/* ============================================================
   OAT HEART RATE ZONE CALCULATOR — styles
   Lifted from the /cardio widget so the calculator looks
   identical everywhere. Adds .is-embedded for use inside a
   lesson, which drops the big header and tightens the padding.
   ============================================================ */

.oat-hr-calc {
  --bg:#000; --bg-elevated:#0d0d0d; --ink:#FAF9F5;
  --ink-muted:rgba(250,249,245,.7); --ink-dim:rgba(250,249,245,.4);
  --orange:#ED5600; --blue:#385DFF;
  --hairline:rgba(250,249,245,.10); --row-bg:rgba(250,249,245,.02);
  --z1:#4A8FB8; --z2:#5BB87C; --z3:#E8C547; --z4:#E8782C; --z5:#D63B2A;
}
.oat-hr-calc *{box-sizing:border-box;margin:0;padding:0;border-radius:0}
.oat-hr-calc{
  background:var(--bg); color:var(--ink);
  font-family:'Barlow',sans-serif; -webkit-font-smoothing:antialiased;
  padding:3em 1.5em; max-width:100%; margin:0 auto; line-height:1.4;
}

/* embedded inside a lesson block */
.oat-hr-calc.is-embedded{padding:0;background:transparent}
.oat-hr-calc.is-embedded .header-block{display:none}
.oat-hr-calc.is-embedded .calc-grid{grid-template-columns:1fr;gap:20px;max-width:none}

.oat-hr-calc .header-block{text-align:center;max-width:780px;margin:0 auto 2.5em}
.oat-hr-calc .eyebrow{font-family:'Barlow Condensed',sans-serif;font-size:.85em;font-weight:600;letter-spacing:.28em;text-transform:uppercase;color:var(--orange);margin-bottom:1em}
.oat-hr-calc h2.title{font-family:'Archive','Barlow Condensed',sans-serif;font-weight:400;font-size:2.6em;line-height:.95;letter-spacing:.04em;text-transform:uppercase;margin:0 0 .5em;color:var(--ink)}
.oat-hr-calc h2.title .accent{color:var(--orange)}
.oat-hr-calc .lede{font-size:1em;color:var(--ink);line-height:1.6;margin:0 auto;max-width:660px}
.oat-hr-calc .lede strong{color:var(--orange)}

.oat-hr-calc .calc-grid{display:grid;grid-template-columns:340px 1fr;gap:32px;align-items:start;max-width:1100px;margin:0 auto}
.oat-hr-calc .inputs{background:var(--bg-elevated);border:1px solid var(--hairline);padding:24px}
.oat-hr-calc .input-group{margin-bottom:22px}
.oat-hr-calc .input-label{display:flex;justify-content:space-between;align-items:baseline;font-family:'Barlow Condensed',sans-serif;font-weight:600;font-size:14px;letter-spacing:.22em;text-transform:uppercase;color:var(--ink-muted);margin-bottom:8px}
.oat-hr-calc .input-label .help{font-family:'Barlow',sans-serif;text-transform:none;letter-spacing:normal;font-size:12px;color:var(--ink-dim);cursor:help;border-bottom:1px dotted var(--ink-dim)}
.oat-hr-calc input[type="number"]{width:100%;background:var(--bg);border:1px solid var(--hairline);color:var(--ink);font-family:'JetBrains Mono','Barlow',monospace;font-weight:600;font-size:32px;padding:14px 16px;outline:none;transition:border-color .2s,background .2s;-moz-appearance:textfield}
.oat-hr-calc input[type="number"]::-webkit-outer-spin-button,
.oat-hr-calc input[type="number"]::-webkit-inner-spin-button{-webkit-appearance:none;margin:0}
.oat-hr-calc input[type="number"]:focus{border-color:var(--orange);background:rgba(237,86,0,.04)}
.oat-hr-calc .input-hint{font-size:12px;color:var(--ink-dim);margin-top:6px;letter-spacing:.04em}

.oat-hr-calc .override-section{margin-top:8px;padding-top:22px;border-top:1px solid var(--hairline)}
.oat-hr-calc .override-toggle{display:flex;align-items:center;gap:10px;cursor:pointer;user-select:none;font-size:13px;color:var(--ink-muted);letter-spacing:.08em;text-transform:uppercase;font-weight:500}
.oat-hr-calc .override-toggle input{width:16px;height:16px;accent-color:var(--orange);cursor:pointer}
.oat-hr-calc .override-fields{display:none;margin-top:16px}
.oat-hr-calc .override-fields.show{display:block}

.oat-hr-calc .calc-btn{display:block;width:100%;background:var(--orange);color:var(--ink);border:none;padding:16px 20px;font-family:'Barlow Condensed',sans-serif;font-weight:700;font-size:18px;letter-spacing:.18em;text-transform:uppercase;cursor:pointer;margin-top:8px;transition:background .2s,transform .1s}
.oat-hr-calc .calc-btn:hover{background:#ff6a18}
.oat-hr-calc .calc-btn:active{transform:translateY(1px)}

