/*
 * New-Science.ru Scientific Laboratory
 * Physics 9 Class Hub — v2
 * https://new-science.ru/lab/9-klass/fizika/
 * Copyright © New-Science.ru
 */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&family=Manrope:wght@500;600;700;800&display=swap');

:root{
  --bg:#050912;
  --panel:#091523;
  --panel-2:#0d1b2c;
  --panel-3:#07111e;
  --line:rgba(255,255,255,.095);
  --line-strong:rgba(85,214,255,.25);
  --text:#f5f8fd;
  --muted:#9aadc4;
  --blue:#55d6ff;
  --indigo:#7786ff;
  --green:#5bd9a7;
  --orange:#ffb45f;
  --shadow:0 28px 80px rgba(0,0,0,.24);
}

*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:24px}
body{
  margin:0;
  color:var(--text);
  font-family:Inter,Arial,sans-serif;
  line-height:1.55;
  background:
    radial-gradient(circle at 12% 4%,rgba(58,126,194,.18),transparent 25%),
    radial-gradient(circle at 88% 14%,rgba(85,214,255,.07),transparent 26%),
    radial-gradient(circle at 55% 55%,rgba(119,134,255,.035),transparent 30%),
    var(--bg);
}
a{color:inherit}
button,input,select{font:inherit}
.page-shell{overflow:hidden}

.site-header{
  max-width:1240px;
  margin:auto;
  padding:21px 28px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:24px;
}
.brand img{display:block;width:208px;max-width:44vw;height:auto}
.header-nav{display:flex;gap:24px;color:var(--muted);font-size:14px}
.header-nav a{text-decoration:none}
.header-nav a:hover,.header-nav a.active{color:var(--text)}

main{max-width:1240px;margin:auto;padding:0 28px 80px}
.breadcrumbs{display:flex;align-items:center;gap:9px;flex-wrap:wrap;margin-top:18px;color:#8194aa;font-size:13px}
.breadcrumbs a{text-decoration:none}
.breadcrumbs a:hover{color:var(--blue)}

.eyebrow,.kicker{color:var(--blue);font-weight:800;font-size:12px;letter-spacing:.17em}

.hero{
  min-height:650px;
  display:grid;
  grid-template-columns:1.05fr .95fr;
  align-items:center;
  gap:68px;
  padding:74px 0 48px;
}
.hero-copy{min-width:0}
.hero h1{
  max-width:720px;
  margin:17px 0 23px;
  font:800 clamp(48px,5.2vw,76px)/1.01 Manrope,Inter,sans-serif;
  letter-spacing:-.05em;
}
.hero h1 span{
  background:linear-gradient(90deg,var(--blue),#bbc4ff);
  -webkit-background-clip:text;
  background-clip:text;
  color:transparent;
}
.lead{max-width:700px;color:#b5c5d8;font-size:19px}
.hero-actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:31px}
.btn{
  min-height:50px;
  padding:0 21px;
  border-radius:13px;
  display:inline-flex;
  align-items:center;
  justify-content:center;
  text-decoration:none;
  font-weight:750;
  border:1px solid transparent;
  transition:.2s ease;
}
.btn.primary{background:linear-gradient(135deg,var(--blue),#607cff);color:#03101a}
.btn.secondary{background:rgba(255,255,255,.03);border-color:var(--line)}
.btn:hover{transform:translateY(-2px)}
.btn:focus-visible{outline:2px solid var(--blue);outline-offset:4px}

.hero-stats{display:flex;gap:35px;flex-wrap:wrap;margin-top:42px}
.hero-stats div{display:flex;flex-direction:column}
.hero-stats strong{font:800 26px Manrope}
.hero-stats span{font-size:13px;color:var(--muted)}

