/* 株式会社さつきAI コーポレートサイト v2 (2026-09) */
:root{
  --ink:#333333;
  --ink-light:#666666;
  --line:#e5e7e6;
  --bg:#ffffff;
  --bg-gray:#f4f5f4;
  --bg-gray-2:#e9ebea;
  --sage:#758785;
  --sage-dark:#4a5856;
  --sage-light:#e8ecea;
  --ghost:#eef0ef;
  --indigo:#1E1B4B;
  --font-sans:"Yu Gothic Medium","游ゴシック Medium","Yu Gothic","游ゴシック","Hiragino Sans","Noto Sans JP",sans-serif;
  --font-en:"Helvetica Neue",Arial,"Noto Sans JP",sans-serif;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:var(--font-sans);color:var(--ink);background:var(--bg);line-height:1.9;font-size:15px;letter-spacing:.03em;-webkit-font-smoothing:antialiased}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
ul{list-style:none}
.wrap{width:min(1120px,92%);margin:0 auto}
.en{font-family:var(--font-en);letter-spacing:.12em;text-transform:uppercase}

/* header */
.header{position:fixed;top:0;left:0;right:0;z-index:50;background:rgba(255,255,255,.92);backdrop-filter:blur(8px);border-bottom:1px solid transparent;transition:border-color .3s}
.header.scrolled{border-bottom-color:var(--line)}
.header .wrap{display:flex;align-items:center;justify-content:space-between;height:72px}
.logo{display:flex;align-items:baseline;gap:10px;font-weight:700;font-size:18px;letter-spacing:.06em}
.logo small{font-family:var(--font-en);font-weight:400;font-size:10px;letter-spacing:.2em;color:var(--sage-dark)}
.nav ul{display:flex;gap:30px}
.nav a{display:flex;flex-direction:column;align-items:center;line-height:1.3;font-size:13px;font-weight:600;padding:6px 0;position:relative}
.nav a small{font-family:var(--font-en);font-size:9px;letter-spacing:.18em;color:var(--sage);font-weight:400;margin-top:2px}
.nav a::after{content:"";position:absolute;left:0;right:0;bottom:-2px;height:1px;background:var(--ink);transform:scaleX(0);transition:transform .3s;transform-origin:left}
.nav a:hover::after,.nav a.current::after{transform:scaleX(1)}
.menu-btn{display:none;width:40px;height:40px;background:none;border:0;cursor:pointer;position:relative}
.menu-btn span{position:absolute;left:8px;right:8px;height:1.5px;background:var(--ink);transition:.3s}
.menu-btn span:nth-child(1){top:13px}.menu-btn span:nth-child(2){top:20px}.menu-btn span:nth-child(3){top:27px}
.menu-open .menu-btn span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.menu-open .menu-btn span:nth-child(2){opacity:0}
.menu-open .menu-btn span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

/* hero */
.hero{position:relative;min-height:100vh;display:flex;align-items:center;color:#fff;overflow:hidden;background:#1c2423}
.hero-bg{position:absolute;inset:0;background:
  radial-gradient(60% 80% at 80% 20%,rgba(117,135,133,.55),transparent 60%),
  radial-gradient(50% 60% at 15% 90%,rgba(74,88,86,.6),transparent 60%),
  linear-gradient(160deg,#0f1514 0%,#1c2423 45%,#2b3634 100%)}
.hero-bg img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;opacity:.55}
.hero-grid{position:absolute;inset:0;background-image:linear-gradient(rgba(255,255,255,.05) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.05) 1px,transparent 1px);background-size:80px 80px;mask-image:linear-gradient(180deg,rgba(0,0,0,.7),transparent 90%)}
.hero .wrap{position:relative;padding:140px 0 100px}
.hero .eyebrow{font-family:var(--font-en);font-size:11px;letter-spacing:.3em;color:rgba(255,255,255,.7);margin-bottom:28px}
.hero h1{font-size:clamp(30px,4.6vw,56px);font-weight:600;line-height:1.5;letter-spacing:.04em;margin-bottom:28px}
.hero p{font-size:clamp(14px,1.3vw,17px);line-height:2.1;color:rgba(255,255,255,.85);max-width:640px}
.hero .actions{display:flex;gap:16px;flex-wrap:wrap;margin-top:44px}
.hero .scroll{position:absolute;left:50%;bottom:28px;transform:translateX(-50%);font-family:var(--font-en);font-size:10px;letter-spacing:.3em;color:rgba(255,255,255,.6)}
.hero .scroll::after{content:"";display:block;width:1px;height:40px;background:rgba(255,255,255,.5);margin:10px auto 0;animation:scrollline 2s infinite}
@keyframes scrollline{0%{transform:scaleY(0);transform-origin:top}50%{transform:scaleY(1);transform-origin:top}51%{transform-origin:bottom}100%{transform:scaleY(0);transform-origin:bottom}}

