:root{
  color-scheme:light;
  --fs-base:clamp(15px,1.05vw + 12px,17px);
  --fs-small:var(--fs-base);
  --page-pad:28px;
  --gap:14px;
  --bd:1px solid rgba(127,127,127,.35);
  --builder-ink:#17241c;
  --builder-green:#176b43;
  --builder-green-dark:#0d4c2f;
  --builder-line:#c9d5cc;
  --builder-accent:#e2ad3b;
  --soft-green:#e4efe8;
  --blue:#174a8b;
  --red:#8f2f2f;
  --tour:#687178;
  --mono:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,"Liberation Mono","Courier New",monospace;
}
*{box-sizing:border-box}
html,body{margin:0;min-height:100%;background:#fff;color:#000}
body{font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif;font-size:var(--fs-base);line-height:1.35}
button,textarea{font:inherit}
button{
  appearance:none;border:1px solid var(--builder-green-dark);background:var(--builder-green);color:#fff;
  border-radius:6px;padding:10px 14px;line-height:1.15;font-weight:650;cursor:pointer;
  transition:background .12s ease,box-shadow .12s ease,transform .08s ease
}
button:hover{background:var(--builder-green-dark);box-shadow:0 1px 3px rgba(0,0,0,.18)}
button:active{transform:translateY(1px)}
button:disabled{opacity:.42;cursor:default;transform:none;box-shadow:none}
button.secondary{background:var(--soft-green);border-color:#a9c2b1;color:var(--builder-green-dark)}
button.secondary:hover{background:#d7e8dc}
button.danger{background:var(--red);border-color:#742424}
button.danger:hover{background:#742424}
button.compact{padding:7px 10px;font-size:.88rem}
.app{min-height:100vh;display:flex;flex-direction:column;gap:var(--gap)}
.heroCard{
  margin:0;border-radius:0 0 14px 14px;padding:17px 28px 18px;
  background:linear-gradient(135deg,var(--builder-green-dark),var(--builder-green));
  border-bottom:4px solid var(--builder-accent);box-shadow:0 2px 8px rgba(0,0,0,.16);color:#fff
}
.heroCard{position:relative}
.tipJarButton{
  position:absolute;left:28px;top:14px;z-index:1;display:inline-block;padding:7px 11px;
  border:1px solid #c8fff1;border-radius:6px;background:#7fffd4;
  color:#12382d;text-decoration:none;font-size:.84rem;font-weight:750;line-height:1.15;
  box-shadow:0 1px 3px rgba(0,0,0,.18)
}
.tipJarButton:hover{background:#a7ffe2;border-color:#e2fff6}
.toolVersion{
  position:absolute;right:28px;top:18px;color:rgba(255,255,255,.9);
  font-size:.82rem;font-weight:600;letter-spacing:.02em;white-space:nowrap
}
.heroTop{text-align:center}
.heroTitle{margin:0;color:#fff;font-size:clamp(1.8rem,4vw,2.35rem);line-height:1.08}
.heroText{max-width:850px;margin:9px auto 0;color:#dcebe2;line-height:1.45}
.main{
  flex:1;display:grid;grid-template-columns:minmax(250px,330px) minmax(0,1fr);gap:var(--gap);
  padding:0 var(--page-pad) 24px;min-width:0
}
.left,.right{min-width:0}
.right{display:flex;flex-direction:column;gap:var(--gap)}
.card{border:var(--bd);border-radius:12px;padding:14px;background:#fff;min-width:0}
.lessonsCard{position:sticky;top:12px;max-height:calc(100vh - 36px);overflow:auto}
h2,h3{margin:0;color:var(--builder-ink)}
.sectionHeadingRow,.lessonTitleRow{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap}
.lessonTitleRow{align-items:flex-start}
.headerActions{display:flex;gap:9px;flex-wrap:wrap}
.tourButton{background:var(--tour);border-color:#565e64}
.tourButton:hover{background:#565e64}
.muted{opacity:.72}.small{font-size:.9rem}
.eyebrow{font-size:.78rem;font-weight:800;letter-spacing:.08em;text-transform:uppercase;color:var(--builder-green);margin-bottom:3px}
.lessonSummary{margin:12px 0 0;max-width:95ch}
.goals{display:flex;gap:7px;flex-wrap:wrap;margin-top:12px}
.goalChip{background:#eef5f0;border:1px solid #c7d8cd;color:#234732;border-radius:999px;padding:5px 9px;font-size:.84rem}
.lessonList{display:flex;flex-direction:column;gap:7px;margin-top:12px}
.lessonItem{
  width:100%;display:grid;grid-template-columns:28px minmax(0,1fr) auto;align-items:center;gap:8px;
  text-align:left;background:#fff;color:var(--builder-ink);border:1px solid #cfd9d2;border-radius:8px;padding:9px 10px;font-weight:600
}
.lessonItem:hover{background:#f1f7f3}
.lessonItem.active{background:#e4efe8;border-color:#7eaa8d;box-shadow:inset 4px 0 0 var(--builder-green)}
.lessonItem .num{
  width:25px;height:25px;border-radius:50%;display:grid;place-items:center;background:#eef2ef;color:#355341;font-size:.78rem
}
.lessonItem .done{color:var(--builder-green);font-weight:900;min-width:18px;text-align:center}
.workGrid{display:grid;grid-template-columns:minmax(360px,.9fr) minmax(420px,1.1fr);gap:var(--gap);min-height:440px}
.editorCard,.notationCard{min-height:440px;display:flex;flex-direction:column}
#abcEditor{
  width:100%;flex:1;min-height:330px;resize:vertical;margin-top:11px;border:var(--bd);border-radius:9px;
  padding:12px;font-family:var(--mono);font-size:14px;line-height:1.45;background:#fff;color:#000;tab-size:2
}
#abcEditor:focus{outline:2px solid rgba(23,107,67,.35);border-color:#7aaa8b}
.status{min-height:1.4em;margin-top:8px;font-size:.86rem;color:#4a5a50}
.status.error{color:#8a2525}
.paper{flex:1;overflow:auto;margin-top:8px;padding:4px;background:#fff}
.paper svg{max-width:100%;height:auto}
.audio{margin-top:8px;min-height:42px}
.audio .abcjs-inline-audio{max-width:100%}
.notesCard{padding-bottom:12px}
.lessonNotes{margin-top:10px;max-width:100ch}
.lessonNotes p{margin:0 0 10px}
.lessonNotes code,.tour-card code{font-family:var(--mono);background:rgba(127,127,127,.14);padding:2px 5px;border-radius:4px}
.lessonNotes .exampleLine{font-family:var(--mono);white-space:pre-wrap;background:#f6f8f6;border-left:4px solid #abc4b3;padding:8px 10px;margin:8px 0 12px}
.lessonNav{display:flex;justify-content:space-between;gap:10px;margin-top:14px;padding-top:12px;border-top:1px solid #d9dfdb}