.hero-map{
  min-height:500px;
  position:relative;
  overflow:hidden;
  border:1px solid var(--line);
  border-radius:34px;
  background:
    radial-gradient(circle at 50% 45%,rgba(85,214,255,.11),transparent 34%),
    linear-gradient(150deg,#09192a,#06111e);
  box-shadow:var(--shadow);
}
.hero-grid{
  position:absolute;
  inset:0;
  background:
    linear-gradient(rgba(255,255,255,.024) 1px,transparent 1px),
    linear-gradient(90deg,rgba(255,255,255,.024) 1px,transparent 1px);
  background-size:28px 28px;
  mask-image:linear-gradient(to bottom,black,transparent 92%);
}
.hero-core{
  position:absolute;
  left:50%;
  top:48%;
  width:154px;
  height:154px;
  transform:translate(-50%,-50%);
  border:1px solid rgba(85,214,255,.34);
  border-radius:50%;
  display:flex;
  flex-direction:column;
  align-items:center;
  justify-content:center;
  background:radial-gradient(circle,rgba(85,214,255,.14),rgba(7,17,30,.92) 68%);
  box-shadow:0 0 60px rgba(85,214,255,.07),inset 0 0 30px rgba(85,214,255,.05);
  z-index:3;
}
.hero-core span,.hero-core small{font-size:9px;letter-spacing:.19em;color:#9eb3c9;font-weight:800}
.hero-core strong{font:800 58px/1 Manrope;margin:4px 0;color:#eafaff}
.orbit{position:absolute;left:50%;top:48%;transform:translate(-50%,-50%);border:1px solid rgba(255,255,255,.09);border-radius:50%}
.orbit-one{width:290px;height:290px}
.orbit-two{width:420px;height:420px;border-style:dashed;border-color:rgba(85,214,255,.13)}
.topic-dot{
  position:absolute;
  width:48px;
  height:48px;
  border-radius:50%;
  display:grid;
  place-items:center;
  border:1px solid rgba(85,214,255,.28);
  background:#0b1d2c;
  color:var(--blue);
  font:800 14px Manrope;
  z-index:4;
  box-shadow:0 10px 30px rgba(0,0,0,.25);
}
.dot-mechanics{left:15%;top:25%}
.dot-waves{right:15%;top:22%}
.dot-em{right:9%;bottom:23%}
.dot-light{left:19%;bottom:15%}
.dot-quantum{left:48%;bottom:5%;width:58px;height:58px;font-size:11px}
.hero-formula{
  position:absolute;
  z-index:2;
  padding:7px 10px;
  border:1px solid var(--line);
  border-radius:9px;
  background:rgba(6,16,28,.72);
  color:#91a9c2;
  font:700 11px Manrope;
}
.formula-one{left:8%;top:8%}
.formula-two{right:7%;top:9%}
.formula-three{right:6%;bottom:7%}
.formula-four{left:7%;bottom:8%}

.course-progress{
  margin:12px 0 92px;
  padding:20px 22px;
  border:1px solid rgba(85,214,255,.18);
  border-radius:19px;
  display:grid;
  grid-template-columns:1.25fr .75fr;
  align-items:center;
  gap:28px;
  background:linear-gradient(90deg,rgba(85,214,255,.07),rgba(119,134,255,.035));
}
.course-progress>div:first-child{display:flex;gap:15px;align-items:flex-start}
.spark{width:36px;height:36px;flex:0 0 36px;display:grid;place-items:center;border-radius:10px;background:rgba(85,214,255,.11);color:var(--blue)}
.course-progress p{margin:4px 0 0;color:var(--muted);font-size:14px}
.progress-box{min-width:0}
.progress-head{display:flex;justify-content:space-between;gap:12px;margin-bottom:9px;font-size:12px;color:var(--muted)}
.progress-head b{color:#d8e6f5}
.progress-track{height:7px;border-radius:999px;background:rgba(255,255,255,.06);overflow:hidden}
.progress-track span{display:block;height:100%;width:0;border-radius:inherit;background:linear-gradient(90deg,var(--blue),var(--indigo));transition:width .5s ease}

.section{margin:100px 0}
.section-head{display:flex;justify-content:space-between;align-items:end;gap:28px;margin-bottom:29px}
.section-head h2,.course-section-head h2,.how-it-works h2,.oge-section h2,.seo-content h2,.faq h2{
  margin:7px 0 0;
  font:800 clamp(31px,4vw,46px)/1.08 Manrope;
  letter-spacing:-.035em;
}
.section-head>p{max-width:510px;margin:0;color:var(--muted)}

.section-overview{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:12px}
.overview-card{
  min-height:170px;
  padding:18px;
  border:1px solid var(--line);
  border-radius:19px;
  display:flex;
  flex-direction:column;
  text-decoration:none;
  background:linear-gradient(150deg,rgba(14,27,46,.9),rgba(7,16,29,.96));
  transition:.2s ease;
}
.overview-card>span{font:800 11px Manrope;color:#667d96;letter-spacing:.12em}
.overview-card strong{margin:25px 0 auto;font:750 16px/1.3 Manrope}
.overview-card small{color:#71869e;font-size:11px;text-transform:uppercase;letter-spacing:.08em}
.overview-card small b{color:inherit}
.overview-card.active{border-color:rgba(85,214,255,.24);background:linear-gradient(150deg,rgba(17,47,67,.87),rgba(8,21,36,.97))}
.overview-card.active small{color:var(--green)}
.overview-card.current{box-shadow:inset 0 0 0 1px rgba(85,214,255,.34),0 14px 34px rgba(0,0,0,.14)}
.overview-card:hover{transform:translateY(-3px);border-color:rgba(85,214,255,.36)}
.overview-card:focus-visible{outline:2px solid var(--blue);outline-offset:4px}

