height:24px;margin-top:8px}
.chip-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:12px}
.chip{display:flex;align-items:center;gap:12px;padding:14px 16px;border:1px solid var(--c-border);border-radius:var(--r-md);background:#fff;font-size:14px;font-weight:500;color:var(--c-ink)}
.chip svg{color:var(--c-primary);flex:none}
.platform-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:16px;margin-top:24px}
.platform{padding:20px 12px;text-align:center;border:1px solid var(--c-border);border-radius:var(--r-lg)}
.platform svg{margin-inline:auto 10px;color:var(--c-primary)}
.platform h3{font-size:14px;font-weight:600}
.platform p{font-size:12px;line-height:18px;color:var(--c-ink-3);margin-top:2px}
.faq details{border-bottom:1px solid var(--c-border)}
.faq summary{display:flex;align-items:center;justify-content:space-between;gap:12px;padding-block:16px;font-size:16px;font-weight:600;cursor:pointer;list-style:none}
.faq summary::-webkit-details-marker{display:none}
.faq summary svg{flex:none;transition:transform .15s;color:var(--c-ink-3)}
.faq details[open] summary svg{transform:rotate(180deg)}
.faq .faq-a{padding-block-end:16px;font-size:15px;line-height:24px;color:var(--c-ink-2)}
.tool-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-top:24px}
.tool-card{display:flex;flex-direction:column;gap:8px;padding:20px;background:#fff;border:1px solid var(--c-border);border-radius:var(--r-lg);color:var(--c-ink);transition:box-shadow .15s,transform .15s}
.tool-card:hover{box-shadow:var(--shadow-md);transform:translateY(-2px);text-decoration:none}
.tool-card .t-name{font-size:16px;font-weight:600}
.tool-card .t-desc{font-size:14px;line-height:22px;color:var(--c-ink-2);display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.cta-banner{margin-top:64px;background:var(--c-primary-tint);border-radius:20px;padding:48px 32px;text-align:center}
.cta-banner h2{font-size:26px;line-height:34px;font-weight:700}
.cta-banner p{color:var(--c-ink-2);font-size:15px;margin:8px auto 24px}
.cta-banner .btn{background:var(--c-primary);color:#fff;height:48px;padding-inline:32px}
.cta-banner .btn:hover{background:var(--c-primary-strong)}

/* ============ 8. Footer (§4.2) ============ */
.site-footer{background:var(--c-footer-bg);color:var(--c-footer-ink);margin-top:72px;padding-block:48px 24px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:32px}
.footer-brand .logo{color:#fff}
.footer-brand p{font-size:14px;line-height:22px;margin-top:12px}
.f-col h4{font-size:13px;font-weight:600;color:#fff;text-transform:uppercase;letter-spacing:.04em;margin-bottom:12px}
.f-col a{display:block;font-size:14px;line-height:26px;color:var(--c-footer-ink)}
.f-col a:hover{color:#fff;text-decoration:none}
.footer-bottom{margin-top:40px;padding-top:20px;border-top:1px solid rgba(255,255,255,.12);font-size:13px;color:var(--c-footer-ink)}

/* ============ 9. Toast (§4.9) ============ */
.toast{position:fixed;inset-inline-end:20px;bottom:20px;z-index:300;background:var(--c-ink);color:#fff;font-size:14px;padding:12px 18px;border-radius:var(--r-md);box-shadow:var(--shadow-lg);opacity:0;pointer-events:none;transition:opacity .2s}
.toast.show{opacity:1}
@media(max-width:1023px){.toast{inset-inline:20px auto 20px;bottom:auto;top:12px;margin-inline:auto}}

/* ============ 10. Responsive (§7) ============ */
@media(max-width:1023px){
  .tool-grid{grid-template-columns:repeat(2,1fr)}
  .howto-grid{grid-template-columns:1fr}
  .feat-grid{grid-template-columns:repeat(2,1fr)}
  .usecase-wrap{grid-template-columns:1fr;gap:24px}
  .platform-grid{grid-template-columns:repeat(3,1fr)}
  .stats-grid{grid-template-columns:repeat(2,1fr)}
  .dropdown-panel{grid-template-columns:1fr;inset-inline:0;max-height:60vh;overflow:auto}
  .footer-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:639px){
  .tool-grid{grid-template-columns:1fr}
  .feat-grid{grid-template-columns:1fr}
  .platform-grid{grid-template-columns:repeat(2,1fr)}
  .chip-grid{grid-template-columns:1fr}
  .tool-head h1{font-size:26px;line-height:34px}
}