@charset "UTF-8";
:root{
  --navy:#0d2a55;
  --ink:#18345a;
  --muted:#657d9b;
  --blue:#0867e2;
  --line:#dbe8f7;
  --serif:"Noto Serif JP","Noto Serif CJK JP","Hiragino Mincho ProN","Yu Mincho",serif;
  --sans:"Noto Sans JP","Noto Sans CJK JP","Hiragino Sans","Yu Gothic",system-ui,sans-serif;
}
*{box-sizing:border-box}
html{min-height:100%;background:#f9fcff;scroll-behavior:smooth}
body{margin:0;min-height:100vh;color:var(--ink);font-family:var(--sans);-webkit-font-smoothing:antialiased;position:relative;isolation:isolate;overflow-x:hidden;background:
  radial-gradient(ellipse 52% 31% at 0% 4%,rgba(118,204,255,.24),transparent 84%),
  radial-gradient(ellipse 40% 30% at 94% 97%,rgba(73,164,251,.20),transparent 83%),
  radial-gradient(ellipse 50% 42% at 35% 76%,rgba(198,233,255,.12),transparent 90%),
  #fcfdff;
}
body::before,body::after{content:"";z-index:-1;position:fixed;pointer-events:none;border-radius:50%;filter:blur(40px)}
body::before{width:min(60vw,550px);height:min(58vw,520px);top:-22%;left:-19%;background:rgba(111,202,255,.23)}
body::after{width:min(55vw,560px);height:min(60vw,570px);bottom:-24%;right:-18%;background:rgba(84,171,246,.22)}
a{color:inherit;text-decoration:none}
button{font:inherit}
a:focus-visible,button:focus-visible{outline:3px solid #2f91f1;outline-offset:5px}
[hidden]{display:none!important}

/* Minimal home / exact three navigation choices */
.home{min-height:100vh;min-height:100svh;display:grid;place-items:center;padding:72px 25px 94px}
.home-content{width:min(100%,600px);text-align:center;animation:arrive .66s ease-out both}
.home h1{font-family:var(--serif);font-size:clamp(47px,8vw,72px);font-weight:650;line-height:1.3;letter-spacing:.045em;color:#082958;margin:0 0 19px;text-wrap:balance}
.home-tagline{font-size:clamp(13px,2.7vw,16px);line-height:1.8;letter-spacing:.10em;color:#607694;margin:0 0 58px}
.entry-links{display:grid;gap:17px}
.entry-link{min-height:87px;display:flex;align-items:center;justify-content:space-between;gap:16px;text-align:left;padding:20px 29px;border-radius:18px;border:1px solid rgba(192,212,238,.76);font-size:clamp(15px,2.9vw,18px);font-weight:700;letter-spacing:.012em;line-height:1.55;box-shadow:0 14px 36px rgba(13,61,119,.07),0 3px 10px rgba(19,73,118,.035);transition:transform .22s cubic-bezier(.2,.8,.2,1),box-shadow .22s,border-color .22s,background .22s}
.entry-link svg{width:24px;height:24px;flex:0 0 24px;stroke:currentColor;stroke-width:1.7;fill:none;stroke-linecap:round;stroke-linejoin:round}
.entry-link--primary{color:#fff;border-color:#168de7;background:linear-gradient(105deg,#0870e9 0%,#147de9 56%,#28b0f1 100%);box-shadow:0 14px 32px rgba(11,99,221,.13),0 5px 14px rgba(40,168,241,.09)}
.entry-link--secondary{color:#14325b;background:rgba(255,255,255,.91)}
.entry-link--secondary svg{color:#0b76e8}
.entry-link:hover{transform:translateY(-3px);box-shadow:0 16px 35px rgba(7,83,162,.13);border-color:#76b6f2}
.entry-link:active{transform:translateY(1px) scale(.997)}
.home-about{display:inline-flex;align-items:center;gap:15px;margin:44px auto 0;padding:9px 12px;font-size:14px;color:#637c9a;letter-spacing:.035em;text-decoration:underline;text-underline-offset:8px;text-decoration-color:#a0b5cc;transition:color .18s}
.home-about:hover{color:#096bcf}
.home-about span{font-size:20px;text-decoration:none}

/* About page */
.about{width:min(100% - 42px,800px);margin:0 auto;padding:72px 0 85px;display:flex;align-items:center;flex-direction:column}
.about-hero{text-align:center;max-width:730px}
.cloud-logo{width:116px;height:82px;display:block;margin:0 auto 18px;filter:drop-shadow(0 7px 13px rgba(48,146,242,.08))}
