/* =========================================================
   base.css – shared layout for every style.
   Colors and fonts live in the theme files (clean / night /
   editorial), which set the variables below.
   ========================================================= */

:root {
  /* Defaults – each theme overrides these */
  --bg: #ffffff;
  --bg-alt: #f5f5f5;
  --surface: #ffffff;
  --text: #111111;
  --muted: #555555;
  --border: #e5e5e5;
  --accent: #2448d8;
  --accent-text: #ffffff;
  --placeholder-bg: #e9e9e9;
  --placeholder-text: #666666;

  --font-body: system-ui, sans-serif;
  --font-heading: var(--font-body);
  --font-mono: ui-monospace, monospace;

  --radius: 8px;
  --max-width: 1120px;
  --gutter: 24px;
  --section-space: 96px;
}

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 {
  font-family: var(--font-heading);
  line-height: 1.15;
  margin: 0 0 0.5em;
}

p { margin: 0 0 1em; }

a { color: inherit; }

img { max-width: 100%; display: block; }

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

/* ---------- Placeholder boxes ---------- */
.placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 16px;
  background: var(--placeholder-bg);
  color: var(--placeholder-text);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-block;
  padding: 10px 18px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.9rem;
  text-decoration: none;
  cursor: pointer;
  border: 1px solid transparent;
  transition: background 0.2s, color 0.2s, border-color 0.2s;
}
.btn-primary { background: var(--accent); color: var(--accent-text); }
.btn-primary:hover { filter: brightness(1.1); }
.btn-ghost { border-color: var(--border); color: var(--text); }
.btn-ghost:hover { border-color: var(--text); }

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}
.header-inner {
  display: flex;
  align-items: center;
  gap: 24px;
  min-height: 68px;
}
.brand {
  font-family: var(--font-heading);
  font-weight: 700;
  text-decoration: none;
  white-space: nowrap;
}
.main-nav {
  display: flex;
  gap: 20px;
  margin-left: auto;
  font-size: 0.9rem;
}
.main-nav a {
  text-decoration: none;
  color: var(--muted);
  white-space: nowrap;
}
.main-nav a:hover,
.main-nav a[aria-current="page"] { color: var(--text); }

/* CV link */
.cv-link { white-space: nowrap; }

/* ---------- Hero ---------- */
.hero { padding: 80px 0 var(--section-space); }
.hero-inner {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 56px;
  align-items: center;
}
.eyebrow {
  font-size: 0.8rem;
  color: var(--muted);
  letter-spacing: 0.02em;
}
.hero h1 { font-size: clamp(2.6rem, 6vw, 4.5rem); }
.lede { font-size: 1.15rem; color: var(--muted); max-width: 38em; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 28px; }
.hero-visual { aspect-ratio: 4 / 5; border-radius: var(--radius); overflow: hidden; }
.hero-visual img { width: 100%; height: 100%; object-fit: cover; }

/* ---------- Sections ---------- */
.section { padding: var(--section-space) 0; }
.section h2 { font-size: clamp(1.6rem, 3vw, 2.2rem); }
.section-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 32px;
}
.more-link { text-decoration: none; color: var(--accent); font-weight: 600; font-size: 0.9rem; }

/* ---------- Project cards ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 24px;
}
.card {
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform 0.2s, border-color 0.2s;
}
.card:hover { transform: translateY(-3px); border-color: var(--muted); }
.card-image { aspect-ratio: 4 / 3; }
.card-body { padding: 20px; display: flex; flex-direction: column; flex: 1; }
.card-meta { font-size: 0.78rem; color: var(--muted); margin-bottom: 6px; }
.card h3 { font-size: 1.1rem; }
.card h3 a { text-decoration: none; }
.card h3 a:hover { color: var(--accent); }
.card-body > p:not(.card-meta) { font-size: 0.92rem; color: var(--muted); }
.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  list-style: none;
  padding: 0;
  margin: auto 0 0;
}
.tags li {
  font-size: 0.72rem;
  padding: 3px 9px;
  border-radius: 999px;
  background: var(--bg-alt);
  color: var(--muted);
}

