/* Kohana.「扉」改良版 build-06 (2026-11-02, local only).
   1) Space between the first view and 「幸せの手紙」 (only where the letters follow the first view: C and D).
      Cause (build-05, measured): below 64em the first view keeps min-height:100svh although its content is shorter
      (129–263px of empty washi under 「注記の詳細を見る」), and the letters section adds the full section padding
      (88 / 120 / 160px) above its ornament. Fix: the first view ends with its content below 64em, and the letters
      section starts with a smaller padding. PC first view is unchanged (full-height photo).
   2) 「注記の詳細を見る」: marker and open/close animation (fn-accordion.js); the note text itself is not changed. */
@media(max-width:63.99em){
 .fv:has(+ #letters){min-height:0}
}
#top-fv + #letters{padding-top:48px}
@media(min-width:37.5em){#top-fv + #letters{padding-top:64px}}
@media(min-width:64em){#top-fv + #letters{padding-top:96px}}

.fn summary{list-style:none;gap:6px}
.fn summary::-webkit-details-marker{display:none}
.fn summary::before{content:"";order:1;width:7px;height:7px;margin-left:2px;border-right:1.4px solid currentColor;border-bottom:1.4px solid currentColor;
 transform:translateY(-2px) rotate(45deg);transition:transform .32s ease}
.fn[open] summary::before{transform:translateY(1px) rotate(-135deg)}
.fn summary:focus-visible{outline:2px solid var(--cocoa-ink,#4a3a31);outline-offset:3px;border-radius:4px}
.fn .fn-body{overflow:hidden}
.fn .fn-body>p{margin:0;padding-top:4px}
@media(prefers-reduced-motion:reduce){.fn summary::before{transition:none}}
/* PC: the opened note can reach the hero mizuhiki (bottom of the first view); while open it lies on a pale washi panel above it */
@media(min-width:64em){
 .fv .copy:has(.fn[open]){z-index:3}
 .fv .fn .fn-body{margin:2px 0 0 -12px;padding-inline:12px;border-radius:10px;background:rgba(251,246,236,.94)}
 .fv .fn .fn-body>p{padding-block:8px}
}