.about h1{font-family:var(--serif);color:#0c2b5b;font-weight:650;letter-spacing:.035em;font-size:clamp(34px,6.7vw,49px);line-height:1.38;margin:0 0 20px;text-wrap:balance}
.about-intro{font-size:clamp(14px,2.9vw,17px);line-height:1.95;letter-spacing:.015em;color:#506988;margin:0}
.about-cards{margin:44px 0 0;width:100%;display:grid;gap:16px}
.info-card{display:flex;align-items:flex-start;gap:21px;padding:25px 26px;border:1px solid #d6e6f8;border-radius:21px;background:rgba(255,255,255,.92);box-shadow:0 12px 29px rgba(17,71,129,.037)}
.icon-tile{background:linear-gradient(145deg,#e8f6ff,#eff7ff);border-radius:50%;width:56px;height:56px;flex-shrink:0;display:grid;place-items:center}
.icon-tile svg{width:29px;height:29px;fill:none;stroke:#267fee;stroke-width:1.75;stroke-linecap:round;stroke-linejoin:round}
.info-card h2{font-size:clamp(16px,3.2vw,19px);line-height:1.55;color:#0e2e5f;font-weight:760;letter-spacing:-.015em;margin:2px 0 9px}
.info-card p{font-size:clamp(13px,2.7vw,15px);color:#536b8a;line-height:1.9;letter-spacing:.007em;margin:0}
.about-footnote{color:#8498ad;font-size:11px;line-height:1.75;margin:32px 2px 0;max-width:720px}
.return-link{font-size:15px;margin:38px auto 10px;color:#527396;text-decoration:underline;text-underline-offset:7px;text-decoration-color:#adc4e0;padding:8px 14px;display:flex;align-items:center;gap:12px}
.return-link:hover{color:#0c68d6}
.return-link span{font-size:20px;text-decoration:none}

/* One simple topic listing for each audience */
.page-shell{width:min(calc(100% - 44px),750px);margin:0 auto}
.top-bar{padding:31px 0 0}
.top-home{font-size:14px;font-weight:640;color:#4e79a6;display:inline-flex;align-items:center;gap:10px;padding:7px 0}
.top-home span{font-size:19px}
.top-home:hover{color:#0c76e7}
.list-main{padding:100px 0 86px;min-height:70vh}
.section-kicker{margin:0 0 15px;font-size:13px;font-weight:680;letter-spacing:.03em;color:#237ce0}
.list-main h1{font-family:var(--serif);color:#102d57;font-size:clamp(30px,6.3vw,43px);font-weight:660;line-height:1.45;letter-spacing:.015em;margin:0 0 10px}
.list-subtitle{font-size:14px;color:#69819b;line-height:1.8;margin:0 0 60px}
.list-section-title{font-size:13px;color:#8092a6;font-weight:640;letter-spacing:.08em;margin:0 0 13px}
.lesson-links{border-top:1px solid #dbe6f3}
.lesson-link{padding:24px 2px;display:flex;align-items:center;justify-content:space-between;gap:15px;border-bottom:1px solid #dbe6f3;transition:background .2s ease,transform .2s ease}
.lesson-link:hover{background:rgba(225,241,255,.28);transform:translateX(3px)}
.lesson-title{font-size:clamp(16px,3.8vw,19px);line-height:1.5;color:#18355a;margin:0;font-weight:750;letter-spacing:-.025em}
.lesson-desc{font-size:12px;line-height:1.75;color:#8090a5;margin:6px 0 0}
.lesson-arrow{color:#177cde;font-size:22px;flex-shrink:0}
.list-bottom-hint{font-size:12px;color:#91a0b2;margin:37px 0 0}
.empty-message{font-size:14px;color:#6b8199;padding:22px 0}
.list-footer{border-top:1px solid #e4ebf5;color:#8aa0b5;padding:26px 0 50px;font-size:12px}
.list-footer a:hover{color:#0b69d9}
@keyframes arrive{from{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}
@media(max-width:600px){
 .home{padding:42px 21px 82px}
 .home h1{font-size:clamp(41px,12vw,55px);margin-bottom:18px;letter-spacing:.032em}
 .home-tagline{font-size:13px;letter-spacing:.045em;margin-bottom:54px}
 .entry-links{gap:14px}
 .entry-link{min-height:76px;padding:19px 20px;font-size:15px;border-radius:15px}
 .home-about{margin-top:39px;font-size:13px}
 .about{width:min(calc(100% - 32px),800px);padding:51px 0 62px}
 .cloud-logo{width:103px;height:78px;margin-bottom:13px}
 .about h1{font-size:clamp(32px,8vw,42px);margin-bottom:15px}
 .about-intro{font-size:13px;line-height:1.9}