/* Guided-tour UI, intentionally based on the Chord Chart Generator tour. */
.tour-overlay{position:fixed;inset:0;background:rgba(0,0,0,.18);z-index:2500;pointer-events:auto}
.tour-card{
  position:fixed;z-index:2147483646;width:min(500px,calc(100vw - 24px));max-width:calc(100vw - 24px);
  max-height:calc(100vh - 24px);overflow-y:auto;overscroll-behavior:contain;background:#f5ffff;
  border:1px solid #bfcfcf;border-radius:5px;box-shadow:0 10px 26px rgba(0,0,0,.25);padding:24px;
  font-family:Helvetica,Arial,sans-serif
}
.tour-card h2{margin:0 0 10px;color:#000;font-size:1.4em;text-align:left}
.tour-card p{margin:0 0 10px;color:#000;font-size:12pt;line-height:18pt}
.tour-footer{margin-top:14px;padding-top:12px;border-top:1px solid #d8e3e3}
.tour-count{text-align:center;color:#333;font-size:.92em;margin-bottom:10px}
.tour-buttons{display:flex;justify-content:center;gap:10px;flex-wrap:wrap}
.tour-buttons button{min-width:94px;padding:7px 15px;color:#000;background:#e5e5e5;border:1px solid #aaa;font:11pt Helvetica,Arial,sans-serif}
.tour-buttons button:hover{background:#d5d5d5}
.tour-highlight{
  position:relative;z-index:2147483644!important;
  box-shadow:0 0 0 4px rgba(0,90,173,.30),0 0 0 9999px rgba(255,255,255,.06)!important;border-radius:8px
}
.tour-arrow-layer{position:fixed;inset:0;width:100vw;height:100vh;z-index:2147483645;pointer-events:none;overflow:visible}
.tour-arrow-path{stroke:#d32f2f;stroke-width:3;fill:none;stroke-linecap:round;stroke-linejoin:round;filter:drop-shadow(0 1px 2px rgba(0,0,0,.2))}
@media(max-width:1000px){
  .main{grid-template-columns:1fr;padding:0 16px 20px}
  .lessonsCard{position:relative;top:auto;max-height:none}
  .lessonList{display:grid;grid-template-columns:repeat(2,minmax(0,1fr))}
  .workGrid{grid-template-columns:1fr}
}
@media(max-width:620px){
  .heroCard{padding:14px 14px 15px}
  .tipJarButton{left:10px;top:9px;padding:6px 9px;font-size:.78rem}
  .toolVersion{right:10px;top:13px;font-size:.76rem}
  .heroTop{padding-top:24px}
  .heroTitle{font-size:1.45rem}
  .heroText{font-size:.9rem}
  .main{padding:0 10px 16px}
  .lessonList{grid-template-columns:1fr}
  .headerActions{width:100%}.headerActions button{flex:1}
  .sectionHeadingRow{align-items:flex-start}
  .workGrid{display:block}.notationCard{margin-top:var(--gap)}
  .lessonNav button{flex:1}
}

