:root {
  --navy: #003a73;
  --navy-dark: #002a54;
  --blue: #009fe6;
  --blue-soft: #e3f4fd;
  --ink: #1c2b36;
  --gray: #5b6b78;
  --line: #dde5ec;
  --bg: #f5f8fa;
  --white: #ffffff;
  --accent: #ff7a45;
  --green: #2bb673;
  --red: #e0443a;
  --radius: 14px;
  --shadow: 0 2px 12px rgba(0, 42, 84, 0.08);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: 'Noto Sans JP', 'Inter', sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.8;
}

.container { max-width: 980px; margin: 0 auto; padding: 0 20px; }

/* ---------- header / hero(シリーズ共通) ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: var(--navy);
  box-shadow: 0 2px 8px rgba(0,0,0,.15);
}
.header-inner {
  max-width: 980px; margin: 0 auto; padding: 0 20px;
  display: flex; align-items: center; justify-content: space-between;
  height: 58px;
}
.logo { color: #fff; font-weight: 900; font-size: 18px; display: flex; align-items: center; gap: 10px; }
.logo-mark {
  display: inline-flex; align-items: center; justify-content: center;
  width: 30px; height: 30px; border-radius: 8px;
  background: var(--blue); color: #fff; font-weight: 800; font-size: 15px;
}
.nav { display: flex; gap: 4px; flex-wrap: wrap; align-items: center; }
.nav a {
  color: #cfe3f5; text-decoration: none; font-size: 13px; font-weight: 500;
  padding: 6px 12px; border-radius: 999px; transition: .15s;
}
.nav a:hover { background: rgba(255,255,255,.14); color: #fff; }
.nav .nav-home {
  background: rgba(255,255,255,.14); color: #fff; font-weight: 700;
  border: 1px solid rgba(255,255,255,.25);
}
.nav .nav-home:hover { background: var(--blue); border-color: var(--blue); }

.hero {
  background: linear-gradient(135deg, var(--navy) 0%, #00518f 70%, #0070b8 100%);
  color: #fff; padding: 64px 0 56px;
}
.hero-eyebrow {
  font-family: 'Inter', sans-serif; font-weight: 600; font-size: 12px;
  letter-spacing: .22em; color: #7fd0f5; margin: 0 0 10px;
}
.hero h1 { font-size: 40px; font-weight: 900; margin: 0 0 16px; letter-spacing: .02em; }
.hero-lead { font-size: 15px; color: #d7e7f5; margin: 0 0 28px; }
.hero-lead strong { color: #fff; }
.hero-steps { display: flex; gap: 10px; flex-wrap: wrap; }
.step-chip {
  background: rgba(255,255,255,.12); border: 1px solid rgba(255,255,255,.3);
  color: #fff; text-decoration: none; font-size: 13px; font-weight: 700;
  padding: 8px 16px; border-radius: 999px; transition: .15s;
}
.step-chip:hover { background: var(--blue); border-color: var(--blue); }

/* ---------- lesson(共通) ---------- */
.lesson {
  background: var(--white); border-radius: var(--radius);
  box-shadow: var(--shadow); padding: 36px 36px 32px; margin: 36px 0;
}
.lesson-head { display: flex; align-items: center; gap: 14px; margin-bottom: 8px; }
.step-badge {
  background: var(--blue); color: #fff;
  font-family: 'Inter', sans-serif; font-weight: 800; font-size: 12px;
  letter-spacing: .08em; padding: 4px 12px; border-radius: 999px;
}
.lesson h2 { font-size: 24px; font-weight: 900; color: var(--navy); margin: 0; }
.lesson-desc { color: var(--gray); font-size: 14.5px; margin: 10px 0 20px; }
.lesson-desc strong { color: var(--navy); }
.sub-head { color: var(--navy); font-size: 17px; margin: 32px 0 12px; }