 .about-cards{margin-top:34px;gap:13px}
 .info-card{padding:20px 18px;border-radius:17px;gap:15px}
 .icon-tile{width:48px;height:48px}
 .icon-tile svg{width:25px;height:25px}
 .info-card h2{font-size:16px;margin:0 0 7px}
 .info-card p{font-size:13.2px;line-height:1.85}
 .desktop-break{display:none}
 .about-footnote{font-size:10px;margin-top:27px}
 .return-link{margin-top:27px;font-size:13px}
 .top-bar{padding-top:20px}
 .list-main{padding:76px 0 86px;min-height:72vh}
 .list-subtitle{margin-bottom:43px}
 .lesson-link{padding:23px 1px}
}
@media(max-width:370px){
 .entry-link{font-size:13px;padding:16px 14px}
 .entry-link svg{width:21px;height:21px}
 .info-card{padding:17px 13px;gap:12px}
 .about-intro{font-size:12px}
}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation-duration:.01ms!important;transition-duration:.01ms!important;scroll-behavior:auto!important}}

/* The minimalist topic selection screen — share the same light blue atmosphere as home. */
.quiet-list .page-shell{
  min-height:100vh;min-height:100svh;
  display:flex;flex-direction:column;
  width:min(calc(100% - 42px),680px);
}
.quiet-list .top-bar{padding-top:27px;flex-shrink:0}
.quiet-list .top-home{font-size:14px;color:#56738f;font-weight:570;letter-spacing:.04em}
.quiet-list .list-main{min-height:0;flex:1;display:flex;align-items:center;justify-content:center;padding:55px 0 125px}
.quiet-lesson-wrap{width:100%;animation:arrive .62s ease-out both}
.quiet-list .lesson-links{border:0;display:grid;gap:17px;width:100%}
.quiet-lesson-card{
  padding:30px 31px;
  border:1px solid rgba(190,214,242,.78);
  background:rgba(255,255,255,.92);
  border-radius:22px;
  box-shadow:0 16px 45px rgba(11,70,137,.075),0 3px 11px rgba(14,87,171,.028);
  text-align:left;gap:18px;
  min-height:197px;
  align-items:center;
  overflow:hidden;
}
.quiet-lesson-card:hover{background:#fff;transform:translateY(-3px);border-color:#91bef5;box-shadow:0 20px 48px rgba(11,70,137,.12)}
.quiet-lesson-card:active{transform:translateY(0px) scale(.995)}
.quiet-lesson-card .lesson-copy{min-width:0;flex:1}
.quiet-lesson-card .lesson-number{display:block;font-size:12px;color:#1374dd;font-weight:750;letter-spacing:.08em;margin-bottom:14px}
.quiet-lesson-card .lesson-title{
  font-family:var(--serif);font-size:clamp(21px,4.2vw,27px);
  font-weight:700;letter-spacing:.005em;line-height:1.55;
  color:#102b56;text-wrap:pretty;white-space:pre-line;
}
.quiet-lesson-card .lesson-desc{font-size:clamp(13px,2.7vw,14px);color:#637b99;line-height:1.85;margin-top:10px;letter-spacing:.015em}
.quiet-lesson-card .lesson-arrow{
  display:grid;place-items:center;border-radius:50%;width:38px;height:38px;
  background:linear-gradient(130deg,#e7f5ff,#f3f8ff);
  color:#0877e6;font-size:26px;line-height:1;flex:0 0 38px;
  transition:transform .2s;
}
.quiet-lesson-card:hover .lesson-arrow{transform:translateX(3px)}
.quiet-list .empty-message{margin:0;text-align:center}
@media(max-width:600px){
  .quiet-list .top-bar{padding-top:20px}
  .quiet-list .list-main{padding:50px 0 104px}
  .quiet-lesson-card{padding:24px 21px;gap:9px;min-height:170px;border-radius:19px}
  .quiet-lesson-card .lesson-number{margin-bottom:12px;font-size:11px}
  .quiet-lesson-card .lesson-title{font-size:clamp(21px,5.4vw,25px);line-height:1.53}
  .quiet-lesson-card .lesson-desc{font-size:13px;margin-top:11px}
  .quiet-lesson-card .lesson-arrow{width:29px;height:29px;flex-basis:29px;font-size:24px;background:transparent}
}
@media(max-width:350px){
 .quiet-list .page-shell{width:min(calc(100% - 30px),680px)}
 .quiet-lesson-card{padding:22px 16px}
 .quiet-lesson-card .lesson-title{font-size:20px}
 .quiet-lesson-card .lesson-desc{font-size:12px}
}