/* page hero (sub pages) */
.page-hero{padding:150px 0 70px;background:var(--bg-gray);position:relative;overflow:hidden}
.page-hero .ghost{position:absolute;right:-2%;top:40px;font-family:var(--font-en);font-size:clamp(70px,14vw,180px);font-weight:700;color:#fff;letter-spacing:.02em;line-height:1;pointer-events:none;white-space:nowrap}
.page-hero .wrap{position:relative}
.page-hero .tag{display:inline-block;font-size:12px;letter-spacing:.1em;border:1px solid var(--ink);padding:3px 12px;margin-bottom:22px}
.page-hero h1{font-size:clamp(30px,4vw,46px);font-weight:600;line-height:1.4;letter-spacing:.04em}
.page-hero h1 small{display:block;font-family:var(--font-en);font-size:12px;letter-spacing:.3em;color:var(--sage-dark);margin-bottom:12px;font-weight:400}
.page-hero .lead{font-size:clamp(17px,2vw,22px);font-weight:600;margin-top:26px;line-height:1.7}
.page-hero .sub{margin-top:18px;max-width:760px;color:var(--ink-light)}

/* buttons */
.btn{display:inline-flex;align-items:center;gap:14px;font-size:13px;font-weight:600;letter-spacing:.12em;padding:14px 32px;border:1px solid currentColor;transition:.3s;position:relative;overflow:hidden}
.btn::after{content:"→";transition:transform .3s}
.btn:hover::after{transform:translateX(4px)}
.btn.light{color:#fff}
.btn.light:hover{background:#fff;color:var(--ink)}
.btn.dark{color:var(--ink)}
.btn.dark:hover{background:var(--ink);color:#fff}
.btn.solid{background:var(--ink);color:#fff;border-color:var(--ink)}
.btn.solid:hover{background:var(--sage-dark);border-color:var(--sage-dark)}

/* section */
.section{padding:110px 0;position:relative}
.section.gray{background:var(--bg-gray)}
.sec-head{margin-bottom:56px;position:relative}
.sec-head .ghost{font-family:var(--font-en);font-size:clamp(48px,9vw,112px);font-weight:700;letter-spacing:.02em;color:var(--ghost);line-height:1;position:absolute;left:-4px;top:-38px;pointer-events:none;white-space:nowrap}
.section.gray .sec-head .ghost{color:#fff}
.sec-head h2{position:relative;font-size:clamp(24px,3vw,34px);font-weight:600;letter-spacing:.06em;line-height:1.5}
.sec-head h2::before{content:"";display:block;width:36px;height:2px;background:var(--sage-dark);margin-bottom:18px}
.sec-head p{position:relative;margin-top:18px;color:var(--ink-light);max-width:720px}

/* about split with offset image */
.split{display:grid;grid-template-columns:1fr 1fr;gap:70px;align-items:center}
.split .text h3{font-size:clamp(20px,2.3vw,28px);font-weight:600;line-height:1.6;margin-bottom:22px}
.split .text p{margin-bottom:16px;color:var(--ink)}
.split .text .btn{margin-top:14px}
.offset{position:relative;padding:40px 0 0 40px}
.offset::before{content:"";position:absolute;left:0;top:0;width:78%;height:78%;background:var(--bg-gray-2);z-index:0}
.offset img,.offset .frame{position:relative;z-index:1;box-shadow:0 20px 50px rgba(0,0,0,.12)}
.offset.left{padding:40px 40px 0 0}
.offset.left::before{left:auto;right:0}
.frame{background:#fff;border:1px solid var(--line);aspect-ratio:16/10;display:flex;align-items:center;justify-content:center;color:var(--ink-light);font-size:13px;letter-spacing:.1em;text-align:center;line-height:2}
.frame.dark{background:#1c2423;color:rgba(255,255,255,.75)}

