/* ISMA 2027
   Two typefaces with fixed roles: Instrument Sans for words, IBM Plex Mono for labels and data.
   Six text sizes, three weights, one rule system (2px ink rule opens a group, 1px hairlines inside). */

@font-face {
  font-family: "Instrument Sans";
  src: url("../fonts/InstrumentSans-Variable.woff2") format("woff2");
  font-weight: 400 700;
  font-display: swap;
}
@font-face {
  font-family: "IBM Plex Mono";
  src: url("../fonts/IBMPlexMono-Regular.woff2") format("woff2");
  font-weight: 400;
  font-display: swap;
}

:root {
  /* colour: Cobalt */
  --bg: #F5F6F8;
  --panel: #E9ECF1;
  --text: #1B2230;
  --muted: #5A6273;
  --line: #D2D8E2;
  --acc: #2C4C9A;
  --deep: #1B2A4E;
  --on-deep: #C9D1E3;

  /* type */
  --sans: "Instrument Sans", system-ui, sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, monospace;
  --xs: 14px;
  --s: 15px;
  --m: 17px;
  --l: 21px;
  --xl: clamp(26px, 2.6vw, 34px);
  --xxl: clamp(88px, 19vw, 260px);
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: var(--m);
  line-height: 1.55;
  font-weight: 400;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}
main { flex: 1; }
a { color: inherit; }
img { max-width: 100%; height: auto; display: block; }
:focus-visible { outline: 2px solid var(--acc); outline-offset: 3px; }

.wrap { max-width: 1280px; margin: 0 auto; padding: 0 40px; }
.visually-hidden { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.skip { position: absolute; left: -9999px; top: 8px; background: var(--text); color: #fff; padding: 8px 14px; z-index: 10; }
.skip:focus { left: 8px; }

/* labels and data in mono */
.facts, td.time, .label, .tag, .dates .d {
  font-family: var(--mono);
  font-size: var(--xs);
  font-weight: 400;
}

/* ---------- header ---------- */
.site-head { position: sticky; top: 0; background: var(--bg); z-index: 5; border-bottom: 1px solid var(--line); }
.nav { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo { display: flex; align-items: center; gap: 10px; text-decoration: none; font-weight: 700; font-size: var(--m); }
.logo-ph { width: 30px; height: 30px; background: var(--panel); border: 1px solid var(--line); }
.links { display: flex; align-items: center; gap: 26px; font-size: var(--s); }
.links a { text-decoration: none; }
.links a:hover, .links a[aria-current="page"] { text-decoration: underline; text-underline-offset: 5px; text-decoration-thickness: 1px; }
.btn, .band a { border-radius: 999px; padding: 8px 18px; text-decoration: none; font-weight: 600; font-size: var(--s); }
.links .btn { background: var(--text); color: #fff; }
.links .btn:hover { background: var(--acc); text-decoration: none; }
.menu { display: none; }

/* ---------- home hero ---------- */
.hero { display: grid; grid-template-columns: repeat(12, 1fr); gap: 0 24px; padding: 56px 0 0; }
.hero .big { grid-column: 1 / -1; font-weight: 700; font-size: var(--xxl); line-height: .82; letter-spacing: -.045em; margin: 0; color: var(--acc); }
.hero .big span { color: var(--text); }
.hero h1 { grid-column: 1 / 7; font-size: var(--xl); line-height: 1.15; font-weight: 600; letter-spacing: -.01em; margin: 40px 0 0; }
.hero .facts { grid-column: 8 / -1; margin: 40px 0 0; }
.facts { border-top: 2px solid var(--text); }
.facts div { display: flex; justify-content: space-between; gap: 16px; padding: 10px 0; border-bottom: 1px solid var(--line); }
.facts span:first-child { color: var(--muted); }
.facts span:last-child { text-align: right; }
.facts a { text-decoration: none; }
.facts a:hover { text-decoration: underline; }

.band { background: var(--acc); color: #fff; margin-top: 56px; }
.band .wrap { display: flex; justify-content: space-between; align-items: center; padding-top: 22px; padding-bottom: 22px; gap: 24px; }
.band p { margin: 0; font-weight: 600; }
.band a { background: #fff; color: var(--acc); white-space: nowrap; }
.band a:hover { background: var(--panel); }

.img-ph { height: 420px; background: var(--panel); border-bottom: 1px solid var(--line); display: grid; place-items: center; }
.img-ph span { font-family: var(--mono); font-size: var(--xs); color: var(--muted); }
.hero-img { margin: 0; border-bottom: 1px solid var(--line); }
.hero-img img { width: 100%; height: 420px; object-fit: cover; }
.hero-img figcaption { font-size: var(--s); color: var(--muted); padding-top: 10px; padding-bottom: 10px; }