/* ---------- Thesis highlight ---------- */
.thesis { background: var(--bg-alt); }
.thesis-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: center;
}
.badge {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
}
.thesis-sub { font-size: 1.1rem; color: var(--muted); font-style: italic; }
.thesis-visual { aspect-ratio: 16 / 10; border-radius: var(--radius); }

/* ---------- Explore by area ---------- */
.area-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 24px;
}
.area {
  display: block;
  padding: 28px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-decoration: none;
  transition: border-color 0.2s;
}
.area:hover { border-color: var(--accent); }
.area-num { font-family: var(--font-mono); font-size: 0.8rem; color: var(--accent); }
.area h3 { margin-top: 12px; font-size: 1.25rem; }
.area p { color: var(--muted); font-size: 0.92rem; margin: 0; }

/* ---------- Footer ---------- */
.site-footer { padding: 72px 0 32px; border-top: 1px solid var(--border); }
.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 40px;
  flex-wrap: wrap;
}
.site-footer h2 { font-size: 1.6rem; }
.site-footer p { color: var(--muted); }
.contact-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.contact-list a { text-decoration: none; }
.contact-list a:hover { color: var(--accent); }
.todo { color: var(--muted); font-style: italic; }
.footer-bottom { margin-top: 56px; font-size: 0.8rem; color: var(--muted); }

/* ---------- Keyboard focus ---------- */
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

/* ---------- Mobile ---------- */
@media (max-width: 860px) {
  :root { --section-space: 64px; --gutter: 16px; }

  .header-inner { flex-wrap: wrap; padding: 12px var(--gutter); gap: 12px; }
  .main-nav {
    order: 3;
    width: 100%;
    margin: 0;
    overflow-x: auto;          /* nav scrolls sideways on small screens */
    padding-bottom: 4px;
  }
  .cv-link { margin-left: auto; }

  .hero { padding-top: 48px; }
  .hero-inner, .thesis-inner { grid-template-columns: 1fr; gap: 32px; }
  .hero-visual { aspect-ratio: 16 / 10; }
  .area-grid { grid-template-columns: 1fr; }
}


/* Respect users who ask for less motion */
@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; scroll-behavior: auto !important; }
}

/* =========================================================
   Projects index page
   ========================================================= */
.page-head { padding: 64px 0 24px; }
.page-head h1 { font-size: clamp(2.2rem, 5vw, 3.2rem); }
.page-head p { color: var(--muted); max-width: 40em; }

.filters { display: flex; flex-wrap: wrap; gap: 8px; margin: 8px 0 32px; }
.filters button {
  font: inherit;
  font-size: 0.85rem;
  padding: 7px 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--muted);
  cursor: pointer;
}
.filters button:hover { color: var(--text); border-color: var(--muted); }
.filters button[aria-pressed="true"] { background: var(--accent); border-color: var(--accent); color: var(--accent-text); }

.card-image img { width: 100%; height: auto; aspect-ratio: 4 / 3; object-fit: cover; display: block; }
.card[hidden] { display: none; }
.card.upcoming { opacity: 0.6; }
.card.upcoming:hover { transform: none; }

/* =========================================================
   Project page (templates/project.html)
   ========================================================= */
.back-link { display: inline-block; margin: 40px 0 0; color: var(--muted); text-decoration: none; font-size: 0.9rem; }
.back-link:hover { color: var(--accent); }

.project-head { padding: 24px 0 40px; }
.project-head h1 { font-size: clamp(2rem, 5vw, 3.2rem); max-width: 18em; }
.project-head .summary { font-size: 1.15rem; color: var(--muted); max-width: 40em; }

/* Small facts row: year, course, tools… */
.facts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 16px 32px;
  margin: 32px 0 0;
  padding: 20px 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.facts dt { font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted); margin-bottom: 4px; }
.facts dd { margin: 0; font-size: 0.95rem; }

/* Long-form text */
.prose { max-width: 720px; padding-bottom: 32px; }
.prose h2 { font-size: 1.5rem; margin-top: 56px; }
.prose p, .prose li { color: var(--text); }
.prose ul { padding-left: 20px; }
.prose li { margin-bottom: 6px; }

