:root{
  --ink:#15191B; --ink-2:#1F2528; --paper:#EEF0EC; --paper-2:#E3E7E1;
  --steel-1:#6B7478; --steel-2:#C9CFCC; --signal:#C8511C; --signal-d:#A9410F;
  --text:#15191B; --mute:#56605D; --line:rgba(21,25,27,.16);
  --on-ink:#EEF0EC; --on-ink-mute:rgba(238,240,236,.64); --line-ink:rgba(238,240,236,.16);
  --serif:"Shippori Mincho B1","Yu Mincho","Hiragino Mincho ProN",serif;
  --sans:"Noto Sans JP","Hiragino Sans",system-ui,sans-serif;
  --gut:clamp(20px,5vw,72px);
  --head-h:68px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;scroll-padding-top:var(--head-h);-webkit-text-size-adjust:100%}
body{background:var(--paper);color:var(--text);font:400 16px/1.95 var(--sans);overflow-x:clip;font-feature-settings:"palt"}
a{color:inherit;text-decoration:none}
img,svg,canvas{display:block;max-width:100%}
h1,h2,h3{font-family:var(--serif);font-weight:700;line-height:1.4;letter-spacing:.03em;word-break:auto-phrase;text-wrap:balance}
p{line-break:strict;text-wrap:pretty}
.wrap{width:100%;max-width:1240px;margin:0 auto;padding-inline:var(--gut)}
:focus-visible{outline:2px solid var(--signal);outline-offset:4px}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%)}

/* 文字サイズ */
.t-h2{font-size:clamp(26px,3.5vw,46px)}
.t-h3{font-size:clamp(19px,1.9vw,24px)}
.t-lead{font-size:clamp(16px,1.35vw,19px);line-height:2}
.t-small{font-size:13px;line-height:1.8;color:var(--mute)}

/* ボタン・リンク */
.btn{
  display:inline-flex;align-items:center;gap:14px;
  background:var(--signal);color:#fff;font-weight:700;font-size:15px;line-height:1.4;
  padding:18px 28px;border-radius:2px;position:relative;overflow:hidden;isolation:isolate;
  transition:transform .2s ease;
}
.btn::before{content:"";position:absolute;inset:0;background:var(--signal-d);transform:translateY(101%);transition:transform .35s cubic-bezier(.2,.7,.2,1);z-index:-1}
.btn:hover::before{transform:none}
.btn:active{transform:scale(.98)}
.btn .ar{display:inline-block;transition:transform .35s cubic-bezier(.2,.7,.2,1)}
.btn:hover .ar{transform:translate(3px,-3px)}
.btn.sm{padding:11px 18px;font-size:13px;gap:8px}
.link{
  font-weight:700;font-size:15px;display:inline-block;padding-bottom:4px;
  background:linear-gradient(currentColor,currentColor) 0 100%/100% 1px no-repeat;
  transition:background-size .35s ease;
}
.link:hover{background-size:0 1px;background-position:100% 100%}

/* ヘッダー */
.head{position:fixed;inset:0 0 auto 0;height:var(--head-h);z-index:50;color:var(--on-ink);transition:background .3s,backdrop-filter .3s}
.head.solid{background:rgba(21,25,27,.97);backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px)}
.head .wrap{height:100%;display:flex;align-items:center;justify-content:space-between;gap:24px}
.logo{font:800 26px/1 var(--serif);letter-spacing:.02em;display:flex;align-items:baseline;gap:14px;white-space:nowrap}
.logo em{font-style:normal}
.logo b{color:var(--signal);font-weight:800}
.logo span{font:500 11px/1 var(--sans);color:var(--on-ink-mute);letter-spacing:.12em}
.nav{display:flex;align-items:center;gap:clamp(16px,2.4vw,34px);font-size:14px;font-weight:500}
.nav a:not(.btn){opacity:.82;transition:opacity .2s}
.nav a:not(.btn):hover{opacity:1}