/* ---------- sections ---------- */
.sec { display: grid; grid-template-columns: repeat(12, 1fr); gap: 0 24px; padding: 88px 0; border-bottom: 1px solid var(--line); }
.sec:last-child { border-bottom: 0; }
.label { grid-column: 1 / 4; text-transform: uppercase; letter-spacing: .06em; color: var(--acc); margin: 6px 0 0; }
.sec .c { grid-column: 4 / -1; min-width: 0; }
.lead { font-size: var(--xl); line-height: 1.3; font-weight: 400; letter-spacing: -.01em; margin: 0 0 24px; max-width: 30ch; }
.body { color: var(--muted); max-width: 60ch; margin: 0; }
.body a { color: var(--acc); }
.tag { color: var(--muted); margin: 0 0 16px; }

.format { display: grid; grid-template-columns: repeat(2, 1fr); gap: 0 24px; margin: 48px 0 0; padding: 0; list-style: none; }
.format li { border-top: 2px solid var(--text); padding: 14px 0 28px; }
.format b { display: block; font-weight: 600; }
.format span { color: var(--muted); font-size: var(--s); }

/* programme */
table.programme { border-collapse: collapse; width: 100%; border-top: 2px solid var(--text); }
.programme td { padding: 13px 0; border-bottom: 1px solid var(--line); vertical-align: top; }
.programme td.time { width: 150px; color: var(--muted); padding-top: 15px; padding-right: 16px; white-space: nowrap; }
.programme .t { font-weight: 600; }
.programme .sub { display: block; color: var(--muted); font-size: var(--s); }
.programme tr.break td { background: var(--panel); }
.programme td:first-child { padding-left: 12px; }
.programme td:last-child { padding-right: 12px; }
.programme tr.break .t { font-weight: 400; color: var(--muted); }
.programme tr.round .t { color: var(--acc); }

/* participants */
ul.people { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px 24px; }
.people img, .people .mono-ph { aspect-ratio: 1; width: 100%; object-fit: cover; margin-bottom: 10px; }
.people .mono-ph { background: var(--panel); border: 1px solid var(--line); display: grid; place-items: center; font-weight: 700; font-size: var(--xl); color: var(--acc); letter-spacing: -.02em; }
.people .n { display: block; font-weight: 600; }
.people .i { display: block; color: var(--muted); font-size: var(--s); line-height: 1.4; }

/* key dates */
ul.dates { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
ul.dates li { border-top: 2px solid var(--text); padding-top: 12px; }
.dates .d { display: block; color: var(--muted); }
.dates .v { display: block; font-size: var(--l); font-weight: 600; line-height: 1.25; margin-top: 6px; }

/* sponsors */
ul.spons { list-style: none; margin: 0 0 24px; padding: 0; display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
ul.spons a { display: grid; place-items: center; height: 96px; padding: 16px; background: #fff; border: 1px solid var(--line); }
ul.spons img { max-height: 64px; width: auto; }

/* ---------- inner pages ---------- */
.page .c { grid-column: 1 / 10; }
.page-title { font-size: var(--xl); line-height: 1.15; font-weight: 600; letter-spacing: -.01em; margin: 0 0 32px; }
.prose { max-width: 68ch; }
.prose p, .prose ul { margin: 0 0 18px; }
.prose ul { padding-left: 20px; }
.prose li { margin-bottom: 6px; }
.prose h2 { font-size: var(--l); font-weight: 600; line-height: 1.25; margin: 48px 0 14px; padding-top: 12px; border-top: 2px solid var(--text); }
.prose a { color: var(--acc); }
.prose table.programme, .prose ul.people { margin: 8px 0 32px; }
.prose ul.people { padding-left: 0; max-width: none; }
.page .prose:has(ul.people) { max-width: none; }

/* ---------- footer ---------- */
.site-foot { background: var(--deep); color: var(--on-deep); padding: 56px 0 72px; font-size: var(--s); }
.foot { display: flex; justify-content: space-between; gap: 40px; }
.foot strong { color: #fff; font-weight: 600; }
.foot a { color: #fff; }

/* ---------- small screens ---------- */
@media (max-width: 900px) {
  .wrap { padding: 0 20px; }
  .links { display: none; }
  .menu { display: block; position: relative; }
  .menu summary { cursor: pointer; list-style: none; font-weight: 600; font-size: var(--s); padding: 6px 0; }
  .menu summary::-webkit-details-marker { display: none; }
  .menu div { position: absolute; right: 0; top: 40px; background: var(--bg); border: 1px solid var(--line); display: flex; flex-direction: column; padding: 8px 16px; min-width: 200px; }
  .menu div a { padding: 9px 0; text-decoration: none; }
  .menu div a[aria-current="page"] { color: var(--acc); }

  .hero h1, .hero .facts { grid-column: 1 / -1; }
  .hero .facts { margin-top: 28px; }
  .band .wrap { flex-direction: column; align-items: flex-start; }
  .img-ph, .hero-img img { height: 240px; }

  .sec { padding: 56px 0; }
  .label, .sec .c { grid-column: 1 / -1; }
  .label { margin-bottom: 20px; }
  .format { grid-template-columns: 1fr; }
  ul.people { grid-template-columns: 1fr 1fr; }
  ul.dates { grid-template-columns: 1fr 1fr; }
  ul.spons { grid-template-columns: 1fr 1fr; }
  .programme td.time { width: 124px; }
  .foot { flex-direction: column; }
}