/* Last modified: 2026-04-01--0200 */

/* ============================================
   GRAM RESEARCH — Global Styles
   ============================================ */

/* --- CSS Reset & Base --- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Libre Franklin', 'Helvetica Neue', Arial, sans-serif;
  font-weight: 400;
  line-height: 1.7;
  color: var(--white);
  background-color: var(--black);
}

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

a {
  color: var(--teal);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--teal-light);
}

ul, ol {
  list-style: none;
}

/* --- Brand Colors --- */
:root {
  /* Primary */
  --teal: #18AEB9;
  --teal-light: #3fd4df;
  --teal-dark: #0e8a93;
  --white: #FCFCFA;
  --white-70: rgba(252, 252, 250, 0.7);
  --white-50: rgba(252, 252, 250, 0.5);
  --white-20: rgba(252, 252, 250, 0.2);
  --white-10: rgba(252, 252, 250, 0.1);

  /* Secondary */
  --lavender: #7a7196;
  --salmon: #ffa399;
  --mint: #a8e5c4;

  /* Tertiary */
  --black: #302d2b;
  --black-deep: #1a1816;
  --grey: #a6a6a6;
  --grey-dark: #555;
  --navy: rgb(20, 23, 46);

  /* Layout */
  --max-width: 1200px;
  --max-width-narrow: 900px;
  --section-padding: 100px 0;
  --section-padding-sm: 60px 0;
  --container-padding: 0 24px;

  /* Typography scale */
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 2rem;
  --text-4xl: 2.75rem;
  --text-5xl: 3.5rem;
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
  font-family: 'Montserrat', 'Helvetica Neue', Arial, sans-serif;
  font-weight: 800;
  line-height: 1.2;
  color: var(--white);
}

h1 { font-size: var(--text-5xl); margin-bottom: 24px; }
h2 { font-size: var(--text-4xl); margin-bottom: 20px; }
h3 { font-size: var(--text-2xl); margin-bottom: 16px; }
h4 { font-size: var(--text-xl); margin-bottom: 12px; }

p {
  margin-bottom: 16px;
  color: var(--white-70);
}

.text-teal { color: var(--teal); }
.text-white { color: var(--white); }
.text-muted { color: var(--white-50); }

.lead {
  font-size: var(--text-xl);
  line-height: 1.6;
  color: var(--white-70);
}

/* --- Layout --- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--container-padding);
}

.container--narrow {
  max-width: var(--max-width-narrow);
}

.section {
  padding: var(--section-padding);
}

.section--dark {
  background-color: var(--black-deep);
}

.section--teal {
  background-color: var(--teal);
}

.section--teal h2,
.section--teal h3,
.section--teal p {
  color: var(--white);
}

.section--navy {
  background-color: var(--navy);
}

.section--navy h2,
.section--navy h3,
.section--navy p {
  color: var(--white);
}

.section--white {
  background-color: var(--white);
}

.section--white h2,
.section--white h3,
.section--white .section-title,
.section--white .section-label {
  color: var(--black);
}

.section--white p,
.section--white .section-subtitle,
.section--white .card__text {
  color: var(--grey-dark);
}

.section--white .card {
  background-color: rgba(48, 45, 43, 0.05);
  border-color: rgba(48, 45, 43, 0.1);
}

.section--white .card__title {
  color: var(--black);
}

.section--white .logo-bar img {
  filter: none;
}

/* --- Grid --- */
.grid {
  display: grid;
  gap: 32px;
}

.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }

.grid--2-1 { grid-template-columns: 2fr 1fr; }
.grid--1-2 { grid-template-columns: 1fr 2fr; }
.grid--1-1 { grid-template-columns: 1fr 1fr; }

/* --- Flexbox Utilities --- */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.flex-wrap { flex-wrap: wrap; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-16 { gap: 16px; }
.gap-24 { gap: 24px; }
.gap-32 { gap: 32px; }
.gap-48 { gap: 48px; }

