:root {
    --ink: #11182f;
    --muted: #667085;
    --paper: #ffffff;
    --canvas: #eef1f6;
    --line: #d7dce6;
    --accent: #b32735;
    --people: #314b7b;
    --intent: #7c2e52;
    --actions: #176b61;
    --time: #8c4c22;
    --place: #5a477d;
    --logic: #6d3c73;
    --status: #6b641f;
    --urgent: #8d2432;
    --food: #8a4e18;
    --health: #9a3b28;
    --travel: #2e6471;
    --work: #425d3d;
    --radius: 18px;
    --shadow: 0 14px 40px rgba(17, 24, 47, .09);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    min-height: 100vh;
    color: var(--ink);
    background: var(--canvas);
    font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif;
    -webkit-font-smoothing: antialiased;
}
a { color: inherit; }
button, select { font: inherit; }

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    display: flex;
    justify-content: space-between;
    align-items: center;
    min-height: 74px;
    padding: 12px clamp(18px, 4vw, 52px);
    background: rgba(255,255,255,.94);
    border-bottom: 1px solid rgba(215,220,230,.9);
    backdrop-filter: blur(14px);
}
.brand { display: flex; align-items: center; gap: 12px; text-decoration: none; }
.brand-mark {
    display: grid; place-items: center; width: 44px; height: 44px;
    border-radius: 13px; color: #fff; background: var(--ink); font-weight: 800; letter-spacing: -.04em;
}
.brand strong, .brand small { display: block; }
.brand strong { font-size: 15px; }
.brand small { margin-top: 2px; color: var(--muted); font-size: 11px; }
.change-link { color: var(--accent); font-weight: 750; text-decoration: none; font-size: 14px; }

main { width: min(1320px, 100%); margin: 0 auto; padding: clamp(24px, 5vw, 64px) clamp(16px, 4vw, 52px) 72px; }
.hero { max-width: 900px; margin: 5vh auto 0; }
.eyebrow { margin: 0 0 12px; color: var(--accent); font-size: 12px; font-weight: 800; letter-spacing: .12em; text-transform: uppercase; }
.hero h1, .sheet-heading h1 { margin: 0; letter-spacing: -.055em; line-height: .98; }
.hero h1 { max-width: 820px; font-size: clamp(42px, 8vw, 82px); }
.intro { max-width: 690px; margin: 24px 0 34px; color: var(--muted); font-size: clamp(17px, 2.2vw, 21px); line-height: 1.55; }

.language-picker {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
    gap: 14px;
    padding: clamp(18px, 3vw, 28px);
    border: 1px solid var(--line);
    border-radius: 24px;
    background: var(--paper);
    box-shadow: var(--shadow);
}
.language-picker label { min-width: 0; }
.language-picker label > span { display: block; margin: 0 0 8px 3px; color: var(--muted); font-size: 12px; font-weight: 750; text-transform: uppercase; letter-spacing: .06em; }
.language-picker select {
    width: 100%; min-height: 58px; padding: 0 16px;
    color: var(--ink); border: 1px solid var(--line); border-radius: 14px; background: #f9fafc;
    font-size: 17px; font-weight: 700;
}
.swap-button {
    align-self: end; width: 58px; height: 58px; border: 1px solid var(--line); border-radius: 50%;
    color: var(--accent); background: #fff; cursor: pointer; font-size: 24px;
}
.primary-button {
    grid-column: 1 / -1; min-height: 60px; margin-top: 4px; padding: 0 22px;
    border: 0; border-radius: 15px; color: #fff; background: var(--ink);
    cursor: pointer; font-weight: 800; font-size: 16px;
}
.primary-button span { margin-left: 8px; color: #ffb4bc; }
.language-list { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 20px; }
.language-list span { padding: 8px 11px; border: 1px solid var(--line); border-radius: 99px; background: rgba(255,255,255,.55); color: var(--muted); font-size: 12px; }