.tips-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 14px; margin-top: 20px;
}
.tip-card { background: var(--bg); border-radius: 10px; padding: 18px 18px 14px; border: 1px solid var(--line); }
.tip-card h3 { font-size: 14.5px; color: var(--navy); margin: 6px 0 6px; }
.tip-card p { font-size: 13px; color: var(--gray); margin: 0; line-height: 1.7; }
.tip-card p strong { color: var(--navy); }

/* ---------- STEP1 ミキサー ---------- */
.mix-row { display: flex; gap: 16px; flex-wrap: wrap; }
.mixer { flex: 1; min-width: 280px; border: 1px solid var(--line); border-radius: 12px; padding: 18px; background: var(--bg); }
.mixer h4 { margin: 0 0 12px; font-size: 14.5px; color: var(--navy); }
.mix-stage {
  position: relative; height: 200px; border-radius: 10px; overflow: hidden; margin-bottom: 12px;
}
.mix-stage.add { background: #0a0a12; }
.mix-stage.sub { background: #ffffff; border: 1px solid var(--line); }
.light, .ink {
  position: absolute; width: 120px; height: 120px; border-radius: 50%;
  transition: opacity .2s;
}
/* 加法混色:screenブレンド */
.light { mix-blend-mode: screen; }
.light.lr { background: #ff0000; top: 24px; left: 50%; transform: translateX(-50%); }
.light.lg { background: #00ff00; bottom: 22px; left: 28%; }
.light.lb { background: #0000ff; bottom: 22px; right: 28%; }
/* 減法混色:multiplyブレンド */
.ink { mix-blend-mode: multiply; }
.ink.lc { background: #00aeef; top: 24px; left: 50%; transform: translateX(-50%); }
.ink.lm { background: #ec008c; bottom: 22px; left: 28%; }
.ink.ly { background: #fff200; bottom: 22px; right: 28%; }
.light.off, .ink.off { opacity: 0; }

.mix-toggles { display: flex; gap: 8px; flex-wrap: wrap; }
.mt {
  font-family: inherit; font-size: 12.5px; font-weight: 700; cursor: pointer;
  border: 1.5px solid var(--line); background: #fff; color: var(--gray);
  border-radius: 999px; padding: 6px 14px; transition: .12s;
}
.mt.on { border-color: var(--navy); background: var(--navy); color: #fff; }
.mix-note { font-size: 12.5px; color: var(--gray); margin: 12px 0 0; line-height: 1.7; }
.mix-note strong { color: var(--navy); }

/* ---------- STEP2 数値 ---------- */
.value-area { display: flex; gap: 20px; align-items: stretch; flex-wrap: wrap; }
.value-swatch {
  flex: 0 0 180px; min-height: 180px; border-radius: 12px; border: 1px solid var(--line);
  background: #009fe6;
}
.value-controls { flex: 1; min-width: 280px; display: flex; flex-direction: column; gap: 12px; justify-content: center; }
.vrow { display: flex; align-items: center; gap: 12px; }
.vlabel {
  width: 26px; height: 26px; flex-shrink: 0; border-radius: 6px; color: #fff;
  font-family: 'Inter',sans-serif; font-weight: 800; font-size: 13px;
  display: flex; align-items: center; justify-content: center;
}
.vlabel.r { background: #e0443a; } .vlabel.g { background: #2bb673; } .vlabel.b { background: #2f6fe0; }
.vrow input[type="range"] { flex: 1; }
#v-r { accent-color: #e0443a; } #v-g { accent-color: #2bb673; } #v-b { accent-color: #2f6fe0; }
.vval { width: 38px; text-align: right; font-family: 'Inter',sans-serif; font-weight: 600; font-size: 13px; color: var(--navy); }
.value-codes { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 6px; }
.code-box {
  flex: 1; min-width: 120px; background: var(--bg); border: 1px solid var(--line);
  border-radius: 8px; padding: 8px 12px;
}
.code-label { display: block; font-size: 11px; color: var(--gray); font-weight: 700; }
.code-val { font-family: 'Inter',sans-serif; font-weight: 700; font-size: 14px; color: var(--navy); }