/* ヒーロー */
.hero{position:relative;background:var(--ink);color:var(--on-ink);min-height:min(100svh,920px);display:flex;flex-direction:column;justify-content:flex-end;overflow:hidden}
.hero-photo{
  position:absolute;inset:0 0 0 42%;
  background:url("/images/knack-hero-no-cloth.png") center/cover no-repeat;
  filter:grayscale(.6) contrast(1.1) brightness(.7);
  -webkit-mask-image:linear-gradient(90deg,transparent 0,#000 62%);mask-image:linear-gradient(90deg,transparent 0,#000 62%);
  transform:scale(1.06);animation:photoIn 2.4s cubic-bezier(.2,.7,.2,1) forwards;
}
.hero::after{content:"";position:absolute;inset:auto 0 0 0;height:46%;background:linear-gradient(transparent,var(--ink) 88%);pointer-events:none}
@keyframes photoIn{from{opacity:0;transform:scale(1.14)}to{opacity:1;transform:scale(1.02)}}
.hero-in{position:relative;z-index:2;padding-top:calc(var(--head-h) + 64px);padding-bottom:clamp(28px,4vw,48px)}
.hero-area{display:flex;align-items:center;gap:14px;font-size:13px;color:var(--on-ink-mute);margin-bottom:clamp(24px,3vw,40px)}
.hero-area::before{content:"";width:32px;height:1px;background:var(--signal)}
.hero h1{font-size:clamp(42px,7.4vw,104px);font-weight:800;line-height:1.22;letter-spacing:.02em}
.hero h1 .ln{display:block;overflow:hidden;padding-bottom:.08em}
.hero h1 .ln i{display:block;font-style:normal;transform:translateY(105%);animation:lineUp 1.1s cubic-bezier(.2,.7,.2,1) forwards}
.hero h1 .ln:nth-child(2) i{animation-delay:.14s}
@keyframes lineUp{to{transform:none}}
.hero-sub{display:grid;grid-template-columns:minmax(0,440px) auto;gap:clamp(24px,5vw,72px);align-items:end;margin-top:clamp(28px,3.4vw,48px)}
.hero-sub p{color:#D5DAD6}
.hero-cta small{display:block;margin-top:12px;font-size:12px;color:var(--on-ink-mute)}
.fade{opacity:0;animation:fadeIn 1s .55s ease forwards}
.fade.d2{animation-delay:.75s}.fade.d3{animation-delay:.95s}
@keyframes fadeIn{to{opacity:1}}
.facts{display:grid;grid-template-columns:repeat(3,1fr);border-top:1px solid var(--line-ink);margin-top:clamp(40px,5vw,72px)}
.facts div{padding:22px 0 0;padding-right:20px}
.facts div+div{padding-left:clamp(16px,2.4vw,32px);border-left:1px solid var(--line-ink)}
.facts dt{font:700 clamp(20px,2.3vw,30px)/1 var(--serif);letter-spacing:.03em;white-space:nowrap;display:flex;align-items:baseline;height:clamp(40px,4.4vw,58px);align-content:flex-end;flex-wrap:wrap}
.facts dt b{font-size:1.8em;font-weight:800;line-height:1;margin-right:.08em;font-feature-settings:"lnum"}
.facts dd{font-size:13px;color:var(--on-ink-mute);margin-top:6px}

