:root{
    --bg:#F3FAF6;
    --card:#FFFFFF;
    --ink:#3A4440;
    --sub:#7B8A84;
    --green:#22B287;
    --green-deep:#0F8A66;
    --green-pale:#DDF4EC;
    --coral:#FF8A73;
    --coral-pale:#FFEDE8;
    --money-bg:#FFF3C9;
    --money-ink:#8F6400;
    --karte-bg:#E9F2FF;
    --karte-ink:#3B72C4;
    --line:#E3EEE8;
    --r:22px;
  }
  *{box-sizing:border-box;margin:0;padding:0;-webkit-tap-highlight-color:transparent;}
  html{font-size:16px;}
  body{
    font-family:"Hiragino Maru Gothic ProN","Hiragino Kaku Gothic ProN","Yu Gothic Medium","Yu Gothic",Meiryo,sans-serif;
    background:var(--bg);color:var(--ink);line-height:1.8;
    max-width:560px;margin:0 auto;min-height:100vh;padding-bottom:76px;
  }
  /* ---------- header ---------- */
  header{
    background:linear-gradient(150deg,#2BC494 0%,#17A278 100%);
    color:#fff;padding:22px 20px 18px;border-radius:0 0 28px 28px;
    position:relative;overflow:hidden;
  }
  header::after{
    content:"💬";position:absolute;right:14px;top:10px;font-size:3.4rem;opacity:.18;transform:rotate(8deg);
  }
  h1{font-size:1.4rem;font-weight:800;letter-spacing:.03em;}
  .tagline{font-size:.84rem;opacity:.95;margin-top:4px;}
  .supervise{
    display:inline-block;margin-top:10px;font-size:.72rem;font-weight:700;
    background:rgba(255,255,255,.2);border:1px solid rgba(255,255,255,.5);
    padding:3px 12px;border-radius:99px;
  }
  /* ---------- breadcrumb ---------- */
  .crumb{display:flex;align-items:center;gap:8px;padding:14px 18px 2px;font-size:.8rem;color:var(--sub);flex-wrap:wrap;}
  .crumb button{background:none;border:none;color:var(--green-deep);font-size:.8rem;font-weight:700;cursor:pointer;padding:2px 0;font-family:inherit;}
  .crumb span.sep{opacity:.5;}
  main{padding:10px 16px 0;}
  .lead{font-size:.88rem;color:var(--sub);padding:4px 4px 14px;}
  /* ---------- gacha ---------- */
  .gacha-btn{
    width:100%;border:none;border-radius:var(--r);cursor:pointer;font-family:inherit;
    background:linear-gradient(135deg,#FF9A7E,#FF7E9D);color:#fff;
    font-size:1.02rem;font-weight:800;padding:16px;letter-spacing:.04em;
    box-shadow:0 5px 0 #E06A55;margin-bottom:8px;
    transition:transform .1s ease, box-shadow .1s ease;
  }
  .gacha-btn:active{transform:translateY(4px);box-shadow:0 1px 0 #E06A55;}
  .gacha-note{font-size:.72rem;color:var(--sub);text-align:center;margin-bottom:16px;}
  .gacha-card{
    background:var(--card);border:2px solid var(--coral);border-radius:var(--r);
    padding:16px;margin-bottom:16px;animation:pop .3s ease;
  }
  .gacha-card .from{font-size:.74rem;font-weight:700;color:var(--coral);margin-bottom:6px;}
  .gacha-card .jump{
    display:inline-block;margin-top:10px;background:var(--coral-pale);color:#D4553C;
    border:none;border-radius:99px;padding:6px 16px;font-size:.8rem;font-weight:700;
    cursor:pointer;font-family:inherit;
  }
  @keyframes pop{0%{transform:scale(.92);opacity:0;}60%{transform:scale(1.03);}100%{transform:scale(1);opacity:1;}}
  /* ---------- home tiles ---------- */
  .sec-label{font-size:.82rem;font-weight:800;color:var(--green-deep);margin:2px 4px 10px;letter-spacing:.08em;}
  .scene-tile{
    width:100%;text-align:left;background:var(--card);border:2px solid var(--line);
    border-radius:var(--r);padding:16px;margin-bottom:12px;cursor:pointer;
    font-family:inherit;color:var(--ink);display:flex;gap:14px;align-items:center;