/* Figures: plots keep their white background, framed like paper */
.figure { margin: 32px 0; }
.figure img { width: 100%; height: auto; border-radius: var(--radius); }
.figure.plot img { background: #fff; padding: 12px; }
.figure.pixels img { image-rendering: pixelated; }
.figure figcaption { margin-top: 10px; font-size: 0.85rem; color: var(--muted); }

.figure-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 16px; margin: 32px 0; }
.figure-row .figure { margin: 0; }

.wide { max-width: 1000px; }

/* Data tables inside project text */
.data-table { width: 100%; border-collapse: collapse; margin: 24px 0 8px; font-size: 0.92rem; }
.data-table th, .data-table td { text-align: left; padding: 10px 12px 10px 0; border-bottom: 1px solid var(--border); }
.data-table th { font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted); font-weight: 500; }
.table-note { font-size: 0.85rem; color: var(--muted); }

/* Visible "to confirm" notes while content is being checked */
.todo-note {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: #ffcf7a;
  border: 1px dashed #ffcf7a66;
  border-radius: 4px;
  padding: 1px 6px;
}

@media (max-width: 860px) {
  .page-head { padding-top: 40px; }
}

/* =========================================================
   Explainer graphics (used on project pages)
   ========================================================= */

/* Step-by-step pipeline: node → node → node */
.pipeline {
  display: flex;
  align-items: stretch;
  gap: 8px;
  margin: 32px 0;
  overflow-x: auto;
  padding-bottom: 8px;
}
.pipe-node {
  flex: 1 0 150px;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 12px;
  padding: 20px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
}
.pipe-node .visual { height: 96px; display: flex; align-items: center; justify-content: center; }
.pipe-node .visual img { height: 96px; width: 96px; image-rendering: pixelated; border-radius: 6px; }
.pipe-node svg { height: 96px; width: auto; }
.pipe-node strong { font-size: 0.95rem; font-weight: 500; }
.pipe-node span { font-size: 0.8rem; color: var(--muted); }
.pipe-arrow { flex: 0 0 auto; align-self: center; color: var(--accent); font-size: 1.4rem; }

/* A key equation, shown large */
.equation {
  margin: 8px 0 40px;
  max-width: 720px;
  padding: 24px;
  text-align: center;
  font-family: var(--font-mono);
  font-size: clamp(1.1rem, 3vw, 1.5rem);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
}
.equation sub, .equation sup { font-size: 0.65em; }

/* Shared drawing styles for the inline SVGs */
.draw { fill: none; stroke: var(--muted); stroke-width: 1.5; stroke-linecap: round; stroke-linejoin: round; }
.draw .hl { stroke: var(--accent); }
.draw .fill-hl { fill: rgba(var(--accent-rgb), 0.25); stroke: var(--accent); }
.draw .fill-soft { fill: rgba(255, 255, 255, 0.06); }
.draw text { fill: var(--muted); stroke: none; font: 10px var(--font-mono); }
.draw text.hl { fill: var(--accent); }

@media (max-width: 860px) {
  .pipeline { flex-direction: column; overflow: visible; }
  .pipe-node { flex-basis: auto; }
  .pipe-arrow { transform: rotate(90deg); }
}

/* =========================================================
   Text + graphic side by side (e.g. "The physics" + animation)
   ========================================================= */
.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}
.split .prose { padding-bottom: 0; }
.split > * { min-width: 0; }   /* let columns shrink on small screens */
.split + .split { margin-top: 48px; }

/* Binary-star animation (sb2 project page) */
.binary-anim {
  margin: 0;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
}
.binary-anim svg { width: 100%; height: auto; display: block; }
.anim-label { fill: var(--muted); font: 11px var(--font-mono); }
.anim-orbit { fill: none; stroke: var(--border); stroke-width: 1; }
.anim-axis { fill: none; stroke: var(--muted); stroke-width: 1; opacity: 0.5; }
.anim-star1 { fill: #ffd65a; filter: drop-shadow(0 0 6px rgba(255, 214, 90, 0.8)); }
.anim-star2 { fill: #ff9eb5; filter: drop-shadow(0 0 6px rgba(255, 158, 181, 0.8)); }
.anim-dip1, .anim-dip2 { fill: none; stroke-width: 1.5; stroke-dasharray: 4 4; }
.anim-dip1 { stroke: #ffd65a; }
.anim-dip2 { stroke: #ff9eb5; }
.anim-observed { fill: none; stroke: var(--text); stroke-width: 2.5; opacity: 0.85; }

