/* =====================================================================
   RTIJTI DESIGN SYSTEM
   Signature idea: "waypoints" — a road/circuit trace motif that threads
   through breadcrumbs, the editorial workflow, and the hero, tying the
   RTIJTI name to the journal's academic through-line: submission →
   review → publication → citation.
   ===================================================================== */

:root {
  /* Color */
  --ink:        #10192E;   /* primary dark — nav, footer, headings */
  --ink-soft:   #1B2942;
  --paper:      #F7F7F3;   /* page background, cool warm-neutral (not cliché cream) */
  --surface:    #FFFFFF;
  --border:     #E3E3DC;
  --border-soft:#EDEDE6;
  --text:       #172033;
  --text-soft:  #57657A;
  --text-faint: #8891A0;
  --amber:      #E2963A;   /* signal / CTA accent */
  --amber-dark: #C67C24;
  --teal:       #1E7268;   /* circuit accent — links, subject tags */
  --teal-dark:  #145A52;
  --red:        #B94A3D;

  /* Type */
  --font-display: 'Fraunces', Georgia, serif;
  --font-body:    'Source Serif 4', Georgia, serif;
  --font-ui:      'IBM Plex Sans', -apple-system, Segoe UI, sans-serif;
  --font-mono:    'IBM Plex Mono', monospace;

  --radius: 10px;
  --radius-sm: 6px;
  --shadow-sm: 0 1px 2px rgba(16,25,46,0.06);
  --shadow-md: 0 6px 20px rgba(16,25,46,0.08);
  --shadow-lg: 0 16px 40px rgba(16,25,46,0.14);

  --container: 1180px;
}

@media (prefers-color-scheme: dark) {
  :root.auto-dark {
    --ink: #F7F7F3; --paper: #0D1220; --surface: #141B2C; --border: #263049;
    --border-soft: #1E2740; --text: #EDEFF5; --text-soft: #A6B0C3; --text-faint: #6E7A90;
  }
}
html.dark {
  --ink: #F7F7F3; --paper: #0B0F1A; --surface: #131A2B; --border: #232D46;
  --border-soft: #1B2338; --text: #ECEEF4; --text-soft: #9FA9BE; --text-faint: #6C7891;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--text);
  font-family: var(--font-ui);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: var(--teal-dark); text-decoration: none; }
a:hover { text-decoration: underline; }
html.dark a { color: #5FCBBE; }

h1, h2, h3, h4 {
  font-family: var(--font-display);
  color: var(--ink);
  line-height: 1.15;
  margin: 0 0 0.5em;
  font-weight: 600;
}
h1 { font-size: clamp(2rem, 4vw, 3.1rem); font-weight: 500; }
h2 { font-size: clamp(1.5rem, 2.6vw, 2.1rem); }
h3 { font-size: 1.3rem; }
p { margin: 0 0 1em; }
.lede { font-family: var(--font-body); font-size: 1.15rem; color: var(--text-soft); }

.container { max-width: var(--container); margin: 0 auto; padding: 0 24px; }
.container-narrow { max-width: 860px; margin: 0 auto; padding: 0 24px; }
section { padding: 64px 0; }
.section-tight { padding: 40px 0; }

.eyebrow {
  font-family: var(--font-ui);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--amber-dark);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
}
.eyebrow::before {
  content: '';
  width: 18px; height: 2px;
  background: var(--amber);
  display: inline-block;
}

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  font-family: var(--font-ui); font-weight: 600; font-size: 0.92rem;
  padding: 12px 22px; border-radius: 999px; border: 1px solid transparent;
  cursor: pointer; transition: transform .15s ease, box-shadow .15s ease, background .15s ease;
  text-decoration: none;
}
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--ink); color: #fff; }
.btn-primary:hover { background: var(--ink-soft); box-shadow: var(--shadow-md); transform: translateY(-1px); }
.btn-amber { background: var(--amber); color: var(--ink); }
.btn-amber:hover { background: var(--amber-dark); color: #fff; transform: translateY(-1px); }
.btn-outline { background: transparent; color: var(--ink); border-color: var(--border); }
html.dark .btn-outline { color: var(--text); }
.btn-outline:hover { border-color: var(--ink); background: var(--surface); }
.btn-sm { padding: 8px 16px; font-size: 0.82rem; }
.btn-block { width: 100%; }