/* --- Text Alignment --- */
.text-center { text-align: center; }
.text-left { text-align: left; }

/* --- Section Headers --- */
.section-label {
  font-family: 'Montserrat', sans-serif;
  font-size: var(--text-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 3px;
  color: var(--teal);
  margin-bottom: 16px;
}

.section-title {
  font-size: var(--text-4xl);
  margin-bottom: 20px;
}

.section-subtitle {
  font-size: var(--text-lg);
  color: var(--white-70);
  max-width: 640px;
}

.section-header {
  margin-bottom: 60px;
}

.section-header.text-center .section-subtitle {
  margin-left: auto;
  margin-right: auto;
}

/* --- Buttons --- */
.btn {
  display: inline-block;
  font-family: 'Montserrat', sans-serif;
  font-size: var(--text-sm);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  padding: 14px 32px;
  border-radius: 4px;
  border: 2px solid transparent;
  cursor: pointer;
  transition: all 0.25s ease;
}

.btn--primary {
  background-color: var(--teal);
  color: var(--white);
  border-color: var(--teal);
}

.btn--primary:hover {
  background-color: var(--teal-dark);
  border-color: var(--teal-dark);
  color: var(--white);
}

.btn--outline {
  background-color: transparent;
  color: var(--teal);
  border-color: var(--teal);
}

.btn--outline:hover {
  background-color: var(--teal);
  color: var(--white);
}

.btn--white {
  background-color: var(--white);
  color: var(--black);
  border-color: var(--white);
}

.btn--white:hover {
  background-color: transparent;
  color: var(--white);
}

.btn--outline-white {
  background-color: transparent;
  color: var(--white);
  border-color: var(--white);
}

.btn--outline-white:hover {
  background-color: var(--white);
  color: var(--navy);
}

.btn--sm {
  padding: 12px 24px;
  font-size: var(--text-xs);
  min-height: 44px;
}

/* --- Cards --- */
.card {
  background-color: var(--white-10);
  border: 1px solid var(--white-10);
  border-radius: 8px;
  padding: 32px;
  transition: border-color 0.25s ease, transform 0.25s ease;
}

.card:hover {
  border-color: var(--teal);
  transform: translateY(-2px);
}

.card--lg {
  padding: 40px;
}

.card__icon {
  width: 48px;
  height: 48px;
  margin-bottom: 20px;
  color: var(--teal);
}

.card__title {
  font-size: var(--text-lg);
  margin-bottom: 12px;
}

.card__text {
  font-size: var(--text-sm);
  color: var(--white-70);
  margin-bottom: 0;
}

/* --- Feature Row (alternating image + text) --- */
.feature-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
  padding: 60px 0;
}

.feature-row:nth-child(even) .feature-row__image {
  order: 2;
}

.feature-row__image {
  border-radius: 8px;
  overflow: hidden;
  background-color: var(--white-10);
  aspect-ratio: 4/3;
  display: flex;
  align-items: center;
  justify-content: center;
}

.feature-row__image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.feature-row__image--placeholder {
  border: 2px dashed var(--white-20);
  color: var(--white-50);
  font-size: var(--text-sm);
  font-family: 'Montserrat', sans-serif;
  text-align: center;
  padding: 24px;
}

.feature-row__content h3 {
  color: var(--white);
}

.feature-row__content p {
  color: var(--white-70);
}

.feature-row__content .section-label {
  color: var(--teal);
}

/* --- Comparison Table --- */
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--text-sm);
}

.comparison-table th,
.comparison-table td {
  padding: 16px 20px;
  text-align: left;
  border-bottom: 1px solid var(--white-10);
}

.comparison-table thead th {
  font-family: 'Montserrat', sans-serif;
  font-weight: 700;
  font-size: var(--text-base);
  color: var(--white);
  border-bottom: 2px solid var(--teal);
  padding-bottom: 12px;
}

.comparison-table tbody th {
  color: var(--white-70);
  font-weight: 400;
}

.comparison-table tbody td {
  color: var(--white);
}

.comparison-table .highlight-col {
  background-color: rgba(24, 174, 185, 0.08);
}

