:root{--bg:#f7f7fc;--surface:#fff;--ink:#14132b;--ink2:#47476a;--muted:#7a7a98;--line:#e7e6f2;--line2:#d9d7ea;
 --brand:#6d5dfc;--brand-d:#5443e8;--brand-soft:#efedff;--pink:#ff5c8a;--pink-soft:#ffeef3;--mint:#0fb97f;--sun:#ffb020;
 --r:18px;--sh:0 1px 2px rgba(20,19,43,.04),0 8px 24px -8px rgba(20,19,43,.08);--sh-lg:0 2px 4px rgba(20,19,43,.03),0 24px 60px -20px rgba(80,60,200,.22)}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{font-family:'Plus Jakarta Sans',system-ui,-apple-system,'Segoe UI',Roboto,sans-serif;background:var(--bg);color:var(--ink);line-height:1.65;font-size:16px;-webkit-font-smoothing:antialiased}
a{color:var(--brand-d);text-decoration:none}a:hover{text-decoration:underline}
button,input,textarea{font:inherit;color:inherit}button{cursor:pointer;background:none;border:0}
.i{width:18px;height:18px;flex:none}
.wrap{max-width:1120px;margin:0 auto;padding:0 20px}
.skip{position:absolute;left:-999px;top:8px;background:var(--ink);color:#fff;padding:8px 14px;border-radius:8px;z-index:100}.skip:focus{left:8px}
:focus-visible{outline:3px solid rgba(109,93,252,.45);outline-offset:2px;border-radius:8px}

/* header */
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.82);backdrop-filter:saturate(1.6) blur(14px);-webkit-backdrop-filter:saturate(1.6) blur(14px);border-bottom:1px solid var(--line)}
.site-header .wrap{display:flex;align-items:center;justify-content:space-between;height:66px}
.logo{display:inline-flex;align-items:center;gap:10px;font-weight:800;font-size:1.22rem;color:var(--ink);letter-spacing:-.02em}.logo:hover{text-decoration:none}
.logo b{background:linear-gradient(120deg,var(--brand),var(--pink));-webkit-background-clip:text;background-clip:text;color:transparent}
.mark{width:34px;height:34px;filter:drop-shadow(0 4px 10px rgba(109,93,252,.35))}
nav#siteNav{display:flex;gap:4px}
nav#siteNav a{padding:8px 14px;border-radius:999px;color:var(--ink2);font-weight:600;font-size:.94rem}
nav#siteNav a:hover{background:var(--brand-soft);color:var(--brand-d);text-decoration:none}
nav#siteNav a.on{background:var(--ink);color:#fff}
.menu-btn{display:none;width:42px;height:42px;border-radius:12px;align-items:center;justify-content:center;border:1px solid var(--line)}
@media(max-width:760px){
 .menu-btn{display:inline-flex}
 nav#siteNav{display:none;position:absolute;top:66px;left:0;right:0;flex-direction:column;background:#fff;padding:10px 16px 16px;border-bottom:1px solid var(--line);box-shadow:var(--sh)}
 .nav-open nav#siteNav{display:flex}
 nav#siteNav a{padding:12px 14px}
}
.ad{max-width:1120px;margin:14px auto;text-align:center;overflow:hidden;padding:0 16px}

/* hero + tool */
.hero{position:relative;padding:34px 0 26px;overflow:hidden}
.hero:before{content:"";position:absolute;inset:-200px -10% auto;height:640px;z-index:-1;
 background:radial-gradient(420px 300px at 18% 30%,rgba(109,93,252,.20),transparent 70%),radial-gradient(380px 280px at 82% 18%,rgba(255,92,138,.18),transparent 70%),radial-gradient(420px 260px at 60% 75%,rgba(32,201,240,.14),transparent 70%)}
.tool{background:var(--surface);border:1px solid var(--line);border-radius:28px;padding:26px;box-shadow:var(--sh-lg)}
.modes{display:grid;grid-template-columns:1fr 1fr;gap:6px;background:#f1f0fa;border:1px solid var(--line);padding:6px;border-radius:18px;max-width:520px;margin:0 auto 22px}
.mode{display:flex;align-items:center;justify-content:center;gap:9px;padding:13px 10px;border-radius:13px;font-weight:700;font-size:1rem;color:var(--ink2);transition:background .2s,color .2s,box-shadow .2s}
.mode:hover{color:var(--ink)}
