/* うごく世界地図 のデザイントークン。紙とインク、朱のアクセント。地図の面だけが海の色。 */
:root{--paper:#f4efe5;--paper-2:#ece5d7;--paper-3:#e3dbcb;--ink:#28231f;--muted:#655c52;--line:#d7cdbc;--line-strong:#b9ad99;--accent:#b5402c;--accent-ink:#fff6ef;--accent-soft:#f0ddd5;--ocean:#cfdce6;--ocean-deep:#b9cbd8;--grid:rgba(40,35,31,.14);--equator:rgba(40,35,31,.32);--ghost-line:rgba(40,35,31,.45);--label:#28231f;--label-halo:rgba(244,239,229,.85);--focus:#b5402c;--radius:4px;--serif:'Shippori Mincho','Hiragino Mincho ProN','Yu Mincho',serif;--sans:'Noto Sans JP','Hiragino Kaku Gothic ProN','Yu Gothic',sans-serif;--mono:'JetBrains Mono',ui-monospace,'SF Mono',Menlo,monospace;color-scheme:light}
:root[data-theme=dark]{--paper:#171412;--paper-2:#1f1b18;--paper-3:#2a2521;--ink:#ece4d6;--muted:#a69b8d;--line:#3a332c;--line-strong:#564c42;--accent:#d8664f;--accent-ink:#1a110e;--accent-soft:#3a241e;--ocean:#1b2630;--ocean-deep:#141d25;--grid:rgba(236,228,214,.12);--equator:rgba(236,228,214,.3);--ghost-line:rgba(236,228,214,.4);--label:#ece4d6;--label-halo:rgba(23,20,18,.8);--focus:#d8664f;color-scheme:dark}
*{box-sizing:border-box}
html{font-family:var(--sans);color:var(--ink);background:var(--paper);font-synthesis:none;-webkit-text-size-adjust:100%}
body{margin:0;background:var(--paper);transition:background .3s,color .3s;line-height:1.7}
button,input,select{font:inherit}
button,a,input,select{-webkit-tap-highlight-color:transparent}
button{cursor:pointer;min-height:44px;border:1px solid var(--line-strong);border-radius:var(--radius);background:transparent;color:inherit;transition:background .15s,border-color .15s,transform .15s;padding:0 12px}
button:hover{background:var(--paper-3)}
button:active{transform:scale(.97)}
:focus-visible{outline:2px solid var(--focus);outline-offset:3px}
h1,h2,h3{font-family:var(--serif);font-weight:600;margin:0;letter-spacing:.01em}
a{color:inherit}
.eyebrow,.section-label{font-family:var(--mono);font-size:11px;letter-spacing:.18em;text-transform:uppercase;color:var(--muted);font-weight:500}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0)}
ruby rt{font-size:.55em;color:var(--muted);font-weight:400;letter-spacing:0}

header{height:84px;padding:0 4%;display:flex;align-items:center;justify-content:space-between;gap:20px;border-bottom:1px solid var(--line)}
.brand{display:flex;align-items:baseline;gap:14px;color:inherit;text-decoration:none;white-space:nowrap}
.brand-name{font-family:var(--serif);font-size:26px;font-weight:700;letter-spacing:.04em}
.brand-sub{font-family:var(--mono);font-size:10px;letter-spacing:.2em;line-height:1.5;color:var(--muted)}
nav{display:flex;gap:4px;align-items:center;flex:1;justify-content:flex-end;overflow-x:auto;scrollbar-width:none}
nav::-webkit-scrollbar{display:none}
nav a{color:var(--muted);text-decoration:none;padding:12px 14px;font-size:14px;border-radius:var(--radius);min-height:44px;display:inline-flex;align-items:center;white-space:nowrap;transition:background .15s,color .15s}
nav a:hover{background:var(--paper-2);color:var(--ink)}
.theme-toggle{width:44px;padding:0;display:grid;place-items:center;border-color:var(--line);color:var(--muted)}
.theme-toggle svg{width:18px;height:18px}
.theme-toggle .sun{display:none}
:root[data-theme=dark] .theme-toggle .sun{display:block}
:root[data-theme=dark] .theme-toggle .moon{display:none}

