/* ============================================================
   what-is-hydrogen.css — 水素とは？ページ専用
   ============================================================ */

/* ── ヒーロー ── */
.wih-hero {
  padding-top: calc(64px + clamp(3.5rem, 7vw, 6rem));
  padding-bottom: clamp(3.5rem, 7vw, 6rem);
  padding-left: var(--pad-x);
  padding-right: var(--pad-x);
  position: relative;
  overflow: hidden;
  background: linear-gradient(160deg, #f8fafc 0%, #edf5fb 60%, #f4f8fc 100%);
  border-bottom: 1px solid var(--border-light);
}
.wih-hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
  overflow: hidden;
}
.wih-molecule {
  position: absolute;
  font-family: 'Cormorant Garamond', serif;
  font-weight: 300;
  color: rgba(74,144,184,.06);
  line-height: 1;
  user-select: none;
}
.wih-molecule--1 { font-size: clamp(6rem, 18vw, 16rem); top: -5%; right: 2%; }
.wih-molecule--2 { font-size: clamp(3rem, 8vw, 8rem); bottom: 10%; left: 3%; }
.wih-molecule--3 { font-size: clamp(2rem, 5vw, 5rem); top: 40%; right: 20%; }

.wih-hero-inner { position: relative; z-index: 1; max-width: var(--max-narrow); }
.wih-h1 {
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 300;
  font-family: var(--font-serif);
  color: var(--navy);
  line-height: 1.35;
  margin-bottom: 1.2rem;
}
.wih-h1-sub {
  font-size: clamp(1.2rem, 2.8vw, 1.8rem);
  color: var(--blue);
  font-style: italic;
  font-family: 'Cormorant Garamond', serif;
  display: block;
}
.wih-lead {
  font-size: clamp(1rem, 1.6vw, 1.1rem);
  color: var(--text-mid);
  font-weight: 300;
  line-height: 1.9;
  margin-bottom: 2.5rem;
  max-width: 520px;
}

/* ── メカニズム図解 ── */
.wih-mechanism {
  margin: 1.5rem 0 2rem;
}
.wih-mechanism-img {
  width: 100%;
  max-width: 480px;
  height: auto;
  display: block;
  margin: 0 auto;
}
.wih-mechanism-caption {
  text-align: center;
  font-size: clamp(.82rem, 1.1vw, .88rem);
  color: var(--muted);
  font-weight: 300;
  line-height: 1.9;
  margin-top: .8rem;
}
.wih-mechanism-caption small { font-size: .75em; opacity: .8; }

/* 目次 */
.wih-toc {
  border: 1px solid var(--border-light);
  background: rgba(255,255,255,.7);
  padding: 1.2rem 1.6rem;
  max-width: 400px;
}
.wih-toc-label {
  font-size: .68rem;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--blue);
  font-weight: 500;
  margin-bottom: .8rem;
}
.wih-toc-list {
  list-style: decimal;
  padding-left: 1.2rem;
  display: flex;
  flex-direction: column;
  gap: .4rem;
}
.wih-toc-list li { color: var(--text-mid); font-size: .88rem; }
.wih-toc-list a {
  color: var(--text-mid);
  transition: color var(--transition);
}
.wih-toc-list a:hover { color: var(--blue); }

/* ── 水素の基本 ── */
.wih-basic-card {
  display: flex;
  gap: 2rem;
  align-items: center;
  padding: 2rem;
  background: var(--navy);
  margin: 2rem 0;
}
.wih-basic-symbol {
  font-family: 'Cormorant Garamond', serif;
  font-size: clamp(3rem, 7vw, 5rem);
  font-weight: 300;
  color: rgba(255,255,255,.3);
  letter-spacing: .05em;
  flex-shrink: 0;
  line-height: 1;
}
.wih-basic-content h3 {
  color: var(--white);
  font-size: clamp(1rem, 1.6vw, 1.2rem);
  margin-bottom: .6rem;
}
.wih-basic-content .body-text { color: rgba(255,255,255,.65); }

.wih-context-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-bottom: 2rem;
}
.wih-context-item {
  padding: 1.2rem 1.4rem;
  border: 1px solid var(--border-light);
  background: var(--off-white);
  transition: border-color var(--transition);
}
.wih-context-item:hover { border-color: var(--blue-light); }
.wih-context-field {
  font-size: .7rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--blue);
  font-weight: 500;
  margin-bottom: .5rem;
}

.wih-note {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
  padding: 1.3rem 1.6rem;
  background: var(--blue-pale);
  border-left: 3px solid var(--blue-light);
  font-size: clamp(.88rem, 1.2vw, .94rem);
  color: var(--text-mid);
  font-weight: 300;
  line-height: 1.9;
}
.wih-note-icon { font-size: 1.1rem; flex-shrink: 0; margin-top: .1rem; }
.wih-note strong { color: var(--navy); font-weight: 500; }

/* ── タイムライン ── */
.wih-timeline {
  margin: 2rem 0;
  display: flex;
  flex-direction: column;
  gap: 0;
}
.wih-timeline-item {
  display: grid;
  grid-template-columns: 100px 1fr;
  gap: 1.5rem;
  align-items: stretch;
  position: relative;
}
.wih-timeline-item + .wih-timeline-item { margin-top: 0; }
.wih-timeline-year {
  font-family: 'Cormorant Garamond', serif;
  font-size: clamp(1rem, 1.8vw, 1.2rem);
  font-weight: 300;
  color: var(--blue);
  padding: 1.2rem 0;
  text-align: right;
  position: relative;
  flex-shrink: 0;
}
.wih-timeline-year::after {
  content: '';
  position: absolute;
  right: -1rem;
  top: 1.5rem;
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--blue);
  border: 2px solid var(--white);
  box-shadow: 0 0 0 1px var(--blue-light);
}
.wih-timeline-content {
  padding: 1.2rem 1.2rem 1.2rem 1.5rem;
  border-left: 1px solid var(--blue-light);
  margin-left: .5rem;
}
.wih-timeline-content h4 {
  font-size: clamp(.95rem, 1.4vw, 1.05rem);
  color: var(--navy);
  margin-bottom: .5rem;
  font-weight: 400;
}

