/* lestnitsa37.ru — «столярная мастерская на чертёжном листе» */
:root{
  --ply:#F1DFC3; --ply2:#EAD3B0; --ply3:#E2C79F; --edge:#C9A473; --card:rgba(255,248,236,.55);
  --ink:#232120; --ink2:#47423D; --mute:#7A6F63; --line:rgba(60,45,30,.18); --grid:rgba(90,70,45,.10);
  --acc:#E8711C; --acc2:#F39A4A; --ok:#3E9B4F; --warn:#E8711C;
  --head:'Geologica',system-ui,sans-serif;
  --text:'Geologica',system-ui,sans-serif;
  --mono:'JetBrains Mono',ui-monospace,Menlo,monospace;
  --w:1220px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;color:var(--ink);font:400 17px/1.55 var(--text);-webkit-font-smoothing:antialiased;background:var(--ply);
  background-image:
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='600' height='600'%3E%3Cfilter id='f'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.004 .09' numOctaves='3' seed='7'/%3E%3CfeColorMatrix values='0 0 0 0 .45 0 0 0 0 .32 0 0 0 0 .18 0 0 0 .16 0'/%3E%3C/filter%3E%3Crect width='600' height='600' filter='url(%23f)'/%3E%3C/svg%3E"),
    linear-gradient(180deg,#F3E3CA,#EEDABB);}
img{max-width:100%;height:auto;display:block}
a{color:inherit}
button,input{font:inherit;color:inherit}
button{cursor:pointer}
.wrap{max-width:var(--w);margin:0 auto;padding:0 32px}
h1,h2,h3{font-family:var(--head);margin:0;letter-spacing:-.02em}
h2{font-size:clamp(30px,3.4vw,44px);line-height:1.08;font-weight:800;text-wrap:balance}
.sub{color:var(--ink2);margin:10px 0 30px;font-size:17px;max-width:720px}
.num{font-family:var(--mono);font-variant-numeric:tabular-nums}

/* стык листов фанеры между блоками */
.sec{position:relative;padding:64px 0 70px}
.sec::before{content:"";position:absolute;left:0;right:0;top:0;height:7px;
  background:linear-gradient(180deg,rgba(120,80,40,.28),rgba(120,80,40,.06) 30%,rgba(255,255,255,.45) 45%,rgba(120,80,40,0) 100%)}

/* ——— шапка и меню ——— */
.top{position:absolute;left:0;right:0;top:0;z-index:20}
.top .wrap{display:flex;justify-content:space-between;align-items:center;padding-top:26px}
.znak{display:flex;align-items:center;gap:12px;text-decoration:none;font:700 21px var(--head);letter-spacing:-.02em}
.znak svg{width:44px;height:30px}
.menu-btn{display:flex;align-items:center;gap:12px;border:0;background:rgba(244,226,196,.92);border-radius:40px;padding:12px 20px 12px 24px;
  font-weight:600;font-size:15px;box-shadow:0 2px 0 rgba(120,80,40,.18),0 8px 22px rgba(80,50,20,.12);transition:transform .2s}
.menu-btn:hover{transform:translateY(-1px)}
.menu-btn i{display:grid;gap:4px}
.menu-btn i b{display:block;width:18px;height:2px;background:var(--ink);border-radius:2px;transition:transform .3s,opacity .3s}
.menu{position:fixed;inset:0;z-index:50;background:var(--ply2);display:grid;grid-template-columns:1.1fr .9fr;
  clip-path:circle(0 at calc(100% - 90px) 50px);transition:clip-path .65s cubic-bezier(.7,0,.2,1);visibility:hidden}
.menu.open{clip-path:circle(150% at calc(100% - 90px) 50px);visibility:visible}
.menu nav{padding:120px 0 60px 9vw;display:flex;flex-direction:column;gap:8px;counter-reset:m}
.menu nav a{display:flex;align-items:baseline;gap:22px;text-decoration:none;font:800 clamp(34px,4.6vw,64px)/1.15 var(--head);letter-spacing:-.03em;
  opacity:0;transform:translateY(24px);transition:opacity .4s,transform .5s,color .2s}
.menu nav a::before{counter-increment:m;content:"0" counter(m);font:500 15px var(--mono);color:var(--mute);width:28px}
.menu nav a:hover{color:var(--acc)}
.menu.open nav a{opacity:1;transform:none}
.menu.open nav a:nth-child(1){transition-delay:.18s}.menu.open nav a:nth-child(2){transition-delay:.24s}
.menu.open nav a:nth-child(3){transition-delay:.30s}.menu.open nav a:nth-child(4){transition-delay:.36s}
.menu.open nav a:nth-child(5){transition-delay:.42s}
.menu aside{border-left:1px solid var(--line);padding:120px 6vw 60px;display:flex;flex-direction:column;justify-content:space-between;
  background-image:linear-gradient(var(--grid) 1px,transparent 1px),linear-gradient(90deg,var(--grid) 1px,transparent 1px);background-size:24px 24px}
.menu aside p{color:var(--ink2);max-width:360px}
.menu aside svg{width:100%;max-width:380px}
.menu-x{position:absolute;right:32px;top:26px}
body.lock{overflow:hidden}