.mode[aria-selected=true]{background:linear-gradient(135deg,var(--brand),#8b5cf6 55%,var(--pink));color:#fff;box-shadow:0 8px 20px -8px rgba(109,93,252,.7)}
.mode .i{width:19px;height:19px}
.tool-head{text-align:center;margin-bottom:22px}
.tool-head h1{font-size:clamp(1.9rem,4.4vw,2.9rem);line-height:1.12;letter-spacing:-.035em;font-weight:800}
.tool-head p{color:var(--ink2);max-width:640px;margin:10px auto 0;font-size:1.02rem}
.tool-grid{display:grid;grid-template-columns:1.25fr 1fr;gap:16px;margin-bottom:16px}
@media(max-width:860px){.tool-grid{grid-template-columns:1fr}.tool{padding:16px;border-radius:22px}}
.card{background:#fbfbfe;border:1px solid var(--line);border-radius:var(--r);padding:16px}
.card-h{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-bottom:10px}
.card-h label{font-weight:700;font-size:.95rem}
.card-f{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:10px;margin-top:12px}
.meta{font-size:.84rem;color:var(--muted)}.meta b{color:var(--ink);font-weight:700}
textarea{width:100%;min-height:150px;resize:vertical;background:#fff;border:1.5px solid var(--line2);border-radius:14px;padding:14px 16px;font-size:1.02rem;line-height:1.6;outline:0;transition:border-color .2s,box-shadow .2s}
textarea:focus,input[type=text]:focus,input[type=number]:focus{border-color:var(--brand);box-shadow:0 0 0 4px rgba(109,93,252,.14)}
#outputText{min-height:130px;max-height:300px;background:#fff}
.ghost{display:inline-flex;align-items:center;gap:6px;font-size:.85rem;font-weight:600;color:var(--ink2);padding:6px 11px;border-radius:10px;border:1px solid var(--line);background:#fff}
.ghost:hover{border-color:var(--brand);color:var(--brand-d)}.ghost .i{width:15px;height:15px}
.inline-btns{display:flex;gap:8px;flex-wrap:wrap}
.chips{display:flex;flex-wrap:wrap;gap:7px;margin-top:12px}
.chip{padding:6px 12px;border-radius:999px;background:#fff;border:1px solid var(--line);font-size:.84rem;font-weight:600;color:var(--ink2);transition:.15s}
.chip:hover{border-color:var(--brand);color:var(--brand-d);background:var(--brand-soft)}
.tool[data-mode=repeat] [data-for=invert],.tool[data-mode=invert] [data-for=repeat]{display:none}
.lbl{font-weight:700;font-size:.9rem;margin:16px 0 8px}.lbl:first-child{margin-top:2px}
.opt-note{font-weight:500;color:var(--muted);font-size:.8rem;margin-left:4px}
.stepper{display:flex;align-items:center;background:#fff;border:1.5px solid var(--line2);border-radius:14px;padding:5px;width:100%}
.stepper button{width:44px;height:44px;border-radius:10px;display:grid;place-items:center;background:#f3f2fb;color:var(--ink)}
.stepper button:hover{background:var(--brand-soft);color:var(--brand-d)}
#repeatCount{flex:1;min-width:0;border:0;background:none;text-align:center;font-size:1.5rem;font-weight:800;letter-spacing:-.02em;outline:0;-moz-appearance:textfield}
#repeatCount::-webkit-inner-spin-button,#repeatCount::-webkit-outer-spin-button{-webkit-appearance:none;margin:0}
.presets{display:grid;grid-template-columns:repeat(4,1fr);gap:8px;margin-top:10px}
.pre{display:flex;flex-direction:column;align-items:center;padding:9px 4px;border-radius:12px;background:#fff;border:1.5px solid var(--line);font-weight:800;font-size:1.02rem;line-height:1.2;transition:.15s}
.pre small{font-weight:500;font-size:.7rem;color:var(--muted)}
.pre:hover{border-color:var(--brand)}
.pre.on{border-color:var(--brand);background:var(--brand-soft);color:var(--brand-d)}.pre.on small{color:var(--brand-d)}
.seg{display:flex;flex-wrap:wrap;gap:6px}
.seg button{padding:8px 13px;border-radius:10px;background:#fff;border:1.5px solid var(--line);font-size:.86rem;font-weight:600;color:var(--ink2)}
