/* ============================================================
   Excel Exam — Design tokens & shared styles
   方向性: 白いワークシート × 学習ラボ
   構造=Excelグリーン / 注意=コーラル / 発見=アンバー
   ============================================================ */

:root {
  /* sheet & ink */
  --paper: #f6faf7;
  --paper-2: #edf4ef;
  --card: #ffffff;
  --ink: #1f2a24;
  --ink-soft: #516158;
  --ink-faint: #7c8a82;

  /* 構造: Excelのグリーン */
  --green: #16834c;
  --green-deep: #075f36;
  --green-tint: #ddf3e6;

  /* 動き・注意・発見 */
  --live: #df5b3f;
  --live-soft: #f0a08f;
  --live-tint: #fde9e3;
  --amber: #d98c00;
  --amber-tint: #fff0c7;
  --blue: #2f6fbe;
  --blue-tint: #e5efff;

  /* lines */
  --line: #d6e1d9;
  --line-strong: #b7c7bd;

  --radius: 14px;
  --radius-sm: 8px;
  --shadow-sm: 0 1px 0 rgba(31, 42, 36, 0.04), 0 3px 10px rgba(31, 42, 36, 0.06);
  --shadow: 0 2px 6px rgba(31, 42, 36, 0.06), 0 18px 46px -24px rgba(31, 42, 36, 0.34);
  --focus-ring: 0 0 0 3px rgba(240, 160, 143, 0.45);

  --font-display: "Zen Maru Gothic", "Hiragino Maru Gothic ProN", sans-serif;
  --font-body: "Zen Kaku Gothic New", "Hiragino Sans", "Noto Sans JP", sans-serif;
  --font-mono: "IBM Plex Mono", "SFMono-Regular", Menlo, monospace;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--ink);
  background-color: var(--paper);
  background-image:
    linear-gradient(rgba(22, 131, 76, 0.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(22, 131, 76, 0.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(47, 111, 190, 0.05), transparent 36%, transparent 64%, rgba(217, 140, 0, 0.05));
  background-size: 28px 28px, 28px 28px, 100% 100%;
  background-position: -1px -1px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  -webkit-tap-highlight-color: rgba(29, 122, 81, 0.14);
}

a { color: inherit; }

a,
button {
  touch-action: manipulation;
}

.skip-link {
  position: fixed;
  top: 0.75rem;
  left: 0.75rem;
  z-index: 20;
  transform: translateY(-140%);
  background: var(--ink);
  color: var(--card);
  border-radius: var(--radius-sm);
  padding: 0.55rem 0.8rem;
  font-weight: 700;
  text-decoration: none;
  transition: transform 0.15s ease;
}
.skip-link:focus-visible { transform: translateY(0); }

:where(a, button, input, textarea, select, [tabindex]):focus-visible {
  outline: 3px solid var(--live-soft);
  outline-offset: 3px;
  box-shadow: var(--focus-ring);
}

/* ---------- nav ---------- */
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  position: sticky;
  top: 0;
  z-index: 15;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0.8rem 1.5rem;
  min-width: 0;
  background: rgba(246, 250, 247, 0.84);
  border-bottom: 1px solid rgba(214, 225, 217, 0.64);
  backdrop-filter: blur(14px);
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.15rem;
  text-decoration: none;
}
.brand .mark {
  width: 30px;
  height: 30px;
  display: grid;
  place-items: center;
  background: var(--green);
  color: #fff;
  border-radius: 8px;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 1.05rem;
  box-shadow: inset 0 -2px 0 rgba(0, 0, 0, 0.16), var(--shadow-sm);
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.95rem;
  min-width: 0;
}
.nav-links a,
.nav-links .nav-disabled {
  border-radius: 999px;
  color: var(--ink-soft);
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  min-height: 38px;
  padding: 0.35rem 0.75rem;
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.15s, background-color 0.15s;
}
.nav-links a:hover { background: var(--green-tint); color: var(--green-deep); }
.nav-links a[aria-current="page"] {
  background: var(--green);
  color: #fff;
  font-weight: 700;
}
.nav-links .nav-disabled { color: var(--ink-faint); cursor: default; }
.soon {
  border: 1px solid var(--line);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  padding: 0.05rem 0.35rem;
}

/* ---------- hero ---------- */
.hero {
  align-items: center;
  display: grid;
  gap: clamp(1.5rem, 4vw, 3rem);
  grid-template-columns: minmax(0, 1.02fr) minmax(360px, 0.78fr);
  max-width: 1200px;
  margin: 0 auto;
  padding: 2.6rem 1.5rem 2.2rem;
}
.hero-copy {
  min-width: 0;
}
.eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--green-deep);
  background: linear-gradient(90deg, var(--green-tint), var(--blue-tint));
  padding: 0.3rem 0.7rem;
  border-radius: 999px;
  margin-bottom: 1.3rem;
}
.hero h1 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.1rem, 5.5vw, 3.6rem);
  line-height: 1.25;
  letter-spacing: 0.01em;
  margin: 0 0 1.1rem;
}
.hero h1 .accent { color: var(--green); position: relative; }
.hero h1 .accent::after {
  content: "";
  position: absolute;
  left: -2%;
  right: -2%;
  bottom: 0.08em;
  height: 0.32em;
  background: var(--live-tint);
  z-index: -1;
  border-radius: 3px;
}
.hero .lede {
  font-size: clamp(1.02rem, 2vw, 1.2rem);
  color: var(--ink-soft);
  max-width: 46ch;
  margin: 0 0 2rem;
}
.cta-row { display: flex; flex-wrap: wrap; gap: 0.8rem; align-items: center; }

