:root{--ink:#172033;--muted:#667085;--line:#e4e8ef;--panel:#fff;--bg:#f6f8fb;--accent:#1769e0;--navy:#10203b;--soft:#eef5ff;--green:#215e46}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;background:var(--bg);color:var(--ink);line-height:1.55}.wrap{max-width:1120px;margin:auto;padding:0 20px}a{color:var(--accent)}.top{background:var(--navy);color:#fff}.nav{min-height:68px;display:flex;align-items:center;justify-content:space-between;gap:22px}.brand{font-weight:850;font-size:22px;letter-spacing:-.03em;color:#fff;text-decoration:none}.brand span{color:#69a5ff}.navlinks{display:flex;align-items:center;gap:22px}.navlinks a{color:#dbe7ff;text-decoration:none;font-size:14px}.hero{padding:62px 0 48px;background:linear-gradient(180deg,#10203b,#173763);color:#fff}.hero.compact{padding:42px 0 34px}.hero h1{font-size:clamp(38px,5vw,62px);line-height:1.02;letter-spacing:-.05em;margin:0 0 16px;max-width:900px}.hero.compact h1{font-size:clamp(34px,4.5vw,52px)}.hero p{max-width:760px;color:#d8e4f7;font-size:18px;margin:0}.kicker{text-transform:uppercase;letter-spacing:.12em;font-weight:800;font-size:12px;color:#9fc4ff;margin-bottom:12px}.searchbox{margin-top:28px;max-width:680px;display:flex;background:#fff;border-radius:13px;padding:6px;box-shadow:0 14px 38px rgba(0,0,0,.15)}.searchbox input{border:0;outline:0;flex:1;padding:13px 14px;font-size:16px;border-radius:10px}.searchbox button{border:0;border-radius:9px;background:var(--accent);color:#fff;padding:0 20px;font-weight:750}.ad{min-height:100px;border:1px dashed #c7cfdb;background:#fff;margin:26px auto;border-radius:10px;display:flex;align-items:center;justify-content:center;color:#8993a3;font-size:11px;text-transform:uppercase;letter-spacing:.1em}.section{padding:38px 0}.sectionhead{display:flex;align-items:end;justify-content:space-between;gap:20px;margin-bottom:20px}.sectionhead h2{font-size:28px;letter-spacing:-.03em;margin:0}.sectionhead p{color:var(--muted);margin:4px 0 0}.toolgrid,.catgrid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.tool,.category,.card{background:#fff;border:1px solid var(--line);border-radius:16px;box-shadow:0 8px 30px rgba(16,32,59,.045)}.tool{padding:22px;text-decoration:none;color:inherit;transition:.18s ease}.tool:hover{transform:translateY(-2px);border-color:#b9d2f6;box-shadow:0 12px 32px rgba(16,32,59,.08)}.tool .icon,.category .icon{width:42px;height:42px;border-radius:11px;background:var(--soft);display:grid;place-items:center;font-size:20px;margin-bottom:16px}.tool h3,.category h3{margin:0 0 6px;font-size:18px}.tool p,.category p{margin:0;color:var(--muted);font-size:14px}.tag{display:inline-block;margin-top:14px;font-size:11px;font-weight:800;text-transform:uppercase;letter-spacing:.08em;color:var(--accent)}.category{padding:22px}.coming{opacity:.72}.grid{display:grid;grid-template-columns:1.02fr .98fr;gap:22px;margin:28px 0}.card{padding:24px}h2{margin:0 0 18px;font-size:22px}.sub,.small{font-size:13px;color:var(--muted)}.sub{margin-top:-12px}.fields{display:grid;grid-template-columns:1fr 1fr;gap:16px}.field label{display:block;font-size:13px;font-weight:700;margin-bottom:7px}.field input,.field select{width:100%;height:48px;border:1px solid #ccd3df;border-radius:10px;padding:0 13px;font-size:16px;background:#fff}.result{background:#f7fbff;border:1px solid #d8e8ff;border-radius:14px;padding:20px;margin-bottom:14px}.eyebrow{font-size:12px;text-transform:uppercase;letter-spacing:.1em;font-weight:800;color:var(--muted)}.big{font-size:clamp(34px,5vw,48px);font-weight:850;letter-spacing:-.045em}.rows{display:grid;gap:11px;margin-top:18px}.row{display:flex;justify-content:space-between;gap:20px;border-bottom:1px solid var(--line);padding-bottom:9px;font-size:14px}.splitbar,.stack{height:16px;border-radius:99px;overflow:hidden;background:#e8edf4;display:flex;margin:10px 0}.principal,.stack .p{background:var(--accent)}.interest,.stack .i{background:#9db9df}.legend{display:flex;justify-content:space-between;gap:14px;flex-wrap:wrap;font-size:13px;color:var(--muted)}.saving{margin-top:16px;padding:14px;border-radius:12px;background:#f2fbf7;border:1px solid #d7eee3;color:var(--green);font-size:14px}.info{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin:26px 0}.info p{color:var(--muted);font-size:14px}.faq{margin:30px 0}.faq details{background:#fff;border:1px solid var(--line);border-radius:10px;padding:15px 17px;margin:10px 0}.disclaimer{font-size:12px;color:var(--muted);padding:20px 0 45px}.footer{font-size:13px;color:var(--muted);border-top:1px solid var(--line);padding:28px 0 42px;background:#fff}.footerin{display:flex;justify-content:space-between;gap:24px;flex-wrap:wrap}.footerlinks{display:flex;gap:18px;flex-wrap:wrap}.footer a{color:var(--muted);text-decoration:none}.chartcard{margin:0 0 28px}.charthead{display:flex;justify-content:space-between;gap:18px;align-items:flex-start;flex-wrap:wrap}.chartstats{display:flex;gap:22px;flex-wrap:wrap}.chartstat span{display:block;font-size:12px;color:var(--muted)}.chartstat b{font-size:18px}.chartwrap{position:relative;height:340px;margin-top:20px}.chartwrap canvas{width:100%;height:100%;display:block}.chartlegend{display:flex;gap:18px;flex-wrap:wrap;margin-top:14px;font-size:13px;color:var(--muted)}.key{display:inline-block;width:18px;height:3px;vertical-align:middle;margin-right:7px;border-radius:3px}.key.standard{background:#9db9df}.key.extra{background:#1769e0}.tooltip{position:absolute;display:none;pointer-events:none;background:#10203b;color:#fff;padding:10px 12px;border-radius:9px;font-size:12px;box-shadow:0 8px 22px rgba(0,0,0,.18);white-space:nowrap;z-index:2}.breakdown{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin-top:26px}.mini h3{margin:0 0 5px;font-size:16px}.minirow{display:flex;justify-content:space-between;font-size:13px;color:var(--muted)}.prose{max-width:820px;padding:40px 0 70px}.prose h2{margin-top:32px}.prose p,.prose li{color:#475467}.crumb{font-size:13px;color:#d8e4f7;margin-bottom:12px}.crumb a{color:#d8e4f7}.note{padding:16px 18px;border:1px solid #d8e8ff;background:#f7fbff;border-radius:12px;color:#344054}.empty-search{display:none;margin-top:18px;color:var(--muted)}
@media(max-width:760px){.navlinks a:not(:last-child){display:none}.hero{padding:42px 0 34px}.grid,.fields,.info,.breakdown,.toolgrid,.catgrid{grid-template-columns:1fr}.chartwrap{height:270px}.card{padding:19px}.wrap{padding:0 15px}.searchbox button{padding:0 14px}.sectionhead{align-items:flex-start;flex-direction:column}.ad{min-height:90px}}

.calc-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(280px,.8fr);gap:24px;align-items:start}
.calc-panel,.result-panel{background:#fff;border:1px solid var(--border,#dce3eb);border-radius:18px;padding:24px}
.field{display:grid;gap:7px;margin-bottom:16px}.field label{font-weight:700;font-size:.92rem}
.field input,.field select{width:100%;box-sizing:border-box;padding:12px 13px;border:1px solid #cbd5e1;border-radius:10px;font:inherit;background:#fff}
.result-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.result-box{background:#f7f9fc;border-radius:12px;padding:14px}.result-box span{display:block;color:#64748b;font-size:.78rem;margin-bottom:4px}.result-box b{font-size:1.12rem;overflow-wrap:anywhere}
.tool-intro{max-width:760px}.tool-intro h1{margin-bottom:8px}.formula-note{font-size:.88rem;color:#64748b;margin-top:16px}
.tool-cards{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.tool-card{display:block;text-decoration:none;color:inherit;border:1px solid #dce3eb;border-radius:16px;padding:18px;background:#fff}.tool-card:hover{border-color:#94a3b8}.tool-card small{color:#64748b}
@media(max-width:760px){.calc-grid{grid-template-columns:1fr}.tool-cards{grid-template-columns:1fr}.result-grid{grid-template-columns:1fr 1fr}}

