:root {
  color-scheme: light;
  font-family: Nunito, "Hiragino Maru Gothic ProN", "Yu Gothic UI", Meiryo, system-ui, sans-serif;
  color: #193e32;
  background: #f6faf7;
  --ink: #193e32;
  --muted: #4c6a5e;
  --green: #17684d;
  --mint: #dcf2e6;
  --line: #d6e7dd;
  --soft-line: #e1ece5;
  --paper: #fff;
  --shadow: 0 3px 9px #234b3810;
}

*, *::before, *::after { box-sizing: border-box; }
[hidden] { display: none !important; }
body { margin: 0; min-inline-size: 0; }
button, input, select { font: inherit; }
button, select { cursor: pointer; }
button { color: inherit; }
a { color: var(--green); }
p, h1, h2 { margin: 0; }
button, a, input, select, summary { -webkit-tap-highlight-color: transparent; }
:focus-visible { outline: 3px solid #137251; outline-offset: 3px; }
button:disabled { cursor: default; opacity: .55; }

.visually-hidden {
  position: absolute;
  inline-size: 1px;
  block-size: 1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
}

.skip-link {
  position: fixed;
  z-index: 5;
  inset: .5rem auto auto .5rem;
  padding: .8rem 1rem;
  transform: translateY(-160%);
  background: var(--paper);
  border-radius: .5rem;
}
.skip-link:focus { transform: none; }

.topbar { background: var(--paper); border-block-end: 1px solid var(--soft-line); }
.topbar-inner {
  max-inline-size: 87.5rem;
  min-block-size: 4rem;
  margin-inline: auto;
  padding: .5rem clamp(1rem, 4vw, 3rem);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.brand { display: flex; align-items: center; gap: .65rem; font-size: 1.4rem; font-weight: 850; letter-spacing: .035em; }
.brand small { font-size: .64em; font-weight: 650; color: var(--muted); letter-spacing: 0; }
.brand-mark { position: relative; inline-size: 2.35rem; block-size: 2.35rem; flex: none; background: #d9f2e3; border-radius: .8rem; }
.brand-mark i { position: absolute; inline-size: .94rem; block-size: .72rem; border-radius: 45%; background: #227354; }
.brand-mark i:first-child { inset: .58rem auto auto .43rem; }
.brand-mark i:last-child { inset: auto .41rem .55rem auto; background: #69ab87; }
.brand-mark i::after {
  content: "";
  position: absolute;
  inset: auto auto -.11rem .17rem;
  border: .18rem solid transparent;
  border-block-start-color: #227354;
  transform: rotate(22deg);
}
.brand-mark i:last-child::after { inset-inline: auto .12rem; border-block-start-color: #69ab87; transform: rotate(-22deg); }

.main-nav { display: flex; align-items: center; gap: .45rem; }
.nav-item {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .55rem;
  min-block-size: max(44px, 2.75rem);
  padding: .4rem 1rem;
  border: 1px solid transparent;
  border-radius: .8rem;
  background: transparent;
  color: var(--muted);
  font-weight: 750;
}
.nav-item[aria-pressed="true"] { color: var(--green); background: var(--mint); border-color: #a9d5bc; }
.nav-item[aria-pressed="true"]::after { content: ""; inline-size: .32rem; block-size: .32rem; border-radius: 50%; background: currentColor; }
.nav-star { font-size: 1.35em; line-height: 1; }

.workspace { max-inline-size: 87.5rem; margin-inline: auto; padding: 1.35rem clamp(1rem, 4vw, 3rem) 6.25rem; }
.browse { min-inline-size: 0; }
h1 { font-size: clamp(1.7rem, 4.5vw, 2.25rem); font-weight: 850; letter-spacing: .015em; line-height: 1.35; margin-block-end: .85rem; }
.storage-note { font-size: .9rem; line-height: 1.6; color: var(--muted); margin-block: -.35rem .75rem; }
.search-box {
  display: flex;
  align-items: center;
  gap: .75rem;
  min-block-size: max(52px, 3.25rem);
  border: 1.5px solid #accbbb;
  border-radius: .85rem;
  background: var(--paper);
  padding-inline: .95rem .24rem;
}
.search-box:focus-within { border-color: var(--green); box-shadow: 0 0 0 2px #abd6c1; }
.search-box > .search-icon { color: var(--green); }
.search-icon { flex: none; position: relative; display: inline-block; inline-size: .92em; block-size: .92em; border: 2px solid currentColor; border-radius: 50%; }
.search-icon::after { content: ""; position: absolute; inline-size: .43em; block-size: 2px; inset: auto -.34em -.13em auto; background: currentColor; transform: rotate(46deg); border-radius: 2px; }
.search-box input { flex: 1; min-inline-size: 0; min-block-size: 48px; padding: .65rem .3rem; border: 0; outline: 0; background: transparent; color: var(--ink); font-size: 1.075rem; }
.search-box input::placeholder { color: #526f62; opacity: 1; }
.search-box input::-webkit-search-cancel-button { appearance: none; }