/* ---------- STEP3 印刷シミュ ---------- */
.print-area { display: flex; gap: 20px; align-items: center; flex-wrap: wrap; }
.print-pair { display: flex; align-items: center; gap: 12px; }
.print-col { text-align: center; }
.print-col span { display: block; font-size: 11.5px; color: var(--gray); font-weight: 700; margin-top: 6px; }
.print-sw { width: 110px; height: 110px; border-radius: 12px; border: 1px solid var(--line); }
.print-arrow { font-weight: 800; color: var(--accent); font-size: 22px; }
.print-meter-wrap { flex: 1; min-width: 240px; }
.hue-row { display: flex; align-items: center; gap: 12px; margin-bottom: 14px; }
.hue-row input[type="range"] {
  flex: 1; accent-color: var(--navy);
  background: linear-gradient(90deg,#f00,#ff0,#0f0,#0ff,#00f,#f0f,#f00); height: 8px; border-radius: 999px;
}
.meter { display: flex; align-items: center; gap: 10px; font-size: 12.5px; font-weight: 700; color: var(--navy); }
.meter-bar { flex: 1; height: 12px; background: var(--line); border-radius: 999px; overflow: hidden; }
#meter-fill { display: block; height: 100%; width: 0; border-radius: 999px; background: linear-gradient(90deg,#2bb673,#ffb02e,#e0443a); transition: width .15s; }
#meter-val { width: 42px; text-align: right; font-family: 'Inter',sans-serif; }
.print-comment { font-size: 13px; color: var(--gray); margin: 12px 0 0; font-weight: 500; min-height: 22px; }
.print-comment strong { color: var(--navy); }

.gallery { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 12px; }
.gcard { border: 1px solid var(--line); border-radius: 10px; overflow: hidden; background: #fff; }
.gcard .gpair { display: flex; height: 64px; }
.gcard .gpair span { flex: 1; }
.gcard .glabel { padding: 8px 10px; font-size: 12px; font-weight: 700; color: var(--navy); }
.gcard .glabel small { display: block; font-weight: 500; color: var(--gray); font-size: 11px; }

/* ---------- クイズ共通 ---------- */
.quiz-box { border: 2px solid var(--line); border-radius: 14px; background: #fff; padding: 26px 28px; }
.quiz-progress {
  display: flex; justify-content: space-between; align-items: center;
  font-family: 'Inter', sans-serif; font-weight: 600; font-size: 13px; color: var(--gray); margin-bottom: 12px;
}
.quiz-q { font-size: 16.5px; font-weight: 900; color: var(--navy); margin-bottom: 16px; line-height: 1.7; }
.quiz-q .q-icon { font-size: 24px; margin-right: 6px; }
.quiz-opts { display: flex; flex-direction: column; gap: 9px; }
.quiz-opt {
  text-align: left; font-family: inherit; font-size: 14.5px; font-weight: 700;
  background: var(--bg); color: var(--ink);
  border: 2px solid var(--line); border-radius: 10px; padding: 11px 18px; cursor: pointer; transition: .12s;
}
.quiz-opt:hover { border-color: var(--blue); background: var(--blue-soft); }
.quiz-opt.is-correct { border-color: var(--green); background: #f2fbf6; color: #1d7a4d; }
.quiz-opt.is-wrong { border-color: var(--red); background: #fdf0ef; color: #b3372f; }
.quiz-opt:disabled { cursor: default; }
.quiz-note { margin-top: 14px; background: var(--blue-soft); border-radius: 10px; padding: 12px 16px; font-size: 13.5px; color: var(--navy); font-weight: 500; }
.quiz-note[hidden] { display: none; }
.quiz-next { margin-top: 14px; }
.quiz-final { text-align: center; padding: 10px 0; }
.quiz-final .qf-score { font-family: 'Inter', sans-serif; font-weight: 800; font-size: 50px; color: var(--navy); }
.quiz-final .qf-score small { font-size: 18px; }
.quiz-final p { margin: 6px 0 14px; font-weight: 900; color: var(--navy); }

