:root {
  --tca-primary: #0f2a4a;
  --tca-accent: #c9a14a;
  --tca-text: #1f2937;
  --tca-muted: #6b7280;
  --tca-border: #e5e7eb;
  --tca-surface: #ffffff;
  --tca-bg: #f6f7f9;
  --tca-link: #1d4ed8;
  --tca-focus: #2563eb;
  --tca-gap-small: .6rem;
  --tca-gap-base: 1rem;
  --tca-gap-large: 1.6rem;
  color-scheme: light;
}
* { box-sizing: border-box; }
html { font-size: 16px; }
body { margin: 0; font-family: system-ui, -apple-system, "Segoe UI", "Hiragino Sans", "Noto Sans JP", sans-serif; color: var(--tca-text); background: var(--tca-bg); line-height: 1.6; }
a { color: var(--tca-link); }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

.tca-header { background: var(--tca-surface); border-bottom: 1px solid var(--tca-border); position: sticky; top: 0; z-index: 10; }
.tca-header__row { display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding: .7rem 1rem; max-width: 1100px; margin: 0 auto; }
.tca-brand { display: inline-flex; align-items: center; text-decoration: none; color: var(--tca-primary); }
.tca-brand img { display: block; height: auto; }
.tca-brand__wide { width: 220px; max-width: 48vw; }
.tca-brand__compact { display: none; width: 56px; }
.tca-brand__text { font-weight: 800; font-size: 1.3rem; letter-spacing: .02em; }
.tca-header__tools { display: flex; align-items: center; gap: .6rem; }
.tca-inline-form { margin: 0; }
.tca-lang select { font: inherit; padding: .4rem .5rem; border: 1px solid var(--tca-border); border-radius: .5rem; background: #fff; }
.tca-btn { display: inline-block; font: inherit; font-weight: 600; padding: .6rem 1rem; border-radius: .6rem; border: 1px solid var(--tca-primary); color: var(--tca-primary); background: #fff; text-decoration: none; cursor: pointer; min-height: 2.6rem; line-height: 1.2; }
.tca-btn--primary { background: var(--tca-primary); color: #fff; }
.tca-btn--ghost { border-color: var(--tca-border); }
.tca-btn:focus-visible, .tca-nav__link:focus-visible, select:focus-visible { outline: 3px solid var(--tca-focus); outline-offset: 2px; }
.tca-menu-toggle { display: none; }
.tca-nav { display: flex; flex-wrap: wrap; gap: .2rem 1.2rem; padding: 0 1rem .6rem; max-width: 1100px; margin: 0 auto; }
.tca-nav__link { color: var(--tca-text); text-decoration: none; padding: .5rem 0; border-bottom: 2px solid transparent; font-size: .95rem; }
.tca-nav__link.is-current { border-bottom-color: var(--tca-accent); font-weight: 700; }
.tca-nav__link:hover { text-decoration: underline; }

.tca-main { max-width: 960px; margin: 0 auto; padding: 1.2rem 1rem 3rem; display: flex; flex-direction: column; gap: 1rem; }
.tca-landing h1 { font-size: 1.8rem; margin: .4rem 0; color: var(--tca-primary); }
.tca-lead { font-size: 1.05rem; }
.tca-note { color: var(--tca-muted); font-size: .9rem; }
.tca-cta-row { display: flex; flex-wrap: wrap; gap: .8rem; }

.tca-footer { border-top: 1px solid var(--tca-border); background: var(--tca-surface); padding: 2rem 1rem; font-size: .9rem; }
.tca-footer__cols { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1.2rem; max-width: 1100px; margin: 0 auto; }
.tca-footer ul { list-style: none; margin: 0; padding: 0; }
.tca-footer li { margin: .35rem 0; }
.tca-footer a { color: var(--tca-text); text-decoration: none; }
.tca-footer a:hover { text-decoration: underline; }
.tca-footer__rights { max-width: 1100px; margin: 1.4rem auto 0; color: var(--tca-muted); }

@media (max-width: 767px) {
  .tca-brand__wide { display: none; }
  .tca-brand__compact { display: block; }
  .tca-menu-toggle { display: inline-block; }
  .tca-nav { display: none; flex-direction: column; gap: 0; }
  .tca-nav.is-open { display: flex; }
  .tca-nav__link { padding: .8rem 0; border-top: 1px solid var(--tca-border); border-bottom: none; }
  .tca-nav__link.is-current { border-left: 3px solid var(--tca-accent); padding-left: .5rem; }
  .tca-footer__cols { grid-template-columns: 1fr; }
  .tca-cta-row .tca-btn { flex: 1 1 100%; text-align: center; }
}