#paper .tutor-playing{fill:#d32f2f!important;stroke:#d32f2f!important;color:#d32f2f!important}


/* Laptop-first desktop optimization.
   Keeps the full two-column workspace on typical 1366x768 through 1440x900
   screens while reducing vertical chrome and giving notation more room. */
@media (min-width:1001px) and (max-height:950px){
  :root{
    --page-pad:18px;
    --gap:10px;
  }

  .app{gap:10px}

  .heroCard{
    padding:10px 22px 11px;
    border-bottom-width:3px;
    border-radius:0 0 10px 10px;
  }
  .tipJarButton{left:18px;top:8px;padding:6px 10px;font-size:.8rem}
  .toolVersion{right:18px;top:12px;font-size:.78rem}
  .heroTitle{font-size:1.72rem}
  .heroText{
    margin-top:4px;
    line-height:1.25;
    font-size:.92rem;
  }

  .main{
    grid-template-columns:minmax(240px,285px) minmax(0,1fr);
    gap:10px;
    padding:0 var(--page-pad) 14px;
  }

  .right{gap:10px}
  .card{padding:10px 12px;border-radius:9px}

  .lessonsCard{
    top:8px;
    max-height:calc(100vh - 16px);
  }
  .lessonsCard .sectionHeadingRow{gap:8px}
  .lessonList{gap:4px;margin-top:8px}
  .lessonItem{
    grid-template-columns:24px minmax(0,1fr) auto;
    gap:7px;
    padding:6px 8px;
    border-radius:7px;
    line-height:1.18;
    font-size:.91rem;
  }
  .lessonItem .num{
    width:22px;
    height:22px;
    font-size:.72rem;
  }
  button.compact{padding:5px 8px;font-size:.8rem}

  .lessonTitleRow{gap:8px}
  .headerActions{gap:6px}
  .headerActions button{padding:7px 10px}
  .eyebrow{margin-bottom:1px}
  .lessonSummary{margin:6px 0 0;line-height:1.28}
  .goals{gap:5px;margin-top:7px}
  .goalChip{padding:3px 7px;font-size:.78rem}

  .notesCard{padding:9px 12px}
  .lessonNotes{
    display:grid;
    grid-template-columns:repeat(2,minmax(0,1fr));
    gap:8px 16px;
    margin-top:6px;
    max-width:none;
    line-height:1.28;
  }
  .lessonNotes p{margin:0}
  .lessonNav{
    margin-top:8px;
    padding-top:8px;
  }
  .lessonNav button{padding:7px 11px}

  .workGrid{
    grid-template-columns:minmax(350px,.88fr) minmax(460px,1.12fr);
    gap:10px;
    min-height:clamp(360px,calc(100vh - 365px),540px);
  }
  .editorCard,.notationCard{
    min-height:clamp(360px,calc(100vh - 365px),540px);
  }
  #abcEditor{
    min-height:260px;
    margin-top:7px;
    padding:9px 10px;
    font-size:13px;
    line-height:1.38;
  }
  .status{margin-top:5px;font-size:.8rem}
  .paper{margin-top:4px;padding:2px}
  .audio{margin-top:5px;min-height:38px}
}

/* Slightly wider laptops benefit from a little more notation width. */
@media (min-width:1280px) and (max-height:950px){
  .main{grid-template-columns:minmax(240px,270px) minmax(0,1fr)}
  .workGrid{grid-template-columns:minmax(360px,.84fr) minmax(500px,1.16fr)}
}

/* Short laptop displays need one more compact step. */
@media (min-width:1001px) and (max-height:760px){
  .heroCard{padding:7px 20px 8px}
  .heroTitle{font-size:1.55rem}
  .heroText{font-size:.86rem;margin-top:2px}
  .lessonSummary{font-size:.92rem}
  .notesCard{padding-top:7px;padding-bottom:7px}
  .lessonNotes{font-size:.9rem}
  .workGrid,.editorCard,.notationCard{
    min-height:340px;
  }
  #abcEditor{min-height:235px}
}