/* Top utility bar + nav */
.topbar {
  background: var(--ink); color: #c9d2e3; font-size: 0.78rem; font-family: var(--font-ui);
}
.topbar .container { display: flex; justify-content: space-between; align-items: center; padding-top: 7px; padding-bottom: 7px; flex-wrap: wrap; gap: 6px; }
.topbar a { color: #c9d2e3; }
.topbar .topbar-links { display: flex; gap: 16px; flex-wrap: wrap; }
.topbar .topbar-links span, .topbar .topbar-links a { display: inline-flex; align-items: center; gap: 5px; }

header.site-header {
  background: var(--surface); border-bottom: 1px solid var(--border);
  position: sticky; top: 0; z-index: 40;
}
.header-inner { display: flex; align-items: center; justify-content: space-between; padding: 14px 0; gap: 20px; }
.brand { display: flex; align-items: center; gap: 12px; text-decoration: none; }
.brand:hover { text-decoration: none; }
.brand-mark {
  width: 44px; height: 44px; border-radius: 10px; flex-shrink: 0;
  background: linear-gradient(135deg, var(--ink) 0%, var(--teal-dark) 100%);
  display: flex; align-items: center; justify-content: center;
  color: #fff; font-family: var(--font-display); font-weight: 700; font-size: 1.1rem;
}
.brand-text { line-height: 1.15; }
.brand-text .name { font-family: var(--font-display); font-weight: 600; font-size: 1.08rem; color: var(--ink); display: block; }
.brand-text .short { font-family: var(--font-ui); font-size: 0.72rem; letter-spacing: 0.08em; color: var(--text-soft); text-transform: uppercase; }

nav.main-nav { display: flex; align-items: center; gap: 2px; flex-wrap: wrap; }
nav.main-nav > .nav-item { position: relative; }
nav.main-nav a.nav-link {
  font-family: var(--font-ui); font-size: 0.88rem; font-weight: 500; color: var(--text);
  padding: 10px 12px; border-radius: 6px; display: inline-block;
}
nav.main-nav a.nav-link:hover { background: var(--border-soft); text-decoration: none; }
.nav-dropdown {
  display: none; position: absolute; top: 100%; left: 0; background: var(--surface);
  border: 1px solid var(--border); border-radius: var(--radius-sm); box-shadow: var(--shadow-md);
  min-width: 240px; padding: 8px; z-index: 50;
}
.nav-item:hover .nav-dropdown { display: block; }
.nav-dropdown a { display: block; padding: 8px 10px; border-radius: 6px; font-size: 0.86rem; color: var(--text); }
.nav-dropdown a:hover { background: var(--border-soft); text-decoration: none; }
.header-actions { display: flex; align-items: center; gap: 10px; }
.icon-btn {
  width: 36px; height: 36px; border-radius: 50%; border: 1px solid var(--border);
  background: var(--surface); display: flex; align-items: center; justify-content: center;
  cursor: pointer; color: var(--text);
}
.icon-btn:hover { background: var(--border-soft); }
.mobile-toggle { display: none; }

@media (max-width: 980px) {
  nav.main-nav { display: none; }
  .mobile-toggle { display: flex; }
}

/* Cards */
.card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 22px; transition: box-shadow .15s ease, transform .15s ease;
}
.card:hover { box-shadow: var(--shadow-md); }
.card-flat { border-radius: var(--radius); }

.tag {
  display: inline-block; font-family: var(--font-ui); font-size: 0.72rem; font-weight: 600;
  padding: 4px 10px; border-radius: 999px; background: rgba(30,114,104,0.1); color: var(--teal-dark);
  letter-spacing: 0.02em;
}
html.dark .tag { background: rgba(95,203,190,0.14); color: #7fe0d3; }
.tag-amber { background: rgba(226,150,58,0.14); color: var(--amber-dark); }

/* Waypoint / path signature motif */
.waypoints { display: flex; align-items: center; gap: 0; flex-wrap: wrap; }
.waypoint { display: flex; align-items: center; gap: 10px; }
.waypoint .dot {
  width: 10px; height: 10px; border-radius: 50%; background: var(--amber); flex-shrink: 0;
  box-shadow: 0 0 0 4px rgba(226,150,58,0.15);
}
.waypoint.done .dot { background: var(--teal); box-shadow: 0 0 0 4px rgba(30,114,104,0.15); }
.waypoint .line { width: 46px; height: 2px; background: var(--border); margin: 0 6px; }
.waypoint.done + .waypoint .line, .waypoint .line.done { background: var(--teal); }
.waypoint-label { font-family: var(--font-ui); font-size: 0.82rem; color: var(--text-soft); }

/* Breadcrumb */
.breadcrumb { font-family: var(--font-ui); font-size: 0.82rem; color: var(--text-soft); margin-bottom: 18px; }
.breadcrumb a { color: var(--text-soft); }
.breadcrumb .sep { margin: 0 6px; color: var(--text-faint); }

/* Page header band */
.page-hero {
  background: var(--ink); color: #fff; padding: 56px 0 44px;
  background-image: radial-gradient(circle at 85% -10%, rgba(226,150,58,0.18), transparent 55%);
}
.page-hero h1 { color: #fff; }
.page-hero .lede { color: #c3cbdc; }
.page-hero .breadcrumb, .page-hero .breadcrumb a { color: #9aa5bd; }

/* Grid helpers */
.grid { display: grid; gap: 22px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 900px) { .grid-3, .grid-4 { grid-template-columns: repeat(2,1fr); } }
@media (max-width: 620px) { .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; } }