/* v0.3 shared calculator framing */
.toolpage{padding:34px 0 56px}.tool-intro{max-width:760px;margin-bottom:24px}.tool-intro h1{font-size:clamp(34px,4.5vw,52px);line-height:1.06;letter-spacing:-.045em;margin:0 0 12px}.tool-intro>p:last-child{color:var(--muted);font-size:17px}.ad-slot{min-height:100px;border:1px dashed #c7cfdb;background:#fff;margin:26px auto;border-radius:10px;display:flex;align-items:center;justify-content:center;color:#8993a3;font-size:11px;text-transform:uppercase;letter-spacing:.1em}.more-tools{margin-top:34px}.category-link{display:block;text-decoration:none;color:inherit;transition:.18s ease}.category-link:hover{transform:translateY(-2px);border-color:#b9d2f6}.category-link .category-cta{display:inline-block;margin-top:14px;color:var(--accent);font-size:12px;font-weight:800}.category.disabled{opacity:.68}.category.disabled .category-cta{color:var(--muted)}.tool[hidden]{display:none!important}.filter-note{margin:0 0 16px;color:var(--muted);font-size:14px}.filter-note:empty{display:none}
@media(max-width:760px){.toolpage{padding:26px 0 42px}.tool-intro h1{font-size:34px}.result-grid{grid-template-columns:1fr}.ad-slot{min-height:90px}}

/* v0.4 design system */
.searchbox{padding:0}.searchbox input{padding:17px 18px}
.category-v4{background:linear-gradient(145deg,#eaf2ff,#f5f8ff);border:1px solid #cdddf6;position:relative;overflow:hidden}
.category-v4 .icon{background:#fff;border:1px solid #d9e5f7}
.category-v4 .category-cta{display:inline-block;margin-top:16px;font-weight:800;font-size:13px;color:#1557b0}
.category-v4:hover{border-color:#8eb5ee;transform:translateY(-2px)}
.catalog-count{font-size:13px;color:var(--muted);font-weight:700}
.primary-result{background:linear-gradient(145deg,#eef6ff,#f8fbff);border:1px solid #cfe1fa;border-radius:16px;padding:22px;margin-bottom:16px}
.primary-result .eyebrow{color:#4f6f99}.primary-result .big{color:#10203b}
.primary-duo{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-bottom:16px}.primary-duo .primary-result{margin:0}
.helper{display:block;color:var(--muted);font-size:12px;line-height:1.45;margin-top:5px;font-weight:400}
.viz-card{margin:22px 0 28px}.viz-wrap{position:relative;height:310px;margin-top:18px}.viz-wrap canvas{width:100%;height:100%;display:block}
.viz-legend{display:flex;gap:18px;flex-wrap:wrap;color:var(--muted);font-size:13px;margin-top:12px}
.viz-key{width:18px;height:3px;border-radius:3px;display:inline-block;vertical-align:middle;margin-right:6px;background:#1769e0}.viz-key.alt{background:#9db9df}
.more-tools{padding:36px 0 10px}.more-tools h2{margin-bottom:18px}
.tool-cards{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}
.tool-card{display:block;text-decoration:none;color:inherit;border:1px solid var(--line);border-radius:16px;padding:19px;background:#fff;transition:.18s ease}
.tool-card:hover{transform:translateY(-2px);border-color:#b9d2f6;box-shadow:0 10px 25px rgba(16,32,59,.06)}
.tool-card b,.tool-card small{display:block}.tool-card b{font-size:16px;margin-bottom:7px}.tool-card small{color:var(--muted);font-size:13px;line-height:1.45}
.calc-section{margin:24px 0}.calc-section-title{margin-bottom:14px}
.cidr-row{display:grid;grid-template-columns:1fr 150px;gap:12px}
.cidr-visual{display:grid;grid-template-columns:repeat(4,1fr);gap:5px;margin-top:18px}.cidr-octet{background:#f3f6fa;border-radius:8px;padding:10px 6px;text-align:center;font:600 13px ui-monospace,SFMono-Regular,Menlo,monospace}
.category-hero{padding:42px 0 30px}.category-hero h1{font-size:clamp(34px,4.5vw,50px);letter-spacing:-.04em;margin:0 0 10px}.category-hero p{max-width:720px;color:var(--muted)}
@media(max-width:760px){.primary-duo,.cidr-row{grid-template-columns:1fr}.viz-wrap{height:250px}.tool-cards{grid-template-columns:1fr}.cidr-visual{grid-template-columns:1fr 1fr}}

/* v0.5 subnet enhancements */
.binary-panel{margin-top:20px;padding:16px;border:1px solid var(--line);border-radius:14px;background:#f8fafc}