.badge-rgb, .badge-cmyk {
  display: inline-block; font-family: 'Inter',sans-serif; font-weight: 800; font-size: 11px;
  border-radius: 6px; padding: 2px 8px; color: #fff;
}
.badge-rgb { background: linear-gradient(90deg,#e0443a,#2bb673,#2f6fe0); }
.badge-cmyk { background: linear-gradient(90deg,#00aeef,#ec008c,#fdb913,#333); }

/* ---------- btn / toast / table / note(共通) ---------- */
.btn {
  font-family: inherit; font-size: 13.5px; font-weight: 700;
  padding: 9px 18px; border-radius: 999px; cursor: pointer;
  border: 1.5px solid var(--line); background: #fff; color: var(--navy); transition: .15s;
}
.btn:hover { border-color: var(--blue); color: var(--blue); }
.btn-primary { background: var(--navy); border-color: var(--navy); color: #fff; }
.btn-primary:hover { background: var(--navy-dark); color: #fff; }

.shortcut-table { width: 100%; border-collapse: collapse; font-size: 13.5px; }
.shortcut-table th, .shortcut-table td { text-align: left; padding: 10px 14px; border-bottom: 1px solid var(--line); }
.shortcut-table th { background: var(--bg); color: var(--navy); font-size: 12.5px; }

.note {
  margin-top: 18px; background: #fff8f0; border: 1px solid #ffd9bd;
  border-radius: 10px; padding: 16px 20px; font-size: 13.5px; color: #6b4a2f;
}
.note strong { color: #b34a14; }

.toast {
  position: fixed; left: 50%; bottom: 28px; transform: translateX(-50%);
  background: var(--navy); color: #fff; font-size: 13.5px; font-weight: 700;
  padding: 10px 22px; border-radius: 999px; box-shadow: 0 6px 20px rgba(0,0,0,.25);
  z-index: 1000; transition: opacity .3s; max-width: 90vw; text-align: center;
}
.toast[hidden] { display: none; }

.site-footer {
  background: var(--navy); color: #9fc0dd; text-align: center;
  padding: 24px 20px; font-size: 12.5px; margin-top: 48px;
}
.site-footer p { margin: 0; }

/* ---------- ページ送りナビ ---------- */
.page-nav { display: flex; gap: 12px; align-items: stretch; margin: 44px auto 0; }
.pgnav { flex: 1; display: flex; flex-direction: column; justify-content: center; gap: 3px;
  text-decoration: none; background: #fff; border: 1.5px solid #dde5ec;
  border-radius: 12px; padding: 14px 18px; transition: .15s; box-shadow: 0 2px 12px rgba(0,42,84,.08); }
.pgnav:hover { border-color: #009fe6; transform: translateY(-2px); }
.pgnav.prev { text-align: left; }
.pgnav.next { text-align: right; }
.pgnav.top { flex: 0 0 130px; text-align: center; background: #003a73; border-color: #003a73; }
.pgnav.top .pgnav-dir, .pgnav.top .pgnav-name { color: #fff; }
.pgnav.top:hover { background: #002a54; border-color: #002a54; }
.pgnav-dir { font-size: 12px; font-weight: 700; color: #ff7a45; }
.pgnav-name { font-size: 14px; font-weight: 900; color: #003a73; }
.pgnav.is-disabled { visibility: hidden; }
@media (max-width: 560px) {
  .page-nav { flex-wrap: wrap; }
  .pgnav.top { order: -1; flex-basis: 100%; }
}

@media (max-width: 700px) {
  .hero h1 { font-size: 27px; }
  .lesson { padding: 24px 18px; }
  .header-inner { flex-direction: column; height: auto; padding: 10px 20px; gap: 4px; }
  .value-swatch { flex-basis: 100%; }
  .print-pair { justify-content: center; width: 100%; }
}