/* First-run introduction dialog. */
.welcomeOverlay{
  position:fixed;inset:0;z-index:2147483647;display:flex;align-items:flex-start;justify-content:center;
  padding:150px 18px 18px;background:rgba(0,0,0,.34)
}
.welcomeDialog{
  width:min(620px,100%);max-height:calc(100vh - 36px);overflow:auto;background:#fff;color:#000;
  border:1px solid #b9c8be;border-radius:10px;box-shadow:0 14px 36px rgba(0,0,0,.28);padding:24px
}
.welcomeDialog h2{margin:0 0 14px;color:var(--builder-ink);font-size:1.45rem}
.welcomeDialog p{margin:0 0 12px;line-height:1.45}
.welcomeActions{display:flex;justify-content:center;margin-top:20px;padding-top:16px;border-top:1px solid #d9dfdb}
.welcomeActions button{min-width:150px}
@media(max-width:620px){
  .welcomeOverlay{padding:50px 10px 10px}
  .welcomeDialog{padding:18px;max-height:calc(100vh - 20px)}
}

/* Per-lesson quiz dialog. */
.quizButton{background:#315f8c;border-color:#274d72}
.quizButton:hover{background:#274d72}
.quizOverlay{
  position:fixed;inset:0;z-index:2147483647;display:flex;align-items:flex-start;justify-content:center;
  padding:110px 18px 18px;background:rgba(0,0,0,.34);overflow:auto
}
.quizDialog{
  width:min(660px,100%);max-height:calc(100vh - 128px);overflow:auto;background:#fff;color:#000;
  border:1px solid #b9c8be;border-radius:10px;box-shadow:0 14px 36px rgba(0,0,0,.28);padding:22px
}
.quizHeader{display:flex;align-items:flex-start;justify-content:space-between;gap:16px}
.quizHeader h2{margin:2px 0 0;font-size:1.35rem}
.quizEyebrow{font-size:.75rem;font-weight:800;letter-spacing:.08em;text-transform:uppercase;color:var(--builder-green)}
.quizClose{background:transparent!important;color:#333!important;border:0!important;font-size:1.75rem!important;line-height:1!important;padding:0 4px!important;min-width:34px;box-shadow:none!important}
.quizProgress{margin-top:18px;color:#526158;font-size:.88rem;font-weight:700}
.quizQuestion{margin-top:8px;font-size:1.08rem;font-weight:700;line-height:1.4}
.quizOptions{border:0;padding:0;margin:16px 0 0;display:grid;gap:9px}
.quizOption{display:flex;align-items:flex-start;gap:10px;padding:11px 12px;border:1px solid #cfd9d2;border-radius:8px;background:#fff;cursor:pointer;line-height:1.35}
.quizOption:hover{background:#f3f7f4}
.quizOption input{margin-top:3px;flex:0 0 auto}
.quizOption.correct{background:#eaf5ed;border-color:#76a783}
.quizOption.incorrect{background:#fbecec;border-color:#c88989}
.quizFeedback{min-height:1.5em;margin-top:14px;padding:0;line-height:1.4}
.quizFeedback.correct,.quizFeedback.incorrect{padding:10px 12px;border-radius:8px}
.quizFeedback.correct{background:#eaf5ed;border:1px solid #b7d2bf}
.quizFeedback.incorrect{background:#fff3e5;border:1px solid #e0c39d}
.quizActions{display:flex;justify-content:flex-end;gap:10px;flex-wrap:wrap;margin-top:18px;padding-top:14px;border-top:1px solid #d9dfdb}
.quizResult{text-align:center;padding:26px 8px 8px}
.quizScore{font-size:2rem;font-weight:800;color:var(--builder-green-dark)}
.quizResult p{margin:8px 0 0}
.srOnly{position:absolute!important;width:1px!important;height:1px!important;padding:0!important;margin:-1px!important;overflow:hidden!important;clip:rect(0,0,0,0)!important;white-space:nowrap!important;border:0!important}
@media(max-width:620px){
  .quizOverlay{padding:50px 10px 10px}
  .quizDialog{padding:17px;max-height:calc(100vh - 60px)}
  .quizActions button{flex:1 1 130px}
}


/* ABC Transcription Tools handoff button. */
.abcToolsButton{white-space:nowrap}
@media(max-width:620px){
  .notationCard .sectionHeadingRow{align-items:center}
  .abcToolsButton{white-space:normal;text-align:center}
}