/* 研磨帯（番手の進行） */
.grit{background:var(--ink);color:var(--on-ink);height:440vh;position:relative}
.grit-pin{position:sticky;top:0;height:100vh;height:100svh;display:flex;flex-direction:column;justify-content:center;padding-top:var(--head-h);overflow:hidden}
.grit-top{display:flex;justify-content:space-between;align-items:end;gap:32px;margin-bottom:clamp(18px,2.6vh,32px)}
.grit-top h2{font-size:clamp(24px,3.2vw,44px)}
.grit-top p{max-width:380px;font-size:14px;line-height:1.9;color:var(--on-ink-mute)}
.plate{background:#c9cecb;position:relative;height:clamp(200px,44vh,460px);border-radius:2px;overflow:hidden;background:#3d4447;box-shadow:0 0 0 1px rgba(255,255,255,.08),0 40px 80px -40px #000}
.plate canvas{width:100%;height:100%}
.plate-read{position:absolute;left:clamp(16px,2.4vw,32px);bottom:clamp(14px,2vw,26px);display:flex;align-items:baseline;gap:18px;color:#fff;text-shadow:0 2px 28px rgba(0,0,0,.75);pointer-events:none;transition:color .5s,text-shadow .5s}
.plate-read.ink{color:var(--ink);text-shadow:0 1px 24px rgba(255,255,255,.7)}
.plate-read{flex-wrap:wrap;gap:6px 18px}
.plate-read b{font:800 clamp(26px,4.6vw,64px)/1.2 var(--serif);letter-spacing:.01em;font-feature-settings:"lnum"}
.plate-read span{font:700 clamp(14px,1.4vw,18px)/1.4 var(--sans)}
.plate-read.swap b,.plate-read.swap span{animation:swap .5s cubic-bezier(.2,.7,.2,1)}
@keyframes swap{from{opacity:0;transform:translateY(14px)}to{opacity:1;transform:none}}
.scale{position:relative;margin-top:clamp(18px,2.6vh,30px)}
.scale-bar{height:1px;background:var(--line-ink);position:relative}
.scale-bar i{position:absolute;inset:0;background:var(--signal);transform-origin:0 50%;transform:scaleX(var(--p,0))}
.scale ol{list-style:none;display:grid;grid-template-columns:repeat(3,1fr);margin-top:0}
.scale li{position:relative;padding-top:16px;font-size:13px;color:var(--on-ink-mute);transition:color .3s}
.scale li::before{content:"";position:absolute;left:0;top:-4px;width:1px;height:9px;background:currentColor}
.scale li b{display:block;font:700 15px/1.5 var(--serif);letter-spacing:.04em;font-feature-settings:"lnum"}
.scale li.on{color:var(--on-ink)}
.scale li.on::before{background:var(--signal);width:2px}
.grit-note{margin-top:clamp(14px,2vh,22px);font-size:12px;color:var(--on-ink-mute)}

/* セクション共通 */
.sec{padding-block:clamp(72px,10vw,150px)}
.sec + .sec{border-top:1px solid var(--line)}
.cols{display:grid;grid-template-columns:minmax(0,5fr) minmax(0,7fr);gap:clamp(32px,6vw,96px);align-items:start}
.sec-head p{margin-top:20px;color:var(--mute)}

/* こんなときに */
.cases{list-style:none}
.cases li{font:700 clamp(19px,2.3vw,30px)/1.5 var(--serif);letter-spacing:.03em;padding:clamp(20px,2.4vw,30px) 0;border-bottom:1px solid var(--line);display:flex;align-items:center;position:relative}
.cases li:first-child{border-top:1px solid var(--line)}
.cases li::before{content:"";flex:none;width:0;height:1px;background:var(--signal);transition:width .5s cubic-bezier(.2,.7,.2,1)}
.cases li::before{margin-right:0;transition:width .5s cubic-bezier(.2,.7,.2,1),margin .5s cubic-bezier(.2,.7,.2,1)}
.cases li:hover::before{width:36px;margin-right:20px}

/* 磨き */
.bore{margin-top:clamp(36px,5vw,64px);display:grid;grid-template-columns:repeat(2,1fr);gap:1px;background:var(--line);border:1px solid var(--line)}
.bore figure{background:var(--paper);padding:clamp(20px,3vw,40px)}
.bore figcaption{font-size:14px;font-weight:700;margin-bottom:18px;display:flex;gap:12px;align-items:baseline}
.bore figcaption span{font:700 13px var(--serif);color:var(--signal);font-feature-settings:"lnum"}
.bore svg{width:100%;height:auto}
.key{display:flex;align-items:center;gap:10px;font-size:13px;color:var(--mute);margin-top:16px}
.key i{width:28px;height:3px;background:var(--signal)}
.works{list-style:none;display:grid;grid-template-columns:repeat(3,1fr);margin-top:clamp(28px,4vw,48px);border-top:1px solid var(--line)}
.works li{padding:22px 20px 0 0;font:700 clamp(17px,1.7vw,21px)/1.5 var(--serif);letter-spacing:.03em}
.works li+li{padding-left:clamp(16px,2vw,28px);border-left:1px solid var(--line)}
.after{display:flex;justify-content:space-between;align-items:center;gap:20px;flex-wrap:wrap;margin-top:clamp(28px,4vw,44px)}

