@charset "UTF-8";
/* CSS Document */

/* ===== Base ===== */
:root{
  --max: 980px;
  --bg: #ffffff;
  --text: #111;
  --muted: #555;
  --line: #e6e6e6;
  --accent: #0a5bd3;
  --accent-weak: #e8f0ff;
  --warn: #fff7e6;
  --warn-line: #f0d7a2;
  --radius: 14px;
}

*{ box-sizing: border-box; }
html{ scroll-behavior: smooth; }
body{
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Hiragino Kaku Gothic ProN",
               "Noto Sans JP", "Yu Gothic", "Meiryo", sans-serif;
  line-height: 1.75;
}

img{
  max-width: 100%;
  height: auto;
  vertical-align: middle;
}

a{
  color: var(--accent);
  text-decoration: none;
}
a:hover{ text-decoration: underline; }

.skip-link{
  position: absolute;
  left: -9999px;
  top: 8px;
  background: #000;
  color: #fff;
  padding: 8px 10px;
  border-radius: 8px;
}
.skip-link:focus{ left: 8px; z-index: 9999; }

/* ===== Layout ===== */
.wrapper{
  width: min(100%, var(--max));
  margin: 0 auto;
  padding: 18px 14px 60px;
}

.page-header{
  border-bottom: 1px solid var(--line);
  padding-bottom: 18px;
  margin-bottom: 18px;
}

.meta-row{
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  align-items: center;
  margin: 6px 0 10px;
}

.updated{
  font-size: 0.95rem;
  color: var(--muted);
}

.page-title{
  font-size: clamp(1.6rem, 2.2vw, 2.2rem);
  line-height: 1.25;
  margin: 10px 0 10px;
  letter-spacing: .02em;
}

.hero{ margin: 10px 0 0; }

/* ===== Breadcrumb ===== */
.breadcrumb{
  font-size: 0.95rem;
  color: var(--muted);
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
}
.breadcrumb a{ color: var(--muted); }
.breadcrumb a:hover{ color: var(--accent); }

/* ===== Sections ===== */
.content{
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 16px;
  margin: 16px 0;
}

.heading{
  font-size: 1.25rem;
  margin: 0 0 10px;
  line-height: 1.35;
}

.heading-note{
  font-size: 0.95rem;
  color: var(--muted);
  font-weight: normal;
  margin-left: 6px;
}

.subheading{
  font-size: 1.05rem;
  margin: 14px 0 8px;
  font-weight: 700;
}

.small{ font-size: 0.95rem; color: var(--text); }
.muted{ color: var(--muted); }
.mini-link{ margin-top: 10px; }

.figure{ margin: 10px 0 12px; }
.caption{
  font-size: 0.92rem;
  color: var(--muted);
  margin-top: 6px;
}

.frame{
  border-radius: 12px;
  border: 1px solid var(--line);
  padding: 6px;
  background: #fafafa;
}

/* ===== Notes / Boxes ===== */
.note{
  border-radius: 12px;
  padding: 12px 12px;
  margin: 14px 0 0;
  border: 1px solid var(--line);
}
.note--warning{
  background: var(--warn);
  border-color: var(--warn-line);
}

.box{
  border: 1px solid var(--line);
  background: #fafafa;
  border-radius: 12px;
  padding: 12px 12px;
  margin: 12px 0;
}

/* ===== TOC ===== */
.toc{
  list-style: none;
  padding: 0;
  margin: 8px 0 0;
  display: grid;
  gap: 8px;
}
.toc a{
  display: block;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: #fff;
}
.toc a:hover{
  background: var(--accent-weak);
  text-decoration: none;
  border-color: #cfe0ff;
}

.toc-sub{
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
}

/* ===== Lists ===== */
.bullets{
  padding-left: 1.1em;
  margin: 8px 0 12px;
}
.bullets li{ margin: 4px 0; }

.refs{
  padding-left: 1.2em;
  margin: 8px 0 0;
}
.refs li{ margin: 6px 0; }

/* ===== cp_list (CTA links) ===== */
.cp_list{
  list-style: none;
  padding: 0;
  margin: 14px 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.cp_list a{
  display: inline-block;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  font-weight: 600;
}
.cp_list a:hover{
  background: var(--accent-weak);
  text-decoration: none;
  border-color: #cfe0ff;
}

/* ===== YouTube Responsive ===== */
.youtube{
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  background: #000;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--line);
  margin: 10px 0 12px;
}
.youtube iframe{
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
}

/* ===== Banner ===== */
.banner{
  margin: 12px 0 0;
}
.banner img{
  border-radius: 12px;
  border: 1px solid var(--line);
  background: #fff;
}

/* ===== Footer ===== */
.page-footer{
  margin-top: 26px;
  border-top: 1px solid var(--line);
  padding-top: 16px;
  font-size: 0.95rem;
}

/* ===== Tables (basic safe) ===== */
table{
  width: 100%;
  border-collapse: collapse;
  overflow: auto;
}
th, td{
  border: 1px solid var(--line);
  padding: 8px 10px;
  vertical-align: top;
}
th{
  background: #f6f6f6;
  text-align: left;
}

/* ===== Mobile fine-tuning ===== */
@media (max-width: 640px){
  .wrapper{ padding: 14px 10px 50px; }
  .content{ padding: 16px 12px; }
  .cp_list{ gap: 8px; }
  .cp_list a{ width: 100%; text-align: center; }
}