.seg button:hover{border-color:var(--brand)}
.seg button.on{background:var(--ink);border-color:var(--ink);color:#fff}
#customSep{margin-top:8px;width:100%;padding:10px 14px;border-radius:12px;border:1.5px solid var(--line2);outline:0;background:#fff}
.inv-list{display:grid;gap:8px}
.inv{display:flex;align-items:center;justify-content:space-between;gap:10px;text-align:left;padding:13px 15px;border-radius:14px;background:#fff;border:1.5px solid var(--line);transition:.15s}
.inv b{font-size:.95rem}.inv span{color:var(--muted);font-size:.88rem;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.inv:hover{border-color:var(--brand)}
.inv.on{border-color:var(--brand);background:var(--brand-soft);box-shadow:inset 4px 0 0 var(--brand)}.inv.on span{color:var(--brand-d)}
.hint{margin-top:12px;font-size:.86rem;color:var(--ink2);background:#fff8e8;border:1px solid #ffe3a6;padding:10px 12px;border-radius:12px}
.out .card-h label{font-size:1rem}
.actions{display:flex;flex-wrap:wrap;gap:8px;margin-top:12px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:11px 16px;border-radius:12px;font-weight:700;font-size:.92rem;background:#fff;border:1.5px solid var(--line2);color:var(--ink);transition:.15s}
.btn:hover{border-color:var(--ink);text-decoration:none}
.btn.primary{background:linear-gradient(135deg,var(--brand),#8b5cf6);border-color:transparent;color:#fff;padding:11px 24px;box-shadow:0 10px 22px -10px rgba(109,93,252,.8)}
.btn.primary:hover{filter:brightness(1.07);transform:translateY(-1px)}
.btn.primary.done{background:var(--mint);box-shadow:none}
.btn{white-space:nowrap}
@media(max-width:560px){.actions{display:grid;grid-template-columns:1fr 1fr}.actions .btn{padding:11px 8px;font-size:.86rem}.actions .btn.primary{grid-column:1/-1}
 .mode{font-size:.92rem;padding:12px 6px;gap:7px}.mode .i{width:16px;height:16px}.modes{margin-bottom:16px}}
@media(max-width:360px){.mode .i{display:none}}
.trust{list-style:none;display:flex;flex-wrap:wrap;justify-content:center;gap:10px 26px;margin-top:20px;color:var(--ink2);font-size:.9rem;font-weight:600}
.trust li{display:flex;align-items:center;gap:8px}.trust .i{color:var(--brand)}
#toast{position:fixed;bottom:24px;left:50%;transform:translate(-50%,20px);background:var(--ink);color:#fff;padding:12px 20px;border-radius:12px;font-size:.92rem;font-weight:600;opacity:0;pointer-events:none;transition:.25s;z-index:99;max-width:calc(100% - 32px);text-align:center}
#toast.show{opacity:1;transform:translate(-50%,0)}

/* inner page hero */
.page-hero{position:relative;padding:54px 0 34px;overflow:hidden;border-bottom:1px solid var(--line);background:linear-gradient(180deg,#fff,var(--bg))}
.page-hero:before{content:"";position:absolute;inset:-160px 0 auto;height:420px;z-index:0;background:radial-gradient(380px 220px at 12% 40%,rgba(109,93,252,.16),transparent 70%),radial-gradient(360px 220px at 88% 20%,rgba(255,92,138,.14),transparent 70%)}
.page-hero .wrap{position:relative;max-width:860px}
.page-hero h1{font-size:clamp(2rem,4.6vw,3rem);line-height:1.1;letter-spacing:-.035em;font-weight:800;margin:12px 0}
.page-hero p{color:var(--ink2);font-size:1.08rem;max-width:680px}
.page-hero .updated{font-size:.86rem;color:var(--muted);margin-top:14px}
.page-hero.center{text-align:center}.page-hero.center p{margin:0 auto}
.cta-row{display:flex;gap:10px;justify-content:center;flex-wrap:wrap;margin-top:22px!important}
.crumbs{display:flex;align-items:center;gap:6px;font-size:.86rem;color:var(--muted)}.crumbs .i{width:14px;height:14px}

/* article */
.article-wrap{display:grid;grid-template-columns:250px minmax(0,1fr);gap:48px;padding-top:44px;padding-bottom:30px;max-width:1120px}