/* 磨き以外 */
.svc{display:grid;grid-template-columns:minmax(0,5fr) minmax(0,7fr);gap:clamp(24px,6vw,96px);padding-block:clamp(32px,4.4vw,56px);border-top:1px solid var(--line)}
.svc:last-child{border-bottom:1px solid var(--line)}
.svc h3{font-size:clamp(22px,2.6vw,34px)}
.svc .area{display:inline-block;margin-top:14px;font-size:13px;font-weight:700;color:var(--signal)}
.svc .lead{font-weight:700;font-size:clamp(16px,1.4vw,18px);margin-bottom:14px}
.svc p+p{margin-top:10px}
.svc .muted{color:var(--mute);font-size:15px}
.ops{list-style:none;display:flex;flex-wrap:wrap;gap:10px 0;margin:18px 0;counter-reset:o}
.ops li{font-size:14px;font-weight:700;display:flex;align-items:center}
.ops li+li::before{content:"";width:28px;height:1px;background:var(--steel-1);margin-inline:14px}
.svc .link{margin-top:18px}

/* Knackについて */
.about{background:var(--paper-2)}
.years{display:flex;align-items:baseline;white-space:nowrap;font-family:var(--serif);font-weight:800;line-height:1;margin-top:10px;color:var(--ink)}
.years b{font-size:clamp(120px,17vw,250px);letter-spacing:-.02em;font-feature-settings:"lnum";font-weight:800}
.years span{font-size:clamp(30px,4.2vw,62px);margin-left:.14em;letter-spacing:.04em}
.about-lead{font:700 clamp(22px,2.6vw,34px)/1.5 var(--serif);letter-spacing:.03em}
.about p{margin-bottom:16px}
.spec{margin-top:clamp(28px,4vw,44px);border-top:1px solid var(--line)}
.spec div{display:grid;grid-template-columns:9em 1fr;gap:16px;padding:16px 0;border-bottom:1px solid var(--line);font-size:15px}
.spec dt{color:var(--mute)}
.spec dd{font-weight:700}

/* 機密 */
.conf{background:var(--ink);color:var(--on-ink);border:0!important}
.conf .cols{align-items:center}
.conf h2{display:flex;gap:18px;align-items:flex-start;font-size:clamp(24px,2.9vw,38px);text-wrap:nowrap}
.conf svg{flex:none;width:.9em;height:.9em;margin-top:.28em;stroke:var(--signal)}
.conf p{color:#D5DAD6}
.conf p+p{margin-top:12px}
.conf .link{margin-top:24px}

/* 流れ */
.steps{list-style:none;display:grid;grid-template-columns:repeat(3,1fr);margin-top:clamp(40px,5vw,72px);position:relative}
.steps::before,.steps::after{content:"";position:absolute;left:0;right:0;top:0;height:1px;background:var(--line)}
.steps::after{background:var(--signal);transform:scaleX(0);transform-origin:0 50%;transition:transform 1.6s cubic-bezier(.2,.7,.2,1)}
.steps.in::after{transform:none}
.steps li{padding:28px clamp(16px,2.4vw,36px) 0 0;position:relative}
.steps li::before{content:"";position:absolute;left:0;top:-4px;width:2px;height:9px;background:var(--signal)}
.steps b{display:block;font:800 clamp(34px,4vw,56px)/1 var(--serif);color:var(--steel-2);font-feature-settings:"lnum";margin-bottom:18px;-webkit-text-stroke:1px var(--steel-1);color:transparent}
.steps h3{margin-bottom:10px}
.steps p{color:var(--mute);font-size:15px}

.budget{margin-top:clamp(40px,5vw,72px);padding:clamp(24px,3.4vw,44px);background:var(--paper-2);border-left:3px solid var(--signal)}
.budget p{margin:12px 0 20px;color:var(--mute);max-width:44em}

