/* The Science of Stuff — theme styles. Tokens + components from the brand's
   _ds industry system; layout added for a real, responsive publisher site. */

:root {
  --color-bg: #f2f2f3;
  --color-surface: #e9e9ea;
  --color-text: #1d1f20;
  --color-accent: #5980a6;
  --color-divider: color-mix(in srgb, #1d1f20 16%, transparent);

  --color-neutral-400: #b7b7ba;
  --color-neutral-500: #98989b;
  --color-neutral-700: #5d5d60;
  --color-neutral-800: #424244;

  --color-accent-600: #597ea3;
  --color-accent-700: #416180;
  --color-accent-900: #1d2d3d;

  --font-heading: "Barlow Condensed", system-ui, sans-serif;
  --font-body: "Barlow", system-ui, sans-serif;

  --wrap: 1120px;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--color-bg); color: var(--color-text);
  font-family: var(--font-body); font-size: 17px; line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; height: auto; }
a { color: var(--color-accent-700); text-underline-offset: 3px; }
a:hover { color: var(--color-accent-900); }
:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }
::selection { background: color-mix(in srgb, var(--color-accent) 30%, transparent); }
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 24px; }

/* headings */
h1, h2, h3, h4 { font-family: var(--font-heading); font-weight: 600; line-height: 1.05; letter-spacing: -0.02em; margin: 0; }

/* kicker / label */
.kicker { font-family: var(--font-heading); font-size: 11px; letter-spacing: 0.16em; text-transform: uppercase; color: var(--color-accent-700); }
.label-muted { font-family: var(--font-heading); font-size: 11px; letter-spacing: 0.16em; text-transform: uppercase; color: var(--color-neutral-700); }

/* ── Masthead ─────────────────────────────────────────────────────────── */
.masthead { background: var(--color-accent-900); color: #f2f2f3; }
.masthead-inner { display: flex; align-items: center; gap: 20px; padding: 15px 24px; max-width: var(--wrap); margin: 0 auto; }
.masthead-brand { font-family: var(--font-heading); font-weight: 700; font-size: 21px; text-transform: uppercase; letter-spacing: -0.01em; color: #f2f2f3; text-decoration: none; margin-right: auto; }
.masthead-nav { display: flex; gap: 22px; font-family: var(--font-heading); font-size: 14px; letter-spacing: 0.08em; text-transform: uppercase; }
.masthead-nav a { color: #f2f2f3; opacity: 0.88; text-decoration: none; }
.masthead-nav a:hover { opacity: 1; color: #f2f2f3; }
.masthead-cta { font-family: var(--font-heading); font-size: 13px; letter-spacing: 0.1em; text-transform: uppercase; color: var(--color-accent-900); background: #f2f2f3; padding: 7px 14px; text-decoration: none; white-space: nowrap; }
.masthead-cta:hover { color: var(--color-accent-900); }
.masthead-search { display: inline-flex; align-items: center; background: none; border: 0; color: #f2f2f3; opacity: 0.85; cursor: pointer; padding: 4px; }
.masthead-search:hover { opacity: 1; }
.nav-toggle { display: none; }

/* footer nav */
.site-footer-nav { display: flex; gap: 20px; }
.site-footer-nav a { color: var(--color-neutral-700); text-decoration: none; font-family: var(--font-heading); text-transform: uppercase; letter-spacing: 0.08em; font-size: 13px; }
.site-footer-nav a:hover { color: var(--color-accent-700); }

/* tag / category landing header */
.tag-header { margin: 48px 0 8px; border-bottom: 2px solid var(--color-text); padding-bottom: 16px; }
.tag-header h1 { font-size: 56px; line-height: 0.94; margin: 6px 0 0; }
.tag-desc { font-size: 18px; line-height: 1.45; color: var(--color-neutral-800); max-width: 60ch; margin: 14px 0 0; }
.tag-count { margin: 18px 0 24px; }
.tag-empty { font-size: 18px; color: var(--color-neutral-800); margin: 0 0 48px; }