    transition:transform .12s ease,border-color .12s ease;
  }
  .scene-tile:active{transform:scale(.97);border-color:var(--green);}
  .scene-tile:focus-visible,button:focus-visible{outline:3px solid var(--green);outline-offset:2px;}
  .scene-ico{
    flex:0 0 52px;height:52px;border-radius:50%;
    display:flex;align-items:center;justify-content:center;font-size:1.6rem;
  }
  .ico1{background:#DDF4EC;} .ico2{background:#FFF0D9;} .ico3{background:#FFE9EC;}
  .ico4{background:#E9F2FF;} .ico5{background:#F2E9FF;}
  .scene-tile h2{font-size:1.02rem;font-weight:800;}
  .scene-tile p{font-size:.79rem;color:var(--sub);margin-top:2px;line-height:1.6;}
  .kasan-chip{display:inline-block;font-size:.68rem;font-weight:700;color:var(--money-ink);background:var(--money-bg);border-radius:8px;padding:1px 9px;margin-top:6px;}
  /* ---------- scene view ---------- */
  .goal{
    background:var(--green-pale);border-radius:var(--r);padding:14px 16px;
    font-size:.86rem;margin-bottom:16px;position:relative;
  }
  .goal .gl{font-weight:800;color:var(--green-deep);font-size:.78rem;letter-spacing:.06em;display:block;margin-bottom:3px;}
  .goal b{color:var(--green-deep);}
  .sit-btn{
    width:100%;text-align:left;background:var(--card);border:2px solid var(--line);
    border-radius:18px;padding:15px 16px;margin-bottom:10px;cursor:pointer;
    font-family:inherit;font-size:.95rem;font-weight:700;color:var(--ink);
    display:flex;justify-content:space-between;align-items:center;gap:10px;
    transition:transform .12s ease,border-color .12s ease;
  }
  .sit-btn:active{transform:scale(.97);border-color:var(--green);}
  .sit-btn .arrow{color:var(--green);font-weight:800;font-size:1.1rem;}
  /* ---------- branch view: chat bubbles ---------- */
  .branch-title{font-size:1.04rem;font-weight:800;margin:4px 2px 4px;}
  .branch-sub{font-size:.78rem;color:var(--sub);margin:0 2px 16px;}
  .bubble-wrap{margin-bottom:18px;}
  .tone-tag{
    display:inline-block;font-size:.74rem;font-weight:800;border-radius:99px;
    padding:2px 12px;margin:0 0 4px 8px;
  }
  .tn1{background:#DDF4EC;color:#0F8A66;} /* 丁寧 */
  .tn2{background:#FFF0D9;color:#B0713A;} /* カジュアル */
  .tn3{background:#FFE9EC;color:#D4557A;} /* ハードル下げ */
  .tn4{background:#F2E9FF;color:#8A5BA6;} /* メリット提示 */
  .tn5{background:#E9F2FF;color:#3B72C4;} /* クッション */
  .bubble{
    position:relative;background:var(--card);border:2px solid var(--line);
    border-radius:20px;border-top-left-radius:6px;padding:13px 15px;
    font-size:.98rem;font-weight:700;line-height:1.8;
  }
  .bubble .copy-btn{
    position:absolute;bottom:-12px;right:12px;border:2px solid var(--line);
    background:#fff;border-radius:99px;font-size:.7rem;font-weight:800;
    color:var(--sub);padding:3px 12px;cursor:pointer;font-family:inherit;
  }
  .bubble .copy-btn.copied{background:var(--green);color:#fff;border-color:var(--green);}
  .why{font-size:.8rem;color:var(--sub);margin:14px 6px 0;}
  .why b{color:var(--green-deep);}
  /* ---------- info boxes ---------- */
  .note-box,.santei-box,.karte-box{border-radius:var(--r);padding:14px 16px;margin-bottom:12px;font-size:.85rem;}
  .note-box{background:#fff;border:2px dashed var(--line);}
  .note-box .bx-t{color:var(--green-deep);}
  .santei-box{background:var(--money-bg);}
  .santei-box .bx-t,.santei-box b{color:var(--money-ink);}