.course-sections{margin-top:110px}
.course-section{
  position:relative;
  padding:34px 36px 38px;
  margin:0 0 26px;
  border:1px solid var(--line);
  border-radius:28px;
  background:
    radial-gradient(circle at 94% 0%,rgba(85,214,255,.065),transparent 22%),
    linear-gradient(145deg,rgba(11,25,42,.94),rgba(6,15,27,.98));
}
.course-section:target{border-color:rgba(85,214,255,.34)}
.course-section-head{
  display:grid;
  grid-template-columns:62px minmax(0,1fr) auto;
  gap:20px;
  align-items:start;
  padding-bottom:28px;
  border-bottom:1px solid var(--line);
}
.section-number{
  width:48px;
  height:48px;
  border-radius:14px;
  border:1px solid rgba(85,214,255,.19);
  display:grid;
  place-items:center;
  color:var(--blue);
  background:rgba(85,214,255,.055);
  font:800 12px Manrope;
}
.course-section-head h2{font-size:clamp(28px,3vw,40px)}
.course-section-head p{max-width:760px;margin:10px 0 0;color:var(--muted)}
.section-counter{min-width:88px;text-align:right}
.section-counter strong{display:block;font:800 28px Manrope;color:#e9f9ff}
.section-counter span{font-size:10px;text-transform:uppercase;letter-spacing:.11em;color:var(--muted)}

.topic-list{display:grid;gap:0}
.topic-card{
  min-height:124px;
  display:grid;
  grid-template-columns:52px minmax(0,1fr) auto;
  gap:18px;
  align-items:center;
  padding:22px 4px;
  border-bottom:1px solid var(--line);
}
.topic-card:last-child{border-bottom:0}
a.topic-card{text-decoration:none;transition:.18s ease}
a.topic-card:hover{padding-left:12px;padding-right:12px;background:rgba(85,214,255,.035)}
a.topic-card:focus-visible{outline:2px solid var(--blue);outline-offset:-2px;border-radius:10px}
.topic-index{font:800 11px Manrope;color:#60758d;align-self:start;padding-top:6px}
.topic-main{min-width:0}
.topic-title-row{display:flex;align-items:center;gap:12px;flex-wrap:wrap}
.topic-title-row h3{margin:0;font:750 19px/1.25 Manrope;letter-spacing:-.01em}
.topic-card p{max-width:820px;margin:7px 0 10px;color:var(--muted);font-size:13px}
.topic-tags{display:flex;gap:6px;flex-wrap:wrap}
.topic-tags span{padding:4px 7px;border-radius:7px;background:rgba(255,255,255,.035);border:1px solid rgba(255,255,255,.055);color:#849ab2;font-size:10px}
.state{display:inline-flex;align-items:center;min-height:23px;padding:0 8px;border-radius:999px;font-size:8px;font-weight:800;letter-spacing:.1em}
.ready-state{color:var(--green);border:1px solid rgba(91,217,167,.22);background:rgba(91,217,167,.075)}
.planned-state{color:#8599ae;border:1px solid rgba(255,255,255,.075);background:rgba(255,255,255,.025)}
.topic-open{align-self:center;color:var(--blue);font-size:12px;font-weight:700;white-space:nowrap}
.topic-open span{display:inline-block;margin-left:5px;transition:transform .18s ease}
a.topic-card:hover .topic-open span{transform:translateX(4px)}
.topic-card.planned{opacity:.74}

.how-it-works{padding-top:16px}
.principles{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px}
.principles div{
  min-height:190px;
  padding:20px;
  border:1px solid var(--line);
  border-radius:18px;
  background:rgba(255,255,255,.022);
}
.principles b{display:block;color:var(--blue);font:800 11px Manrope}
.principles strong{display:block;margin:32px 0 7px;font:750 17px Manrope}
.principles span{font-size:12px;color:var(--muted)}

.oge-section{
  display:grid;
  grid-template-columns:.9fr 1.1fr;
  gap:48px;
  align-items:center;
  padding:36px;
  border:1px solid rgba(119,134,255,.22);
  border-radius:28px;
  background:
    radial-gradient(circle at 90% 0%,rgba(119,134,255,.11),transparent 30%),
    linear-gradient(145deg,rgba(13,25,46,.95),rgba(7,15,29,.98));
}
.oge-copy p{color:var(--muted);max-width:610px}
.oge-preview{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px}
.oge-preview div{min-height:150px;padding:18px;border:1px solid var(--line);border-radius:16px;background:rgba(255,255,255,.025);display:flex;flex-direction:column}
.oge-preview span{font:800 10px Manrope;color:#7188a4}
.oge-preview b{margin:auto 0 3px;font:750 17px Manrope}
.oge-preview small{color:var(--muted)}

