/* L-4 engineering rabbit hole — motor, ESC and propeller sizing */
.prop-sizing-page{background:#f4efdf;color:#171a16}
.prop-sizing-page .l4-hero{min-height:86vh}
.prop-sizing-page .l4-hero-inner{width:min(1180px,92%)}
.prop-sizing-page .l4-hero-media img{object-position:center 58%;filter:saturate(.72) brightness(.78) contrast(1.08)}
.prop-sizing-page .l4-hero::before{background:linear-gradient(90deg,rgba(8,12,9,.96) 0%,rgba(8,12,9,.84) 46%,rgba(8,12,9,.28) 79%),linear-gradient(0deg,rgba(8,12,9,.96) 0%,transparent 58%)}
.prop-sizing-page .l4-hero::after{display:none}
.prop-sizing-page .l4-hero h1{max-width:920px;font-size:clamp(3.1rem,7vw,6.75rem);line-height:.91;color:#f7f2e4;text-shadow:0 3px 18px rgba(0,0,0,.72)}
.prop-sizing-page .l4-hero .l4-deck{max-width:820px}
.prop-sizing-page .l4-status-plate{align-self:end}
.rabbit-hole-marker{display:flex;align-items:center;gap:.8rem;margin:0 0 .8rem}
.rabbit-hole-marker img{display:block;width:62px;height:62px;object-fit:contain;filter:drop-shadow(0 3px 8px rgba(0,0,0,.38))}
.rabbit-hole-marker .l4-kicker{margin:0}

.engineering-sequence{display:grid;grid-template-columns:repeat(8,minmax(0,1fr));gap:0;margin:2rem 0 0;border:1px solid rgba(255,255,255,.23);background:#111811}
.engineering-sequence span{position:relative;display:flex;align-items:center;justify-content:center;min-height:76px;padding:.8rem .45rem;color:#f7f2e4;font-size:.72rem;font-weight:900;letter-spacing:.08em;text-align:center;text-transform:uppercase;border-right:1px solid rgba(255,255,255,.16)}
.engineering-sequence span:last-child{border-right:0}
.engineering-sequence span:not(:last-child)::after{content:"→";position:absolute;right:-.5rem;z-index:2;color:#f2c14e;background:#111811;padding:.12rem}

.rabbit-intro{padding:clamp(3.5rem,7vw,6.5rem) 0;background:#171d17;color:#f4efdf}
.rabbit-intro-grid{display:grid;grid-template-columns:minmax(0,1.18fr) minmax(300px,.82fr);gap:clamp(2rem,5vw,5rem);align-items:center}
.rabbit-intro h2,.engineering-copy h2{font-size:clamp(2.35rem,5.4vw,5rem);line-height:.96;letter-spacing:-.045em;margin:.25rem 0 1.25rem;text-wrap:balance}
.rabbit-intro p,.engineering-copy p{font-size:1.08rem;line-height:1.75}
.rabbit-question{margin:1.5rem 0;padding:1.35rem 1.4rem;border-left:5px solid #f2c14e;background:#253025;font-family:Georgia,"Times New Roman",serif;font-size:clamp(1.45rem,3vw,2.25rem);line-height:1.25;color:#fff}
.rabbit-photo{margin:0;background:#0f130f;border:1px solid rgba(255,255,255,.2)}
.rabbit-photo img{display:block;width:100%;height:auto;aspect-ratio:4/3;object-fit:cover}
.rabbit-photo figcaption{padding:1rem 1.1rem;color:#e6eadf;line-height:1.45}
.rabbit-photo figcaption span{display:block;color:#f2c14e;font-size:.74rem;font-weight:850;letter-spacing:.09em;text-transform:uppercase;margin-top:.35rem}