main{max-width:1600px;margin:auto;padding:0 4%}

.workspace{display:grid;grid-template-columns:minmax(0,1fr) 340px;border:1px solid var(--line);border-radius:8px;overflow:hidden;background:var(--paper-2)}
.stage{display:grid;grid-template-rows:minmax(0,1fr) auto;min-width:0}
.viewport{position:relative;background:var(--ocean);min-height:560px;overflow:hidden;user-select:none}
#map{position:absolute;inset:0;width:100%;height:100%;display:block;touch-action:none;cursor:grab}
#map.dragging{cursor:grabbing}
.overlay{position:absolute;z-index:2;pointer-events:none}
.regions{top:14px;left:14px;display:flex;gap:4px;flex-wrap:wrap;pointer-events:auto;max-width:calc(100% - 330px)}
.regions button{min-height:36px;padding:0 11px;font-size:13px;background:var(--paper);border-color:var(--line);box-shadow:0 1px 0 rgba(0,0,0,.06)}
.regions button[aria-pressed=true]{background:var(--ink);color:var(--paper);border-color:var(--ink)}
.age-badge{top:14px;right:16px;text-align:right}
.age-badge .age{font-family:var(--serif);font-size:clamp(24px,2.6vw,36px);font-weight:700;line-height:1.1;letter-spacing:.02em;text-shadow:0 0 12px var(--ocean),0 0 2px var(--ocean)}
.age-badge .period{font-size:13px;margin-top:6px;color:var(--ink);text-shadow:0 0 8px var(--ocean)}
.age-badge .period b{font-weight:600}
.age-badge .era{font-family:var(--mono);font-size:10px;letter-spacing:.14em;color:var(--muted);margin-left:8px}
.legend{bottom:12px;left:12px;display:flex;gap:4px 14px;flex-wrap:wrap;font-size:12px;pointer-events:auto;max-width:70%;padding:4px 10px;border-radius:4px;background:color-mix(in srgb,var(--paper) 72%,transparent)}
.legend button{min-height:32px;padding:0 4px 0 0;border:0;background:transparent;font-size:12px;display:inline-flex;align-items:center;gap:6px;color:var(--ink)}
.legend button:hover{background:transparent;text-decoration:underline}
.legend button[aria-pressed=true]{font-weight:700}
.legend i{display:inline-block;width:12px;height:12px;border-radius:2px;background:var(--c);border:1px solid rgba(0,0,0,.15)}
.legend .ghost i{background:transparent;border:1px dashed var(--ghost-line)}
.note{bottom:14px;right:16px;font-size:11px;color:var(--muted);text-align:right;max-width:220px;line-height:1.6}
.note b{color:var(--ink);font-weight:600}
.globe-tools{right:14px;bottom:62px;display:grid;gap:6px;pointer-events:auto}
.globe-tools button{width:40px;min-height:40px;padding:0;background:var(--paper);border-color:var(--line);font-size:18px;line-height:1}
.view-hint{font-size:11px;color:var(--muted);position:absolute;left:16px;bottom:44px;z-index:2;pointer-events:none}

.timeline{padding:12px 16px 14px;border-top:1px solid var(--line);background:var(--paper-2)}
.tl-controls{display:flex;align-items:center;gap:8px;margin-bottom:8px;flex-wrap:wrap}
.tl-controls .play{min-width:92px;background:var(--accent);color:var(--accent-ink);border-color:var(--accent);font-weight:600;letter-spacing:.04em}
.tl-controls .play:hover{background:#9c3524}
:root[data-theme=dark] .tl-controls .play:hover{background:#e3755e}
.tl-controls .step{width:44px;padding:0;font-size:16px}
.speed{display:inline-flex;border:1px solid var(--line-strong);border-radius:var(--radius);overflow:hidden;margin-left:4px}
.speed button{border:0;border-radius:0;min-height:38px;font-size:12px;padding:0 10px;color:var(--muted)}
.speed button+button{border-left:1px solid var(--line-strong)}
.speed button[aria-pressed=true]{background:var(--ink);color:var(--paper)}
.tl-controls .spacer{flex:1}
.tl-controls .kbd{font-family:var(--mono);font-size:10px;color:var(--muted);letter-spacing:.06em}
#timeline{width:100%;height:96px;display:block;touch-action:none;cursor:pointer}
#timeline text{font-family:var(--sans);pointer-events:none}
#timeline .era-label{font-family:var(--mono);font-size:10px;letter-spacing:.14em;fill:var(--muted)}
#timeline .period-label{font-size:11px;fill:#1f1b18}
#timeline .period{stroke:var(--paper);stroke-width:1}
#timeline .ev{fill:var(--ink);opacity:.55}
#timeline .ev.near{opacity:1;fill:var(--accent)}
#timeline .ev-label{font-size:10px;fill:var(--muted)}
#timeline .tick{font-family:var(--mono);font-size:10px;fill:var(--muted);letter-spacing:.06em}
#timeline .handle-line{stroke:var(--ink);stroke-width:2}
#timeline .handle-knob{fill:var(--paper);stroke:var(--ink);stroke-width:2}
#timeline .handle:focus,#timeline .handle:focus-visible{outline:none}
#timeline .handle:focus-visible .handle-knob{stroke:var(--focus);stroke-width:3}