/* ——— первый экран ——— */
.hero{position:relative;height:clamp(560px,46vw,700px);overflow:hidden}
.hero-ph{position:absolute;inset:0 0 0 18%;overflow:hidden}
.hero-fr{position:absolute;inset:-3%;transition:transform .8s cubic-bezier(.2,.7,.2,1)}
.hero-fr img{width:100%;height:100%;object-fit:cover}
.hero-ph::after{content:"";position:absolute;inset:0;background:linear-gradient(90deg,#F2E1C6 0,rgba(242,225,198,.88) 30%,rgba(242,225,198,0) 52%)}
.hero-dims{position:absolute;inset:0;width:100%;height:100%;pointer-events:none}
.hero-dims .dl{stroke:#fff;stroke-width:2.4;fill:none;stroke-dasharray:var(--len);stroke-dashoffset:var(--len);animation:draw 1.2s .5s cubic-bezier(.3,.7,.2,1) forwards}
.hero-dims .dl.d2{animation-delay:.9s}.hero-dims .dl.d3{animation-delay:1.2s}.hero-dims .dl.d4{animation-delay:1.5s}
.hero-dims text{font:600 22px var(--mono);fill:#fff;opacity:0;animation:pop .5s forwards;paint-order:stroke;stroke:rgba(90,60,30,.5);stroke-width:4px}
.hero-dims .t1{animation-delay:1.3s}.hero-dims .t2{animation-delay:1.6s}.hero-dims .t3{animation-delay:1.9s}.hero-dims .t4{animation-delay:2.1s}
.hero-dims .tag{opacity:0;animation:pop .5s 1.1s forwards}
.hero .wrap{position:relative;z-index:3;padding-top:128px}
.hero h1{font-size:clamp(40px,4.6vw,66px);line-height:1.04;font-weight:800;max-width:720px;letter-spacing:-.035em}
.hero .lead{font-size:19px;max-width:520px;color:var(--ink2);margin:24px 0 30px}
.hero .dash{display:block;width:72px;height:3px;background:var(--acc);border-radius:2px;transform-origin:left;animation:grow .8s 1s both}
.hero .go{display:inline-flex;align-items:center;gap:12px;margin-top:30px;font-weight:600;text-decoration:none;border-bottom:1.5px solid var(--ink);padding-bottom:4px}
.hero .go svg{width:16px;height:16px;transition:transform .2s}
.hero .go:hover svg{transform:translateY(3px)}
@keyframes draw{to{stroke-dashoffset:0}}
@keyframes pop{from{opacity:0;translate:0 6px}to{opacity:1;translate:0 0}}
@keyframes grow{from{transform:scaleX(0)}}

