:root{--bg:#f7f8fc;--card:#fff;--ink:#0f172a;--muted:#5b6478;--line:#e3e7f0;--brand:#4f46e5;--brand-2:#7c3aed;--brand-soft:#eef0ff;--ok:#047857;--err:#b91c1c;--r:14px;--shadow:0 1px 2px rgba(15,23,42,.05),0 4px 16px rgba(15,23,42,.06)}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;font:16px/1.65 -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Inter,Arial,sans-serif;color:var(--ink);background:var(--bg)}
a{color:var(--brand);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;height:auto}
h1,h2,h3{line-height:1.25;letter-spacing:-.01em}
h1{font-size:clamp(1.7rem,4vw,2.4rem);margin:.4em 0 .3em}
h2{font-size:1.4rem;margin:1.6em 0 .6em}
.wrap{max-width:1180px;margin:0 auto;padding:0 16px}
.narrow{max-width:780px}
.center{text-align:center}
.muted{color:var(--muted)}
.small{font-size:.87rem}
.lead{font-size:1.1rem;color:var(--muted);margin-top:0}
.btn{display:inline-block;background:var(--brand);color:#fff;border:0;border-radius:10px;padding:.7em 1.2em;font-weight:600;font-size:1rem;cursor:pointer}
.btn:hover{background:#4338ca;text-decoration:none}
.btn.ghost{background:transparent;color:var(--brand);border:1px solid var(--line)}
/* header */
.top{background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}
.bar{display:flex;align-items:center;gap:18px;min-height:62px}
.logo{display:flex;align-items:center;gap:8px;font-weight:800;font-size:1.2rem;color:var(--ink)}
.logo:hover{text-decoration:none}
.logo-mark{display:grid;place-items:center;width:32px;height:32px;border-radius:9px;background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;font-size:1rem}
.nav{display:flex;gap:16px;flex:1;overflow:hidden;white-space:nowrap}
.nav a{color:var(--ink);font-weight:500;font-size:.95rem}
.search input{border:1px solid var(--line);border-radius:10px;padding:.5em .8em;width:210px;font-size:.95rem;background:var(--bg)}
.nav-toggle{display:none;margin-left:auto;background:none;border:1px solid var(--line);border-radius:8px;font-size:1.2rem;padding:.2em .6em;cursor:pointer}
@media(max-width:900px){.nav{display:none;position:absolute;left:0;right:0;top:62px;background:#fff;flex-direction:column;padding:12px 16px;border-bottom:1px solid var(--line)}.nav.open{display:flex}.nav-toggle{display:block}.search{display:none}}
/* hero */
.hero{background:radial-gradient(1200px 400px at 50% -10%,#e0e3ff,transparent),var(--bg);padding:48px 0 24px}
.hero-search{display:flex;gap:8px;max-width:620px;margin:22px auto}
.hero-search input{flex:1;border:1px solid var(--line);border-radius:12px;padding:.85em 1em;font-size:1.05rem;box-shadow:var(--shadow)}
.chips{display:flex;flex-wrap:wrap;gap:8px;justify-content:center}
.chip{background:#fff;border:1px solid var(--line);border-radius:999px;padding:.35em .9em;color:var(--ink);font-size:.92rem}
.chip small{color:var(--muted);margin-left:4px}
.sec-head{display:flex;justify-content:space-between;align-items:baseline;margin-top:36px}
.sec-head h2{margin:0 0 12px}
/* cards */
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:12px}
.card{display:flex;gap:12px;background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:14px;color:var(--ink);transition:.15s}
.card:hover{border-color:var(--brand);box-shadow:var(--shadow);text-decoration:none;transform:translateY(-1px)}
.card .ic{flex:none;display:grid;place-items:center;width:40px;height:40px;border-radius:10px;background:var(--brand-soft);color:var(--brand);font-weight:700}
.card-body{display:flex;flex-direction:column;min-width:0}
.card strong{font-size:.98rem}
.flag{font-size:.85rem;margin-left:6px}
.country-row{display:grid;grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:12px}