aside{padding:24px 24px 28px;background:var(--paper-2);border-left:1px solid var(--line);min-width:0}
.section-label{margin-bottom:14px}
aside h2{font-size:22px;line-height:1.4}
aside h2 small{font-family:var(--mono);font-size:10px;letter-spacing:.14em;color:var(--muted);margin-left:8px;font-weight:500}
.summary{font-size:14px;line-height:1.95;margin:10px 0 0}
.region-note{font-size:12px;color:var(--muted);line-height:1.8;margin:10px 0 0;padding-top:10px;border-top:1px dashed var(--line)}
.region-note:empty{display:none}
.divider{height:1px;background:var(--line);margin:20px 0}
.events{list-style:none;margin:0;padding:0}
.events li{display:grid;grid-template-columns:76px 1fr;gap:10px;padding:7px 0;font-size:13px;line-height:1.7;border-bottom:1px dashed var(--line)}
.events li:last-child{border-bottom:0}
.events .when{font-family:var(--mono);font-size:11px;color:var(--muted);letter-spacing:.02em;padding-top:3px}
.events button{border:0;padding:4px 0;min-height:32px;text-align:left;background:transparent;font-size:13px;line-height:1.7;color:inherit;display:block}
.events button:hover{background:transparent;text-decoration:underline}
.events li.now .when,.events li.now button{color:var(--accent);font-weight:600}
.events .text{display:block;color:var(--muted);font-size:12px;margin-top:2px;font-weight:400}
.switch-row{display:flex;align-items:center;justify-content:space-between;min-height:40px;font-size:13px;cursor:pointer;gap:10px}
.switch-row input{width:34px;height:20px;accent-color:var(--accent);cursor:pointer;margin:0;flex:none}
.certainty{font-size:12px;color:var(--muted);line-height:1.8}
.certainty b{display:inline-block;font-family:var(--mono);font-size:10px;letter-spacing:.12em;padding:2px 7px;border:1px solid var(--line-strong);border-radius:3px;margin-right:8px;color:var(--ink)}
.certainty[data-level="1"] b{border-color:var(--accent);color:var(--accent)}
.share{display:flex;gap:8px;margin-top:14px}
.share button{flex:1;font-size:13px}

footer{display:flex;justify-content:space-between;border-top:1px solid var(--line);padding:22px 4% 34px;font-family:var(--mono);font-size:11px;color:var(--muted);gap:20px;margin-top:44px;letter-spacing:.04em;flex-wrap:wrap;line-height:1.8}
footer a{color:inherit}
.toast{position:fixed;left:50%;bottom:28px;transform:translate(-50%,20px);background:var(--ink);color:var(--paper);padding:10px 18px;border-radius:4px;font-size:13px;opacity:0;transition:opacity .2s,transform .2s;pointer-events:none;z-index:50}
.toast.show{opacity:1;transform:translate(-50%,0)}
.failure{padding:80px 24px;text-align:center;color:var(--ink)}

@media(min-width:1001px){.workspace{height:clamp(640px,calc(100svh - 150px),920px)}.viewport{min-height:0}.workspace aside{overflow-y:auto;scrollbar-width:thin}}
@media(max-width:1000px){.workspace{grid-template-columns:1fr}aside{border-left:0;border-top:1px solid var(--line)}.viewport{min-height:480px}.age-badge .age{font-size:26px}}
@media(max-width:760px){header{height:auto;min-height:72px;padding:10px 4%;display:grid;grid-template-columns:1fr auto;gap:6px 10px}.brand{grid-column:1}.brand-name{font-size:22px}.theme-toggle{grid-column:2;grid-row:1}nav a{font-size:12px;padding:8px 10px}.viewport{min-height:62svh}.regions{top:10px;left:10px;flex-wrap:nowrap;overflow-x:auto;scrollbar-width:none;max-width:calc(100% - 150px)}.regions::-webkit-scrollbar{display:none}.regions button{flex:none}.regions button{min-height:34px;padding:0 9px;font-size:12px}.age-badge{top:10px;right:12px}.age-badge .age{font-size:22px}.age-badge .period{font-size:11px}.regions{max-width:calc(100% - 150px)}.globe-tools{top:92px}.legend{bottom:10px;left:10px;gap:8px;font-size:11px;max-width:100%}.legend button{font-size:11px;min-height:24px}.note{display:none}.globe-tools{right:10px;bottom:auto}.view-hint{display:none}.timeline{padding:10px 10px 12px}#timeline{height:88px}.tl-controls .kbd{display:none}aside{padding:20px 16px 24px}footer{flex-direction:column;gap:8px}}
@media(prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important}}