  .karte-box{background:var(--karte-bg);}
  .karte-box .bx-t{color:var(--karte-ink);}
  .bx-t{font-weight:800;font-size:.8rem;display:block;margin-bottom:4px;letter-spacing:.04em;}
  .more-btn{
    display:block;width:100%;text-align:center;background:var(--green);color:#fff;
    border:none;border-radius:99px;padding:14px;font-size:.9rem;font-weight:800;
    font-family:inherit;cursor:pointer;margin:16px 0 6px;box-shadow:0 4px 0 #0E7D5C;
    transition:transform .1s ease, box-shadow .1s ease;
  }
  .more-btn:active{transform:translateY(3px);box-shadow:0 1px 0 #0E7D5C;}
  .more-note{font-size:.72rem;color:var(--sub);text-align:center;margin-bottom:8px;}
  /* ---------- neta chat ---------- */
  .chat{margin-bottom:16px;}
  .chat .row{display:flex;margin-bottom:12px;align-items:flex-end;gap:8px;}
  .chat .row.you{justify-content:flex-end;}
  .chat .face{font-size:1.5rem;flex:0 0 auto;}
  .chat .cb{
    max-width:78%;padding:11px 14px;font-size:.93rem;font-weight:700;line-height:1.7;border-radius:18px;
  }
  .chat .you .cb{background:var(--green);color:#fff;border-bottom-right-radius:5px;}
  .chat .pt .cb{background:#fff;border:2px solid var(--line);border-bottom-left-radius:5px;}
  .chat .heart{
    text-align:center;font-size:.84rem;color:#D4553C;background:var(--coral-pale);
    border-radius:99px;padding:6px 16px;display:table;margin:2px auto 0;
  }
  .neta-point{background:var(--green-pale);border-radius:var(--r);padding:14px 16px;margin-bottom:12px;font-size:.86rem;}
  .neta-point .bx-t{color:var(--green-deep);}
  /* ---------- disclaimer / nav ---------- */
  details.disc{margin:18px 2px 8px;font-size:.78rem;color:var(--sub);background:#fff;border:2px solid var(--line);border-radius:18px;padding:10px 14px;}
  details.disc summary{font-weight:700;cursor:pointer;color:var(--ink);}
  details.disc div{margin-top:8px;line-height:1.8;}
  .back-fab{
    position:fixed;bottom:16px;left:50%;transform:translateX(-50%);
    background:#fff;color:var(--green-deep);border:2px solid var(--green);
    border-radius:99px;padding:11px 30px;font-size:.9rem;font-weight:800;
    font-family:inherit;cursor:pointer;box-shadow:0 4px 12px rgba(20,120,90,.18);
    display:none;letter-spacing:.05em;
  }
  .back-fab.show{display:block;}
  .toast{
    position:fixed;bottom:74px;left:50%;transform:translateX(-50%);
    background:var(--green-deep);color:#fff;font-size:.8rem;font-weight:700;
    padding:8px 20px;border-radius:99px;opacity:0;transition:opacity .25s;pointer-events:none;
  }
  .toast.show{opacity:1;}
  .view{display:none;animation:fade .18s ease;}
  .view.active{display:block;}
  @keyframes fade{from{opacity:0;transform:translateY(5px);}to{opacity:1;transform:none;}}
  @media (prefers-reduced-motion: reduce){*{animation:none!important;transition:none!important;}}
  .followup-box{border-radius:var(--r);padding:14px 16px;margin-bottom:12px;background:#fff;border:2px solid var(--green-pale);font-size:.85rem;}
  .followup-box .bx-t{color:var(--green-deep);}
  .rule-details{margin-top:12px;padding-top:8px;border-top:1px solid #e3d7b1;font-size:.8rem;}
  .rule-details summary{cursor:pointer;font-weight:700;}
  .rule-details p{margin:10px 0;}
  .rule-details a{color:var(--green-deep);}
  .bubble,.goal,.santei-box,.karte-box,.followup-box{overflow-wrap:anywhere;}

  /* 公開用：可読性、タッチ操作、セーフエリア、キーボード移動 */