.oat-hr-calc .results{min-height:100%}
.oat-hr-calc .empty-state{border:1px dashed var(--hairline);padding:48px 28px;text-align:center;color:var(--ink-dim)}
.oat-hr-calc .empty-state-title{font-family:'Barlow Condensed',sans-serif;font-size:22px;font-weight:600;text-transform:uppercase;letter-spacing:.2em;color:var(--ink-muted);margin-bottom:8px}
.oat-hr-calc .empty-state-sub{font-size:15px;line-height:1.5;max-width:360px;margin:0 auto}

.oat-hr-calc .stats-bar{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--hairline);margin-bottom:24px;border:1px solid var(--hairline)}
.oat-hr-calc .stat-cell{background:var(--bg-elevated);padding:18px 22px}
.oat-hr-calc .stat-label{font-size:11px;font-weight:600;letter-spacing:.28em;text-transform:uppercase;color:var(--orange);margin-bottom:4px}
.oat-hr-calc .stat-value{font-family:'Barlow Condensed',sans-serif;font-weight:700;font-size:32px;line-height:1;color:var(--ink)}
.oat-hr-calc .stat-unit{font-size:14px;color:var(--ink-dim);margin-left:6px}
.oat-hr-calc .stat-sub{font-size:11px;color:var(--ink-dim);margin-top:4px;letter-spacing:.1em;text-transform:uppercase}

.oat-hr-calc .zone-row{display:grid;grid-template-columns:56px 1fr auto;gap:20px;align-items:center;padding:18px 20px;border-bottom:1px solid var(--hairline);background:var(--row-bg);border-left:3px solid var(--zone-color)}
.oat-hr-calc .zone-row:last-of-type{border-bottom:none}
.oat-hr-calc .zone-row[data-zone="1"]{--zone-color:var(--z1)}
.oat-hr-calc .zone-row[data-zone="2"]{--zone-color:var(--z2)}
.oat-hr-calc .zone-row[data-zone="3"]{--zone-color:var(--z3)}
.oat-hr-calc .zone-row[data-zone="4"]{--zone-color:var(--z4)}
.oat-hr-calc .zone-row[data-zone="5"]{--zone-color:var(--z5)}
.oat-hr-calc .zone-num{font-family:'Barlow Condensed',sans-serif;font-weight:700;font-size:42px;color:var(--zone-color);line-height:1}
.oat-hr-calc .zone-info-name{font-family:'Barlow Condensed',sans-serif;font-weight:700;font-size:22px;text-transform:uppercase;letter-spacing:.04em;color:var(--ink);margin-bottom:2px}
.oat-hr-calc .zone-info-sub{font-size:13px;color:var(--ink-dim);letter-spacing:.1em;text-transform:uppercase}
.oat-hr-calc .zone-bpm{font-family:'JetBrains Mono','Barlow',monospace;font-weight:600;font-size:24px;color:var(--ink);text-align:right;line-height:1;white-space:nowrap}
.oat-hr-calc .zone-bpm .bpm-unit{font-family:'Barlow',sans-serif;font-size:12px;font-weight:500;letter-spacing:.18em;color:var(--ink-dim);margin-left:4px}
.oat-hr-calc .zone-bpm .pct{display:block;font-size:11px;color:var(--ink-dim);letter-spacing:.18em;margin-top:4px;font-family:'Barlow',sans-serif;font-weight:500;text-transform:uppercase}

.oat-hr-calc .footer-rule{margin-top:28px;height:2px;background:linear-gradient(90deg,var(--orange),var(--blue))}
.oat-hr-calc .footer-note{margin-top:16px;font-size:12px;color:var(--ink-dim);letter-spacing:.1em;text-transform:uppercase;line-height:1.5}
.oat-hr-calc .results-content{opacity:0;transform:translateY(8px);transition:opacity .4s,transform .4s}
.oat-hr-calc .results-content.show{opacity:1;transform:translateY(0)}

@media (max-width:800px){
  .oat-hr-calc{padding:2.4em 1em}
  .oat-hr-calc.is-embedded{padding:0}
  .oat-hr-calc h2.title{font-size:2em}
  .oat-hr-calc .lede{font-size:.95em}
  .oat-hr-calc .calc-grid{grid-template-columns:1fr;gap:24px}
  .oat-hr-calc .inputs{padding:20px}
  .oat-hr-calc input[type="number"]{font-size:26px;padding:12px 14px}
  .oat-hr-calc .stats-bar{grid-template-columns:1fr}
  .oat-hr-calc .zone-row{grid-template-columns:44px 1fr;grid-template-rows:auto auto;gap:8px 14px;padding:14px 16px}
  .oat-hr-calc .zone-num{font-size:32px;grid-row:1 / span 2}
  .oat-hr-calc .zone-info{grid-column:2}
  .oat-hr-calc .zone-info-name{font-size:18px}
  .oat-hr-calc .zone-info-sub{font-size:11px}
  .oat-hr-calc .zone-bpm{grid-column:2;text-align:left;font-size:20px}
  .oat-hr-calc .zone-bpm .pct{display:inline;margin-left:8px;font-size:10px}
  .oat-hr-calc .stat-cell{padding:14px 16px}
  .oat-hr-calc .stat-value{font-size:26px}
}