.article-wrap.no-toc{grid-template-columns:minmax(0,760px);justify-content:center}
.toc{position:sticky;top:90px;align-self:start;max-height:calc(100vh - 110px);overflow:auto}
.toc summary{display:flex;align-items:center;gap:8px;font-weight:700;font-size:.9rem;cursor:pointer;list-style:none;margin-bottom:10px}.toc summary::-webkit-details-marker{display:none}
.toc ol{list-style:none;border-left:2px solid var(--line);font-size:.88rem}
.toc a{display:block;padding:5px 0 5px 14px;margin-left:-2px;border-left:2px solid transparent;color:var(--ink2);line-height:1.4}
.toc a:hover{color:var(--brand-d);border-left-color:var(--brand);text-decoration:none}
@media(max-width:960px){.article-wrap{grid-template-columns:minmax(0,1fr);gap:24px}.toc{position:static;max-height:none;background:#fff;border:1px solid var(--line);border-radius:16px;padding:14px 16px}.toc summary{margin:0}.toc details[open] summary{margin-bottom:10px}}
.prose{max-width:760px;font-size:1.04rem;color:#2a2a47}
.prose h2{font-size:clamp(1.45rem,2.6vw,1.8rem);line-height:1.25;letter-spacing:-.025em;color:var(--ink);margin:2.4em 0 .6em;scroll-margin-top:90px;font-weight:800}
.prose h2:first-child{margin-top:0}
.prose h3{font-size:1.17rem;color:var(--ink);margin:1.7em 0 .45em;letter-spacing:-.01em;font-weight:700}
.prose p,.prose ul,.prose ol,.prose table,.prose blockquote{margin-bottom:1.05em}
.prose ul,.prose ol{padding-left:1.35em}.prose li{margin-bottom:.45em}.prose li::marker{color:var(--brand)}
.prose strong{color:var(--ink)}
.prose code{background:var(--brand-soft);color:var(--brand-d);padding:2px 6px;border-radius:6px;font-size:.92em}
.prose blockquote{border-left:4px solid var(--brand);background:#fff;padding:14px 18px;border-radius:0 12px 12px 0;color:var(--ink2)}
.prose table{width:100%;border-collapse:separate;border-spacing:0;font-size:.95rem;background:#fff;border:1px solid var(--line);border-radius:14px;overflow:hidden;display:block;overflow-x:auto}
.prose th,.prose td{padding:11px 14px;text-align:left;border-bottom:1px solid var(--line);vertical-align:top}
.prose th{background:#f4f3fc;font-weight:700;color:var(--ink);white-space:nowrap}
.prose tr:last-child td{border-bottom:0}
.prose .lead{font-size:1.15rem;color:var(--ink2)}
.prose .note{background:#fff;border:1px solid var(--line);border-left:4px solid var(--sun);border-radius:12px;padding:14px 18px}
.prose .grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:12px;margin:1.2em 0 1.6em}
.prose .grid>div{background:#fff;border:1px solid var(--line);border-radius:16px;padding:16px 18px;box-shadow:var(--sh)}
.prose .grid h3{margin:0 0 .35em;font-size:1.02rem}.prose .grid p{margin:0;font-size:.95rem;color:var(--ink2)}
.prose .faq h3{margin-top:1.4em;padding-top:1.1em;border-top:1px solid var(--line)}
.prose .faq h3:first-of-type{border-top:0;padding-top:0}
.prose .cta{display:flex;flex-wrap:wrap;gap:10px;margin:1.4em 0}

/* footer */
.site-footer{margin-top:50px;background:#fff;border-top:1px solid var(--line);padding:46px 0 26px}
.site-footer .wrap{display:grid;grid-template-columns:1.6fr 1fr 1fr 1fr;gap:30px}
.f-brand p{color:var(--ink2);font-size:.92rem;margin-top:12px;max-width:340px}
.f-col h4{font-size:.8rem;text-transform:uppercase;letter-spacing:.08em;color:var(--muted);margin-bottom:12px}
.f-col a{display:block;color:var(--ink2);font-size:.94rem;padding:4px 0}
.copy{grid-column:1/-1;border-top:1px solid var(--line);padding-top:18px;font-size:.86rem;color:var(--muted)}
@media(max-width:760px){.site-footer .wrap{grid-template-columns:1fr 1fr}.f-brand{grid-column:1/-1}}