.scenes { margin-block: 1.05rem .8rem; }
.scenes h2 { font-size: .94rem; font-weight: 800; margin-block-end: .48rem; }
.scene-list { display: flex; flex-wrap: wrap; gap: .38rem; }
.scene-button {
  min-block-size: max(44px, 2.75rem);
  min-inline-size: 44px;
  padding: .42rem .82rem;
  background: var(--paper);
  border: 1px solid #bcd6c7;
  border-radius: 1.45rem;
  color: #315a49;
  font-size: .91rem;
  font-weight: 750;
  line-height: 1.3;
}
.scene-button[aria-pressed="true"] { color: #fff; border-color: var(--green); background: var(--green); }
.scene-button[aria-pressed="true"]::before { content: "✓"; display: inline-block; margin-inline-end: .31em; }

.result-bar { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: .35rem .55rem; margin-block-end: .45rem; }
.result-meta { flex: 1 1 4rem; min-inline-size: 0; }
.result-count { font-size: .95rem; color: var(--muted); white-space: nowrap; }
.result-count strong { font-size: 1.2em; font-weight: 850; color: var(--ink); margin-inline-end: .12em; }
.conditions { color: var(--muted); font-size: .82rem; overflow-wrap: anywhere; line-height: 1.4; }
.result-actions { display: flex; gap: .42rem; flex-wrap: wrap; align-items: center; }
.text-button { min-block-size: 44px; padding: .25rem .45rem; background: none; border: 0; color: var(--green); font-weight: 750; text-decoration: underline; text-underline-offset: .19em; font-size: .84rem; }
.about-trigger { text-align: end; }
.sort select {
  max-inline-size: 100%;
  min-block-size: max(44px, 2.75rem);
  border: 1px solid var(--line);
  border-radius: .65rem;
  background: var(--paper);
  color: var(--ink);
  padding: .35rem .45rem .35rem .6rem;
  font-size: .87rem;
}

.word-list { margin: 0; padding: 0; list-style: none; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: .72rem; }
.word-card {
  position: relative;
  display: flex;
  min-inline-size: 0;
  border: 1.5px solid var(--line);
  border-radius: 1.1rem;
  background: var(--paper);
  box-shadow: var(--shadow);
}
.word-card.is-selected { border: 2px solid #28835e; background: #e9f7ef; }
.word-select {
  inline-size: 100%;
  min-block-size: 8.65rem;
  min-inline-size: 0;
  border: 0;
  border-radius: inherit;
  padding: .55rem .28rem .7rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  background: transparent;
}
.word-art { inline-size: min(5.6rem, 100%); block-size: auto; aspect-ratio: 6 / 5; object-fit: contain; margin-block: .12rem .17rem; }
.card-word { max-inline-size: 100%; font-size: clamp(1.15rem, 5.45vw, 1.58rem); font-weight: 850; line-height: 1.22; overflow-wrap: anywhere; }
.card-spelling { max-inline-size: 100%; font-size: .77rem; color: var(--muted); line-height: 1.35; min-block-size: 1em; margin-block-start: .2rem; overflow-wrap: anywhere; }
.card-selected { position: absolute; inset: .4rem auto auto .42rem; padding: .18rem .34rem; color: #14543e; background: #d3eddf; border-radius: .38rem; font-size: .7rem; font-weight: 800; pointer-events: none; }
.icon-button { min-inline-size: max(44px, 2.75rem); min-block-size: max(44px, 2.75rem); display: inline-grid; place-items: center; padding: .3rem; border: 1px solid transparent; border-radius: .72rem; background: transparent; color: var(--green); }
.card-favorite { position: absolute; inset: .19rem .18rem auto auto; }
.favorite-star { font-size: 1.47em; line-height: 1; color: #31664e; }
.card-favorite[aria-pressed="true"] .favorite-star, #lesson-favorite[aria-pressed="true"] .favorite-star { color: #84530f; }
.empty-results { border: 1px dashed #afcdbb; background: var(--paper); padding: 1.55rem 1rem; border-radius: 1rem; color: var(--muted); line-height: 1.75; text-align: center; }