.comparison-table .check {
  color: var(--teal);
  font-weight: 700;
}

.comparison-table .dash {
  color: var(--white-50);
}

/* --- Logo Bar --- */
.logo-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 40px;
  padding: 20px 0;
}

.logo-bar img {
  width: auto;
  opacity: 1;
}

/* --- Broken Image Handling --- */
img {
  position: relative;
}

img::after {
  content: attr(alt);
  display: flex;
  align-items: center;
  justify-content: center;
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: var(--white-10);
  color: var(--white-50);
  font-size: var(--text-xs);
  font-family: 'Montserrat', sans-serif;
  text-align: center;
  padding: 8px;
  border-radius: 4px;
}

/* Logo placeholders */
.site-logo img,
.logo-bar img {
  min-height: 36px;
  min-width: 36px;
}

.logo-bar__item {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 40px;
  padding: 0 8px;
  color: var(--white-50);
  font-family: 'Montserrat', sans-serif;
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 1px;
  text-transform: uppercase;
  opacity: 0.6;
  transition: opacity 0.3s ease;
}

.logo-bar__item:hover {
  opacity: 1;
}

/* --- Publication Abstracts --- */
.pub-abstract {
  font-size: var(--text-sm);
  color: var(--white-50);
  line-height: 1.6;
  margin-top: 8px;
  margin-bottom: 8px;
}

.pub-doi {
  font-size: var(--text-xs);
  color: var(--white-50);
}

.pub-doi a {
  color: var(--teal);
}

.pub-toggle {
  background: none;
  border: none;
  color: var(--teal);
  font-family: 'Montserrat', sans-serif;
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 1px;
  text-transform: uppercase;
  cursor: pointer;
  padding: 4px 0;
  margin-top: 4px;
}

.pub-toggle:hover {
  color: var(--teal-light);
}

.pub-abstract--collapsed {
  display: none;
}

/* --- Publication List --- */
.pub-item {
  padding: 28px 0;
  border-bottom: 1px solid var(--white-10);
}

.pub-item:first-child {
  padding-top: 0;
}

.pub-year {
  font-family: 'Montserrat', sans-serif;
  font-size: var(--text-xs);
  font-weight: 700;
  color: var(--teal);
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: 8px;
}

.pub-title {
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--white);
  margin-bottom: 8px;
  line-height: 1.4;
}

.pub-title a {
  color: var(--white);
}

.pub-title a:hover {
  color: var(--teal);
}

.pub-authors {
  font-size: var(--text-sm);
  color: var(--white-50);
  margin-bottom: 4px;
}

.pub-journal {
  font-size: var(--text-sm);
  color: var(--white-50);
  font-style: italic;
}

/* --- Header / Navigation --- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background-color: var(--black-deep);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--white-10);
  transition: background-color 0.3s ease;
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 72px;
}

.site-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--white);
  font-family: 'Montserrat', sans-serif;
  font-weight: 700;
  font-size: var(--text-xl);
  letter-spacing: 1px;
}

.site-logo img {
  height: 36px;
  width: auto;
  object-fit: contain;
}

.site-logo:hover {
  color: var(--white);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.site-nav__link {
  font-family: 'Montserrat', sans-serif;
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--white-70);
  letter-spacing: 0.5px;
  padding: 8px 0;
  position: relative;
}

.site-nav__link:hover,
.site-nav__link--active {
  color: var(--white);
}

.site-nav__link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--teal);
  transition: width 0.25s ease;
}

.site-nav__link:hover::after,
.site-nav__link--active::after {
  width: 100%;
}

.nav-cta {
  margin-left: 8px;
}

/* Mobile menu toggle */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--white);
  font-size: 24px;
  cursor: pointer;
  padding: 8px;
}

/* --- Hero --- */
.hero {
  padding: 160px 0 100px;
  position: relative;
  overflow: hidden;
}