.sheet-heading { margin-bottom: 24px; }
.sheet-heading h1 { font-size: clamp(36px, 6vw, 68px); }
.sheet-heading h1 span { color: var(--accent); }
.sheet-heading > p:last-child { max-width: 680px; margin: 18px 0 0; color: var(--muted); line-height: 1.55; }
.category-nav {
    display: flex; gap: 8px; overflow-x: auto; margin: 0 -4px 24px; padding: 4px 4px 10px;
    scrollbar-width: thin;
}
.category-nav a { flex: 0 0 auto; padding: 10px 13px; border: 1px solid var(--line); border-radius: 99px; background: #fff; text-decoration: none; font-size: 12px; font-weight: 700; }
.kernel-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; align-items: start; }
.kernel-card { --category-color: var(--people); overflow: hidden; scroll-margin-top: 92px; border: 1px solid var(--line); border-top: 7px solid var(--category-color); border-radius: var(--radius); background: var(--paper); box-shadow: var(--shadow); }
.category-intent { --category-color: var(--intent); }
.category-actions { --category-color: var(--actions); }
.category-time { --category-color: var(--time); }
.category-place_direction { --category-color: var(--place); }
.category-questions_logic { --category-color: var(--logic); }
.category-status_qualities { --category-color: var(--status); }
.category-social_emergency { --category-color: var(--urgent); }
.category-food_drink { --category-color: var(--food); }
.category-health { --category-color: var(--health); }
.category-travel { --category-color: var(--travel); }
.category-work { --category-color: var(--work); }

.category-heading {
    display: grid; grid-template-columns: auto minmax(0, 1fr) auto auto; gap: 12px; align-items: center;
    width: 100%; padding: 17px 18px; border: 0; color: inherit; background: transparent; text-align: left; cursor: pointer;
}
.category-number { display: grid; place-items: center; width: 32px; height: 32px; border-radius: 10px; color: #fff; background: var(--category-color); font-size: 11px; font-weight: 850; }
.category-titles strong, .category-titles small { display: block; }
.category-titles strong { font-size: 16px; }
.category-titles small { margin-top: 3px; color: var(--muted); font-size: 11px; }
.item-count { color: var(--muted); font-size: 11px; font-weight: 800; }
.chevron { transition: transform .2s ease; font-size: 20px; }
.category-content { border-top: 1px solid var(--line); }
.term-header, .term-row { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); column-gap: 16px; }
.term-header { padding: 10px 18px; color: var(--muted); background: #f7f8fb; font-size: 10px; font-weight: 800; letter-spacing: .08em; text-transform: uppercase; }
.term-row { position: relative; padding: 11px 18px; border-top: 1px solid #edf0f5; line-height: 1.28; }
.term-row:first-child { border-top: 0; }
.source-term { color: #4d5668; font-size: 14px; }
.target-term { font-size: 15px; font-weight: 800; }
.usage-note { grid-column: 2; margin-top: 4px; color: var(--muted); font-size: 11px; line-height: 1.35; }
.kernel-card.is-collapsed .category-content { display: none; }
.kernel-card.is-collapsed .chevron { transform: rotate(-90deg); }
.floating-change { display: none; }

.site-footer { display: flex; justify-content: space-between; gap: 12px; padding: 24px clamp(18px,4vw,52px); color: var(--muted); border-top: 1px solid var(--line); background: #fff; font-size: 11px; }

@media (max-width: 760px) {
    .site-header { min-height: 66px; }
    .brand small { display: none; }
    .change-link { display: none; }
    main { padding-top: 32px; }
    .hero { margin-top: 1vh; }
    .language-picker { grid-template-columns: 1fr auto; }
    .language-picker label { grid-column: 1 / -1; }
    .swap-button { grid-column: 2; grid-row: 2; margin-top: -72px; z-index: 2; width: 48px; height: 48px; }
    .language-picker label:nth-of-type(2) { margin-top: 4px; }
    .kernel-grid { grid-template-columns: 1fr; gap: 14px; }
    .category-nav { position: sticky; top: 66px; z-index: 10; margin-right: -16px; margin-left: -16px; padding: 10px 16px; background: rgba(238,241,246,.95); backdrop-filter: blur(12px); }
    .category-heading { padding: 15px 14px; }
    .term-header, .term-row { padding-right: 14px; padding-left: 14px; }
    .floating-change { position: fixed; right: 18px; bottom: max(18px, env(safe-area-inset-bottom)); z-index: 30; display: grid; place-items: center; width: 54px; height: 54px; border-radius: 50%; color: #fff; background: var(--accent); box-shadow: 0 10px 28px rgba(141,36,50,.32); text-decoration: none; font-size: 22px; }
    .site-footer { padding-bottom: 86px; }
}