/* Stats */
.stat { text-align: left; }
.stat .num { font-family: var(--font-display); font-size: 2.4rem; color: var(--ink); font-weight: 600; }
html.dark .stat .num { color: #fff; }
.stat .label { font-family: var(--font-ui); font-size: 0.82rem; color: var(--text-soft); text-transform: uppercase; letter-spacing: 0.05em; }

/* Tables */
table.data-table { width: 100%; border-collapse: collapse; font-family: var(--font-ui); font-size: 0.92rem; }
table.data-table th { text-align: left; font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.05em; color: var(--text-soft); border-bottom: 2px solid var(--border); padding: 10px 12px; }
table.data-table td { padding: 12px; border-bottom: 1px solid var(--border-soft); vertical-align: top; }
table.data-table tr:hover td { background: var(--border-soft); }

/* Forms */
.form-group { margin-bottom: 18px; }
label.form-label { display: block; font-family: var(--font-ui); font-size: 0.86rem; font-weight: 600; margin-bottom: 6px; color: var(--ink); }
html.dark label.form-label { color: var(--text); }
.form-control {
  width: 100%; padding: 11px 14px; border: 1px solid var(--border); border-radius: var(--radius-sm);
  font-family: var(--font-ui); font-size: 0.92rem; background: var(--surface); color: var(--text);
}
.form-control:focus { outline: 2px solid var(--teal); outline-offset: 1px; border-color: var(--teal); }
textarea.form-control { resize: vertical; min-height: 110px; }
.form-hint { font-size: 0.78rem; color: var(--text-faint); margin-top: 4px; }
.form-required { color: var(--red); }

.dropzone {
  border: 2px dashed var(--border); border-radius: var(--radius); padding: 36px 20px; text-align: center;
  background: var(--border-soft); cursor: pointer; transition: border-color .15s ease, background .15s ease;
}
.dropzone.dragover { border-color: var(--teal); background: rgba(30,114,104,0.06); }
.dropzone .dz-icon { font-size: 2rem; margin-bottom: 8px; }

.alert { padding: 14px 18px; border-radius: var(--radius-sm); font-size: 0.9rem; margin-bottom: 20px; }
.alert-success { background: rgba(30,114,104,0.1); color: var(--teal-dark); border: 1px solid rgba(30,114,104,0.25); }
.alert-error { background: rgba(185,74,61,0.08); color: var(--red); border: 1px solid rgba(185,74,61,0.25); }
.alert-info { background: rgba(226,150,58,0.1); color: var(--amber-dark); border: 1px solid rgba(226,150,58,0.25); }

/* Article page */
.article-meta-box {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px 24px; font-family: var(--font-ui); font-size: 0.85rem; color: var(--text-soft);
  display: flex; flex-wrap: wrap; gap: 8px 28px; margin-bottom: 28px;
}
.article-meta-box strong { color: var(--ink); }
html.dark .article-meta-box strong { color: var(--text); }
.article-body { font-family: var(--font-body); font-size: 1.06rem; }
.article-body h3 { margin-top: 1.6em; }
.abstract-box {
  background: var(--border-soft); border-left: 3px solid var(--teal); padding: 18px 22px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0; margin-bottom: 24px; font-family: var(--font-body);
}
.keyword-list span { display: inline-block; margin: 3px 6px 3px 0; }

/* Footer */
footer.site-footer { background: var(--ink); color: #b7c0d4; padding: 56px 0 0; font-family: var(--font-ui); font-size: 0.88rem; }
footer.site-footer h4 { color: #fff; font-family: var(--font-ui); font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.06em; margin-bottom: 16px; }
footer.site-footer a { color: #b7c0d4; }
footer.site-footer a:hover { color: #fff; }
footer.site-footer .footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 32px; padding-bottom: 40px; }
footer.site-footer .footer-grid p, footer.site-footer .footer-grid li { margin-bottom: 8px; }
footer.site-footer ul { list-style: none; padding: 0; margin: 0; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.1); padding: 18px 0; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; font-size: 0.8rem; color: #8792aa; }
.social-row { display: flex; gap: 10px; margin-top: 14px; }
.social-row a { width: 34px; height: 34px; border-radius: 50%; border: 1px solid rgba(255,255,255,0.2); display: flex; align-items: center; justify-content: center; }
.social-row a:hover { background: rgba(255,255,255,0.1); }
@media (max-width: 900px) { footer.site-footer .footer-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 560px) { footer.site-footer .footer-grid { grid-template-columns: 1fr; } }

/* Reveal on scroll */
.reveal { opacity: 0; transform: translateY(16px); transition: opacity .5s ease, transform .5s ease; }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) { .reveal { opacity: 1; transform: none; transition: none; } }

/* Utility */
.text-soft { color: var(--text-soft); }
.text-faint { color: var(--text-faint); }
.mt-0{margin-top:0} .mb-0{margin-bottom:0}
.flex { display: flex; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-8 { gap: 8px; } .gap-12 { gap: 12px; } .gap-16 { gap: 16px; }
.hidden { display: none !important; }

:focus-visible { outline: 2px solid var(--teal); outline-offset: 2px; }