.hero--large {
  padding: 180px 0 120px;
  min-height: 80vh;
  display: flex;
  align-items: center;
}

.hero--white {
  background-color: var(--white);
}

.hero--white .hero__title {
  color: var(--black);
}

.hero--white .hero__subtitle {
  color: var(--grey-dark);
}

.hero__content {
  max-width: 700px;
  position: relative;
  z-index: 2;
}

.hero__title {
  font-size: var(--text-5xl);
  line-height: 1.1;
  margin-bottom: 24px;
}

.hero__subtitle {
  font-size: var(--text-xl);
  color: var(--white-70);
  margin-bottom: 36px;
  max-width: 560px;
}

.hero__cta {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

/* --- Page Hero (inner pages) --- */
.page-hero {
  padding: 140px 0 60px;
}

.page-hero__title {
  font-size: var(--text-4xl);
  margin-bottom: 16px;
}

.page-hero__subtitle {
  font-size: var(--text-lg);
  color: var(--white-70);
  max-width: 600px;
}

/* --- Footer --- */
.site-footer {
  background-color: var(--black-deep);
  border-top: 1px solid var(--white-10);
  padding: 60px 0 40px;
}

.footer__grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer__brand {
  max-width: 280px;
}

.footer__brand p {
  font-size: var(--text-sm);
  color: var(--white-50);
  margin-top: 16px;
}

.footer__heading {
  font-family: 'Montserrat', sans-serif;
  font-size: var(--text-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 2px;
  color: var(--white);
  margin-bottom: 20px;
}

.footer__links {
  display: flex;
  gap: 24px;
}

.footer__links a {
  display: block;
  font-size: var(--text-sm);
  color: var(--white-50);
  padding: 4px 0;
}

.footer__links a:hover {
  color: var(--teal);
}

.footer__bottom {
  border-top: 1px solid var(--white-10);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer__copyright {
  font-size: var(--text-xs);
  color: var(--white-50);
}

/* --- Contact Form --- */
.form-group {
  margin-bottom: 24px;
}

.form-label {
  display: block;
  font-family: 'Montserrat', sans-serif;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--white);
  margin-bottom: 8px;
}

.form-input,
.form-textarea {
  width: 100%;
  padding: 14px 16px;
  background-color: var(--white-10);
  border: 1px solid var(--white-20);
  border-radius: 4px;
  color: var(--white);
  font-family: 'Libre Franklin', sans-serif;
  font-size: var(--text-base);
  transition: border-color 0.25s ease;
}

.form-input:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--teal);
}

.form-textarea {
  min-height: 140px;
  resize: vertical;
}

.form-input::placeholder,
.form-textarea::placeholder {
  color: var(--white-50);
}

/* --- App Notes Card --- */
.note-card {
  display: block;
  background-color: var(--white-10);
  border: 1px solid var(--white-10);
  border-radius: 8px;
  padding: 32px;
  transition: border-color 0.25s ease, transform 0.25s ease;
  color: var(--white);
}

.note-card:hover {
  border-color: var(--teal);
  transform: translateY(-2px);
  color: var(--white);
}

.note-card__label {
  font-family: 'Montserrat', sans-serif;
  font-size: var(--text-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 2px;
  color: var(--teal);
  margin-bottom: 12px;
}

.note-card__title {
  font-size: var(--text-xl);
  font-weight: 700;
  margin-bottom: 12px;
}

.note-card__desc {
  font-size: var(--text-sm);
  color: var(--white-70);
  margin-bottom: 16px;
}

.note-card__link {
  font-family: 'Montserrat', sans-serif;
  font-size: var(--text-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--teal);
}

/* --- Breadcrumb --- */
.breadcrumb {
  font-size: var(--text-sm);
  color: var(--white-50);
  margin-bottom: 24px;
  padding-top: 96px;
}

.breadcrumb a {
  color: var(--white-50);
}

.breadcrumb a:hover {
  color: var(--teal);
}

.breadcrumb .sep {
  margin: 0 8px;
}

/* --- Article (for app notes) --- */
.article-content {
  max-width: var(--max-width-narrow);
  margin: 0 auto;
}