.hero-preview {
  background: rgba(255, 255, 255, 0.92);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  display: grid;
  gap: 0.75rem;
  min-width: 0;
  overflow: hidden;
  padding: 1rem;
  position: relative;
}
.hero-preview::before {
  background: linear-gradient(90deg, var(--green), var(--blue), var(--amber));
  content: "";
  height: 4px;
  inset: 0 0 auto;
  position: absolute;
}
.preview-top {
  display: grid;
  gap: 0.15rem;
  padding-top: 0.2rem;
}
.hero-preview .panel-kicker {
  color: var(--live);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.preview-top strong {
  font-family: var(--font-display);
  font-size: 1.22rem;
  line-height: 1.25;
}
.mini-formula {
  align-items: center;
  background: var(--paper);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  display: grid;
  gap: 0.55rem;
  grid-template-columns: auto minmax(0, 1fr);
  min-width: 0;
  padding: 0.55rem 0.65rem;
}
.mini-formula span {
  color: var(--green-deep);
  font-family: var(--font-mono);
  font-style: italic;
  font-weight: 700;
}
.mini-formula code {
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 0.88rem;
  min-width: 0;
  overflow-wrap: anywhere;
}
.mini-sheet {
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  display: grid;
  font-family: var(--font-mono);
  grid-template-columns: 34px repeat(3, minmax(0, 1fr));
  overflow: hidden;
}
.mini-sheet > * {
  align-items: center;
  background: #fff;
  border-bottom: 1px solid var(--line);
  border-right: 1px solid var(--line);
  display: flex;
  min-height: 40px;
  min-width: 0;
  overflow: hidden;
  padding: 0 0.55rem;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.mini-sheet .mini-head {
  background: var(--paper-2);
  color: var(--ink-faint);
  font-size: 0.78rem;
  justify-content: center;
}
.mini-sheet b {
  background: var(--paper);
  color: var(--ink-soft);
  font-size: 0.82rem;
}
.mini-sheet .is-source {
  background: var(--amber-tint);
  box-shadow: inset 0 0 0 2px rgba(217, 140, 0, 0.38);
}
.mini-sheet .is-result {
  background: var(--green-tint);
  color: var(--green-deep);
  font-weight: 700;
}
.preview-flow {
  align-items: center;
  display: grid;
  gap: 0.5rem;
  grid-template-columns: auto 1fr auto 1fr auto;
}
.preview-flow span {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--green-deep);
  font-size: 0.82rem;
  font-weight: 800;
  padding: 0.22rem 0.6rem;
}
.preview-flow i {
  background: linear-gradient(90deg, var(--green), var(--live-soft));
  display: block;
  height: 2px;
  min-width: 18px;
}

.page-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  align-items: center;
  margin-top: 1.25rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-body);
  font-weight: 700;
  font-size: 1rem;
  text-decoration: none;
  padding: 0.8rem 1.4rem;
  border-radius: 999px;
  border: 1.5px solid transparent;
  cursor: pointer;
  transition: transform 0.12s ease, box-shadow 0.2s ease, background 0.2s;
}
.btn-primary { background: var(--green); color: #fff; box-shadow: var(--shadow-sm); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: var(--shadow); }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--line-strong); }
.btn-ghost:hover { border-color: var(--green); color: var(--green); }
.btn .arrow { transition: transform 0.15s; }
.btn-primary:hover .arrow { transform: translateX(3px); }
.text-link {
  color: var(--green-deep);
  font-weight: 700;
  text-decoration-color: rgba(29, 122, 81, 0.35);
  text-decoration-thickness: 2px;
  text-underline-offset: 0.18em;
}
.text-link:hover { color: var(--live); text-decoration-color: currentColor; }

/* ---------- concept cards: 3つの感覚 ---------- */
.section { max-width: 1200px; margin: 0 auto; padding: 2.7rem 1.5rem; scroll-margin-top: 1rem; }
.section-head { margin-bottom: 1.8rem; }
.section-head .kicker {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  color: var(--live);
  text-transform: uppercase;
}
.section-head h2 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.5rem, 3.5vw, 2.1rem);
  margin: 0.3rem 0 0;
}
.section-head p { color: var(--ink-soft); margin: 0.6rem 0 0; max-width: 52ch; }