  :root{--sub:#596c63;--green-deep:#0f7859;--green:#0f7859;--coral:#aa483b;}
  body{padding-bottom:calc(100px + env(safe-area-inset-bottom));}
  header{background:linear-gradient(150deg,#147a5d,#0f6850);padding-top:calc(22px + env(safe-area-inset-top));}
  h1{overflow-wrap:anywhere;}
  button,a,summary{-webkit-tap-highlight-color:rgba(15,120,89,.12);touch-action:manipulation;}
  button{min-height:44px;}
  a:focus-visible,summary:focus-visible{outline:3px solid var(--green-deep);outline-offset:3px;}
  [hidden]{display:none!important;}
  .view{display:block;}
  .sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0;}
  .skip-link{position:fixed;top:-100px;left:12px;z-index:10;background:#fff;color:var(--green-deep);padding:12px;}
  .skip-link:focus{top:12px;}
  .skip-link:not(:focus){clip-path:inset(100%);}
  .crumb button{padding:8px 0;}
  .gacha-btn{background:linear-gradient(135deg,#a94132,#a33760);box-shadow:0 5px 0 #7e2f28;}
  .gacha-btn:active{box-shadow:0 1px 0 #7e2f28;}
  .tile-title{display:block;font-size:1.02rem;font-weight:800;}
  .tile-desc{display:block;font-size:.85rem;color:var(--sub);margin-top:2px;line-height:1.6;}
  .scene-tile>span:last-child{min-width:0;}
  .scene-tile,.sit-btn{overflow-wrap:anywhere;}
  .bubble-wrap{margin-bottom:22px;}
  .bubble{padding-bottom:12px;}
  .bubble .copy-btn{position:static;display:block;margin:10px 0 0 auto;min-width:76px;font-size:.82rem;padding:7px 12px;}
  .why{font-size:.88rem;margin-top:8px;}
  .branch-sub,.note-box,.santei-box,.karte-box,.followup-box,.neta-point,.goal{font-size:.92rem;}
  .tn1{color:#0f7859;} .tn2{color:#78502c;} .tn3{color:#a33760;} .tn4{color:#724588;} .tn5{color:#2a5599;}
  .karte-box .bx-t{color:#2a5599;}
  .gacha-phrase{font-weight:700;margin-top:6px;}
  .gacha-card .jump{color:#9e3b2b;}
  .more-btn{text-decoration:none;}
  .chat .cb{min-width:0;overflow-wrap:anywhere;}
  .chat .heart{border-radius:18px;color:#9e3b2b;overflow-wrap:anywhere;}
  .back-fab{display:block;bottom:calc(16px + env(safe-area-inset-bottom));z-index:2;}
  .toast{bottom:calc(80px + env(safe-area-inset-bottom));max-width:calc(100vw - 32px);width:max-content;border-radius:16px;z-index:4;text-align:center;}
  details.disc{font-size:.85rem;}
  details.disc summary,.rule-details summary{min-height:44px;padding:8px 0;}
  .rule-details{font-size:.85rem;}
  .privacy-note{font-size:.78rem;color:var(--sub);padding:8px 4px;}
  .copy-helper{position:fixed;top:0;left:0;width:1px;height:1px;opacity:0;}
  dialog{border:2px solid var(--line);border-radius:20px;margin:auto;width:min(480px,calc(100% - 32px));max-height:85vh;padding:20px;color:var(--ink);}
  dialog::backdrop{background:rgba(0,0,0,.4);}
  dialog h2{font-size:1.1rem;} dialog p{font-size:.88rem;margin:8px 0;}
  dialog textarea{display:block;width:100%;height:160px;font:inherit;font-size:16px;padding:10px;border:2px solid var(--green-deep);border-radius:10px;resize:vertical;}
  dialog button{display:block;margin:12px 0 0 auto;background:var(--green-deep);color:#fff;border:0;border-radius:99px;padding:8px 24px;font:inherit;}
  @media(max-width:360px){main{padding-left:12px;padding-right:12px;}header{padding-left:16px;padding-right:16px;}.scene-tile{gap:10px;padding:12px;}.scene-ico{flex-basis:44px;height:44px;}.kasan-chip{font-size:.72rem;}}

  /* 書籍のキャラクターといっしょに学ぶ */
