:root {
    color-scheme: light;
    --text: #101828;
    --muted: #475569;
    --rule: #e7edf5;
    --input-border: #c4cfde;
    --blue: #1459f5;
    --blue-hover: #1048cc;
    --blue-light: #edf3ff;
    --error: #a32b35;
    --sans: Inter, system-ui, "PingFang SC", "Microsoft YaHei", sans-serif;
    --mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Consolas, monospace;
    --width: 58rem;
    --gutter: clamp(1.1rem, 4vw, 2rem);
}
* { box-sizing: border-box; }
body {
    margin: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    color: var(--text);
    background: white;
    font: 1rem/1.65 var(--sans);
}
.shell { width: min(calc(100% - 2 * var(--gutter)), var(--width)); margin-inline: auto; }
a { color: var(--blue); text-underline-offset: .24em; }
.site-header { border-bottom: 1px solid var(--rule); }
.header-inner {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    min-height: 4rem;
}
.brand, .footer-brand { color: var(--text); font-weight: 800; letter-spacing: -.06em; text-decoration: none; }
.brand { font-size: 1.65rem; justify-self: start; }
.brand span { color: var(--blue); }
nav { display: flex; align-items: center; flex-wrap: wrap; gap: clamp(.55rem, 2.5vw, 1.8rem); }
nav a { color: var(--muted); text-decoration: none; font-size: .9rem; }
nav a:hover, nav a[aria-current] { color: var(--blue); }
.site-header nav a { position: relative; display: flex; align-items: center; min-height: 4rem; white-space: nowrap; }
.site-header nav a[aria-current] { font-weight: 700; }
.site-header nav a[aria-current]::after {
    content: "";
    position: absolute;
    inset: auto 0 -1px;
    height: 2px;
    background: var(--blue);
}
main { flex: 1; padding-block: clamp(1.75rem, 4vw, 3rem) 3rem; overflow-wrap: anywhere; }
h1 { margin: 0; font-size: clamp(2rem, 5vw, 3.35rem); line-height: 1.13; letter-spacing: -.055em; font-weight: 780; }
h2 { margin: 0 0 .8rem; font-size: 1.35rem; line-height: 1.25; letter-spacing: -.025em; }
h3 { margin: 0 0 .55rem; font-size: .875rem; font-weight: 700; }
.intro { margin: .65rem 0 1.6rem; color: var(--muted); font-size: clamp(.95rem, 2vw, 1.12rem); }
.tool-page > h1, .tool-page > .intro { text-align: center; }

.lookup-form { max-width: 44rem; margin-inline: auto; }
label { display: block; margin-bottom: .32rem; font-size: .83rem; font-weight: 650; color: var(--muted); }
.controls { display: flex; align-items: stretch; gap: .55rem; }
input, select, button {
    min-height: 3.1rem;
    padding: .55rem .85rem;
    border: 1px solid var(--input-border);
    border-radius: .55rem;
    color: inherit;
    background: white;
    font: inherit;
}
input { flex: 1 1 0; min-width: 0; }
input::placeholder { color: var(--muted); }
input[aria-invalid="true"] { border-color: var(--error); }
select { padding-inline: .55rem; font: 600 .875rem var(--mono); }
button {
    padding-inline: clamp(.8rem, 3vw, 1.45rem);
    background: var(--blue);
    border-color: var(--blue);
    color: white;
    font-weight: 700;
    cursor: pointer;
    white-space: nowrap;
}
button:hover { background: var(--blue-hover); }
button:disabled { opacity: .65; cursor: wait; }
:focus-visible { outline: 2px solid var(--blue); outline-offset: 2px; }
.network-action { text-align: center; }
.notice { margin: .5rem 0 0; color: var(--muted); font-size: .9rem; }
.notice:empty { margin: 0; }
.notice.is-error { color: var(--error); }

.results { margin-top: clamp(1.65rem, 4vw, 2.7rem); border-top: 1px solid var(--rule); padding-top: 1.15rem; }
.result-heading { display: flex; flex-wrap: wrap; align-items: baseline; gap: .4rem .75rem; margin-bottom: 1.05rem; }
.result-heading h2 { min-width: 0; margin: 0; }
.result-kicker { margin-bottom: 1.05rem; padding-inline-start: .65rem; border-inline-start: 3px solid var(--blue); font-size: .875rem; font-weight: 700; line-height: 1.25; }
.result-count { margin-inline-start: auto; font-size: .875rem; color: var(--muted); }
.ip-address { font: 750 clamp(1.7rem, 5vw, 3.1rem)/1.15 var(--mono); letter-spacing: -.07em; }
.ip-version { padding: .15rem .55rem; border-radius: 2rem; background: var(--blue-light); color: #1744a2; font: 650 .8rem/1.6 var(--mono); }
.result-groups { display: grid; grid-template-columns: 1fr 1fr; gap: 1.3rem 2rem; }
.result-groups > div { min-width: 0; }
.result-groups > div + div { border-inline-start: 1px solid var(--rule); padding-inline-start: 2rem; }
.result { display: grid; grid-template-columns: minmax(6.35rem, 29%) minmax(0, 1fr); gap: .55rem .8rem; margin: 0; }
dt { color: var(--muted); font-size: .875rem; }
dd { margin: 0; font-weight: 550; }
.asn-value { color: #1744a2; font-family: var(--mono); }
dd ul, .records { margin: 0; padding: 0; list-style: none; }
.records li { padding-block: .6rem; border-bottom: 1px solid var(--rule); }
.record-meta { display: block; margin-top: .1rem; color: var(--muted); font-size: .82rem; }
code { font-family: var(--mono); }
pre { white-space: pre-wrap; }
[hidden] { display: none !important; }
.site-footer { border-top: 1px solid var(--rule); }
.footer-inner { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: .6rem 1.2rem; min-height: 3.8rem; padding-block: .75rem; }
.footer-inner nav a { font-size: .83rem; }

@media (max-width: 38rem) {
    .header-inner { grid-template-columns: 1fr; padding-top: .45rem; }
    .site-header nav a { min-height: 2.3rem; }
    .result-groups { grid-template-columns: minmax(0, 1fr); }
    .result-groups > div + div { border-inline-start: 0; padding-inline-start: 0; }
}