.binary-head{display:flex;justify-content:space-between;gap:12px;align-items:end;margin-bottom:10px}.binary-head h3{margin:0;font-size:15px}.binary-head span{font-size:12px;color:var(--muted)}
.binary-mask{display:flex;gap:6px;flex-wrap:wrap;font:700 13px ui-monospace,SFMono-Regular,Menlo,monospace}
.binary-octet{display:flex;gap:1px;padding:8px 7px;border-radius:8px;background:#fff;border:1px solid #e2e8f0}
.bit.net{color:#1769e0}.bit.host{color:#8795a8}
.bit-legend{display:flex;gap:16px;flex-wrap:wrap;margin-top:10px;font-size:12px;color:var(--muted)}
.bit-dot{display:inline-block;width:9px;height:9px;border-radius:50%;margin-right:5px;background:#1769e0}.bit-dot.host{background:#8795a8}
.ip-status{margin-top:14px;padding:14px 16px;border-radius:12px;background:#f2f7ff;border:1px solid #d6e5fb}.ip-status b{display:block;margin-bottom:3px}.ip-status span{color:var(--muted);font-size:13px}
.rfc-card{margin:22px 0 28px}.rfc-table{width:100%;border-collapse:collapse;margin-top:14px}.rfc-table th,.rfc-table td{text-align:left;padding:12px 10px;border-bottom:1px solid var(--line)}.rfc-table th{font-size:12px;color:var(--muted);text-transform:uppercase;letter-spacing:.04em}.rfc-table code{font-size:13px}
@media(max-width:600px){.binary-head{display:block}.binary-head span{display:block;margin-top:4px}.rfc-table{font-size:13px}.rfc-table th,.rfc-table td{padding:10px 6px}}

/* v0.6 utility components */
.result-note{font-size:13px;color:var(--muted);margin-top:7px}.button-row{display:flex;gap:10px;flex-wrap:wrap;margin-top:14px}.btn{appearance:none;border:0;border-radius:10px;background:var(--accent);color:#fff;padding:11px 16px;font:700 14px inherit;cursor:pointer}.btn.secondary{background:#eef5ff;color:#1557b0;border:1px solid #d4e4fb}.btn:active{transform:translateY(1px)}
.inline-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px}.code-area{width:100%;min-height:280px;resize:vertical;border:1px solid #ccd3df;border-radius:12px;padding:14px;font:14px/1.5 ui-monospace,SFMono-Regular,Menlo,monospace;background:#fff;color:var(--ink)}.status-good{color:#216e4e}.status-bad{color:#b42318}.password-output{font:800 clamp(20px,3vw,30px)/1.35 ui-monospace,SFMono-Regular,Menlo,monospace;overflow-wrap:anywhere}.checkgrid{display:grid;grid-template-columns:1fr 1fr;gap:10px 16px;margin:14px 0}.check{display:flex;align-items:center;gap:8px;font-size:14px}.check input{width:18px;height:18px}.meter{height:10px;border-radius:99px;background:#e8edf4;overflow:hidden;margin-top:12px}.meter>span{display:block;height:100%;background:#1769e0;width:0;transition:width .15s}.swap-row{display:flex;justify-content:center;margin:-4px 0 12px}.swap{border:1px solid #d5deea;background:#fff;border-radius:99px;width:42px;height:42px;cursor:pointer;font-size:18px}.formula{font:600 13px ui-monospace,SFMono-Regular,Menlo,monospace;color:#475467;background:#f8fafc;border:1px solid var(--line);padding:12px;border-radius:10px;margin-top:14px}.segmented{display:flex;gap:6px;flex-wrap:wrap;margin-bottom:18px}.segmented button{border:1px solid #d8e0eb;background:#fff;border-radius:9px;padding:8px 11px;cursor:pointer;font-weight:700;color:#475467}.segmented button.active{background:#eef5ff;border-color:#aac9f4;color:#1557b0}.mini-table{width:100%;border-collapse:collapse}.mini-table td{padding:9px 4px;border-bottom:1px solid var(--line);font-size:14px}.mini-table td:last-child{text-align:right;font-weight:750}.tool-explain{margin:24px 0}.tool-explain h2{margin-bottom:8px}.tool-explain p{color:#475467;max-width:850px}.output-box{background:#0f1e35;color:#e8eef8;border-radius:12px;padding:15px;font:14px/1.55 ui-monospace,SFMono-Regular,Menlo,monospace;white-space:pre-wrap;overflow-wrap:anywhere;min-height:80px}
@media(max-width:760px){.inline-grid,.checkgrid{grid-template-columns:1fr}.code-area{min-height:230px}}