.site-nav {
  position: relative;
  z-index: 1000;
}

.site-nav-skip {
  position: fixed;
  z-index: 1004;
  top: calc(8px + env(safe-area-inset-top));
  left: 12px;
  padding: 10px 14px;
  border: 2px solid var(--gold);
  border-radius: 10px;
  color: var(--color-night-main);
  background: var(--color-ivory);
  box-shadow: 0 8px 24px rgba(5, 3, 12, 0.36);
  font-weight: 700;
  opacity: 0;
  pointer-events: none;
  text-decoration: none;
  transform: translateY(
    calc(-100% - 32px - env(safe-area-inset-top, 0px))
  );
  transition: transform 160ms ease-out;
}

.site-nav-skip:focus {
  outline: 2px solid var(--color-ivory);
  outline-offset: 3px;
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.koyomi-page button.site-nav-toggle,
.today-page button.site-nav-toggle {
  position: fixed;
  z-index: 1001;
  top: calc(14px + env(safe-area-inset-top));
  right: max(12px, calc((100vw - 640px) / 2 + 12px));
  display: grid;
  width: 48px;
  height: 48px;
  margin: 0;
  padding: 12px;
  place-content: center;
  gap: 5px;
  border: 1px solid var(--color-gold-muted);
  border-radius: 14px;
  color: var(--color-ivory);
  background: var(--bg-card);
  box-shadow: 0 8px 24px rgba(5, 3, 12, 0.36);
  transform: none;
  transition:
    border-color 160ms ease-out,
    background 160ms ease-out;
}

.koyomi-page button.site-nav-toggle:hover,
.today-page button.site-nav-toggle:hover,
.koyomi-page button.site-nav-toggle:active,
.today-page button.site-nav-toggle:active {
  border-color: var(--gold);
  background: var(--color-night-soft);
  transform: none;
}

body.koyomi-page.site-nav-open button.site-nav-toggle,
body.today-page.site-nav-open button.site-nav-toggle {
  visibility: hidden;
  pointer-events: none;
}

.site-nav-toggle-line {
  display: block;
  width: 22px;
  height: 2px;
  border-radius: 999px;
  background: currentColor;
}

.site-nav-backdrop {
  position: fixed;
  z-index: 1002;
  inset: 0;
  background: rgba(20, 16, 31, 0.76);
}

.site-nav-panel {
  position: fixed;
  z-index: 1003;
  top: 0;
  right: 0;
  display: flex;
  flex-direction: column;
  width: min(88vw, 360px);
  height: 100dvh;
  padding:
    calc(18px + env(safe-area-inset-top))
    max(20px, env(safe-area-inset-right))
    calc(24px + env(safe-area-inset-bottom)) 20px;
  overflow: hidden;
  border-left: 1px solid rgba(232, 197, 120, 0.35);
  color: var(--text);
  background: var(--color-night-main);
  box-shadow: -18px 0 42px rgba(5, 3, 12, 0.36);
  visibility: hidden;
  transform: translateX(100%);
  transition:
    transform 180ms ease-out,
    visibility 180ms step-end;
}

.site-nav-panel.is-open {
  visibility: visible;
  transform: translateX(0);
  transition:
    transform 180ms ease-out,
    visibility 0s;
}

.site-nav-panel > nav {
  flex: 1 1 auto;
  min-height: 0;
  overflow-y: auto;
  overscroll-behavior: contain;
}

.site-nav-heading {
  margin: 9px 56px 22px 0;
  color: var(--gold);
  font-family:
    "Shippori Mincho B1", "Yu Mincho", "Hiragino Mincho ProN", serif;
  font-size: 18px;
  line-height: 1.5;
}