/* ——— калькулятор ——— */
.calc{display:grid;grid-template-columns:400px 1fr;gap:44px;align-items:start}
.fields{display:grid;gap:16px}
.fld{display:grid;grid-template-columns:1fr 168px;gap:18px;align-items:center}
.fld label{font-size:16px;color:var(--ink2);line-height:1.3}
.fld label small{display:block;color:var(--mute);font-size:13px}
.inp{position:relative}
.inp input{width:100%;background:rgba(255,250,240,.75);border:1px solid rgba(110,80,45,.28);border-radius:8px;padding:12px 44px 12px 16px;
  font:500 20px var(--mono);box-shadow:inset 0 2px 4px rgba(90,60,30,.08);transition:border-color .2s,box-shadow .2s}
.inp input:focus{outline:0;border-color:var(--acc);box-shadow:inset 0 2px 4px rgba(90,60,30,.08),0 0 0 3px rgba(232,113,28,.18)}
.inp span{position:absolute;right:14px;top:50%;transform:translateY(-50%);font:13px var(--mono);color:var(--mute)}
.steps-adj{display:flex;align-items:center;gap:10px;margin-top:6px;padding-top:18px;border-top:1px dashed var(--line);font-size:15px;color:var(--ink2)}
.steps-adj .ctr{display:flex;align-items:center;border:1px solid rgba(110,80,45,.28);border-radius:8px;overflow:hidden;margin-left:auto;background:rgba(255,250,240,.75)}
.steps-adj button{border:0;background:none;width:40px;height:40px;font:600 20px var(--mono)}
.steps-adj button:hover{background:rgba(232,113,28,.12)}
.steps-adj output{min-width:44px;text-align:center;font:600 18px var(--mono)}
.steps-adj .auto{border:0;background:none;color:var(--acc);font-size:14px;text-decoration:underline;padding:0}
.hint{font-size:14px;color:var(--mute);margin:14px 0 0;line-height:1.45}
.draw{position:relative;border-radius:4px;background-color:rgba(255,250,240,.35);
  background-image:linear-gradient(var(--grid) 1px,transparent 1px),linear-gradient(90deg,var(--grid) 1px,transparent 1px),
  linear-gradient(rgba(90,70,45,.05) 1px,transparent 1px),linear-gradient(90deg,rgba(90,70,45,.05) 1px,transparent 1px);
  background-size:50px 50px,50px 50px,10px 10px,10px 10px}
.draw svg{width:100%;height:auto;display:block;overflow:visible}
.draw .dim{stroke:var(--ink);stroke-width:1;fill:none}
.draw .dimt{font:500 13px var(--mono);fill:var(--ink);paint-order:stroke;stroke:#F6E9D4;stroke-width:4px}
.draw .lab{font:500 12.5px var(--text);fill:var(--ink2);paint-order:stroke;stroke:#F6E9D4;stroke-width:4px}
.draw .tread{transition:transform .5s cubic-bezier(.2,.7,.2,1)}
.draw .head{stroke:var(--acc);stroke-width:1.6;stroke-dasharray:5 4;fill:none}
.draw .headt{font:600 13.5px var(--mono);fill:var(--acc);paint-order:stroke;stroke:#F6E9D4;stroke-width:4px}
.draw .bad .headt{fill:#C7361B}
.res{display:grid;grid-template-columns:1.55fr repeat(4,1fr);margin-top:30px;border:1px solid rgba(110,80,45,.22);border-radius:10px;background:var(--card);
  box-shadow:0 10px 30px rgba(90,60,30,.08)}
.res>div{padding:20px 24px;border-left:1px solid var(--line)}
.res>div:first-child{border-left:0;display:flex;gap:16px;align-items:center}
.res small{display:block;font-size:13.5px;color:var(--ink2)}
.res b{display:block;font:500 26px var(--mono);margin-top:6px;letter-spacing:-.02em}
.res .chk{width:46px;height:46px;border-radius:50%;background:var(--ok);display:grid;place-items:center;flex:none;transition:background .3s}
.res .chk svg{width:24px;height:24px}
.res .chk.warn{background:var(--warn)}
.res .f{font:600 19px var(--mono);white-space:nowrap}
.res .f+small{margin-top:4px}
.res b.flash{animation:flash .5s}
@keyframes flash{from{color:var(--acc)}}
.notes{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin-top:22px}
.notes p{margin:0;font-size:14.5px;color:var(--ink2);padding-left:16px;border-left:2px solid var(--acc);line-height:1.45}
.notes p.bad{border-color:#C7361B;color:#7d2412}

