/* ============================================================
   gSAM-Chem website — shared stylesheet
   Edit the :root variables to change the color scheme.
   ============================================================ */

:root {
  --primary:   #1B4F72;   /* deep atmospheric blue (navbar, headings) */
  --accent:    #1A8A6E;   /* tropical teal (links, borders, buttons)  */
  --orange:    #D35400;   /* convection / lightning orange             */
  --light-bg:  #F0F7F4;   /* mint-tinted card background               */
  --text:      #2C3E50;   /* main body text                            */
  --muted:     #636e72;   /* secondary / caption text                  */
  --border:    #dfe6e9;   /* table and section borders                 */
  --white:     #ffffff;

  --font: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  --mono: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
}

/* ---- RESET ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { }

body {
  font-family: var(--font);
  color: var(--text);
  line-height: 1.65;
  background: var(--white);
  font-size: 16px;
  overflow-x: hidden;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

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

.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ============================================================
   NAVBAR
   ============================================================ */
.navbar {
  background: var(--primary);
  position: sticky;
  top: 0;
  z-index: 200;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.25);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 58px;
}

.brand {
  color: #ffffff;
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  text-decoration: none;
  white-space: nowrap;
}
.brand:hover { text-decoration: none; opacity: 0.9; }

.nav-links {
  display: flex;
  list-style: none;
  align-items: center;
  gap: 0.15rem;
}
.nav-links a {
  color: rgba(255, 255, 255, 0.82);
  padding: 0.4rem 0.8rem;
  border-radius: 4px;
  font-size: 0.9rem;
  transition: background 0.15s, color 0.15s;
  text-decoration: none;
  white-space: nowrap;
}
.nav-links a:hover,
.nav-links a.active { background: rgba(255,255,255,0.15); color: #fff; }

.btn-github {
  background: var(--accent) !important;
  color: #fff !important;
  font-weight: 600;
  margin-left: 0.25rem;
}
.btn-github:hover { background: #148a60 !important; }

/* ============================================================
   HERO (index.html)
   ============================================================ */
.hero {
  background: linear-gradient(155deg, #0c3349 0%, var(--primary) 40%, #177a60 75%, #20a060 100%);
  color: #fff;
  padding: 5.5rem 0 5rem;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero-inner {
  display: flex;
  align-items: center;
  gap: 3rem;
  text-align: left;
}

.hero-logo {
  flex: 0 0 auto;
}

.hero-logo img {
  width: 320px;
  height: auto;
  filter: drop-shadow(0 4px 24px rgba(0,0,0,0.45));
}

.hero-text {
  flex: 1 1 auto;
}

@media (max-width: 760px) {
  .hero-inner {
    flex-direction: column;
    text-align: center;
  }
  .hero-logo img { width: 180px; }
  .hero-text { text-align: center; }
  .hero .tagline { margin: 0 auto 2.5rem; }
  .hero-btns { justify-content: center; }
}

/* white wave at the bottom */
.hero::after {
  content: '';
  position: absolute;
  bottom: -1px; left: 0; right: 0;
  height: 60px;
  background: var(--white);
  clip-path: ellipse(60% 100% at 50% 100%);
}

.hero h1 {
  font-size: 3.4rem;
  font-weight: 900;
  letter-spacing: -1.5px;
  margin-bottom: 0.5rem;
  line-height: 1.1;
}

.hero .subtitle {
  font-size: 1.2rem;
  font-style: italic;
  opacity: 0.88;
  margin-bottom: 1.25rem;
}

.hero .tagline {
  font-size: 1.05rem;
  max-width: 640px;
  margin: 0 0 2.5rem;
  opacity: 0.84;
  line-height: 1.75;
}

.hero-btns {
  display: flex;
  gap: 1rem;
  justify-content: flex-start;
  flex-wrap: wrap;
  position: relative;
  z-index: 1;
}

/* Generic button */
.btn {
  display: inline-block;
  padding: 0.65rem 1.6rem;
  border-radius: 5px;
  font-weight: 600;
  font-size: 0.95rem;
  transition: opacity 0.15s, transform 0.1s;
  text-decoration: none;
  cursor: pointer;
}
.btn:hover { text-decoration: none; opacity: 0.9; transform: translateY(-1px); }

.btn-primary-white {
  background: var(--white);
  color: var(--primary);
}
.btn-outline-white {
  border: 2px solid rgba(255, 255, 255, 0.65);
  color: var(--white);
}

/* ============================================================
   FEATURE CARDS
   ============================================================ */
.features {
  padding: 4.5rem 0 3.5rem;
}

.section-title {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--primary);
  text-align: center;
  margin-bottom: 0.4rem;
}
.section-sub {
  text-align: center;
  color: var(--muted);
  margin-bottom: 2.5rem;
  font-size: 0.98rem;
}

.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(285px, 1fr));
  gap: 1.5rem;
}

.card {
  background: var(--light-bg);
  border-radius: 8px;
  padding: 1.75rem 1.5rem;
  border-left: 4px solid var(--accent);
}
.card.card-orange { border-left-color: var(--orange); }
.card.card-blue   { border-left-color: var(--primary); }


