/* Site shell for the /research/ pages: the same tokens, navigation and footer as
   the front page, kept in one file so a new study is a new folder plus a card. */

/* ---------- tokens ---------- */
:root{
  --bg:#0b0c11;
  --bg-elev:#12141c;
  --surface:rgba(18,20,28,.82);
  --card-bg:rgba(18,20,28,.72);
  --text:#e9eaf0;
  --muted:#9298a8;
  --accent:#8b7cff;
  --accent-rgb:139,124,255;
  --accent-ink:#0b0c11;
  --border:rgba(139,124,255,.20);
  --border-soft:rgba(255,255,255,.08);
  --ok:#3ecf8e;
  --shadow:0 18px 40px -24px rgba(0,0,0,.8);

  --font-head:'Space Grotesk',system-ui,-apple-system,sans-serif;
  --font-body:'Inter',system-ui,-apple-system,sans-serif;
  --font-mono:'JetBrains Mono',ui-monospace,SFMono-Regular,monospace;

  --nav-h:60px;
  --content:920px;
  --section-gap:72px;
}
:root[data-theme="light"]{
  --bg:#f5f6f9;
  --bg-elev:#ffffff;
  --surface:rgba(255,255,255,.88);
  --card-bg:rgba(255,255,255,.86);
  --text:#14161f;
  --muted:#5b6172;
  --accent:#5b4fd6;
  --accent-rgb:91,79,214;
  --accent-ink:#ffffff;
  --border:rgba(91,79,214,.22);
  --border-soft:rgba(16,18,30,.10);
  --ok:#15803d;
  --shadow:0 18px 40px -28px rgba(20,22,50,.35);
}
:root[data-theme="cyber"]{
  --bg:#07070a;
  --bg-elev:#0d0d13;
  --surface:rgba(7,7,10,.92);
  --card-bg:rgba(13,13,19,.8);
  --text:#eef2f5;
  --muted:#7d8b96;
  --accent:#fcee0a;
  --accent-rgb:252,238,10;
  --accent-ink:#07070a;
  --border:rgba(252,238,10,.34);
  --border-soft:rgba(0,240,255,.20);
  --ok:#00f0ff;
  --shadow:0 0 0 1px rgba(0,240,255,.06), 0 18px 40px -26px rgba(0,240,255,.35);
  --cyan:#00f0ff;
  --hot:#ff003c;
}

*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:calc(var(--nav-h) + 16px)}
body{
  margin:0;
  background:var(--bg);
  color:var(--text);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.65;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
body::before{
  content:"";
  position:fixed;
  inset:0;
  pointer-events:none;
  z-index:0;
  background:
    radial-gradient(60% 45% at 78% -5%, rgba(var(--accent-rgb),.16), transparent 70%),
    radial-gradient(45% 35% at 0% 30%, rgba(var(--accent-rgb),.08), transparent 70%);
}
a{color:var(--accent);text-decoration:none}
h1,h2,h3,h4{font-family:var(--font-head);line-height:1.2;margin:0}
img{max-width:100%;display:block}
::selection{background:rgba(var(--accent-rgb),.3)}

/* text for screen readers and crawlers, not shown visually */
.sr-only{
  position:absolute;width:1px;height:1px;padding:0;margin:-1px;
  overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0;
}

/* ---------- nav ---------- */
.site-nav{
  position:fixed;top:0;left:0;right:0;z-index:50;
  height:var(--nav-h);
  display:flex;align-items:center;gap:1rem;
  padding:0 clamp(1rem,4vw,2rem);
  background:var(--surface);
  backdrop-filter:blur(14px);
  -webkit-backdrop-filter:blur(14px);
  border-bottom:1px solid transparent;
  transition:border-color .25s, background .25s;
}
.site-nav.is-scrolled{border-bottom-color:var(--border-soft)}
.nav-name{
  font-family:var(--font-head);font-weight:700;font-size:1rem;
  color:var(--text);letter-spacing:-.01em;margin-right:auto;white-space:nowrap;
}
.nav-name:hover{color:var(--accent)}
.nav-links{display:flex;gap:.35rem}
.nav-link{
  color:var(--muted);font-size:.9rem;font-weight:500;
  padding:.45rem .7rem;border-radius:7px;
  transition:color .2s, background .2s;
}
.nav-link:hover{color:var(--text);background:rgba(var(--accent-rgb),.08)}
.nav-link-active{color:var(--accent);background:rgba(var(--accent-rgb),.1)}
.nav-controls{display:flex;align-items:center;gap:.5rem}
.theme-switcher{display:flex;gap:2px;padding:3px;border-radius:9px;background:rgba(var(--accent-rgb),.08);border:1px solid var(--border-soft)}
.theme-btn{
  width:32px;height:28px;display:grid;place-items:center;
  border:0;border-radius:6px;background:transparent;color:var(--muted);cursor:pointer;
  transition:background .2s,color .2s;
}
.theme-btn:hover{color:var(--text)}
.theme-btn-active{background:var(--bg-elev);color:var(--accent)}
.theme-btn svg{width:15px;height:15px}
.nav-burger{
  display:none;position:relative;width:38px;height:34px;
  border:1px solid var(--border-soft);border-radius:8px;
  background:transparent;cursor:pointer;padding:0;
}
.nav-burger-line{
  position:absolute;left:50%;top:50%;width:16px;height:1.6px;margin-left:-8px;
  background:var(--text);border-radius:2px;transition:transform .25s,opacity .2s;
}
.nav-burger-line:nth-child(1){transform:translateY(-6px)}
.nav-burger-line:nth-child(3){transform:translateY(6px)}
.nav-burger[aria-expanded="true"] .nav-burger-line:nth-child(1){transform:rotate(45deg)}
.nav-burger[aria-expanded="true"] .nav-burger-line:nth-child(2){opacity:0}
.nav-burger[aria-expanded="true"] .nav-burger-line:nth-child(3){transform:rotate(-45deg)}