.engineering-section{padding:clamp(4.2rem,8vw,7.5rem) 0}
.engineering-section.light{background:#f4efdf;color:#171a16}
.engineering-section.dark{background:#171d17;color:#f4efdf}
.engineering-section.olive{background:#374232;color:#fff}
.engineering-wrap{width:min(1120px,92%);margin:0 auto}
.engineering-copy{max-width:860px}
.engineering-copy.wide{max-width:none}
.engineering-copy h3{font-size:clamp(1.65rem,3vw,2.5rem);line-height:1.08;margin:2.5rem 0 .75rem}
.engineering-kicker{margin:0;color:#b87327;font-size:.76rem;font-weight:900;letter-spacing:.16em;text-transform:uppercase}
.dark .engineering-kicker,.olive .engineering-kicker{color:#f2c14e}
.engineering-lede{font-size:clamp(1.25rem,2.3vw,1.65rem)!important;line-height:1.55!important}
.engineering-divider{width:76px;height:3px;margin:2.25rem 0;background:#c27a24}

.key-metrics{display:grid;grid-template-columns:repeat(4,1fr);gap:1rem;margin:2rem 0 0}
.key-metric{padding:1.35rem 1.2rem;border-top:4px solid #f2c14e;background:#101510;color:#f4efdf}
.key-metric strong{display:block;font-family:Georgia,"Times New Roman",serif;font-size:clamp(1.65rem,3vw,2.65rem);line-height:1;color:#f2c14e}
.key-metric span{display:block;margin-top:.65rem;font-size:.76rem;font-weight:850;letter-spacing:.08em;line-height:1.35;text-transform:uppercase;color:#dfe5db}

.clearance-grid{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(300px,.9fr);gap:clamp(2rem,5vw,4.5rem);align-items:center}
.clearance-figure{margin:0;padding:clamp(1.4rem,4vw,2.5rem);background:#142019;color:#fff;border:1px solid #4d5d50}
.clearance-primary{padding-bottom:1.4rem;border-bottom:1px solid rgba(255,255,255,.2)}
.clearance-primary strong{display:block;font-family:Georgia,"Times New Roman",serif;font-size:clamp(4rem,10vw,7.5rem);line-height:.82;color:#f2c14e}
.clearance-primary span{display:block;margin-top:1rem;font-weight:900;letter-spacing:.12em;text-transform:uppercase}
.clearance-math{display:grid;gap:.7rem;margin-top:1.4rem}
.clearance-math div{display:flex;justify-content:space-between;gap:1rem;padding-bottom:.7rem;border-bottom:1px solid rgba(255,255,255,.12)}
.clearance-math span{color:#c9d1c6}
.clearance-math b{color:#fff;text-align:right}
.source-note{margin-top:1.25rem;padding:1rem 1.1rem;background:#fff8e8;border-left:5px solid #c27a24;color:#302919;font-size:.95rem;line-height:1.6}

.engineering-table-wrap{overflow-x:auto;margin:1.75rem 0 2rem;border:1px solid #cfc5af;background:#fffaf0}
.engineering-table{width:100%;border-collapse:collapse;min-width:620px}
.engineering-table th,.engineering-table td{padding:1rem 1.1rem;text-align:left;border-bottom:1px solid #d8cfbc;vertical-align:top}
.engineering-table th{background:#152018;color:#f2c14e;font-size:.76rem;letter-spacing:.1em;text-transform:uppercase}
.engineering-table tbody tr:last-child td{border-bottom:0}
.engineering-table td:first-child{font-weight:900;color:#784a16}
.dark .engineering-table-wrap,.olive .engineering-table-wrap{border-color:#536052}
.dark .engineering-table,.olive .engineering-table{background:#202a20;color:#fff}
.dark .engineering-table td,.olive .engineering-table td{border-color:#465045}
.dark .engineering-table td:first-child,.olive .engineering-table td:first-child{color:#f2c14e}