.binary-anim figcaption { margin-top: 10px; font-size: 0.8rem; color: var(--muted); display: flex; flex-wrap: wrap; align-items: center; gap: 6px 10px; }
.key { display: inline-block; width: 18px; height: 0; border-top: 2.5px solid var(--text); vertical-align: middle; }
.key-dips { border-top: 2px dashed #ffd65a; margin-left: 8px; }

@media (max-width: 860px) {
  .split { grid-template-columns: 1fr; gap: 24px; }
}

/* =========================================================
   Animated explainers (NIRPS project page)
   ========================================================= */

/* Framed box around an animation, same look as .binary-anim */
.anim-box {
  margin: 0;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
}
.anim-box svg { width: 100%; height: auto; display: block; }
.anim-box figcaption { margin-top: 10px; font-size: 0.8rem; color: var(--muted); }
.anim-note { font-family: var(--font-mono); font-size: 0.7rem; opacity: 0.8; }

/* Sliders under an animation */
.anim-controls { display: grid; gap: 10px; margin-top: 12px; font-size: 0.8rem; color: var(--muted); }
.anim-controls label { display: grid; grid-template-columns: 13.5em 1fr; align-items: center; gap: 12px; }
.anim-controls input[type="range"] { width: 100%; accent-color: var(--accent); }

/* Shared colours for the drawings */
.c-star { fill: #ffd65a; }
.c-comp { fill: #ff9eb5; }
.l-star { fill: none; stroke: #ffd65a; stroke-width: 2; }
.l-comp { fill: none; stroke: #ff9eb5; stroke-width: 2; }
.l-accent { fill: none; stroke: var(--accent); stroke-width: 2; }
.l-axis { fill: none; stroke: var(--muted); stroke-width: 1; opacity: 0.5; }
.hole { fill: #05060f; stroke: var(--accent); stroke-width: 1.5; stroke-dasharray: 3 3; }
.band { fill: rgba(var(--accent-rgb), 0.12); }

/* Light flowing along a path: moving dashes */
.flow { stroke-dasharray: 6 10; animation: flow 1.1s linear infinite; }
.flow-slow { animation-duration: 2.2s; }
@keyframes flow { to { stroke-dashoffset: -16; } }

/* Step-by-step image viewer (filtering steps) */
.stepper { margin: 32px 0; max-width: 720px; }
.stepper-frames {
  position: relative;
  aspect-ratio: 600 / 394;
  border-radius: var(--radius);
  overflow: hidden;
  background: #000;
}
.stepper-frames img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  transition: opacity 0.6s;
}
.stepper-frames img.is-active { opacity: 1; }
.stepper-buttons { display: flex; flex-wrap: wrap; gap: 8px; margin: 14px 0 8px; }
.stepper-buttons button {
  font: inherit;
  font-size: 0.8rem;
  padding: 6px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--muted);
  cursor: pointer;
}
.stepper-buttons button:hover { color: var(--text); border-color: var(--muted); }
.stepper-buttons button[aria-pressed="true"] { background: var(--accent); border-color: var(--accent); color: var(--accent-text); }
.stepper-caption { font-size: 0.9rem; color: var(--muted); min-height: 3em; }

/* One-line takeaway */
.takeaway {
  max-width: 720px;
  margin: 8px 0 32px;
  padding: 18px 22px;
  border-left: 3px solid var(--accent);
  background: var(--surface);
  border-radius: 0 var(--radius) var(--radius) 0;
  font-size: 1.1rem;
}

/* Download links */
.file-list { list-style: none; padding: 0; display: grid; gap: 10px; }
.file-list a { color: var(--accent); }

@media (prefers-reduced-motion: reduce) {
  .flow { animation: none; }
  .stepper-frames img { transition: none; }
}

/* =========================================================
   ExoClock page: transit animation and "how to take part" steps
   ========================================================= */
.t-planet { fill: #05060f; stroke: var(--muted); stroke-width: 1; }
.t-dot { fill: var(--accent); }