/* product cards */
.products{display:grid;grid-template-columns:repeat(2,1fr);gap:40px 48px}
.pcard{display:block;background:#fff;border:1px solid var(--line);transition:.35s;position:relative}
.section.gray .pcard{border-color:transparent}
.pcard:hover{transform:translateY(-4px);box-shadow:0 20px 50px rgba(0,0,0,.08)}
.pcard .thumb{aspect-ratio:16/9;background:var(--bg-gray-2);overflow:hidden;position:relative}
.pcard .thumb img{width:100%;height:100%;object-fit:cover;object-position:top;transition:transform .6s}
.pcard:hover .thumb img{transform:scale(1.03)}
.pcard .thumb .soon{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;flex-direction:column;gap:6px;color:var(--ink-light);font-size:12px;letter-spacing:.15em;background:linear-gradient(135deg,#eef0ef,#e2e5e4)}
.pcard .thumb .soon b{font-family:var(--font-en);font-size:28px;letter-spacing:.06em;color:var(--sage-dark)}
.pcard .body{padding:28px 30px 32px}
.pcard .cat{font-size:11px;letter-spacing:.12em;color:var(--sage-dark);margin-bottom:8px}
.pcard h3{font-size:22px;font-weight:700;letter-spacing:.06em;line-height:1.3}
.pcard h3 small{font-family:var(--font-en);font-size:11px;letter-spacing:.24em;color:var(--ink-light);font-weight:400;margin-left:12px}
.pcard .copy{font-weight:600;margin:12px 0 8px;line-height:1.7}
.pcard p{font-size:14px;color:var(--ink-light)}
.pcard .more{display:inline-block;margin-top:18px;font-family:var(--font-en);font-size:11px;letter-spacing:.2em;border-bottom:1px solid var(--ink);padding-bottom:2px}
.pcard .more::after{content:" →"}
.pcard.base{background:#1c2423;color:#fff;border-color:#1c2423}
.pcard.base .thumb{background:#1c2423}
.base-thumb{height:100%;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:12px;background:radial-gradient(60% 80% at 70% 30%,rgba(117,135,133,.45),transparent 60%),#1c2423}
.base-thumb img{width:120px;height:120px;object-fit:contain}
.base-thumb span{font-family:var(--font-en);font-size:10px;letter-spacing:.3em;color:#9fb3af}
.pcard.base .cat{color:#9fb3af}
.pcard.base h3 small{color:rgba(255,255,255,.6)}
.pcard.base p{color:rgba(255,255,255,.8)}
.pcard.base .more{border-bottom-color:#fff}

/* foundation (MURAKUMO) */
.foundation{background:#1c2423;color:#fff}
.foundation .sec-head .ghost{color:rgba(255,255,255,.06)}
.foundation .sec-head h2::before{background:#9fb3af}
.foundation .sec-head p{color:rgba(255,255,255,.75)}
.flow{display:grid;grid-template-columns:repeat(5,1fr);gap:0;margin:40px 0 30px;border:1px solid rgba(255,255,255,.18)}
.flow div{padding:22px 16px;border-right:1px solid rgba(255,255,255,.18);font-size:13px;line-height:1.8;position:relative}
.flow div:last-child{border-right:0}
.flow div b{display:block;font-size:14px;margin-bottom:6px;letter-spacing:.06em}
.flow div small{display:block;font-family:var(--font-en);font-size:9px;letter-spacing:.2em;color:#9fb3af;margin-bottom:8px}
.flow div::after{content:"›";position:absolute;right:-7px;top:50%;transform:translateY(-50%);background:#1c2423;color:#9fb3af;padding:0 3px;font-size:20px;z-index:1}
.flow div:last-child::after{display:none}
.foundation .notes{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;margin-top:40px}
#murakumo .notes{grid-template-columns:repeat(4,1fr)}
.foundation .notes div{border-top:1px solid rgba(255,255,255,.25);padding-top:16px;font-size:13px;color:rgba(255,255,255,.8)}
.foundation .notes b{display:block;color:#fff;font-size:15px;margin-bottom:6px}