  .portrait{display:block;position:relative;flex:0 0 52px;width:52px;height:52px;overflow:hidden;border-radius:50%;background:#fff;border:2px solid #e1eee7;}
  .portrait img{position:absolute;width:145%;max-width:none;height:auto;left:50%;top:-4%;transform:translateX(-50%);}
  .speaker-role{display:block;font-size:.73rem;color:var(--green-deep);font-weight:700;margin-bottom:5px;}
  .welcome-card{display:flex;align-items:center;gap:8px;background:#fff;border:2px solid var(--line);border-radius:24px;padding:18px 14px 18px 18px;margin-bottom:12px;}
  .welcome-copy{flex:1;min-width:0;}
  .welcome-copy h2{font-size:1.17rem;line-height:1.6;color:var(--green-deep);margin-bottom:8px;}
  .welcome-copy p{font-size:.83rem;color:var(--sub);line-height:1.8;}
  .author-illustration{display:block;flex:0 0 126px;width:126px;height:150px;object-fit:contain;}
  .learning-team{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-bottom:20px;}
  .team-member{display:flex;align-items:center;gap:8px;background:#fff;border:1px solid var(--line);border-radius:18px;padding:10px;}
  .team-member>span:last-child{min-width:0;}
  .team-member .portrait{flex-basis:44px;width:44px;height:44px;}
  .team-member small{display:block;color:var(--sub);font-size:.66rem;line-height:1.6;}
  .team-member b{display:block;font-size:.76rem;line-height:1.6;}
  .learner-question{display:flex;align-items:center;gap:12px;margin:0 0 22px;padding:12px 14px;background:#edf4fb;border:1px solid #d6e4ee;border-radius:18px;}
  .learner-question>div{min-width:0;}
  .learner-question .speaker-role{color:#425d7b;font-size:.7rem;margin-bottom:3px;}
  .learner-question p{font-size:.9rem;font-weight:700;line-height:1.8;}
  .mentor-note{display:grid;grid-template-columns:64px minmax(0,1fr);align-items:start;gap:12px;margin:18px 0;}
  .mentor-speaker{display:flex;align-items:center;flex-direction:column;gap:6px;}
  .mentor-speaker .portrait{width:64px;height:64px;flex-basis:64px;border-color:#c9e3d5;}
  .mentor-speaker>span:last-child{font-size:.65rem;text-align:center;line-height:1.5;color:var(--sub);}
  .mentor-speaker b{color:var(--green-deep);font-size:.76rem;}
  .mentor-speech{position:relative;background:#fff;border:2px solid #c9e3d5;border-radius:18px;padding:13px 14px;font-size:.92rem;line-height:1.9;overflow-wrap:anywhere;}
  .mentor-speech::before{content:"";position:absolute;left:-8px;top:23px;width:12px;height:12px;transform:rotate(45deg);background:#fff;border-left:2px solid #c9e3d5;border-bottom:2px solid #c9e3d5;}
  .mentor-speech .bx-t{color:var(--green-deep);font-size:.85rem;}
  @media(max-width:360px){.welcome-card{padding:14px 10px 14px 14px;}.author-illustration{flex-basis:105px;width:105px;height:138px;}.welcome-copy h2{font-size:1.04rem;}.learning-team{gap:7px;}.team-member{padding:8px;gap:6px;}.team-member .portrait{flex-basis:36px;width:36px;height:36px;}.mentor-note{grid-template-columns:52px minmax(0,1fr);gap:10px;}.mentor-speaker .portrait{width:52px;height:52px;flex-basis:52px;}.mentor-speech{padding:12px;}}

  .learn-more{margin:28px 0 20px;padding:18px 16px 14px;border:2px solid #d8e8df;border-radius:24px;background:#fffdf8;}
  .learn-more-intro{display:flex;align-items:center;gap:12px;margin-bottom:16px;}
  .learn-more-intro img{display:block;flex:0 0 76px;width:76px;height:94px;object-fit:contain;background:#fff;border-radius:16px;}