.voltage-bars{display:grid;grid-template-columns:repeat(4,1fr);gap:.75rem;margin:2rem 0}
.voltage-bar{display:flex;flex-direction:column;justify-content:flex-end;min-height:250px;padding:1rem;background:#fdf8eb;border:1px solid #d5cbb5;color:#171a16}
.voltage-bar i{display:block;width:100%;background:#a7591d;margin-bottom:1rem}
.voltage-bar:nth-child(1) i{height:145px}.voltage-bar:nth-child(2) i{height:108px}.voltage-bar:nth-child(3) i{height:86px}.voltage-bar:nth-child(4) i{height:72px;background:#476444}
.voltage-bar strong{font-family:Georgia,"Times New Roman",serif;font-size:2rem;line-height:1}
.voltage-bar b{font-size:1.18rem;color:#7b4e18;margin-top:.35rem}
.voltage-bar span{font-size:.75rem;margin-top:.25rem;color:#565a53}

.tuning-line{display:flex;flex-wrap:wrap;align-items:center;gap:.6rem;margin:1.4rem 0 2rem;padding:1.1rem 1.2rem;background:#101510;color:#fff;border-left:5px solid #f2c14e}
.tuning-line span{font-weight:900;letter-spacing:.06em;text-transform:uppercase}
.tuning-line b{color:#f2c14e}

.esc-grid{display:grid;grid-template-columns:minmax(0,1.05fr) minmax(300px,.95fr);gap:clamp(2rem,5vw,4.5rem);align-items:start}
.esc-photo{margin:0;background:#0c100c;border:1px solid rgba(255,255,255,.2)}
.esc-photo img{display:block;width:100%;height:clamp(320px,40vw,520px);object-fit:cover;object-position:center 42%}
.esc-photo figcaption{padding:1rem 1.1rem;color:#e3e7df;line-height:1.5}
.esc-photo strong{display:block;color:#f2c14e;margin-bottom:.35rem}
.candidate-label{display:inline-block;margin-bottom:.9rem;padding:.45rem .65rem;border:1px solid #f2c14e;color:#f2c14e;font-size:.72rem;font-weight:900;letter-spacing:.1em;text-transform:uppercase}

.design-envelope{display:grid;grid-template-columns:repeat(2,1fr);gap:0;margin-top:2rem;border:1px solid rgba(255,255,255,.2)}
.design-envelope div{display:grid;grid-template-columns:minmax(145px,.65fr) 1fr;gap:1rem;padding:1rem 1.1rem;border-bottom:1px solid rgba(255,255,255,.15)}
.design-envelope div:nth-child(odd){border-right:1px solid rgba(255,255,255,.15)}
.design-envelope div:nth-last-child(-n+2){border-bottom:0}
.design-envelope dt{font-size:.72rem;font-weight:900;letter-spacing:.08em;text-transform:uppercase;color:#bfc8b5}
.design-envelope dd{margin:0;font-weight:750;color:#fff}

.next-chapter{padding:clamp(2rem,5vw,3.5rem);border:1px solid #596756;background:#101510;color:#fff}
.next-chapter h2{font-size:clamp(2.35rem,5vw,4.6rem);line-height:.95;margin:.35rem 0 1.1rem}
.next-chapter .status{display:inline-block;margin-top:1rem;padding:.45rem .65rem;border:1px solid #f2c14e;color:#f2c14e;font-weight:900;letter-spacing:.1em;text-transform:uppercase;font-size:.72rem}
.next-chapter-list{columns:2;column-gap:2.5rem;margin:1.5rem 0 0;padding-left:1.15rem}
.next-chapter-list li{break-inside:avoid;margin:.45rem 0;color:#dfe5dc}