/* A–Z Index */
.index-list { border-top: 1px solid var(--color-divider); margin-bottom: 48px; }
.index-row { display: flex; align-items: baseline; justify-content: space-between; gap: 20px; padding: 16px 0; border-bottom: 1px solid var(--color-divider); text-decoration: none; color: var(--color-text); }
.index-row:hover .index-title { color: var(--color-accent-700); }
.index-title { font-family: var(--font-heading); font-weight: 600; font-size: 22px; line-height: 1.1; }
.index-meta { display: inline-flex; align-items: center; gap: 12px; flex: none; }
.index-topic { font-family: var(--font-heading); font-size: 11px; letter-spacing: 0.16em; text-transform: uppercase; color: var(--color-neutral-700); }
.grade-badge { font-family: var(--font-heading); font-size: 11px; letter-spacing: 0.14em; text-transform: uppercase; color: var(--color-accent-900); background: var(--color-accent-200); padding: 3px 10px; white-space: nowrap; }
@media (max-width: 640px) {
  .index-row { flex-direction: column; gap: 8px; }
  .tag-header h1 { font-size: 40px; }
}

/* ── Home hero ────────────────────────────────────────────────────────── */
.hero { border: 1px solid var(--color-divider); background: var(--color-bg); margin-top: 40px; }
.hero-grid { display: grid; grid-template-columns: 1.15fr 1fr; }
.hero-body { padding: 40px 32px 36px; border-right: 1px solid var(--color-divider); }
.hero-meta { display: inline-flex; align-items: center; gap: 10px; margin-bottom: 18px; }
.hero-meta .dash { width: 24px; height: 1px; background: var(--color-neutral-400); }
.hero h1 { font-size: 52px; line-height: 0.96; margin: 0 0 16px; }
.hero .standfirst { font-size: 17px; line-height: 1.6; color: var(--color-neutral-800); max-width: 46ch; margin: 0 0 20px; }
.byline { display: flex; gap: 12px; align-items: center; font-size: 13px; color: var(--color-neutral-700); }
.byline .dot { width: 3px; height: 3px; background: var(--color-neutral-500); }
.hero-figure { position: relative; min-height: 320px; overflow: hidden; }
.hero-figure img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; }

/* duotone wash on photography */
.duotone { position: relative; overflow: hidden; }
.duotone::after { content: ""; position: absolute; inset: 0; pointer-events: none; background: var(--color-accent); mix-blend-mode: color; }

/* ── Post grid ────────────────────────────────────────────────────────── */
.section-rule { display: flex; align-items: baseline; gap: 16px; border-bottom: 2px solid var(--color-text); padding-bottom: 10px; margin: 64px 0 28px; }
.section-rule h2 { font-size: 26px; text-transform: uppercase; letter-spacing: 0.02em; }
.card-grid { display: grid; grid-template-columns: repeat(3, 1fr); border: 1px solid var(--color-divider); border-bottom: 0; }
.post-card { padding: 28px 24px 30px; border-right: 1px solid var(--color-divider); border-bottom: 1px solid var(--color-divider); display: flex; flex-direction: column; }
.post-card:nth-child(3n) { border-right: 0; }
.post-card-figure { height: 150px; margin-bottom: 18px; border: 1px solid var(--color-divider); position: relative; overflow: hidden; background: var(--color-surface); }
.post-card-figure img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; }
.post-card .kicker { margin-bottom: 8px; }
.post-card h3 { font-size: 25px; line-height: 1.05; margin: 0 0 8px; }
.post-card p { margin: 0; font-size: 15px; color: var(--color-neutral-800); }
.post-card a { color: inherit; text-decoration: none; }
.post-card a:hover h3 { color: var(--color-accent-700); }

/* ── Evidence bar (the signature device) ──────────────────────────────── */
.evidence-bar { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 2px solid var(--color-text); border-bottom: 1px solid var(--color-divider); margin: 24px 0 30px; }
.evidence-cell { padding: 12px 0; }
.evidence-cell .k { font-family: var(--font-heading); font-size: 10px; letter-spacing: 0.16em; text-transform: uppercase; color: var(--color-neutral-700); }
.evidence-cell .v { font-family: var(--font-heading); font-size: 19px; text-transform: uppercase; }

/* inline evidence tag (kicker area, cards) */
.grade { font-family: var(--font-heading); font-size: 11px; letter-spacing: 0.16em; text-transform: uppercase; color: var(--color-neutral-700); }