.site-about {
  inline-size: min(42rem, calc(100% - 2rem));
  max-block-size: calc(100dvh - 2rem);
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 1.15rem;
  color: var(--ink);
  background: var(--paper);
  box-shadow: var(--shadow);
  overscroll-behavior: contain;
}
.site-about::backdrop { background: #193e3255; }
body:has(.site-about[open]) { overflow: hidden; }
.about-bar {
  position: sticky;
  z-index: 1;
  inset-block-start: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: .7rem;
  padding: .7rem 1rem;
  border-block-end: 1px solid var(--line);
  background: var(--paper);
}
.about-bar h2 { font-size: 1.2rem; line-height: 1.4; }
.about-bar form { flex: none; }
.about-content { padding: 1rem 1rem 1.25rem; line-height: 1.7; overflow-wrap: anywhere; }
.about-content h3 { margin: 1.15rem 0 .25rem; font-size: 1.02rem; }
.about-content p + p { margin-block-start: .65rem; }
.about-content ul { margin-block: .25rem 0; padding-inline-start: 1.3rem; }

.lesson-rail { display: none; }
.lesson-desktop-bar { display: flex; min-block-size: 44px; gap: .75rem; align-items: center; justify-content: space-between; }
.lesson-desktop-bar h2 { display: flex; align-items: center; gap: .55rem; font-size: 1rem; font-weight: 850; }
.film-icon { position: relative; display: inline-grid; place-items: center; inline-size: 1.22rem; block-size: .92rem; border: 1.6px solid #348765; color: #348765; border-radius: .22rem; }
.film-icon::after, .play-icon { content: ""; inline-size: 0; block-size: 0; border-block: .21rem solid transparent; border-inline-start: .31rem solid currentColor; }
.lesson-empty { display: grid; place-content: center; justify-items: center; gap: 1rem; min-block-size: 18rem; padding: 1.2rem; border-radius: 1rem; background: #ecf7f0; border: 1px dashed #c1dece; text-align: center; }
.lesson-empty p { font-size: 1.02rem; color: #365c4c; font-weight: 750; line-height: 1.6; }
.empty-illustration { display: grid; place-items: center; inline-size: 4.4rem; block-size: 4.4rem; border-radius: 50%; background: #d4eddf; color: #388667; box-shadow: 0 0 0 .55rem #e2f2e8; }
.empty-illustration .play-icon { border-block-width: .64rem; border-inline-start-width: .9rem; margin-inline-start: .19rem; }
.close-button { background: #eff7f2; border-color: #d8e9de; flex: none; }
.cross { position: relative; display: inline-block; inline-size: 1.12em; block-size: 1.12em; }
.cross::before, .cross::after { position: absolute; content: ""; inset: 48% 0 auto; block-size: 2px; border-radius: 2px; background: currentColor; transform: rotate(45deg); }
.cross::after { transform: rotate(-45deg); }
.back-icon { border: solid currentColor; border-width: 0 0 2px 2px; inline-size: .52em; block-size: .52em; transform: rotate(45deg); }

.mobile-lesson {
  margin: 0;
  padding: 0;
  inset: 0;
  border: 0;
  inline-size: 100%;
  block-size: 100dvh;
  max-inline-size: none;
  max-block-size: none;
  color: var(--ink);
  background: #f6faf7;
  overflow: auto;
  overscroll-behavior: contain;
}
.mobile-lesson::backdrop { background: #193e3255; }
.dialog-open { position: fixed; inset: calc(-1 * var(--page-scroll)) 0 auto; inline-size: 100%; }
.mobile-lesson-bar {
  position: sticky;
  z-index: 1;
  inset-block-start: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: .45rem;
  padding: max(.5rem, env(safe-area-inset-top)) 1rem .5rem;
  border-block-end: 1px solid var(--soft-line);
  background: var(--paper);
}
.mobile-lesson-bar .back-button { padding-inline: .5rem .65rem; border: 1px solid transparent; color: var(--green); background: transparent; }
.mobile-lesson-bar .close-button { min-inline-size: 48px; min-block-size: 48px; }
#mobile-lesson-content { padding: .85rem clamp(.625rem, 3vw, 1.3rem) max(1.25rem, env(safe-area-inset-bottom)); }