/* feature list */
.features{display:grid;grid-template-columns:repeat(4,1fr);gap:36px}
.features div{border-top:1px solid var(--ink);padding-top:22px}
.features .num{font-family:var(--font-en);font-size:12px;letter-spacing:.2em;color:var(--sage-dark);margin-bottom:12px}
.features h3{font-size:17px;font-weight:700;line-height:1.6;margin-bottom:10px}
.features p{font-size:14px;color:var(--ink-light)}

/* generic 3 col */
.cols3{display:grid;grid-template-columns:repeat(3,1fr);gap:32px}
.cols2{display:grid;grid-template-columns:repeat(2,1fr);gap:32px}
.box{background:#fff;border:1px solid var(--line);padding:32px 30px}
.section.gray .box{border-color:transparent}
.box .num{font-family:var(--font-en);font-size:12px;letter-spacing:.2em;color:var(--sage-dark);margin-bottom:10px}
.box h3{font-size:18px;font-weight:700;line-height:1.6;margin-bottom:12px}
.box p{font-size:14px;color:var(--ink-light)}
.box p+p{margin-top:8px}

/* compare table */
.tbl{width:100%;border-collapse:collapse;font-size:14px;background:#fff}
.tbl th,.tbl td{border:1px solid var(--line);padding:16px 18px;text-align:left;vertical-align:top;line-height:1.8}
.tbl th{background:var(--bg-gray);font-weight:700;white-space:nowrap}
.tbl thead th{background:var(--sage-dark);color:#fff;border-color:var(--sage-dark)}
.tbl thead th:first-child{background:var(--ink);border-color:var(--ink)}
.tbl td.now{color:var(--ink-light)}
.tbl td.after{font-weight:600}
.tbl-wrap{overflow-x:auto}

/* screens gallery */
.gallery{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.gallery figure{background:#fff;border:1px solid var(--line)}
.gallery img{aspect-ratio:16/9;object-fit:cover;object-position:top}
.gallery figcaption{padding:12px 16px;font-size:13px;color:var(--ink-light);border-top:1px solid var(--line)}

/* philosophy */
.philosophy{text-align:center;background:var(--sage-light)}
.philosophy .en-title{font-family:var(--font-en);font-size:11px;letter-spacing:.3em;color:var(--sage-dark);margin-bottom:24px}
.philosophy h2{font-size:clamp(22px,3vw,32px);font-weight:600;letter-spacing:.1em;margin-bottom:30px}
.philosophy p{max-width:640px;margin:0 auto;line-height:2.3}

/* company */
.dl{display:grid;grid-template-columns:180px 1fr;border-top:1px solid var(--line)}
.dl dt,.dl dd{padding:18px 8px;border-bottom:1px solid var(--line);font-size:14px}
.dl dt{font-weight:700;color:var(--sage-dark)}
.message{display:grid;grid-template-columns:260px 1fr;gap:56px;align-items:start;margin-bottom:70px}
.message .photo{position:relative;padding:22px 0 0 22px}
.message .photo::before{content:"";position:absolute;left:0;top:0;width:80%;height:80%;background:var(--bg-gray-2)}
.message .photo img{position:relative;aspect-ratio:1/1;object-fit:cover;object-position:top}
.message .photo .name{position:relative;margin-top:14px;font-size:13px}
.message .photo .name b{display:block;font-size:16px}
.message h3{font-size:clamp(20px,2.2vw,26px);font-weight:600;line-height:1.6;margin-bottom:20px}
.message p{margin-bottom:14px}
.message .sign{text-align:right;font-weight:600;margin-top:20px}