.seo-content{display:grid;grid-template-columns:1.08fr .92fr;gap:48px;align-items:start}
.content-column p,.seo-side p{color:var(--muted);font-size:15px}
.seo-side{padding:24px;border-left:2px solid rgba(85,214,255,.22);background:linear-gradient(90deg,rgba(85,214,255,.035),transparent)}
.seo-side strong{font:750 18px Manrope}
.seo-side a{display:inline-block;margin-top:9px;color:var(--blue);font-size:13px;font-weight:700;text-decoration:none}
.seo-side a:hover{text-decoration:underline}

.faq details{border-top:1px solid var(--line);padding:18px 0}
.faq details:last-child{border-bottom:1px solid var(--line)}
.faq summary{cursor:pointer;font-weight:700}
.faq details p{color:var(--muted);max-width:860px}

.back-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin:105px 0 25px}
.back-links a{
  min-height:112px;
  border:1px solid var(--line);
  border-radius:19px;
  padding:20px;
  text-decoration:none;
  background:rgba(255,255,255,.025);
  display:flex;
  flex-direction:column;
  justify-content:center;
}
.back-links a:hover{border-color:rgba(85,214,255,.28)}
.back-links small{color:var(--muted);font-size:9px;letter-spacing:.13em;margin-bottom:6px}
.back-links strong{font:750 18px Manrope}

.footer{
  max-width:1240px;
  margin:auto;
  border-top:1px solid var(--line);
  padding:34px 28px 45px;
  display:flex;
  justify-content:space-between;
  gap:30px;
  color:var(--muted);
}
.footer img{width:190px;max-width:60vw}
.footer p{max-width:570px;font-size:13px}
.footer nav{display:flex;gap:18px;flex-wrap:wrap;align-items:flex-start}
.footer a{text-decoration:none;font-size:13px}
.footer a:hover{color:var(--text)}

@media (max-width:1100px){
  .section-overview{grid-template-columns:repeat(3,minmax(0,1fr))}
  .principles{grid-template-columns:repeat(2,minmax(0,1fr))}
}

@media (max-width:1000px){
  .hero{grid-template-columns:1fr;gap:30px;padding-top:60px}
  .hero-map{min-height:470px}
  .course-progress{grid-template-columns:1fr}
  .oge-section,.seo-content{grid-template-columns:1fr}
}

@media (max-width:760px){
  .site-header{padding:17px 18px}
  .header-nav{display:none}
  main{padding:0 18px 60px}
  .hero{min-height:auto;padding:50px 0 38px}
  .hero h1{font-size:clamp(40px,11vw,56px)}
  .lead{font-size:17px}
  .hero-map{min-height:410px;border-radius:25px}
  .hero-stats{gap:22px}
  .course-progress{margin-bottom:76px}
  .section{margin:82px 0}
  .section-head{align-items:flex-start;flex-direction:column}
  .section-overview{grid-template-columns:repeat(2,minmax(0,1fr))}
  .course-sections{margin-top:84px}
  .course-section{padding:25px 21px 28px;border-radius:23px}
  .course-section-head{grid-template-columns:48px minmax(0,1fr);gap:14px}
  .section-counter{grid-column:2;text-align:left;display:flex;align-items:baseline;gap:7px}
  .section-counter strong{font-size:20px}
  .topic-card{grid-template-columns:34px minmax(0,1fr);gap:10px;padding:18px 0}
  .topic-open{grid-column:2;justify-self:start;margin-top:0}
  a.topic-card:hover{padding-left:6px;padding-right:6px}
  .principles{grid-template-columns:1fr 1fr}
  .oge-section{padding:25px 21px}
  .oge-preview{grid-template-columns:1fr}
  .oge-preview div{min-height:105px}
  .back-links{grid-template-columns:1fr}
  .footer{padding:30px 18px;flex-direction:column}
}

@media (max-width:500px){
  .brand img{width:174px;max-width:72vw}
  .hero-actions .btn{width:100%}
  .hero-map{min-height:360px}
  .hero-core{width:126px;height:126px}
  .hero-core strong{font-size:48px}
  .orbit-one{width:235px;height:235px}
  .orbit-two{width:320px;height:320px}
  .topic-dot{width:40px;height:40px;font-size:12px}
  .dot-quantum{width:48px;height:48px;font-size:9px}
  .formula-three,.formula-four{display:none}
  .section-overview{grid-template-columns:1fr}
  .overview-card{min-height:125px}
  .overview-card strong{margin:18px 0 auto}
  .principles{grid-template-columns:1fr}
  .topic-title-row{align-items:flex-start;flex-direction:column;gap:7px}
  .topic-title-row h3{font-size:18px}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *{transition:none!important}
}