/* === LOET — Laboratory of Optoelectronic Technique === */
/* Precision instrumentation aesthetic */

:root {
  --bg:       #f4f5f7;
  --surface:  #fdfdfd;
  --header:   #1a1f2b;
  --accent:   #c07840;
  --accent-dim:rgba(192,120,64,.12);
  --link:     #3a5070;
  --link-h:   #c07840;
  --text:     #2a2f38;
  --text-dim: #6b7280;
  --border:   #e2e5ea;
  --hover:    #f0f2f5;
  --active:   #e8ebf0;
  --code-bg:  #f8f9fb;
  --radius:   2px;
  --mono:     'SF Mono', 'Cascadia Code', 'Consolas', 'Liberation Mono', monospace;
}

* { box-sizing: border-box; }

body {
  margin: 0; padding: 0;
  font-family: 'Inter', 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
  font-size: 15.5px; line-height: 1.72;
  color: var(--text);
  background: var(--bg);
  min-height: 100vh;
  display: flex; flex-direction: column;
  -webkit-font-smoothing: antialiased;
}

::selection { background: var(--accent-dim); color: var(--header); }

/* === Links === */
a {
  color: var(--link); text-decoration: none;
  transition: color .15s, background .15s;
}
a:hover { color: var(--link-h); }

/* === Headings — datasheet precision === */
h1 {
  font-family: var(--mono); font-size: .95em;
  font-weight: 400; letter-spacing: .08em;
  color: #96a0b0; margin: 0;
  text-transform: uppercase;
}
h2 {
  font-family: var(--mono); font-size: 1em;
  font-weight: 500; color: var(--text-dim);
  text-transform: uppercase; letter-spacing: .08em;
  margin: 2em 0 .6em;
  padding-bottom: .35em;
  border-bottom: 1px solid var(--border);
}
h2::before { content: '§ '; color: var(--accent); font-weight: 400; }
h3 { font-size: 1.05em; font-weight: 600; color: var(--header); margin: 1.2em 0 .35em; }
h4 { font-size: .95em; font-weight: 600; color: var(--text-dim); text-transform: uppercase; letter-spacing: .05em; }

/* === Dividers === */
hr       { border: none; border-top: 1px solid var(--border); margin: 24px 0; }
hr.sep   { border: none; border-top: 1px solid var(--border); max-width: 400px; margin: 28px auto; position: relative; }
hr.sep::after {
  content: '◆'; position: absolute; top: -9px; left: 50%;
  transform: translateX(-50%); background: var(--bg);
  padding: 0 10px; color: var(--accent); font-size: .55em;
}

/* === Header — instrument panel === */
header {
  background: var(--header);
  color: #96a0b0;
  padding: 18px 32px 14px;
  display: flex; flex-wrap: wrap; align-items: center;
  gap: 18px;
  box-shadow: 0 1px 0 rgba(255,255,255,.04) inset,
              0 6px 24px rgba(0,0,0,.14);
  position: relative; z-index: 10;
}
header::after {
  content: ''; position: absolute; bottom: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent) 0%, var(--accent) 40%, transparent 40%);
}

header .logo { flex-shrink: 0; }
header .logo img {
  width: 40px; height: 40px;
  vertical-align: middle; border: 0;
  opacity: .85; filter: grayscale(20%);
  transition: opacity .2s, filter .2s;
}
header .logo:hover img { opacity: 1; filter: grayscale(0); }

header h1 {
  flex: 1; min-width: 180px;
  font-family: var(--mono); font-weight: 300; font-size: 1em;
  letter-spacing: .06em; color: #708090;
  text-transform: uppercase;
}

header .lang-links {
  display: flex; gap: 1px; align-items: center;
  font-family: var(--mono); font-size: .94em;
  letter-spacing: .04em; text-transform: uppercase;
}
header .lang-links a, header .lang-links span {
  color: rgba(150,160,176,.55);
  padding: 4px 12px; border: 1px solid transparent;
  transition: all .15s;
}
header .lang-links a:hover {
  color: #c0c8d4; border-color: rgba(150,160,176,.2);
  background: rgba(255,255,255,.03);
  text-decoration: none;
}
header .lang-links span { color: #9098a4; }

