@charset "UTF-8";

/* =========================================================
   HPC-GENIE  —  refined academic / R&D theme
   Navy base, restrained brass accent, hairline structure.
   HTML + CSS only.
   ========================================================= */

:root{
  --navy:#0f2544;        /* masthead / primary dark   */
  --navy-2:#15325a;      /* gradient partner          */
  --ink:#14263f;         /* headings                  */
  --text:#293544;        /* body text                 */
  --muted:#6b7688;       /* secondary text            */
  --paper:#f5f6f7;       /* page background           */
  --panel:#ffffff;       /* card background           */
  --line:#e4e7ec;        /* hairline border           */
  --line-2:#d5dbe3;      /* slightly stronger rule    */
  --link:#1a539e;        /* steel-blue links          */
  --link-hover:#103b76;
  --brass:#a9843f;       /* distinguished accent      */
  --brass-2:#c2a05c;
  --steel:#345a86;       /* secondary cool accent     */
  --serif:"Noto Serif JP","Hiragino Mincho ProN","Yu Mincho","Times New Roman",serif;
  --sans:"Noto Sans JP","Hiragino Kaku Gothic ProN","Yu Gothic","Meiryo",system-ui,-apple-system,"Segoe UI",sans-serif;
}

*{ box-sizing:border-box; }
html{ scroll-behavior:smooth; }

body{
  margin:0;
  font-family:var(--sans);
  color:var(--text);
  line-height:1.85;
  background:var(--paper);
  border-top:3px solid var(--navy);
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}

/* ---------- Masthead ---------- */
header{
  position:relative;
  text-align:center;
  padding:3rem 1.3rem 2.5rem;
  color:#fff;
  background:linear-gradient(180deg,var(--navy-2) 0%,var(--navy) 100%);
  border-bottom:3px solid var(--brass);
}
header h1{
  font-family:var(--serif);
  position:relative;
  margin:0 auto .9rem;
  max-width:940px;
  font-size:clamp(1.9rem,3.8vw,2.7rem);
  font-weight:700;
  line-height:1.45;
  letter-spacing:.02em;
}
header h1 .subtitle{
  display:block;
  font-size:.68em;
  font-weight:600;
  line-height:1.4;
  letter-spacing:.01em;
  margin-top:.35em;
}
header > div{
  font-size:1.2rem;
  color:#c6d2e2;
  line-height:1.7;
  max-width:660px;
  margin:.2rem auto 0;
  padding-top:.9rem;
  border-top:1px solid rgba(255,255,255,.16);
}
header a{ color:#d7e3f5; text-decoration:none; }
header a:hover{ color:#fff; text-decoration:underline; }

/* ---------- Navigation (centered, below title) ---------- */
.topnav{
  position:sticky; top:0; z-index:100;
  display:flex; justify-content:center; flex-wrap:wrap;
  padding:.35rem 1rem;
  background:var(--navy);
  border-bottom:1px solid rgba(255,255,255,.08);
  box-shadow:0 1px 6px rgba(8,20,40,.20);
}
.navlinks{ display:flex; flex-wrap:wrap; justify-content:center; gap:.1rem; }
.navlinks a{
  position:relative;
  color:#cdd7e6; text-decoration:none;
  font-size:1.2rem; font-weight:500; letter-spacing:.03em;
  padding:.5em 1.1em;
}
.navlinks a::after{
  content:""; position:absolute; left:.95em; right:.95em; bottom:.28em;
  height:2px; background:var(--brass-2);
  transform:scaleX(0); transform-origin:center;
  transition:transform .18s ease;
}
.navlinks a:hover{ color:#fff; text-decoration:none; }
.navlinks a:hover::after,
.navlinks a.active::after{ transform:scaleX(1); }
.navlinks a.active{ color:#fff; }

/* ---------- Layout ---------- */
main{
  max-width:1000px;
  margin:2.2rem auto 4rem;
  padding:0 1.15rem;
}
main > div,
main > section{
  background:var(--panel);
  border:1px solid var(--line);
  border-radius:6px;
  padding:1.7rem 1.9rem;
  margin-bottom:1.25rem;
  box-shadow:0 1px 2px rgba(16,36,64,.04);
}

