/* Colours are taken from the portraits themselves: the warm paper, the
   dark ink, the violet-to-cyan X-ray streak, the red laser streak, the
   green electron beads (MeV-UED only) and the gold ribbon that joins the
   science half of each painting to its everyday half. */
:root {
  --paper: #f1e8d6;
  --paper-light: #f8f2e6;
  --paper-dark: #e4d7bd;
  --ink: #1c2226;
  --ink-soft: #4a4f52;
  --teal: #1d5c73;
  --xray-violet: #4b1d8f;
  --xray-cyan: #2fb8d6;
  --laser-red: #e24a2b;
  --electron-green: #22b14c;
  --ribbon-gold: #f2c14e;
  --ribbon-gold-dark: #b8791b;

  --display-font: "Fraunces", Georgia, serif;
  --body-font: "Source Serif 4", Georgia, serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background-color: var(--paper);
  color: var(--ink);
  font-family: var(--body-font);
  font-size: 1.08rem;
  line-height: 1.6;
}

a {
  color: var(--teal);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

a:hover {
  color: var(--xray-violet);
}

.page {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- Header ---------- */

.site-header {
  padding: 72px 0 32px;
  text-align: center;
}

.eyebrow {
  margin: 0 0 12px;
  font-size: 0.85rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.site-header h1 {
  margin: 0;
  font-family: var(--display-font);
  font-weight: 600;
  font-size: clamp(2.4rem, 6vw, 4.2rem);
  line-height: 1.05;
  letter-spacing: -0.01em;
}

/* A painted-looking X-ray streak under the title. */
.xray-streak {
  width: min(420px, 70%);
  height: 6px;
  margin: 28px auto;
  border-radius: 3px;
  background: linear-gradient(90deg, var(--xray-violet) 0%, var(--xray-violet) 55%, var(--xray-cyan) 100%);
  box-shadow: 0 0 12px rgba(47, 184, 214, 0.45);
}

.intro {
  max-width: 640px;
  margin: 0 auto;
  font-size: 1.2rem;
  color: var(--ink-soft);
}

/* ---------- How to read a portrait ---------- */

.how-to-read {
  margin: 40px auto 0;
  padding: 28px 32px;
  max-width: 880px;
  background: var(--paper-light);
  border: 1px solid var(--paper-dark);
  border-radius: 6px;
}

.how-to-read h2 {
  margin: 0 0 16px;
  font-family: var(--display-font);
  font-weight: 600;
  font-size: 1.35rem;
  text-align: center;
}

.legend {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px 36px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 0.98rem;
  text-align: left;
}

.legend li {
  display: flex;
  gap: 12px;
  align-items: flex-start;
}

.swatch {
  flex: none;
  width: 44px;
  height: 22px;
  margin-top: 3px;
  border-radius: 3px;
}

.swatch-halves {
  background: linear-gradient(180deg, #dce6ea 0%, #dce6ea 55%, #f6dfa6 55%, #f6dfa6 100%);
  border: 1px solid var(--ink-soft);
}

.swatch-xray {
  height: 5px;
  margin-top: 11px;
  background: linear-gradient(90deg, var(--xray-violet) 55%, var(--xray-cyan));
}

.swatch-laser {
  height: 7px;
  margin-top: 10px;
  background: var(--laser-red);
}

.swatch-electron {
  height: 10px;
  margin-top: 9px;
  background: radial-gradient(circle, var(--electron-green) 0 4px, transparent 4.5px) 0 0 / 11px 10px repeat-x;
}

.swatch-ribbon {
  background: var(--ribbon-gold);
  border: 1px solid var(--ribbon-gold-dark);
  clip-path: polygon(0 0, 100% 0, 100% 60%, 50% 100%, 0 60%);
}

/* ---------- Thumbnail index ---------- */

.index {
  display: grid;
  grid-template-columns: repeat(10, minmax(0, 1fr));
  gap: 12px;
  margin: 48px 0 24px;
  padding: 0;
  list-style: none;
}

.index a {
  display: block;
  text-align: center;
  text-decoration: none;
  color: var(--ink);
  font-weight: 600;
  font-size: 0.9rem;
  letter-spacing: 0.04em;
}

.index img {
  display: block;
  width: 100%;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  margin-bottom: 6px;
  border: 4px solid var(--paper-light);
  box-shadow: 0 2px 8px rgba(28, 34, 38, 0.18);
  transition: transform 0.15s ease;
}

.index a:hover img {
  transform: translateY(-4px);
}

/* ---------- One plate per instrument ---------- */

.plate {
  display: grid;
  grid-template-columns: 5fr 6fr;
  gap: 56px;
  align-items: center;
  margin: 0;
  padding: 72px 0;
  border-top: 1px solid var(--paper-dark);
  scroll-margin-top: 16px;
}

/* Alternate the side the painting sits on, like pages in a book. */
.plate:nth-of-type(even) {
  grid-template-columns: 6fr 5fr;
}

.plate:nth-of-type(even) .plate-image {
  order: 2;
}

.plate-image {
  display: block;
  padding: 12px;
  background: var(--paper-light);
  box-shadow: 0 4px 18px rgba(28, 34, 38, 0.2);
}

.plate-image img {
  display: block;
  width: 100%;
  height: auto;
}

.plate figcaption {
  font-size: 1.04rem;
}

.acronym {
  margin: 0;
  font-family: var(--display-font);
  font-weight: 700;
  font-size: 3rem;
  line-height: 1;
  color: var(--teal);
}

.full-name {
  margin: 6px 0 0;
  font-size: 0.85rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.metaphor {
  margin: 18px 0 22px;
  font-family: var(--display-font);
  font-style: italic;
  font-weight: 400;
  font-size: 1.45rem;
  line-height: 1.3;
}

.caption-part {
  margin: 0 0 16px;
  padding-left: 16px;
  border-left: 4px solid var(--paper-dark);
}

.caption-part h3 {
  margin: 0 0 2px;
  font-family: var(--body-font);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.caption-part p {
  margin: 0;
}

.caption-part.science {
  border-left-color: var(--xray-violet);
}

/* MeV-UED probes with electrons, not X-rays. */
#ued .caption-part.science {
  border-left-color: var(--electron-green);
}

.caption-part.everyday {
  border-left-color: var(--ribbon-gold);
}

.plate-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
  font-size: 0.95rem;
}

/* ---------- Footer ---------- */

.site-footer {
  padding: 48px 0 72px;
  border-top: 1px solid var(--paper-dark);
  font-size: 0.95rem;
  color: var(--ink-soft);
}

.site-footer p {
  max-width: 760px;
  margin: 0 0 12px;
}

/* ---------- Small screens ---------- */

@media (max-width: 860px) {
  .index {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .index a {
    font-size: 0.72rem;
    white-space: nowrap;
  }

  .legend {
    grid-template-columns: 1fr;
  }

  .plate,
  .plate:nth-of-type(even) {
    grid-template-columns: 1fr;
    gap: 28px;
    padding: 48px 0;
  }

  .plate:nth-of-type(even) .plate-image {
    order: 0;
  }

  .plate-image {
    max-width: 480px;
    margin: 0 auto;
  }
}