/* ——— типы ——— */
.tipy{display:grid;grid-template-columns:repeat(4,1fr);gap:18px}
.tip{background:var(--card);border:1px solid rgba(110,80,45,.18);border-radius:12px;padding:22px 22px 24px;display:flex;flex-direction:column;
  transition:transform .35s cubic-bezier(.2,.7,.2,1),box-shadow .35s,background .3s;cursor:default}
.tip:hover{transform:translateY(-4px);box-shadow:0 18px 40px rgba(90,60,30,.14);background:rgba(255,250,240,.8)}
.tip h3{font-size:19px;line-height:1.2;min-height:46px}
.tip .iso{height:210px;display:grid;place-items:center;margin:6px 0 4px}
.tip .iso img{max-height:210px;width:auto;filter:drop-shadow(0 14px 14px rgba(90,60,30,.16));transition:transform .5s cubic-bezier(.2,.7,.2,1)}
.tip:hover .iso img{transform:scale(1.04) rotate(-1deg)}
.tip .plan{height:98px;margin:6px 0 4px}
.tip .plan svg{width:100%;height:100%}
.tip .size{font:500 13px var(--mono);color:var(--ink2);text-align:center;margin:2px 0 14px;min-height:20px}
.tip ul{list-style:none;padding:0;margin:auto 0 0;display:grid;gap:10px;font-size:15px;line-height:1.4}
.tip li{display:grid;grid-template-columns:22px 1fr;gap:8px}
.tip li svg{width:18px;height:18px;margin-top:2px}

/* ——— ошибки ——— */
.osh{display:grid;grid-template-columns:repeat(5,1fr);gap:14px}
.o{position:relative;perspective:1200px;min-height:420px}
.o-in{position:absolute;inset:0;transition:transform .7s cubic-bezier(.3,.7,.2,1);transform-style:preserve-3d}
.o.flip .o-in{transform:rotateY(180deg)}
.o-f,.o-b{position:absolute;inset:0;backface-visibility:hidden;background:var(--card);border:1px solid rgba(110,80,45,.18);border-radius:12px;padding:18px 18px 20px;display:flex;flex-direction:column}
.o-b{transform:rotateY(180deg);background:#FBF1E1}
.o h3{font-size:16px;line-height:1.25;min-height:40px;display:flex;gap:6px}
.o .pic{flex:1;display:grid;place-items:center;margin:8px 0 10px;min-height:160px}
.o .pic img{max-height:170px;width:auto}
.o p{margin:0;font-size:14.5px;line-height:1.45;color:var(--ink2)}
.o .flipb{margin-top:14px;align-self:flex-start;border:0;background:none;padding:0;font-size:14px;font-weight:600;color:var(--acc);display:flex;gap:6px;align-items:center}
.o .flipb svg{width:14px;height:14px}
.o-b h4{margin:0 0 10px;font:700 13px var(--mono);text-transform:uppercase;letter-spacing:.06em;color:var(--acc)}
.o-b p+h4{margin-top:16px}

/* ——— дерево ——— */
.drevo{display:grid;grid-template-columns:repeat(5,1fr);gap:22px}
.porod{border:0;background:none;padding:0;text-align:left;cursor:pointer;display:flex;flex-direction:column;justify-content:flex-start}
.porod h3{font-size:18px;margin-bottom:12px}
.porod .blk{height:150px;display:grid;place-items:center}
.porod .blk img{max-height:150px;width:auto;filter:drop-shadow(0 16px 14px rgba(90,60,30,.18));transition:transform .45s cubic-bezier(.2,.7,.2,1)}
.porod:hover .blk img,.porod.on .blk img{transform:translateY(-8px) rotate(-2deg)}
.porod p{margin:14px 0 0;font-size:14.5px;color:var(--ink2);line-height:1.45}
.porod.on h3{color:var(--acc)}
.shkala{position:relative;margin:34px 0 0;height:54px}
.shkala .ln{position:absolute;left:90px;right:96px;top:13px;height:3px;border-radius:2px;background:linear-gradient(90deg,#F6D49B,var(--acc))}
.shkala .ln::after{content:"";position:absolute;right:-12px;top:-6px;border:7.5px solid transparent;border-left:13px solid var(--acc)}
.shkala .l,.shkala .r{position:absolute;top:2px;font-weight:600;color:var(--acc);font-size:17px}
.shkala .l{left:0;color:var(--acc2)}.shkala .r{right:0}
.shkala .dot{position:absolute;top:7px;width:15px;height:15px;margin-left:-7.5px;border-radius:50%;background:#E8A86A;border:2px solid #F3E3CA;transition:transform .3s,background .3s}
.shkala .dot.on{background:var(--acc);transform:scale(1.5)}
.shkala .dot span{position:absolute;top:22px;left:50%;transform:translateX(-50%);font:500 11.5px var(--mono);white-space:nowrap;color:var(--ink2);opacity:0;transition:opacity .3s}
.shkala .dot.on span{opacity:1}
.shkala-note{font-size:13.5px;color:var(--mute);margin:8px 0 0}
.more{display:inline-flex;align-items:center;gap:12px;margin-top:26px;background:var(--ink);color:#F6E8D2;text-decoration:none;border-radius:40px;padding:15px 26px;font-weight:600;transition:transform .2s,background .2s}
.more:hover{background:#000;transform:translateY(-2px)}
.more svg{width:16px;height:16px;transition:transform .2s}
.more:hover svg{transform:translateX(4px)}