/* ---------- layout ---------- */
main{position:relative;z-index:1;max-width:var(--content);margin:0 auto;padding:0 clamp(1rem,4vw,2rem)}
.section-title{
  font-size:1.35rem;font-weight:600;color:var(--accent);
  margin-bottom:1.5rem;letter-spacing:-.01em;
}
.section-title::before{content:"— ";opacity:.45}

/* ---------- Speak-Y strip ---------- */
/* Вариант «outline»: рамка фирменного синего Speak-Y, одна строка текста и
   оранжевая кнопка — единственное яркое пятно. Цвета сняты со speak-y.com,
   поэтому блок читается одинаково на всех трёх темах сайта. */
:root{--sy-orange:#FF6700;--sy-orange-2:#E05A00;--sy-blue:#004E98;--sy-rule:#004E98}
:root[data-theme="dark"]{--sy-rule:#3A6EA5}
:root[data-theme="cyber"]{--sy-rule:rgba(0,240,255,.55)}
.sy-strip{
  position:relative;display:flex;align-items:center;flex-wrap:wrap;gap:.6rem 1.15rem;
  margin:0;padding:1rem 1.25rem;border:1.5px solid var(--sy-rule);border-radius:12px;
  background:transparent;font-size:.92rem;line-height:1.5;color:var(--muted);cursor:pointer;
}
.sy-name{
  font-family:var(--font-head);font-size:1.05rem;font-weight:700;letter-spacing:-.03em;
  color:var(--text);white-space:nowrap;
}
.sy-name i{font-style:normal;color:var(--sy-orange)}
.sy-strip p{margin:0;flex:1;min-width:14rem}
.sy-strip b{color:var(--text);font-weight:600}
.sy-strip a.sy-go{
  white-space:nowrap;padding:.55rem 1.1rem;border-radius:10px;
  background:var(--sy-orange);border:0;color:#fff;text-decoration:none;
  font-family:var(--font-head);font-size:.88rem;font-weight:600;letter-spacing:-.01em;
  transition:background .18s;
}
/* Кликается вся полоса, а не только кнопка. */
.sy-strip a.sy-go::after{content:"";position:absolute;inset:0;z-index:2}
.sy-strip:hover a.sy-go{background:var(--sy-orange-2);text-decoration:none}
@media (max-width:620px){
  .sy-strip{gap:.45rem .9rem}
  .sy-strip p{flex:1 0 100%}
  .sy-strip a.sy-go{flex:1 0 100%;text-align:center;margin-top:.15rem}
}
:root[data-theme="cyber"] .sy-strip{border-radius:0}
:root[data-theme="cyber"] .sy-strip a.sy-go{
  border-radius:0;text-transform:uppercase;letter-spacing:.08em;font-size:.76rem;
  font-family:var(--font-mono);
  clip-path:polygon(0 0, calc(100% - 9px) 0, 100% 9px, 100% 100%, 9px 100%, 0 calc(100% - 9px));
}

/* ---------- footer ---------- */
footer{
  position:relative;z-index:1;max-width:var(--content);margin:var(--section-gap) auto 0;
  padding:1.5rem clamp(1rem,4vw,2rem) 2.5rem;
  border-top:1px solid var(--border-soft);
  color:var(--muted);font-size:.82rem;
  display:flex;flex-wrap:wrap;gap:.5rem 1rem;justify-content:space-between;
}
footer .to-top{font-family:var(--font-mono);font-size:.8rem}

/* ---------- cyberpunk theme ---------- */
:root[data-theme="cyber"] body::after{
  content:"";position:fixed;inset:0;pointer-events:none;z-index:3;
  background:repeating-linear-gradient(to bottom,rgba(0,0,0,.22) 0 1px,transparent 1px 3px);
  opacity:.5;
}
:root[data-theme="cyber"] body::before{
  background:
    radial-gradient(55% 40% at 82% -5%, rgba(252,238,10,.14), transparent 70%),
    radial-gradient(45% 35% at -5% 25%, rgba(0,240,255,.12), transparent 70%),
    radial-gradient(40% 30% at 30% 105%, rgba(255,0,60,.10), transparent 70%);
}
:root[data-theme="cyber"] .section-title{
  text-transform:uppercase;letter-spacing:.16em;font-family:var(--font-mono);font-size:1.05rem;
  text-shadow:0 0 14px rgba(252,238,10,.45);
}
:root[data-theme="cyber"] .nav-link{text-transform:uppercase;letter-spacing:.1em;font-size:.78rem;font-family:var(--font-mono)}
:root[data-theme="cyber"] .nav-name{text-transform:uppercase;letter-spacing:.08em}
:root[data-theme="cyber"] .site-nav.is-scrolled{border-bottom-color:var(--accent)}

/* ---------- responsive ---------- */
@media (max-width:720px){
  .nav-burger{display:block}
  .nav-links{
    position:absolute;top:var(--nav-h);left:0;right:0;
    flex-direction:column;gap:0;padding:.5rem clamp(1rem,4vw,2rem) 1rem;
    background:var(--bg-elev);
    border-bottom:1px solid var(--border-soft);
    box-shadow:var(--shadow);
    display:none;
  }
  .nav-links.is-open{display:flex}
  .nav-link{padding:.7rem .5rem;font-size:.95rem}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation:none!important;transition:none!important}
}