.country{display:flex;align-items:center;gap:10px;background:#fff;border:1px solid var(--line);border-radius:var(--r);padding:14px;color:var(--ink);font-weight:600}
.country span{font-size:1.6rem}
.cat-title{margin-top:32px}
.filter{width:100%;max-width:420px;border:1px solid var(--line);border-radius:10px;padding:.6em .9em;font-size:1rem;margin:8px 0}
/* breadcrumbs */
.crumbs{font-size:.86rem;color:var(--muted);margin-top:18px;display:flex;flex-wrap:wrap;gap:6px}
.crumbs a{color:var(--muted)}
/* tool page */
.tool-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:28px;padding-bottom:40px}
@media(max-width:960px){.tool-layout{grid-template-columns:1fr}}
.badge{display:inline-block;background:var(--brand-soft);color:var(--brand);border-radius:999px;padding:.2em .8em;font-size:.88rem;font-weight:600;margin:0 0 8px}
.tool-box{background:var(--card);border:1px solid var(--line);border-radius:18px;padding:22px;box-shadow:var(--shadow)}
.tz-form,.tz-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:14px}
.tz-field label,.tool-box label{display:block;font-weight:600;font-size:.92rem;margin-bottom:4px}
.tz-field .help{display:block;color:var(--muted);font-size:.8rem;margin-top:3px}
.tool-box input,.tool-box select,.tool-box textarea{width:100%;border:1px solid #cfd5e3;border-radius:10px;padding:.65em .75em;font-size:1rem;background:#fff;font-family:inherit;color:var(--ink)}
.tool-box input:focus,.tool-box select:focus,.tool-box textarea:focus{outline:2px solid #c7d2fe;border-color:var(--brand)}
.in-unit{position:relative}
.in-unit span{position:absolute;right:10px;top:50%;transform:translateY(-50%);color:var(--muted);font-size:.85rem;pointer-events:none}
.in-unit input{padding-right:52px}
.results{margin-top:18px;display:grid;grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:12px}
.res{background:var(--brand-soft);border-radius:12px;padding:14px}
.res .k{font-size:.85rem;color:var(--muted)}
.res .v{font-size:1.35rem;font-weight:800;color:var(--ink);word-break:break-word}
.res.main{background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;grid-column:1/-1}
.res.main .k{color:#e0e7ff}
.res.main .v{color:#fff;font-size:1.9rem}
.res-note{grid-column:1/-1;font-size:.9rem;color:var(--muted)}
.row-actions{display:flex;gap:8px;flex-wrap:wrap;margin-top:12px}
.out-box{background:var(--bg);border:1px dashed var(--line);border-radius:10px;padding:12px;min-height:48px;white-space:pre-wrap;word-break:break-word}
.list-out{display:flex;flex-direction:column;gap:6px}
.list-out button{text-align:left;background:#fff;border:1px solid var(--line);border-radius:10px;padding:.55em .8em;font-size:1.05rem;cursor:pointer}
.list-out button:hover{border-color:var(--brand)}
table.tz{width:100%;border-collapse:collapse;font-size:.92rem;margin-top:12px}
table.tz th,table.tz td{border-bottom:1px solid var(--line);padding:.45em .5em;text-align:right}
table.tz th:first-child,table.tz td:first-child{text-align:left}
.tbl-wrap{overflow-x:auto}
/* content */
.prose{font-size:1.02rem}
.prose h2{margin-top:1.8em}
.prose table{width:100%;border-collapse:collapse;margin:1em 0}
.prose th,.prose td{border:1px solid var(--line);padding:.5em .6em;text-align:left}
.prose code{background:var(--brand-soft);padding:.1em .35em;border-radius:5px}
.formula{background:#0f172a;color:#e2e8f0;border-radius:10px;padding:12px 14px;font-family:ui-monospace,Consolas,monospace;overflow-x:auto}
.faq details{background:#fff;border:1px solid var(--line);border-radius:12px;padding:12px 16px;margin-bottom:8px}
.faq summary{font-weight:600;cursor:pointer}