.steps-title { font-size: 1.5rem; margin-top: 56px; }
.steps-intro { max-width: 720px; color: var(--muted); margin-bottom: 32px; }
.steps-intro a { color: var(--accent); }
.steps {
  list-style: none;
  counter-reset: step;
  padding: 0;
  margin: 24px 0 32px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 12px;
}
.steps li {
  counter-increment: step;
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 20px 18px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
}
.steps li::before {
  content: "0" counter(step);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent);
}
.steps strong { font-weight: 500; }
.steps span { font-size: 0.88rem; color: var(--muted); }
.steps a { color: var(--accent); }

/* Title with a logo on the right (ExoClock page) */
.head-with-logo { display: grid; grid-template-columns: 1fr auto; gap: 32px; align-items: center; }
.head-logo { width: 160px; height: auto; }

/* Card showing a logo: keep the whole logo visible instead of cropping */
.card-logo { display: flex; align-items: center; justify-content: center; background: var(--surface); }
.card-logo img { width: 55%; height: auto; aspect-ratio: auto; object-fit: contain; }

@media (max-width: 860px) {
  .head-with-logo { grid-template-columns: 1fr; gap: 16px; }
  .head-with-logo > a { order: -1; }
  .head-logo { width: 96px; }
}

/* =========================================================
   Science Outreach pages (outreach/)
   ========================================================= */

/* Large horizontal card: photo on the left, text on the right */
.video-embed { aspect-ratio: 16 / 9; border-radius: var(--radius); overflow: hidden; background: #000; }
.video-embed iframe { display: block; width: 100%; height: 100%; border: 0; }

.feature-card {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color 0.2s;
}
.feature-card:hover { border-color: var(--warm); }
.feature-card img { width: 100%; height: 100%; object-fit: cover; }
.feature-card .card-body { padding: 32px; justify-content: center; }
.feature-card h2 { font-size: clamp(1.4rem, 3vw, 1.9rem); }
.feature-card h2 a { text-decoration: none; }
.feature-card h2 a:hover { color: var(--warm); }

.outreach-list { display: grid; gap: 24px; margin-bottom: 32px; }
.outreach-list .card-image.placeholder { aspect-ratio: auto; min-height: 220px; }
.feature-card.upcoming { opacity: 0.6; }
.feature-card.upcoming:hover { border-color: var(--border); }

.outreach-more { padding-bottom: 64px; }
.outreach-more p { color: var(--muted); max-width: 40em; }

/* Row of portrait photos with captions */
.photo-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
  margin: 32px 0;
}
.photo-row .figure { margin: 0; }
.photo-row img { aspect-ratio: 3 / 4; object-fit: cover; }

/* Lead photo: not full width, because the source photos are small */
.figure.cover { max-width: 900px; }
.figure.cover img { aspect-ratio: 16 / 9; object-fit: cover; }

/* Side-by-side text + photo on outreach pages */
.split.photo-split { grid-template-columns: 1.3fr 1fr; align-items: start; margin: 56px 0 0; }
.split.photo-split .figure { margin: 0; }
.split.photo-split .prose h2:first-child { margin-top: 0; }

/* Short quoted passage (e.g. from the tour script) */
.excerpt {
  max-width: 720px;
  margin: 24px 0;
  padding: 18px 22px;
  border-left: 3px solid var(--warm);
  background: var(--surface);
  border-radius: 0 var(--radius) var(--radius) 0;
}
.excerpt p { margin: 0 0 0.6em; font-style: italic; }
.excerpt footer { font-size: 0.8rem; color: var(--muted); font-style: normal; }

@media (max-width: 860px) {
  .feature-card, .split.photo-split { grid-template-columns: 1fr; }
  .feature-card img { aspect-ratio: 16 / 10; }
  .feature-card .card-body { padding: 24px 20px; }
}

/* Contact page */
.contact-page { min-height: 50vh; padding-bottom: 80px; }
.contact-details h2 { font-size: 1rem; color: var(--muted); font-weight: 400; }
.contact-email { font-size: clamp(1rem, 2vw, 1.3rem); color: var(--accent); overflow-wrap: anywhere; text-underline-offset: 5px; }