@media print {
    body { background: #fff; }
    .site-header, .category-nav, .floating-change, .site-footer { display: none !important; }
    main { max-width: none; padding: 0; }
    .sheet-heading { margin: 0 0 8mm; }
    .sheet-heading h1 { font-size: 28pt; }
    .kernel-grid { display: block; }
    .kernel-card { break-inside: avoid; margin-bottom: 5mm; box-shadow: none; }
    .category-content { display: block !important; }
}

/* v0.2 onboarding */
.onboarding { max-width: 1040px; margin: clamp(24px, 7vh, 90px) auto 70px; }
.onboarding h1 { max-width: 900px; margin: 18px 0 14px; font-size: clamp(42px, 7vw, 82px); line-height: .98; letter-spacing: -.065em; }
.welcome-rotator { height: clamp(70px, 10vw, 112px); overflow: hidden; margin-top: 16px; }
.welcome-track { display: flex; flex-direction: column; transform: translateY(0); transition: transform .7s cubic-bezier(.22,.8,.22,1); }
.welcome-track span { display: flex; align-items: center; height: clamp(70px, 10vw, 112px); color: var(--accent); font-size: clamp(54px, 9vw, 104px); font-weight: 900; line-height: 1; letter-spacing: -.07em; }
.multilingual-intro { display: flex; flex-wrap: wrap; gap: 6px 10px; }
.language-cards { display: grid; grid-template-columns: repeat(5, minmax(0,1fr)); gap: 12px; margin-top: 34px; }
.language-card { position: relative; min-height: 170px; padding: 20px; overflow: hidden; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; box-shadow: var(--shadow); text-decoration: none; transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease; }
.language-card:hover, .language-card:focus-visible { transform: translateY(-5px); border-color: var(--accent); box-shadow: 0 20px 45px rgba(17,24,47,.14); outline: none; }
.language-code { display: inline-flex; padding: 5px 8px; border-radius: 99px; color: var(--accent); background: #fff0f1; font-size: 10px; font-weight: 900; letter-spacing: .12em; }
.language-card strong, .language-card small { display: block; }
.language-card strong { margin-top: 26px; font-size: clamp(20px,2.3vw,30px); letter-spacing: -.035em; }
.language-card small { margin-top: 5px; color: var(--muted); }
.card-arrow { position: absolute; right: 18px; bottom: 15px; color: var(--accent); font-size: 25px; transition: transform .18s ease; }
.language-card:hover .card-arrow { transform: translateX(5px); }
.chosen-source { display: inline-flex; flex-direction: column; gap: 3px; padding: 12px 16px; border: 1px solid var(--line); border-radius: 13px; background: #fff; box-shadow: var(--shadow); }
.chosen-source span { color: var(--muted); font-size: 10px; font-weight: 800; letter-spacing: .08em; text-transform: uppercase; }
.chosen-source strong { font-size: 18px; }
.target-step h1 { font-size: clamp(40px,6vw,72px); }
.same-language { opacity: .72; }
.back-link { display: inline-flex; margin-top: 24px; color: var(--accent); font-size: 13px; font-weight: 800; text-decoration: none; }

@media (max-width: 900px) { .language-cards { grid-template-columns: repeat(2,minmax(0,1fr)); } .language-card:last-child { grid-column: 1 / -1; } }
@media (max-width: 560px) {
    .onboarding { margin-top: 18px; }
    .welcome-rotator { margin-top: 4px; }
    .onboarding h1 { font-size: clamp(38px,13vw,58px); }
    .language-cards { grid-template-columns: 1fr; margin-top: 25px; }
    .language-card, .language-card:last-child { grid-column: auto; min-height: 108px; }
    .language-card strong { margin-top: 15px; }
}