/* ---------- Headings ---------- */
section h2{
  font-family:var(--serif);
  position:relative;
  margin:.1rem 0 1.15rem;
  padding-bottom:.55rem;
  font-size:clamp(1.18rem,2.1vw,1.4rem);
  font-weight:700;
  color:var(--ink);
  letter-spacing:.01em;
  border-bottom:1px solid var(--line);
  scroll-margin-top:66px;
}
section h2::after{
  content:""; position:absolute; left:0; bottom:-1px;
  width:54px; height:2px; background:var(--brass);
}
section h3{
  margin:1.7em 0 .6em;
  padding-left:.65em;
  font-size:1.02rem; font-weight:700;
  color:var(--steel);
  letter-spacing:.02em;
  border-left:3px solid var(--brass);
  line-height:1.4;
}

/* ---------- Text & links ---------- */
p{ margin:.55em 0 .9em; }
a{ color:var(--link); text-decoration:none; transition:color .15s ease; }
a:hover{ color:var(--link-hover); text-decoration:underline; }
strong{ font-weight:700; color:var(--ink); }

/* ---------- Lists ---------- */
ul{ margin:.4rem 0 .6rem; padding-left:1.35em; }
li{ margin:.4em 0; }
li::marker{ color:var(--steel); }

dl{ margin:1rem 0 .2rem; }
dt{ font-family:var(--serif); font-weight:700; color:var(--ink); margin-top:.7rem; }
dd{ margin:.1rem 0 .5rem 1.1rem; }

/* ---------- Images ---------- */
img{
  display:block; max-width:100%; height:auto;
  margin:1rem auto .3rem;
  border:1px solid var(--line);
  border-radius:4px;
  box-shadow:0 2px 10px rgba(16,36,64,.10);
}

/* ---------- Hero (text left, image right) ---------- */
.hero::after{ content:""; display:block; clear:both; }
.hero-img{
  float:right;
  width:400px; max-width:48%;
  margin:.2rem 0 1rem 1.7rem;
  text-align:center;
}
.hero-img img{ width:100%; margin:0 0 .4rem; }
.hero-img figcaption{ font-size:.76rem; color:var(--muted); letter-spacing:.02em; }

/* ---------- Preformatted diagram ---------- */
pre{
  background:#fafbfc;
  border:1px solid var(--line);
  border-left:3px solid var(--steel);
  border-radius:4px;
  padding:1.1em 1.2em;
  color:#22344c;
  font-family:"SFMono-Regular",Consolas,"Liberation Mono",Menlo,monospace;
  font-size:.9rem; line-height:1.55;
  overflow-x:auto;
}

/* ---------- Badges (restrained) ---------- */
.award{
  color:#cc0000;
}
.invited{
  color:#cc0000;
}

/* email */
#email{
  font-family:Consolas,Menlo,monospace;
  background:#eef2f7; color:var(--navy);
  padding:.08em .45em; border-radius:4px;
}

/* ---------- Button ---------- */
.btn{
  display:inline-block; margin-top:.25rem;
  background:var(--navy); color:#fff !important;
  text-decoration:none; font-weight:600; letter-spacing:.03em;
  padding:.62em 1.35em;
  border:1px solid var(--navy); border-radius:5px;
  transition:background .15s ease, border-color .15s ease;
}
.btn:hover{ background:var(--steel); border-color:var(--steel); text-decoration:none; color:#fff; }

/* ---------- Responsive ---------- */
@media (max-width:640px){
  header{ padding:2.2rem 1rem 1.9rem; }
  main{ margin:1.5rem auto 2.6rem; }
  main > div,
  main > section{ padding:1.25rem 1.2rem; }
  .navlinks a{ padding:.45em .7em; font-size:1.02rem; }
  .hero-img{ float:none; width:230px; max-width:72%; margin:0 auto 1rem; }
}