/* ——— вопросы ——— */
.faq{display:grid;grid-template-columns:1fr 1fr;gap:14px;align-items:start}
.faq details{background:var(--card);border:1px solid rgba(110,80,45,.2);border-radius:8px;transition:background .2s}
.faq details[open]{background:rgba(255,250,240,.85)}
.faq summary{list-style:none;cursor:pointer;padding:18px 22px;font-weight:500;display:flex;justify-content:space-between;gap:16px;align-items:center}
.faq summary::-webkit-details-marker{display:none}
.faq summary svg{width:16px;height:16px;flex:none;transition:transform .3s}
.faq details[open] summary svg{transform:rotate(180deg)}
.faq details p{margin:0;padding:0 22px 20px;color:var(--ink2);font-size:15.5px}

/* ——— подвал ——— */
.foot{position:relative;padding:40px 0 34px}
.foot::before{content:"";position:absolute;left:0;right:0;top:0;height:7px;background:linear-gradient(180deg,rgba(120,80,40,.28),rgba(120,80,40,0))}
.foot .wrap{display:flex;align-items:center;gap:40px}
.foot nav{margin-left:auto;display:flex;gap:30px;font-size:14px}
.foot nav a{text-decoration:none;border-bottom:1px solid transparent}
.foot nav a:hover{border-color:currentColor}
.foot .sk{width:150px;height:90px;opacity:.6}
.foot small{color:var(--mute);font-size:13px}

/* проявление при прокрутке */
.rv{opacity:0;transform:translateY(26px);transition:opacity .8s,transform .8s cubic-bezier(.2,.7,.2,1)}
.rv.on{opacity:1;transform:none}

@media (max-width:1100px){
  .calc{grid-template-columns:1fr}
  .tipy{grid-template-columns:repeat(2,1fr)}
  .osh{grid-template-columns:repeat(3,1fr)}
  .res{grid-template-columns:1fr 1fr}
  .res>div:first-child{grid-column:1/-1}
  .res>div{border-left:0;border-top:1px solid var(--line)}
  .res>div:first-child{border-top:0}
  .drevo{grid-template-columns:repeat(3,1fr)}
  .shkala{display:none}
}
@media (max-width:700px){
  .wrap{padding:0 18px}
  .top .wrap{padding-top:16px}
  .hero{height:auto;padding-bottom:300px}
  .hero-ph{inset:auto 0 0 0;height:320px}
  .hero-ph::after{background:linear-gradient(180deg,#F2E1C6 0,rgba(242,225,198,0) 40%)}
  .hero .wrap{padding-top:96px}
  .hero-dims{display:none}
  .fld{grid-template-columns:1fr 140px;gap:12px}
  .notes{grid-template-columns:1fr}
  .tipy,.faq{grid-template-columns:1fr}
  .osh{grid-template-columns:1fr 1fr}
  .o{min-height:400px}
  .drevo{grid-template-columns:1fr 1fr}
  .menu{grid-template-columns:1fr}
  .menu aside{display:none}
  .menu nav{padding:100px 24px}
  .foot .wrap{flex-wrap:wrap;gap:16px}
  .foot nav{margin-left:0}
  .foot .sk{display:none}
}
@media (max-width:440px){ .osh{grid-template-columns:1fr} .o{min-height:380px} }
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.01ms!important;animation-delay:0s!important;transition-duration:.01ms!important}
  .rv{opacity:1;transform:none}
}