.propulsion-rabbit-link{padding:clamp(2.5rem,5vw,4rem) 0;background:#111811;color:#fff}
.propulsion-rabbit-link .l4-wrap{width:min(1180px,92%)}
.propulsion-rabbit-link .l4-wrap{display:block}
.propulsion-rabbit-link h2{margin:.3rem 0 .7rem;font-size:clamp(2rem,4vw,3.8rem);line-height:.98}
.propulsion-rabbit-link p{max-width:780px;line-height:1.65;color:#e2e6de}
.propulsion-rabbit-head{margin-bottom:1.25rem}
.propulsion-rabbit-links{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:1rem}
.propulsion-rabbit-card{display:grid;grid-template-columns:62px 1fr;gap:1rem;align-items:start;padding:1.2rem;border:1px solid #66583e;background:linear-gradient(145deg,#171a15,#24291f);color:#f4efdf;text-decoration:none;transition:border-color .18s ease,background .18s ease,transform .18s ease}
.propulsion-rabbit-card:hover{border-color:#f2c14e;background:linear-gradient(145deg,#1d2119,#2c3326);color:#fff;transform:translateY(-2px)}
.propulsion-rabbit-card:focus-visible{outline:3px solid #f2c14e;outline-offset:4px}
.propulsion-rabbit-card img{width:60px;height:60px;object-fit:contain}
.propulsion-rabbit-card small{display:block;color:#f2c14e;font:900 .69rem/1.3 Arial,sans-serif;letter-spacing:.11em;text-transform:uppercase}
.propulsion-rabbit-card strong{display:block;margin:.35rem 0;font:700 clamp(1.35rem,2.6vw,1.9rem)/1.12 Georgia,serif;color:#fff}
.propulsion-rabbit-card span span{display:block;color:#d8dfd5;line-height:1.5}
.propulsion-rabbit-card b{display:block;margin-top:.75rem;color:#f2c14e;font:900 .7rem/1.3 Arial,sans-serif;letter-spacing:.09em;text-transform:uppercase}
.next-rabbit-card{max-width:980px;margin:0 auto;grid-template-columns:72px 1fr}
.next-rabbit-card img{width:70px;height:70px}
.next-rabbit-card strong{font-size:clamp(1.5rem,3vw,2.4rem)}
.next-rabbit-card span span{max-width:850px}

@media(max-width:900px){
  .engineering-sequence{grid-template-columns:repeat(4,1fr)}
  .engineering-sequence span:nth-child(4){border-right:0}.engineering-sequence span:nth-child(4)::after{display:none}
  .engineering-sequence span:nth-child(-n+4){border-bottom:1px solid rgba(255,255,255,.16)}
  .rabbit-intro-grid,.clearance-grid,.esc-grid{grid-template-columns:1fr}
  .key-metrics{grid-template-columns:repeat(2,1fr)}
  .design-envelope{grid-template-columns:1fr}
  .design-envelope div,.design-envelope div:nth-child(odd){border-right:0;border-bottom:1px solid rgba(255,255,255,.15)}
  .design-envelope div:last-child{border-bottom:0}
  .propulsion-rabbit-links{grid-template-columns:1fr}
}
@media(max-width:640px){
  .prop-sizing-page .l4-hero{min-height:auto}
  .prop-sizing-page .l4-hero-inner{padding-top:7rem}
  .rabbit-hole-marker img{width:54px;height:54px}
  .engineering-sequence{grid-template-columns:repeat(2,1fr)}
  .engineering-sequence span{min-height:64px}
  .engineering-sequence span:nth-child(even){border-right:0}
  .engineering-sequence span:nth-child(even)::after{display:none}
  .engineering-sequence span:nth-child(-n+6){border-bottom:1px solid rgba(255,255,255,.16)}
  .key-metrics,.voltage-bars{grid-template-columns:1fr 1fr}
  .voltage-bar{min-height:220px}
  .design-envelope div{grid-template-columns:1fr;gap:.3rem}
  .next-chapter-list{columns:1}
}
@media(max-width:430px){.key-metrics{grid-template-columns:1fr}.voltage-bars{gap:.5rem}.voltage-bar{padding:.8rem}.voltage-bar strong{font-size:1.65rem}}