.lesson { min-inline-size: 0; }
.player-frame { display: grid; place-items: center; min-block-size: 200px; inline-size: 100%; aspect-ratio: 16 / 9; background: #18382e; color: #fff; scroll-margin-block: 4.2rem 1rem; }
.player-frame iframe { display: block; grid-area: 1 / 1; inline-size: 100%; block-size: 100%; min-block-size: 200px; border: 0; }
.player-status { display: flex; flex-wrap: wrap; align-items: center; gap: .4rem .8rem; padding: .65rem .72rem; margin-block-start: .6rem; background: #e7f4eb; border: 1px solid #cfe6d8; border-radius: .68rem; color: #254e3d; font-size: .87rem; }
.player-status p { flex: 1 1 12rem; line-height: 1.55; overflow-wrap: anywhere; }
.timing-note { margin-block-start: .6rem; padding-inline: .4rem; color: var(--muted); font-size: .87rem; line-height: 1.6; }
.lesson-details { padding: .9rem .4rem .6rem; }
.lesson-title { display: flex; flex-wrap: wrap; align-items: baseline; gap: .15rem .65rem; margin-block-end: .7rem; }
.lesson-title h2 { font-size: clamp(1.7rem, 6vw, 2.15rem); font-weight: 850; line-height: 1.35; overflow-wrap: anywhere; }
.lesson-title span { font-size: .93rem; color: var(--muted); }
.lesson-actions { display: flex; gap: .48rem; flex-wrap: wrap; }
.button { display: inline-flex; align-items: center; justify-content: center; gap: .5rem; min-block-size: max(44px, 2.75rem); padding: .48rem .78rem; border-radius: .7rem; border: 1px solid transparent; font-weight: 800; line-height: 1.35; }
.primary-button { background: var(--green); color: #fff; border-color: var(--green); }
.secondary-button { background: var(--paper); color: #265a44; border-color: #bad7c6; }
#lesson-favorite[aria-pressed="true"] { background: #fff7e6; border-color: #b79056; }
.replay-icon { font-size: 1.36em; line-height: 1; }
.publisher { margin-block-start: .9rem; font-size: .86rem; color: var(--muted); line-height: 1.5; }
.publisher a { display: inline-flex; align-items: center; min-block-size: 44px; font-weight: 750; margin-inline-start: .35em; }
.lesson-links { display: flex; flex-wrap: wrap; column-gap: .85rem; }
.lesson-link { display: inline-flex; align-items: center; min-block-size: 44px; gap: .35em; text-decoration-thickness: 1px; text-underline-offset: .19em; font-size: .91rem; font-weight: 750; overflow-wrap: anywhere; }
.lesson-link span { font-weight: 500; }
.review { margin-block-start: .35rem; border-block-start: 1px solid var(--soft-line); font-size: .84rem; color: var(--muted); }
.review summary { min-block-size: 44px; padding-block: .8rem; font-weight: 800; cursor: pointer; }
.review p { line-height: 1.65; margin-block-end: .4rem; }

@media (hover: hover) {
  .word-card:hover { border-color: #8fc1a7; }
  .word-card.is-selected:hover { border-color: #28835e; }
  .nav-item:not([aria-pressed="true"]):hover, .icon-button:hover, .scene-button:not([aria-pressed="true"]):hover { background: #eaf6ef; }
  .primary-button:not(:disabled):hover { background: #0e563d; }
  .secondary-button:hover { background: #eff8f2; }
}

@media (max-width: 999px) {
  .main-nav {
    position: fixed;
    z-index: 2;
    inset: auto 0 0;
    justify-content: center;
    gap: .25rem;
    padding: .35rem max(.75rem, env(safe-area-inset-right)) max(.35rem, env(safe-area-inset-bottom)) max(.75rem, env(safe-area-inset-left));
    border-block-start: 1px solid var(--line);
    background: var(--paper);
    box-shadow: 0 -3px 16px #234b380d;
  }
  .nav-item { flex: 1 1 0; max-inline-size: 17rem; flex-wrap: wrap; padding-inline: .35rem; font-size: .88rem; }
  .word-list { max-inline-size: 42rem; }
}

@media (min-width: 1000px) {
  .topbar { position: sticky; z-index: 2; inset-block-start: 0; }
  .topbar-inner { min-block-size: 4.55rem; }
  .main-nav { margin-inline-start: auto; }
  .workspace { display: grid; grid-template-columns: minmax(0, 55fr) minmax(0, 45fr); gap: clamp(1.15rem, 2.6vw, 2.5rem); align-items: start; padding-block: 1.95rem 3rem; }
  .word-list { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: .85rem; }
  .word-select { min-block-size: 9.5rem; padding-block-start: .75rem; }
  .word-art { inline-size: min(6rem, 100%); }
  .card-word { font-size: clamp(1.12rem, 1.8vw, 1.55rem); }
  .lesson-rail {
    display: block;
    position: sticky;
    inset-block-start: 5.35rem;
    max-block-size: calc(100dvh - 6rem);
    overflow: auto;
    min-inline-size: 0;
    border: 1px solid var(--line);
    background: var(--paper);
    border-radius: 1.15rem;
    padding: .6rem .85rem .85rem;
    box-shadow: var(--shadow);
  }
  .lesson-desktop-bar { margin-block-end: .42rem; }
  .lesson-details { padding: .9rem .2rem .15rem; }
}