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1rem;
}
.route-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1rem;
}
.route-card {
  display: grid;
  gap: 0.45rem;
  min-width: 0;
  background: var(--card);
  border: 1.5px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 1rem;
  text-decoration: none;
  transition: border-color 0.15s, box-shadow 0.2s, transform 0.12s;
}
.route-card:hover {
  border-color: var(--green);
  box-shadow: var(--shadow-sm);
  transform: translateY(-2px);
}
.route-card strong {
  color: var(--ink);
  font-family: var(--font-display);
  font-size: 1.18rem;
}
.route-card span:last-child {
  color: var(--ink-soft);
  font-size: 0.95rem;
}
.route-step {
  color: var(--live);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
}
.route-note {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  background: var(--green-tint);
  border: 1px solid rgba(29, 122, 81, 0.18);
  border-radius: var(--radius-sm);
  color: var(--green-deep);
  margin: 0 0 1rem;
  padding: 0.8rem 1rem;
}
.route-note p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.94rem;
}
.concept-card {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.6rem 1.5rem 1.7rem;
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: transform 0.18s ease, box-shadow 0.25s ease;
}
.concept-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.concept-card .num {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--ink-faint);
}
.concept-card h3 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.25rem;
  margin: 0.4rem 0 0.6rem;
}
.concept-card h3 .em { color: var(--green); }
.concept-card p { margin: 0; color: var(--ink-soft); font-size: 0.96rem; }
.concept-card .glyph {
  font-family: var(--font-mono);
  font-size: 1.05rem;
  color: var(--green);
  background: var(--green-tint);
  border-radius: var(--radius-sm);
  padding: 0.5rem 0.7rem;
  margin-top: 1.1rem;
  display: inline-block;
}
.concept-card::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--green), var(--live-soft));
  opacity: 0;
  transition: opacity 0.25s;
}
.concept-card:hover::before { opacity: 1; }

/* ---------- learning path ---------- */
.path {
  display: grid;
  gap: 0.7rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.path-item {
  position: relative;
}
.path-item:not(:last-child)::after {
  content: "";
  position: absolute;
  left: 25px;
  top: calc(100% - 2px);
  width: 2px;
  height: 0.7rem;
  background: var(--line-strong);
}
.path-step {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto auto;
  align-items: center;
  gap: 1rem;
  background: var(--card);
  border: 1.5px solid var(--line);
  border-radius: 14px;
  color: inherit;
  padding: 0.95rem 1rem;
  text-decoration: none;
  transition: border-color 0.2s, box-shadow 0.2s, transform 0.12s;
}
.path-step:hover {
  border-color: var(--green);
  box-shadow: var(--shadow-sm);
  transform: translateX(4px);
}
.path-step .stage {
  font-family: var(--font-mono);
  font-weight: 600;
  color: #fff;
  background: var(--green);
  width: 30px; height: 30px;
  display: grid; place-items: center;
  border-radius: 8px;
  font-size: 0.85rem;
}
.path-step.hot .stage { background: var(--live); }
.path-copy {
  display: grid;
  min-width: 0;
}
.path-step .label { font-weight: 700; }
.path-step .metaphor { color: var(--ink-soft); font-size: 0.9rem; }
.path-step .grade {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--ink-faint);
  white-space: nowrap;
}
.path-action {
  align-items: center;
  background: var(--green);
  border-radius: 999px;
  color: #fff;
  display: inline-flex;
  font-size: 0.86rem;
  font-weight: 700;
  gap: 0.25rem;
  justify-content: center;
  min-height: 34px;
  padding: 0.25rem 0.8rem;
  white-space: nowrap;
}
.path-action::after {
  content: "→";
  font-family: var(--font-mono);
}
.path-step.hot .path-action {
  background: var(--live);
}

/* ---------- footer ---------- */
.footer {
  max-width: 1200px;
  margin: 2rem auto 0;
  padding: 2rem 1.5rem 3rem;
  border-top: 1px solid var(--line);
  color: var(--ink-faint);
  font-size: 0.88rem;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.redirect-page {
  display: grid;
  min-height: 100vh;
  place-content: center;
  text-align: center;
}
.redirect-page p {
  color: var(--ink-soft);
  margin: 0.35rem 0;
}

@media (max-width: 900px) {
  .hero {
    grid-template-columns: 1fr;
    padding-top: 2rem;
  }
  .hero-preview {
    max-width: 560px;
  }
}

@media (max-width: 560px) {
  .nav {
    align-items: flex-start;
    flex-direction: column;
    padding: 1rem;
  }
  .nav-links {
    gap: 0.35rem;
    overflow-x: auto;
    padding-bottom: 0.2rem;
    width: 100%;
  }
  .nav-links a,
  .nav-links .nav-disabled {
    min-height: 36px;
    padding: 0.3rem 0.65rem;
  }
  .cta-row,
  .page-actions { align-items: stretch; flex-direction: column; }
  .cta-row .btn,
  .page-actions .btn { justify-content: center; width: 100%; }
  .route-grid { grid-template-columns: 1fr; }
  .route-note { align-items: flex-start; flex-direction: column; gap: 0.35rem; }
  .path-step { grid-template-columns: auto 1fr; gap: 0.65rem 0.85rem; }
  .path-step .grade { grid-column: 2; }
  .path-action { grid-column: 2; justify-self: start; }
}