.card h3 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 0.6rem;
}
.card p {
  font-size: 0.9rem;
  color: var(--muted);
  line-height: 1.6;
}

/* ============================================================
   SPECS BAR (quick stats)
   ============================================================ */
.specs-bar {
  background: var(--primary);
  padding: 2.5rem 0;
}

.specs-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
}

.spec-item {
  text-align: center;
  color: #fff;
}
.spec-item .num {
  font-size: 2.2rem;
  font-weight: 900;
  color: #7ed6b8;
  line-height: 1;
}
.spec-item .label {
  font-size: 0.82rem;
  opacity: 0.75;
  margin-top: 0.3rem;
}

/* ============================================================
   KEY FINDING / QUOTE
   ============================================================ */
.finding-section {
  padding: 4rem 0;
  background: var(--light-bg);
}

.finding-box {
  max-width: 800px;
  margin: 0 auto;
  background: var(--white);
  border-radius: 10px;
  padding: 2.25rem 2.5rem;
  box-shadow: 0 4px 24px rgba(27,79,114,0.10);
  border-top: 5px solid var(--accent);
  text-align: center;
}

.finding-box p {
  font-size: 1.05rem;
  line-height: 1.75;
  color: var(--text);
}
.finding-box cite {
  display: block;
  margin-top: 1rem;
  font-size: 0.85rem;
  color: var(--muted);
  font-style: normal;
}

/* ============================================================
   PAGE HEADER (non-home pages)
   ============================================================ */
.page-header {
  background: linear-gradient(135deg, var(--primary) 0%, #177a60 100%);
  color: #fff;
  padding: 3rem 0 2.75rem;
}
.page-header h1 {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 0.4rem;
  letter-spacing: -0.5px;
}
.page-header p {
  font-size: 0.98rem;
  opacity: 0.85;
  max-width: 650px;
}

/* ============================================================
   CONTENT LAYOUT (with sidebar)
   ============================================================ */
.content-body {
  padding: 3rem 0 4.5rem;
}

.content-layout {
  display: grid;
  grid-template-columns: 210px 1fr;
  gap: 3rem;
  align-items: start;
}

/* Left sidebar TOC */
.content-sidebar {
  position: sticky;
  top: 76px;
  background: var(--light-bg);
  border-radius: 8px;
  padding: 1.25rem 1.1rem;
}

.content-sidebar h4 {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 1.2px;
  color: var(--muted);
  margin-bottom: 0.75rem;
}

.content-sidebar ul { list-style: none; }
.content-sidebar li { margin-bottom: 0.2rem; }
.content-sidebar a {
  display: block;
  font-size: 0.87rem;
  color: var(--text);
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  transition: background 0.12s;
}
.content-sidebar a:hover {
  background: rgba(26,138,110,0.12);
  text-decoration: none;
  color: var(--accent);
}

/* Main content area */
.content-main h2 {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--primary);
  margin: 3rem 0 1rem;
  padding-top: 1rem;
  border-top: 2px solid var(--border);
  scroll-margin-top: 80px;
}
.content-main h2:first-child {
  margin-top: 0;
  border-top: none;
  padding-top: 0;
}
.content-main h3 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text);
  margin: 1.75rem 0 0.6rem;
  scroll-margin-top: 80px;
}
.content-main p  { margin-bottom: 1rem; font-size: 0.95rem; }
.content-main ul,
.content-main ol { margin: 0.5rem 0 1rem 1.5rem; font-size: 0.95rem; }
.content-main li { margin-bottom: 0.3rem; }

/* Tables */
.content-main table {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0 1.5rem;
  font-size: 0.875rem;
}
.content-main th {
  background: var(--primary);
  color: #fff;
  padding: 0.55rem 0.75rem;
  text-align: left;
  font-weight: 600;
}
.content-main td {
  padding: 0.45rem 0.75rem;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}
.content-main tr:nth-child(even) td { background: var(--light-bg); }

/* Inline code and code blocks */
.content-main code {
  background: #f1f3f5;
  padding: 0.15rem 0.4rem;
  border-radius: 3px;
  font-family: var(--mono);
  font-size: 0.85em;
  color: var(--primary);
}
.content-main pre {
  background: #1e2a36;
  color: #cdd6df;
  padding: 1.25rem 1.4rem;
  border-radius: 6px;
  overflow-x: auto;
  margin: 1rem 0 1.5rem;
  font-family: var(--mono);
  font-size: 0.85rem;
  line-height: 1.55;
}
.content-main pre code {
  background: none;
  color: inherit;
  padding: 0;
  font-size: inherit;
}

/* Note / warning boxes */
.note {
  padding: 0.85rem 1rem 0.85rem 1.1rem;
  border-left: 4px solid #3498db;
  background: #eaf6ff;
  border-radius: 0 5px 5px 0;
  margin: 1rem 0;
  font-size: 0.9rem;
  line-height: 1.55;
}
.note.warning {
  border-color: var(--orange);
  background: #fff5eb;
}
.note strong { color: var(--primary); }