  .learn-more-intro>div{min-width:0;}
  .learn-more-intro .speaker-role{font-size:.69rem;margin-bottom:4px;}
  .learn-more h2{font-size:1.01rem;line-height:1.6;margin-bottom:5px;}
  .learn-more-intro p{font-size:.82rem;color:var(--sub);line-height:1.8;}
  .learn-more-links{display:grid;gap:10px;}
  .learn-link{display:flex;align-items:center;gap:12px;min-height:76px;padding:12px 14px;border:2px solid var(--green-deep);border-radius:16px;text-decoration:none;line-height:1.7;}
  .learn-link-primary{background:var(--green-deep);color:#fff;}
  .learn-link-secondary{background:#fff;color:var(--green-deep);border-color:#d6e6dc;}
  .learn-link>span:nth-child(2){flex:1;min-width:0;}
  .learn-link b{display:block;font-size:.94rem;}
  .learn-link small{display:block;font-size:.75rem;}
  .learn-link-icon{font-size:1.5rem;flex:0 0 30px;text-align:center;}
  .learn-more-caption{text-align:center;color:var(--sub);font-size:.7rem;margin-top:10px;}
  @media(max-width:360px){.learn-more{padding:14px 12px;}.learn-more-intro{gap:10px;}.learn-more-intro img{width:60px;flex-basis:60px;height:80px;}.learn-more h2{font-size:.95rem;}.learn-link{padding:10px 12px;gap:8px;}.learn-link b{font-size:.87rem;}}

  /* シーンを先に選び、解説は必要なところだけ開く */
  #view-home .welcome-card{padding:12px 14px;gap:12px;margin-bottom:16px;}
  #view-home .welcome-title{font-size:.97rem;font-weight:800;color:var(--green-deep);line-height:1.6;margin-bottom:4px;}
  #view-home .author-illustration{flex-basis:72px;width:72px;height:84px;}
  #view-home .scene-tile{gap:10px;padding:11px 12px;margin-bottom:10px;}
  #view-home .scene-ico{flex-basis:40px;height:40px;font-size:1.3rem;}
  #view-home .tile-title{font-size:.97rem;}
  #view-home .tile-desc{font-size:.78rem;}
  .tile-arrow{margin-left:auto;color:var(--green-deep);font-size:1.3rem;flex:0 0 12px;}
  .home-extra-label{margin-top:28px;}
  .phrase-point{margin:9px 3px 0;color:var(--sub);font-size:.86rem;}
  .phrase-point summary{cursor:pointer;min-height:44px;display:list-item;padding:9px 0;color:var(--green-deep);font-weight:700;}
  .phrase-point .why{margin:0 0 8px;padding:4px 8px 4px 12px;border-left:3px solid #c9e3d5;}
  .study-hint{font-size:.78rem;color:var(--sub);margin:6px 3px 14px;}
  .study-details{border:2px solid var(--line);border-radius:18px;background:#fff;margin:0 0 12px;overflow:hidden;}
  .study-details>summary{cursor:pointer;min-height:54px;padding:13px 16px;font-size:.87rem;font-weight:800;}
  .study-body{padding:0 14px 14px;font-size:.92rem;line-height:1.9;overflow-wrap:anywhere;}
  .santei-details{background:var(--money-bg);border-color:#eddea9;}
  .santei-details>summary{color:var(--money-ink);}
  .karte-details{background:var(--karte-bg);border-color:#d0dff3;}
  .karte-details>summary{color:#2a5599;}
  .mentor-details{border-color:#c9e3d5;background:#f0f8f3;}
  .mentor-details>summary{padding:10px 14px;color:var(--green-deep);}
  .mentor-summary{display:inline-flex;align-items:center;gap:10px;vertical-align:middle;}
  .mentor-summary .portrait{width:40px;height:40px;flex-basis:40px;}
  .mentor-summary small{display:block;font-size:.68rem;line-height:1.5;color:var(--sub);font-weight:400;}
  .mentor-summary b{display:block;font-size:.87rem;}
  .mentor-details .study-body{padding-left:20px;}
  .feedback{margin:20px 12px;text-align:center;font-size:.85rem;color:var(--sub);line-height:1.8;}