.koyomi-page button.site-nav-close,
.today-page button.site-nav-close {
  position: absolute;
  top: calc(14px + env(safe-area-inset-top));
  right: max(14px, env(safe-area-inset-right));
  display: grid;
  width: 44px;
  height: 44px;
  margin: 0;
  padding: 0;
  place-content: center;
  border: 1px solid var(--color-gold-muted);
  border-radius: 13px;
  color: var(--color-ivory);
  background: transparent;
  box-shadow: none;
  transform: none;
  transition:
    border-color 160ms ease-out,
    background 160ms ease-out;
}

.koyomi-page button.site-nav-close:hover,
.today-page button.site-nav-close:hover,
.koyomi-page button.site-nav-close:active,
.today-page button.site-nav-close:active {
  border-color: var(--gold);
  background: var(--color-night-soft);
  transform: none;
}

/* ⚠️ ✕の線は top/left を明示して translate で中央へ固定すること。
   以前は位置指定なしで親の place-content: center に頼っていたが、
   iOS Safari では静的位置（枠の左上の外側）に描かれて見た目が崩壊した
   （2026-08-13 に実機スクリーンショットで発覚。Chromeでは再現しない）。 */
.site-nav-close::before,
.site-nav-close::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 20px;
  height: 2px;
  border-radius: 999px;
  background: currentColor;
}

.site-nav-close::before {
  transform: translate(-50%, -50%) rotate(45deg);
}

.site-nav-close::after {
  transform: translate(-50%, -50%) rotate(-45deg);
}

.site-nav-list {
  display: grid;
  gap: 4px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.site-nav-link,
.koyomi-page button.site-nav-link,
.today-page button.site-nav-link {
  display: flex;
  align-items: center;
  width: 100%;
  min-height: 48px;
  margin: 0;
  padding: 10px 12px;
  border: 1px solid transparent;
  border-radius: 12px;
  color: var(--text);
  background: transparent;
  box-shadow: none;
  font-size: 15px;
  font-weight: 600;
  line-height: 1.5;
  text-align: left;
  text-decoration: none;
  transform: none;
  transition:
    border-color 160ms ease-out,
    background 160ms ease-out;
}

.site-nav-link:hover,
.koyomi-page button.site-nav-link:hover,
.today-page button.site-nav-link:hover,
.site-nav-link:active,
.koyomi-page button.site-nav-link:active,
.today-page button.site-nav-link:active {
  border-color: rgba(232, 197, 120, 0.35);
  color: var(--color-ivory);
  background: var(--color-night-soft);
  transform: none;
}

.site-nav-link[aria-current="page"] {
  border-color: var(--color-gold-muted);
  color: var(--color-ivory);
  background: var(--bg-soft);
}

.site-nav-link[aria-current="page"]::before {
  content: "✦";
  flex: 0 0 auto;
  margin-right: 9px;
  color: var(--gold);
  font-size: 11px;
}

.site-nav-logout {
  cursor: pointer;
}

.site-nav-status {
  margin: 14px 12px 0;
  color: var(--color-ivory);
  font-size: 14px;
  line-height: 1.7;
}

.site-nav-status:empty {
  display: none;
}

.koyomi-page button.site-nav-toggle:focus-visible,
.today-page button.site-nav-toggle:focus-visible,
.koyomi-page button.site-nav-close:focus-visible,
.today-page button.site-nav-close:focus-visible,
.site-nav-link:focus-visible,
.koyomi-page button.site-nav-link:focus-visible,
.today-page button.site-nav-link:focus-visible {
  outline: 2px solid var(--color-ivory);
  outline-offset: 3px;
}

body.site-nav-open {
  overflow: hidden;
}

@media (max-width: 360px) {
  .site-nav-panel {
    width: min(92vw, 340px);
    padding-right: 16px;
    padding-left: 16px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .koyomi-page button.site-nav-toggle,
  .today-page button.site-nav-toggle,
  .koyomi-page button.site-nav-close,
  .today-page button.site-nav-close,
  .site-nav-panel,
  .site-nav-skip,
  .site-nav-link,
  .koyomi-page button.site-nav-link,
  .today-page button.site-nav-link {
    transition: none;
  }
}