/* ── Article ──────────────────────────────────────────────────────────── */
.article { max-width: 720px; margin: 40px auto 0; padding: 0 24px; }
.article-header { margin-bottom: 26px; }
.article-header .kicker { margin-bottom: 16px; display: block; }
.article h1 { font-size: 54px; line-height: 0.95; margin: 0 0 18px; }
.article .standfirst { font-size: 20px; line-height: 1.45; color: var(--color-neutral-800); margin: 0 0 8px; }
.reviewed-by { font-family: var(--font-heading); font-size: 12px; letter-spacing: 0.12em; text-transform: uppercase; color: var(--color-accent-700); margin: 14px 0 0; }
.article-feature { margin: 0 0 30px; border: 1px solid var(--color-divider); position: relative; overflow: hidden; }

/* prose — Ghost renders post body into .gh-content */
.gh-content { font-size: 17px; line-height: 1.68; }
.gh-content > * + * { margin-top: 20px; }
.gh-content h2 { font-size: 32px; margin-top: 40px; }
.gh-content h3 { font-size: 24px; margin-top: 32px; }
.gh-content a { color: var(--color-accent-700); }
.gh-content img { margin: 28px 0; border: 1px solid var(--color-divider); }
.gh-content figcaption { font-size: 13px; color: var(--color-neutral-700); margin-top: 6px; text-align: center; }
.gh-content blockquote { margin: 8px 0; padding-left: 22px; border-left: 3px solid var(--color-accent); font-family: var(--font-heading); font-weight: 500; font-size: 27px; line-height: 1.2; }
.gh-content ul, .gh-content ol { padding-left: 22px; }
.gh-content li + li { margin-top: 8px; }
.gh-content hr { border: 0; border-top: 1px solid var(--color-divider); margin: 32px 0; }

/* Koenig editor card widths (required by Ghost) */
.gh-content .kg-width-wide { position: relative; width: min(100vw, 1080px); left: 50%; transform: translateX(-50%); max-width: none; }
.gh-content .kg-width-full { position: relative; width: 100vw; left: 50%; transform: translateX(-50%); max-width: none; }
.gh-content .kg-width-full img { width: 100%; }
.gh-content figure { margin: 28px 0; }
.gh-content .kg-image-card img { margin: 0; }

/* ── Newsletter / subscribe block ─────────────────────────────────────── */
.subscribe { border: 1px solid var(--color-divider); margin: 64px auto 0; max-width: 560px; }
.subscribe-head { background: var(--color-accent-900); color: #f2f2f3; padding: 26px; }
.subscribe-head .mark { font-family: var(--font-heading); font-weight: 700; font-size: 26px; line-height: 0.86; text-transform: uppercase; }
.subscribe-body { padding: 24px 26px 28px; }
.subscribe form { display: flex; gap: 8px; }
.input { flex: 1; min-width: 0; min-height: 40px; padding: 6px 12px; font: inherit; font-size: 15px; color: var(--color-text); background: var(--color-surface); border: 1px solid var(--color-divider); border-radius: 0; }
.input:focus-visible { border-color: var(--color-accent); outline-offset: 0; }
.btn-primary { font-family: var(--font-heading); font-weight: 600; font-size: 15px; text-transform: uppercase; letter-spacing: 0.06em; padding: 8px 18px; background: var(--color-accent); color: var(--color-bg); border: 1px solid var(--color-accent); border-radius: 0; cursor: pointer; }
.btn-primary:hover { background: var(--color-accent-600); }
.fine { margin: 14px 0 0; font-size: 12px; color: var(--color-neutral-700); }

/* ── Footer ───────────────────────────────────────────────────────────── */
.site-footer { margin-top: 96px; border-top: 2px solid var(--color-text); }
.site-footer-inner { max-width: var(--wrap); margin: 0 auto; padding: 28px 24px 60px; display: flex; flex-wrap: wrap; gap: 16px; justify-content: space-between; align-items: baseline; font-size: 13px; color: var(--color-neutral-700); }
.site-footer .mark { font-family: var(--font-heading); font-weight: 700; font-size: 18px; text-transform: uppercase; color: var(--color-text); text-decoration: none; }