/* ============================================================
   PUBLICATIONS PAGE
   ============================================================ */
.pub-list { list-style: none; }

.pub-item {
  padding: 1.25rem 1.35rem;
  background: var(--light-bg);
  border-radius: 8px;
  margin-bottom: 1rem;
  border-left: 4px solid var(--accent);
}
.pub-item.preprint { border-left-color: var(--orange); }

.pub-badge {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  padding: 0.15rem 0.5rem;
  border-radius: 3px;
  vertical-align: middle;
  margin-left: 0.4rem;
}
.badge-preprint { background: #fde8d0; color: var(--orange); }
.badge-related  { background: #d8f0e8; color: var(--accent); }

.pub-title {
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--primary);
  margin-bottom: 0.3rem;
}
.pub-title a {
  color: var(--primary);
}
.pub-title a:hover {
  color: var(--accent);
}
.pub-authors { font-size: 0.85rem; color: var(--muted); margin-bottom: 0.2rem; }
.pub-journal { font-size: 0.85rem; font-style: italic; color: var(--muted); }
.pub-links { margin-top: 0.5rem; font-size: 0.82rem; }
.pub-links a { margin-right: 0.75rem; }

/* ============================================================
   TEAM CARDS
   ============================================================ */
.team-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(170px, 1fr));
  gap: 1.25rem;
  margin-top: 1.5rem;
}

.team-card {
  display: block;
  text-align: center;
  padding: 1.5rem 1rem 1.25rem;
  background: var(--light-bg);
  border-radius: 8px;
  transition: box-shadow 0.15s;
  text-decoration: none;
  color: inherit;
}
.team-card:hover {
  box-shadow: 0 4px 16px rgba(27,79,114,0.12);
  text-decoration: none;
}

.team-avatar {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  background: var(--primary);
  margin: 0 auto 0.75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  font-weight: 800;
  color: #fff;
  letter-spacing: -1px;
}

.team-photo {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  object-fit: cover;
  object-position: top;
  margin: 0 auto 0.75rem;
  display: block;
  border: 3px solid var(--border);
}

.team-name {
  font-weight: 700;
  font-size: 0.88rem;
  color: var(--primary);
  margin-bottom: 0.2rem;
}
.team-role { font-size: 0.78rem; color: var(--muted); line-height: 1.4; }

/* ============================================================
   FOOTER
   ============================================================ */
footer {
  background: var(--primary);
  color: rgba(255, 255, 255, 0.65);
  padding: 1.75rem 0;
  text-align: center;
  font-size: 0.83rem;
}
footer a { color: rgba(255,255,255,0.85); }
footer a:hover { color: #fff; }

/* ============================================================
   HAMBURGER BUTTON (hidden on desktop)
   ============================================================ */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  cursor: pointer;
  padding: 6px;
  background: none;
  border: none;
  border-radius: 4px;
}
.hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: transform 0.2s ease, opacity 0.15s ease;
}
.hamburger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.open span:nth-child(2) { opacity: 0; }
.hamburger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 800px) {
  .content-layout { grid-template-columns: 1fr; }
  .content-sidebar { display: none; }
}

@media (max-width: 768px) {
  /* Show hamburger, collapse inline nav into a dropdown */
  .hamburger { display: flex; }

  .nav-links {
    display: none;
    position: absolute;
    top: 58px;
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--primary);
    padding: 0.4rem 0 0.75rem;
    box-shadow: 0 6px 16px rgba(0,0,0,0.3);
    z-index: 199;
    gap: 0;
  }
  .nav-links.open { display: flex; }

  .nav-links li { width: 100%; }

  /* Full-width links so the active/hover background covers the whole row */
  .nav-links a {
    display: block;
    width: 100%;
    box-sizing: border-box;
    padding: 0.75rem 1.5rem;
    border-radius: 0;
    font-size: 0.95rem;
    white-space: normal;
  }

  .btn-github {
    display: block;
    margin: 0.25rem 1rem 0 !important;
    border-radius: 5px !important;
    text-align: center;
    width: calc(100% - 2rem) !important;
    box-sizing: border-box;
  }

  /* Tighten page-header on mobile */
  .page-header { padding: 2rem 0 1.75rem; }
  .page-header h1 { font-size: 1.6rem; }
  .page-header p { font-size: 0.9rem; }
}

@media (max-width: 640px) {
  .hero { padding: 3.5rem 0 3rem; }
  .hero h1 { font-size: 2.3rem; }
  .specs-grid { grid-template-columns: repeat(2, 1fr); }
  .team-grid  { grid-template-columns: repeat(2, 1fr); }

  /* Scrollable tables on narrow screens */
  .content-main table {
    display: block;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }
  .content-main td,
  .content-main th {
    min-width: 100px;
  }

  /* Slightly smaller code blocks */
  .content-main pre {
    font-size: 0.78rem;
    padding: 1rem;
    max-width: 100%;
    overflow-x: auto;
  }

  /* Smaller font overall — keeps desktop size untouched */
  body { font-size: 14px; }

  /* Smaller h2 on mobile */
  .content-main h2 { font-size: 1.2rem; }
}