.side-box{background:#fff;border:1px solid var(--line);border-radius:var(--r);padding:16px;position:sticky;top:80px}
.side-box h3{margin:0 0 8px;font-size:1rem}
.side-box a{display:block;padding:.35em 0;border-bottom:1px solid var(--bg);font-size:.95rem}
/* share */
.share{display:flex;flex-wrap:wrap;align-items:center;gap:6px;margin:18px 0}
.share-label{font-weight:600;font-size:.9rem;margin-right:4px}
.sh{border:0;border-radius:8px;padding:.4em .75em;color:#fff;font-size:.85rem;font-weight:600;cursor:pointer;font-family:inherit}
.sh:hover{opacity:.9;text-decoration:none}
.sh-fb{background:#1877f2}.sh-x{background:#000}.sh-wa{background:#16a34a}.sh-li{background:#0a66c2}.sh-pin{background:#e60023}.sh-rd{background:#ff4500}.sh-em{background:#475569}.sh-copy{background:var(--brand)}
/* blog */
.posts{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:16px}
.post-card{background:#fff;border:1px solid var(--line);border-radius:var(--r);overflow:hidden;color:var(--ink);display:flex;flex-direction:column}
.post-card:hover{text-decoration:none;box-shadow:var(--shadow)}
.post-card img,.post-card .ph{aspect-ratio:16/9;object-fit:cover;width:100%}
.post-card .ph{display:grid;place-items:center;background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;font-size:2.5rem;font-weight:800}
.post-card>div{padding:14px}
.hero-img{border-radius:var(--r);margin:10px 0;width:100%}
.tool-cta{display:flex;justify-content:space-between;align-items:center;gap:12px;background:var(--brand-soft);border:1px solid #c7d2fe;border-radius:12px;padding:14px 16px;color:var(--ink);margin:12px 0}
.tool-cta:hover{text-decoration:none;border-color:var(--brand)}
.pager{display:flex;gap:6px;margin:24px 0}
.pager a,.pager span{border:1px solid var(--line);border-radius:8px;padding:.3em .8em;background:#fff}
.pager span{background:var(--brand);color:#fff}
/* forms */
.contact-form{display:grid;gap:12px;max-width:560px}
.contact-form label{display:flex;flex-direction:column;font-weight:600;gap:4px}
.contact-form input,.contact-form textarea{border:1px solid #cfd5e3;border-radius:10px;padding:.65em .75em;font:inherit}
.hp{position:absolute;left:-9999px}
.notice{padding:12px 14px;border-radius:10px}
.notice.ok{background:#ecfdf5;color:var(--ok)}
.notice.err{background:#fef2f2;color:var(--err)}
.btn.sm{padding:.45em .85em;font-size:.88rem;white-space:nowrap}
.install-btn{flex:none}
.pwa-banner{position:fixed;left:12px;right:12px;bottom:12px;z-index:50;max-width:520px;margin:0 auto;display:flex;align-items:center;gap:12px;background:#fff;border:1px solid var(--line);border-radius:16px;padding:12px 14px;box-shadow:0 10px 30px rgba(15,23,42,.18)}
.pwa-banner[hidden]{display:none}
.pwa-banner img{border-radius:10px;flex:none}
.pwa-text{display:flex;flex-direction:column;flex:1;min-width:0;font-size:.9rem;line-height:1.35}
.pwa-text span{color:var(--muted)}
.pwa-close{background:none;border:0;font-size:1.5rem;line-height:1;color:var(--muted);cursor:pointer;padding:0 4px}
@media(display-mode:standalone){.install-btn{display:none!important}body{padding-bottom:env(safe-area-inset-bottom)}}
.ad{margin:18px auto;text-align:center;min-height:0;overflow:hidden}
/* footer */
.foot{background:#0f172a;color:#cbd5e1;margin-top:48px;padding:36px 0 18px}
.foot .logo{color:#fff}
.foot .cols{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:24px}
@media(max-width:760px){.foot .cols{grid-template-columns:1fr 1fr}}
.foot h4{color:#fff;margin:0 0 8px}
.foot a{display:block;color:#cbd5e1;font-size:.92rem;padding:.15em 0}
.foot .muted{color:#94a3b8}
.copy{border-top:1px solid #1e293b;margin-top:24px;padding-top:14px;font-size:.85rem;color:#94a3b8}