/* pagination */
.pagination { display: flex; justify-content: center; gap: 20px; margin: 40px 0; font-family: var(--font-heading); text-transform: uppercase; letter-spacing: 0.08em; font-size: 14px; }

/* ── Email-capture pop-up (submits to Ghost native members form) ────────── */
.sos-popup-overlay { position: fixed; inset: 0; z-index: 1000; display: none; align-items: center; justify-content: center; padding: 20px; background: color-mix(in srgb, var(--color-accent-900) 60%, transparent); }
.sos-popup-overlay.open { display: flex; }
.sos-popup { position: relative; width: 100%; max-width: 460px; background: var(--color-bg); border: 1px solid var(--color-divider); box-shadow: var(--shadow-lg, 0 12px 32px rgba(43,43,45,0.22)); }
.sos-popup-close { position: absolute; top: 8px; right: 12px; z-index: 1; background: none; border: 0; color: #f2f2f3; font-size: 26px; line-height: 1; cursor: pointer; opacity: 0.8; }
.sos-popup-close:hover { opacity: 1; }
.sos-popup-head { background: var(--color-accent-900); color: #f2f2f3; padding: 24px 26px; }
.sos-popup-head .mark { font-family: var(--font-heading); font-weight: 700; font-size: 24px; line-height: 0.86; text-transform: uppercase; }
.sos-popup-body { padding: 22px 26px 26px; }
.sos-popup h3 { font-size: 25px; margin: 0 0 8px; }
.sos-popup p.pitch { margin: 0 0 16px; font-size: 15px; color: var(--color-neutral-800); }
.sos-popup-fields { display: flex; gap: 8px; }
.sos-popup .form-message { display: none; margin: 12px 0 0; font-size: 14px; }
.sos-popup form.success .sos-popup-fields { display: none; }
.sos-popup form.success .success-message { display: block; color: var(--color-accent-700); }
.sos-popup form.error .error-message { display: block; color: #b3352e; }
.sos-popup .fine { margin: 12px 0 0; font-size: 12px; color: var(--color-neutral-700); }

/* ── Inline signup band (inside articles; Ghost native form) ────────────── */
.signup-inline { margin: 36px 0; padding: 24px 26px; background: var(--color-accent-100); border: 1px solid var(--color-divider); border-left: 3px solid var(--color-accent); }
.signup-inline-text { margin-bottom: 14px; }
.signup-inline-text strong { display: block; font-family: var(--font-heading); font-weight: 600; font-size: 22px; letter-spacing: -0.01em; }
.signup-inline-text span { font-size: 15px; color: var(--color-neutral-800); }
.signup-inline-fields { display: flex; gap: 8px; }
.signup-inline .input { flex: 1; min-width: 0; }
.signup-inline .form-message { display: none; margin: 10px 0 0; font-size: 14px; }
.signup-inline form.success .signup-inline-fields { display: none; }
.signup-inline form.success .success-message { display: block; color: var(--color-accent-700); }
.signup-inline form.error .error-message { display: block; color: #b3352e; }

/* ── Responsive ───────────────────────────────────────────────────────── */
@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-body { border-right: 0; border-bottom: 1px solid var(--color-divider); }
  .hero h1 { font-size: 40px; }
  .hero-figure { min-height: 220px; }
  .card-grid { grid-template-columns: 1fr 1fr; }
  .post-card:nth-child(3n) { border-right: 1px solid var(--color-divider); }
  .post-card:nth-child(2n) { border-right: 0; }
}
@media (max-width: 640px) {
  body { font-size: 16px; }
  .masthead-nav { display: none; }
  .nav-toggle { display: inline-block; margin-left: auto; margin-right: 14px; background: none; border: 0; color: #f2f2f3; font-family: var(--font-heading); text-transform: uppercase; letter-spacing: 0.1em; font-size: 13px; cursor: pointer; }
  .masthead-nav.open { display: flex; flex-direction: column; gap: 12px; width: 100%; padding: 0 24px 16px; }
  .card-grid { grid-template-columns: 1fr; }
  .post-card, .post-card:nth-child(3n) { border-right: 0; }
  .article h1 { font-size: 38px; }
  .gh-content blockquote { font-size: 22px; }
}