/* FAQ */
.faq details{border-bottom:1px solid var(--line)}
.faq details:first-child{border-top:1px solid var(--line)}
.faq summary{list-style:none;cursor:pointer;display:flex;justify-content:space-between;align-items:center;gap:20px;padding:24px 0;font-weight:700;font-size:clamp(15px,1.4vw,18px);line-height:1.6}
.faq summary::-webkit-details-marker{display:none}
.faq summary i{flex:none;width:14px;height:14px;position:relative}
.faq summary i::before,.faq summary i::after{content:"";position:absolute;left:0;top:50%;width:100%;height:1px;background:currentColor;transition:transform .35s cubic-bezier(.2,.7,.2,1)}
.faq summary i::after{transform:rotate(90deg)}
.faq details[open] summary i::after{transform:rotate(0)}
.faq summary:hover{color:var(--signal)}
.faq .a{padding:0 34px 26px 0;color:var(--mute);animation:fadeIn .4s ease}

/* 最後の相談 */
.last{background:var(--ink);color:var(--on-ink);padding-block:clamp(80px,11vw,170px);position:relative;overflow:hidden}
.last canvas{position:absolute;inset:0;width:100%;height:100%;opacity:.26}
.last .wrap{position:relative;display:grid;grid-template-columns:minmax(0,1fr) auto;gap:clamp(28px,5vw,64px);align-items:end}
.last h2{font-size:clamp(30px,5.4vw,76px);font-weight:800;line-height:1.3}
.last small{display:block;margin-top:12px;font-size:12px;color:var(--on-ink-mute)}

/* フッター */
footer{padding-block:clamp(40px,5vw,64px) calc(32px + env(safe-area-inset-bottom,0px));font-size:14px}
.foot{display:flex;justify-content:space-between;gap:32px;flex-wrap:wrap}
.foot .logo{color:var(--ink);font-size:30px;margin-bottom:14px}
.foot p{color:var(--mute);line-height:1.9}
.foot nav{display:grid;grid-template-columns:repeat(2,auto);gap:10px 40px;align-content:start;font-weight:500}
.foot nav a:hover,.foot-b a:hover{color:var(--signal)}
.foot-b{display:flex;gap:10px 28px;flex-wrap:wrap;margin-top:40px;padding-top:20px;border-top:1px solid var(--line);font-size:12px;color:var(--mute)}

@media(max-width:860px){
  :root{--head-h:60px}
  .nav a:not(.btn){display:none}
  .logo span{display:none}
  .hero-photo{inset:0;-webkit-mask-image:linear-gradient(180deg,#000 0,transparent 58%);mask-image:linear-gradient(180deg,#000 0,transparent 58%);opacity:.8}
  .hero{min-height:100svh}
  .hero-sub{grid-template-columns:1fr}
  .hero-cta .btn{width:100%;justify-content:space-between}
  
  .facts{grid-template-columns:auto auto 1fr}
  .facts div{padding-right:14px}
  .facts div+div{padding-left:14px}
  .facts dt{height:auto;min-height:3.4em;font-size:17px;line-height:1.3;white-space:normal;align-content:flex-end}
  .facts dt b{font-size:2em;flex-basis:100%}
  .facts dd{font-size:11px;line-height:1.6}
  .cols,.svc{grid-template-columns:1fr}
  .grit-top{flex-direction:column;align-items:flex-start;gap:10px}
  .grit-top p{font-size:13px}
  .plate{height:clamp(180px,36svh,320px)}
  .scale li{font-size:0}
  .scale li b{font-size:10px;letter-spacing:0;white-space:nowrap}
  .bore,.works,.steps{grid-template-columns:1fr}
  .works li{padding:18px 0}
  .works li+li{padding-left:0;border-left:0;border-top:1px solid var(--line)}
  .steps::before,.steps::after{right:auto;bottom:0;width:1px;height:auto}
  .steps::after{transform:scaleY(0);transform-origin:50% 0}
  .steps li{padding:0 0 36px 28px}
  .steps li::before{left:-4px;top:.5em;width:9px;height:2px}
  .steps b{margin-bottom:10px}
  .last .wrap{grid-template-columns:1fr}
  .last .btn{width:100%;justify-content:space-between}
  .spec div{grid-template-columns:1fr;gap:2px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,::before,::after{animation-duration:.01ms!important;animation-delay:0s!important;transition-duration:.01ms!important}
  .grit{height:auto}
  .grit-pin{position:static;height:auto;padding-block:calc(var(--head-h) + 32px) 72px}
}