.mrk-calculator{
  --mrk-green:#8cc63f;
  --mrk-green-dark:#72a92c;
  --mrk-black:#0d0d0d;
  --mrk-charcoal:#242424;
  --mrk-muted:#6b6b6b;
  --mrk-bg:#f4f4f4;
  --mrk-white:#fff;
  font-family:inherit;
  box-sizing:border-box;
  width:100%;
  margin:34px auto;
  color:var(--mrk-black);
}
.mrk-calculator *{box-sizing:border-box}
.mrk-card{
  max-width:1180px;
  margin:0 auto;
  background:linear-gradient(180deg,#f7f7f7 0%,#f2f2f2 100%);
  border-radius:24px;
  padding:48px;
  box-shadow:0 18px 48px rgba(0,0,0,.08);
  border:1px solid rgba(0,0,0,.035);
}
.mrk-head{max-width:900px;margin:0 0 32px}
.mrk-kicker{
  display:inline-flex;
  align-items:center;
  gap:8px;
  color:var(--mrk-green-dark);
  font-size:14px;
  line-height:1;
  font-weight:800;
  text-transform:uppercase;
  letter-spacing:.08em;
  margin:0 0 12px;
}
.mrk-kicker:before{content:"";width:28px;height:4px;border-radius:99px;background:var(--mrk-green)}
.mrk-head h2{
  margin:0 0 10px;
  font-size:clamp(34px,4.3vw,52px);
  line-height:1.02;
  font-weight:900;
  letter-spacing:-.035em;
  color:#000;
}
.mrk-head p{margin:0;color:#616161;font-size:18px;line-height:1.5;font-weight:500}
.mrk-grid{
  display:grid;
  grid-template-columns:repeat(4,minmax(0,1fr));
  gap:18px;
  width:100%;
}
.mrk-item{
  position:relative;
  overflow:hidden;
  min-width:0;
  min-height:166px;
  background:#fff;
  border:1px solid #e7e7e7;
  border-radius:18px;
  padding:28px 20px 22px;
  text-align:center;
  box-shadow:0 10px 28px rgba(0,0,0,.055);
  transition:transform .18s ease,box-shadow .18s ease,border-color .18s ease;
}
.mrk-item-accent{position:absolute;left:0;top:0;width:100%;height:5px;background:var(--mrk-green);opacity:.95}
.mrk-item:hover,.mrk-item:focus-within{transform:translateY(-3px);border-color:rgba(140,198,63,.75);box-shadow:0 14px 32px rgba(0,0,0,.085)}
.mrk-item label{display:block;margin:0 0 18px;font-size:20px;line-height:1.2;font-weight:800;color:#202020}
.mrk-stepper{
  display:grid;
  grid-template-columns:46px minmax(58px,1fr) 46px;
  align-items:center;
  gap:8px;
  max-width:190px;
  margin:0 auto;
}
.mrk-step{
  appearance:none;
  -webkit-appearance:none;
  height:46px;
  border:0;
  border-radius:10px;
  background:#050505;
  color:#fff;
  font:800 25px/1 inherit;
  cursor:pointer;
  transition:background .15s ease,transform .15s ease,box-shadow .15s ease;
}
.mrk-step:hover,.mrk-step:focus-visible{background:var(--mrk-green);outline:none;box-shadow:0 0 0 4px rgba(140,198,63,.2)}
.mrk-step:active{transform:scale(.96)}
.mrk-input{
  width:100%;
  min-width:0;
  height:46px;
  padding:5px 8px;
  border:2px solid #dcdcdc;
  border-radius:10px;
  background:#fff;
  color:#111;
  text-align:center;
  font-size:19px;
  font-weight:900;
  outline:none;
  box-shadow:inset 0 1px 2px rgba(0,0,0,.03);
}
.mrk-input:focus{border-color:var(--mrk-green);box-shadow:0 0 0 4px rgba(140,198,63,.16)}
.mrk-input::-webkit-inner-spin-button,.mrk-input::-webkit-outer-spin-button{-webkit-appearance:none;margin:0}
.mrk-input[type=number]{-moz-appearance:textfield}
.mrk-unit{display:block;margin-top:8px;color:#9a9a9a;font-size:12px;font-weight:700;text-transform:uppercase;letter-spacing:.07em}
.mrk-result{
  margin-top:24px;
  background:var(--mrk-charcoal);
  color:#fff;
  border-radius:18px;
  padding:30px 32px;
  display:grid;
  grid-template-columns:minmax(0,1.25fr) minmax(360px,.75fr);
  gap:28px;
  align-items:center;
  box-shadow:0 14px 34px rgba(0,0,0,.12);
}
.mrk-result-label{display:block;color:var(--mrk-green);font-size:13px;font-weight:900;text-transform:uppercase;letter-spacing:.08em;margin-bottom:8px}
.mrk-size-line{font-size:20px;line-height:1.3;font-weight:700;color:#fff}
.mrk-size-line strong{display:block;margin-top:4px;color:var(--mrk-green);font-size:clamp(38px,5vw,58px);line-height:1;font-weight:900;letter-spacing:-.035em}
.mrk-result-note{margin:12px 0 0;color:#d3d3d3;font-size:14px;line-height:1.45;max-width:620px}
.mrk-result-stats{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}
.mrk-stat{min-width:0;background:#fff;border-radius:14px;padding:17px 16px;color:#222}
.mrk-stat span{display:block;color:#7a7a7a;font-size:12px;font-weight:700;text-transform:uppercase;letter-spacing:.04em;margin-bottom:7px}
.mrk-stat strong{display:block;font-size:20px;line-height:1.15;font-weight:900;color:#202020;overflow-wrap:anywhere}
.mrk-stat-price{border:2px solid var(--mrk-green);padding:15px 14px}
.mrk-stat-price strong{color:#111}
.mrk-stat small{display:block;margin-top:3px;color:#909090;font-size:11px}
@media (max-width:900px){
  .mrk-card{padding:36px 26px}
  .mrk-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .mrk-result{grid-template-columns:1fr}
  .mrk-result-stats{max-width:520px}
}
@media (max-width:560px){
  .mrk-calculator{margin:20px auto}
  .mrk-card{padding:28px 16px;border-radius:18px}
  .mrk-head{margin-bottom:24px}
  .mrk-head h2{font-size:34px}
  .mrk-head p{font-size:16px}
  .mrk-grid{grid-template-columns:1fr;gap:12px}
  .mrk-item{min-height:0;padding:22px 16px 18px}
  .mrk-item label{font-size:18px;margin-bottom:14px}
  .mrk-result{padding:24px 18px;border-radius:15px}
  .mrk-result-stats{grid-template-columns:1fr}
}