/* === Layout === */
.wrap { display: flex; flex: 1; }

nav {
  width: 190px; flex-shrink: 0;
  padding: 30px 0;
  background: var(--surface);
  border-right: 1px solid var(--border);
}

nav a {
  display: block;
  padding: 7px 24px;
  font-size: .94em; color: var(--text-dim);
  font-family: var(--mono); letter-spacing: .03em;
  border-left: 2px solid transparent;
  transition: all .15s;
}
nav a:hover {
  background: var(--hover); color: var(--text);
  border-left-color: var(--accent);
  text-decoration: none;
}
nav .active {
  display: block;
  padding: 7px 24px;
  font-size: .94em; font-family: var(--mono);
  font-weight: 600; letter-spacing: .03em;
  color: var(--header); background: var(--active);
  border-left: 2px solid var(--accent);
}

main {
  flex: 1; min-width: 0;
  padding: 34px 40px;
  background: var(--surface);
}
main > hr:first-child { display: none; }

main img {
  max-width: 100%; height: auto;
  border: 1px solid var(--border);
  padding: 4px; background: #fff;
}

/* === Zoomable === */
a.zoomable {
  cursor: zoom-in; display: inline-block;
  text-align: center;
  text-decoration: none;
}
a.zoomable img { transition: opacity .2s, border-color .2s; display: block; }
a.zoomable:hover img { opacity: .78; border-color: var(--accent); }
.zoom-hint {
  display: block;
  font-family: var(--mono); font-size: .68em;
  color: var(--text-dim); letter-spacing: .04em;
  margin-top: 4px; margin-bottom: 16px;
  cursor: zoom-in;
}

/* === Footer === */
footer {
  text-align: center;
  padding: 20px 28px;
  border-top: 1px solid var(--border);
  background: var(--bg);
  font-family: var(--mono); font-size: .94em;
  color: var(--text-dim); letter-spacing: .03em;
  margin-top: auto;
}
footer a { display: inline-block; margin: 0 10px; font-size: .9em; color: var(--text-dim); }
footer a:hover { color: var(--accent); }
footer .active { display: inline-block; margin: 0 10px; font-weight: 600; color: var(--text); }

/* === Tables — lab data === */
main table {
  border-collapse: collapse;
  font-family: var(--mono);
}
main td, main th {
  padding: 6px 14px;
  border: 1px solid var(--border);
}
main th {
  background: var(--code-bg);
  font-weight: 500; text-transform: uppercase;
  letter-spacing: .05em; font-size: .8em; color: var(--text-dim);
}

/* === Lists === */
main ul, main ol, main dl { padding-left: 1.6em; }
main li { margin: 4px 0; }

/* === Legacy table-bullets === */
.bullet {
  display: inline-block; width: 12px; height: 12px;
  margin: 0 15px; vertical-align: baseline;
  background: var(--accent);
  clip-path: polygon(50% 0%, 100% 38%, 82% 100%, 18% 100%, 0% 38%);
}

/* === Responsive === */
@media (max-width: 800px) {
  .wrap { flex-direction: column; }
  nav {
    width: 100%; border-right: none; border-bottom: 1px solid var(--border);
    padding: 12px 16px;
  }
  nav a { display: inline-block; border-left: none; border-bottom: 2px solid transparent; margin: 0 6px 0 0; padding: 4px 8px; }
  nav a:hover { border-left: none; border-bottom-color: var(--accent); }
  nav .active { display: inline-block; border-left: none; }
  main { padding: 20px 18px; }
  header { flex-direction: column; align-items: flex-start; gap: 8px; padding: 14px 20px 10px; }
  header h1 { font-size: .78em; }
  header::after { background: linear-gradient(90deg, var(--accent) 0%, var(--accent) 25%, transparent 25%); }
}
@media (max-width: 480px) {
  header { padding: 10px 14px 8px; }
  main { padding: 14px 12px; }
}