/* contact */
.contact{background:var(--ink);color:#fff}
.contact .sec-head .ghost{color:rgba(255,255,255,.06)}
.contact .sec-head h2::before{background:#9fb3af}
.contact .sec-head p{color:rgba(255,255,255,.75)}
.contact .cols2{gap:40px}
.contact .cbox{border:1px solid rgba(255,255,255,.25);padding:36px 34px}
.contact .cbox .en{font-size:10px;color:#9fb3af;margin-bottom:12px}
.contact .cbox h3{font-size:20px;font-weight:700;margin-bottom:12px}
.contact .cbox p{font-size:14px;color:rgba(255,255,255,.8);margin-bottom:18px}
.contact .cbox .mail{font-family:var(--font-en);font-size:20px;letter-spacing:.04em;text-transform:none;display:block;margin:6px 0 10px}
.contact small{display:block;font-size:12px;color:rgba(255,255,255,.6);margin-top:8px;line-height:1.8}

/* footer */
.footer{background:#111516;color:rgba(255,255,255,.75);padding:60px 0 30px;font-size:13px}
.footer .top{display:flex;justify-content:space-between;flex-wrap:wrap;gap:30px;margin-bottom:40px}
.footer .logo{color:#fff}
.footer .logo small{color:#9fb3af}
.footer address{font-style:normal;margin-top:12px;line-height:1.9}
.footer ul{display:flex;gap:26px;flex-wrap:wrap}
.footer ul a:hover{color:#fff}
.footer .copy{border-top:1px solid rgba(255,255,255,.12);padding-top:22px;font-family:var(--font-en);font-size:10px;letter-spacing:.14em;color:rgba(255,255,255,.45);text-transform:none}

/* CTA band */
.cta-band{background:var(--sage-dark);color:#fff;padding:70px 0;text-align:center}
.cta-band h2{font-size:clamp(20px,2.6vw,28px);font-weight:600;margin-bottom:14px;letter-spacing:.06em}
.cta-band p{color:rgba(255,255,255,.85);margin-bottom:28px}

/* fade in */
.fade{opacity:0;transform:translateY(26px);transition:opacity .9s ease,transform .9s ease}
.fade.in{opacity:1;transform:none}
.fade.d1{transition-delay:.1s}.fade.d2{transition-delay:.2s}.fade.d3{transition-delay:.3s}.fade.d4{transition-delay:.4s}

/* breadcrumb */
.crumb{font-size:12px;color:var(--ink-light);margin-bottom:24px;letter-spacing:.06em}
.crumb a:hover{text-decoration:underline}

.note{font-size:12px;color:var(--ink-light);margin-top:22px;line-height:1.9}

/* responsive */
@media(max-width:960px){
  .split,.products,.cols3,.cols2,.features,.gallery,.foundation .notes,.message{grid-template-columns:1fr}
  .flow{grid-template-columns:1fr}
  .flow div{border-right:0;border-bottom:1px solid rgba(255,255,255,.18)}
  .flow div:last-child{border-bottom:0}
  .flow div::after{content:"⌄";right:auto;left:50%;top:auto;bottom:-13px;transform:translateX(-50%)}
  .split .visual{order:-1}
  .message .photo{max-width:260px}
  .dl{grid-template-columns:1fr}
  .dl dt{border-bottom:0;padding-bottom:0}
}
@media(max-width:820px){
  .nav{position:fixed;inset:72px 0 0 0;background:#fff;transform:translateX(100%);transition:.35s}
  .menu-open .nav{transform:none}
  .nav ul{flex-direction:column;gap:0;padding:20px 8%}
  .nav a{flex-direction:row;justify-content:space-between;padding:18px 0;border-bottom:1px solid var(--line);font-size:16px}
  .nav a::after{display:none}
  .menu-btn{display:block}
  .section{padding:80px 0}
  .hero .wrap{padding:130px 0 90px}
}

/* consulting (3 columns) */
.features.three{grid-template-columns:repeat(3,1fr)}
@media (max-width:960px){.features.three{grid-template-columns:1fr}}

/* v5: tall screenshots (phone) */
.gallery.tall img{aspect-ratio:auto;height:460px;width:100%;object-fit:contain;object-position:top center;background:var(--bg-gray-2)}
.connect{display:grid;grid-template-columns:repeat(3,1fr);gap:0;border-top:1px solid var(--line)}
.connect div{border-bottom:1px solid var(--line);padding:20px 18px 20px 0}
.connect b{display:block;font-size:16px;margin-bottom:4px}
.connect span{font-size:13px;color:var(--ink-light)}
@media (max-width:960px){.connect{grid-template-columns:1fr}}