/* 教材の切り替え（大陸の動き / 国の成り立ち）。ページの主役なので大きく */
.switch-tabs{display:flex;gap:0;border:1px solid var(--line-strong);border-radius:6px;overflow:hidden;flex:none;margin:0 auto}
.switch-tabs a{display:flex;flex-direction:column;justify-content:center;gap:2px;padding:6px 26px;min-height:56px;text-decoration:none;color:var(--muted);transition:background .15s,color .15s}
.switch-tabs a+a{border-left:1px solid var(--line-strong)}
.switch-tabs b{font-family:var(--serif);font-size:19px;font-weight:700;letter-spacing:.04em;line-height:1.2}
.switch-tabs span{font-family:var(--mono);font-size:10px;letter-spacing:.12em}
.switch-tabs a:hover{background:var(--paper-2);color:var(--ink)}
.switch-tabs a[aria-current]{background:var(--ink);color:var(--paper)}
.switch-tabs a[aria-current] span{color:var(--accent-soft)}
header nav{flex:none}

/* 地図の前の一行 */
.lede{margin:0;padding:18px 0 14px;font-size:15px;color:var(--muted)}
.lede b{color:var(--ink);font-weight:600}

/* 右の欄: 表示の設定はたたむ */
details.settings{margin-top:20px;border-top:1px solid var(--line);padding-top:6px}
details.settings summary,details.doc summary{cursor:pointer;list-style:none;display:flex;align-items:center;gap:10px;min-height:44px;font-size:13px;color:var(--muted)}
details.settings summary::-webkit-details-marker,details.doc summary::-webkit-details-marker{display:none}
details.settings summary::before,details.doc summary::before{content:"+";font-family:var(--mono);width:18px;height:18px;border:1px solid var(--line-strong);border-radius:3px;display:grid;place-items:center;flex:none;line-height:1}
details[open].settings summary::before,details[open].doc summary::before{content:"−"}
details.settings summary:hover,details.doc summary:hover{color:var(--ink)}
details.settings .copy{width:100%;margin-top:10px;font-size:13px}

/* 先生へ: GitHub の練習 */
.teach{margin-top:48px;padding-top:32px;border-top:1px solid var(--line);max-width:820px}
.teach h2{font-size:22px;line-height:1.5}
.teach>p{margin:8px 0 0;font-size:14px;color:var(--muted);line-height:1.9}
.teach ol{list-style:none;counter-reset:step;margin:22px 0 0;padding:0}
.teach li{counter-increment:step;display:grid;grid-template-columns:44px 1fr;column-gap:14px;padding:12px 0;border-bottom:1px solid var(--line)}
.teach li::before{content:counter(step);grid-row:span 2;width:36px;height:36px;border-radius:50%;border:1px solid var(--ink);display:grid;place-items:center;font-family:var(--mono);font-size:14px}
.teach li a{font-family:var(--serif);font-size:18px;font-weight:600;color:var(--ink);text-decoration-color:var(--accent);text-underline-offset:4px;align-self:end}
.teach li a:hover{color:var(--accent)}
.teach li span{font-size:13px;color:var(--muted);line-height:1.8}
.teach-more{margin:14px 0 0;font-size:13px}
.teach-more a{color:var(--muted)}

/* しくみ（たたむ） */
details.doc{margin-top:28px;max-width:820px}
details.doc ul{margin:4px 0 0;padding-left:22px}
details.doc li{font-size:13px;line-height:1.9;color:var(--muted);margin-bottom:4px}
details.doc li b{color:var(--ink)}
.doc-more{font-size:13px;margin:8px 0 0}
.doc-more a{color:var(--muted)}

@media(max-width:760px){
  header{grid-template-columns:1fr auto auto}
  .switch-tabs{grid-column:1/-1;grid-row:2;width:100%;margin:4px 0 0}
  .switch-tabs a{flex:1;padding:6px 10px;min-height:52px;align-items:center}
  .switch-tabs b{font-size:16px}
  .switch-tabs span{font-size:9px}
  header nav{grid-column:2;grid-row:1}
  .theme-toggle{grid-column:3;grid-row:1}
  .lede{font-size:13px;padding:12px 0 10px}
  .teach h2{font-size:18px}
  .teach li a{font-size:16px}
}