/* 酸化ストレス */
.wih-oxidative {
  margin-top: 2rem;
  padding: 2rem;
  border: 1px solid var(--border);
  background: var(--white);
}
.wih-oxidative h3 {
  font-size: clamp(1rem, 1.6vw, 1.15rem);
  color: var(--navy);
  font-weight: 300;
}
.wih-oxidative-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
}
.wih-oxidative-term {
  font-size: .7rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--blue);
  font-weight: 500;
  margin-bottom: .5rem;
}

.wih-important-box {
  margin-top: 1.5rem;
  padding: 1.3rem 1.6rem;
  background: var(--off-white);
  border: 1px solid var(--border);
  border-left: 3px solid var(--navy);
  font-size: clamp(.88rem, 1.2vw, .94rem);
  color: var(--text-mid);
  font-weight: 300;
  line-height: 1.9;
}
.wih-important-label {
  font-size: .68rem;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--navy);
  font-weight: 500;
  margin-bottom: .5rem;
}
.wih-important-box strong { color: var(--navy); font-weight: 500; }

/* ── 比較表 ── */
.wih-methods-table table {
  width: 100%;
  border-collapse: collapse;
  min-width: 560px;
  font-size: clamp(.82rem, 1.1vw, .9rem);
}
.wih-methods-table thead tr {
  border-bottom: 2px solid var(--border);
}
.wih-methods-table th {
  padding: 1rem .8rem;
  text-align: center;
  font-weight: 300;
  background: var(--off-white);
}
.wih-methods-table th:first-child { background: transparent; }
.wih-methods-table td {
  padding: .9rem .8rem;
  border-bottom: 1px solid var(--border-light);
  line-height: 1.6;
  color: var(--text-mid);
  font-weight: 300;
  text-align: center;
  vertical-align: top;
}
.wih-row-label {
  font-size: .72rem;
  letter-spacing: .1em;
  color: var(--muted);
  font-weight: 400;
  text-align: left !important;
  white-space: nowrap;
  background: var(--off-white);
}
.wih-method-name {
  font-family: var(--font-serif);
  font-size: clamp(1rem, 1.5vw, 1.1rem);
  font-weight: 300;
  color: var(--navy);
  margin-bottom: .2rem;
}
.wih-method-product {
  font-size: .72rem;
  color: var(--muted);
}
.wih-card-note {
  font-size: .75rem;
  color: var(--muted);
  margin-top: 1rem;
  padding-top: .8rem;
  border-top: 1px solid var(--border-light);
  font-weight: 300;
  line-height: 1.7;
}

/* ── 誤解解体 ── */
.wih-misconceptions {
  display: flex;
  flex-direction: column;
  gap: 1.2rem;
  margin-top: 2rem;
}
.wih-misconception-item {
  border: 1px solid var(--border-light);
  overflow: hidden;
  transition: box-shadow var(--transition);
}
.wih-misconception-item:hover { box-shadow: var(--shadow-sm); }
.wih-misconception-head {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem 1.4rem;
  background: var(--off-white);
}
.wih-mis-x {
  font-size: 1.1rem;
  color: #c07820;
  font-weight: 500;
  flex-shrink: 0;
  width: 24px;
  text-align: center;
}
.wih-mis-wrong {
  font-size: clamp(.9rem, 1.3vw, .97rem);
  color: var(--text-mid);
  font-weight: 400;
}
.wih-misconception-body {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
  padding: 1.1rem 1.4rem;
}
.wih-mis-arrow {
  color: var(--blue);
  font-size: 1.1rem;
  flex-shrink: 0;
  margin-top: .2rem;
  width: 24px;
  text-align: center;
}
.wih-mis-correct {
  font-size: .68rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--blue);
  font-weight: 500;
  margin-bottom: .4rem;
}

/* ── 次に読むカード ── */
.wih-next-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.2rem;
  margin-top: 2rem;
}
.wih-next-card {
  display: block;
  padding: 1.5rem;
  border: 1px solid var(--border-light);
  text-decoration: none;
  position: relative;
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}
.wih-next-card:hover {
  border-color: var(--blue-light);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}
.wih-next-tag {
  font-size: .65rem;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--blue);
  font-weight: 500;
  margin-bottom: .5rem;
}
.wih-next-card h3 {
  font-size: clamp(.95rem, 1.4vw, 1.05rem);
  color: var(--navy);
  margin-bottom: .6rem;
  font-weight: 400;
}
.wih-next-card .body-text {
  font-size: clamp(.82rem, 1.1vw, .88rem) !important;
  margin-bottom: 1rem;
}
.wih-next-arrow {
  font-size: .85rem;
  color: var(--blue);
  display: block;
}

/* ── Responsive ── */
@media (max-width: 768px) {
  .wih-context-grid { grid-template-columns: 1fr; }
  .wih-oxidative-grid { grid-template-columns: 1fr; }
  .wih-next-grid { grid-template-columns: 1fr; }
  .wih-basic-card { flex-direction: column; text-align: center; }
}
@media (max-width: 480px) {
  .wih-timeline-item { grid-template-columns: 70px 1fr; }
  .wih-timeline-year { font-size: .9rem; }
  .wih-toc { max-width: 100%; }
}