.article-content h2 {
  font-size: var(--text-3xl);
  margin-top: 48px;
  margin-bottom: 20px;
}

.article-content h3 {
  font-size: var(--text-xl);
  margin-top: 36px;
  margin-bottom: 16px;
}

.article-content p {
  font-size: var(--text-base);
  line-height: 1.8;
  margin-bottom: 20px;
}

.article-content ul,
.article-content ol {
  margin-bottom: 20px;
  padding-left: 24px;
}

.article-content li {
  color: var(--white-70);
  margin-bottom: 8px;
  line-height: 1.7;
  list-style: disc;
}

.article-content ol li {
  list-style: decimal;
}

/* --- Lightbox --- */
.lightbox-trigger {
  cursor: zoom-in;
}

.lightbox-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(0, 0, 0, 0.9);
  z-index: 2000;
  align-items: center;
  justify-content: center;
  cursor: zoom-out;
}

.lightbox-overlay img {
  max-width: 90vw;
  max-height: 90vh;
  object-fit: contain;
  border-radius: 0;
}

.lightbox-overlay.active {
  display: flex;
}

/* --- White article content (app note bodies) --- */
.section--white .article-content h2,
.section--white .article-content h3 {
  color: var(--black);
}

.section--white .article-content p,
.section--white .article-content li {
  color: var(--grey-dark);
}

.section--white .article-content a {
  color: var(--teal);
}

.section--white .article-content strong {
  color: var(--black);
}

/* --- Responsive --- */
@media (max-width: 1024px) {
  h1, .hero__title { font-size: var(--text-4xl); }
  h2, .section-title { font-size: var(--text-3xl); }

  .grid--3 { grid-template-columns: repeat(2, 1fr); }
  .grid--4 { grid-template-columns: repeat(2, 1fr); }
  .footer__grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
  :root {
    --section-padding: 60px 0;
  }

  h1, .hero__title { font-size: var(--text-3xl); }
  h2, .section-title { font-size: var(--text-2xl); }

  .hero { padding: 120px 0 60px; }
  .hero--large { min-height: auto; padding: 140px 0 80px; }
  .page-hero { padding: 110px 0 40px; }

  .grid--2, .grid--3, .grid--4,
  .grid--2-1, .grid--1-2, .grid--1-1 {
    grid-template-columns: 1fr;
  }

  .feature-row {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .feature-row:nth-child(even) .feature-row__image {
    order: 0;
  }

  .footer__grid { grid-template-columns: 1fr; gap: 32px; }

  /* Mobile nav */
  .site-nav {
    display: none;
    position: absolute;
    top: 72px;
    left: 0;
    right: 0;
    flex-direction: column;
    background-color: var(--black-deep);
    padding: 24px;
    gap: 16px;
    border-bottom: 1px solid var(--white-10);
  }

  .site-nav--open {
    display: flex;
  }

  .nav-toggle {
    display: block;
  }

  .nav-cta {
    margin-left: 0;
  }

  .logo-bar {
    gap: 24px;
  }

  .logo-bar img {
    height: 48px;
  }

  .footer__bottom {
    flex-direction: column;
    gap: 12px;
    text-align: center;
  }

  .footer__links {
    flex-wrap: wrap;
    justify-content: center;
  }

  .hero__cta { flex-direction: column; }
  .btn { width: 100%; text-align: center; }
}

@media (max-width: 480px) {
  :root {
    --section-padding: 40px 0;
  }

  h1, .hero__title { font-size: var(--text-2xl); }
  h2, .section-title { font-size: var(--text-xl); }

  .hero { padding: 100px 0 40px; }
  .hero--large { padding: 110px 0 60px; }
  .page-hero { padding: 96px 0 32px; }

  .card { padding: 20px; }
  .card--lg { padding: 24px; }
  .note-card { padding: 20px; }

  .section-header { margin-bottom: 36px; }

  .feature-row { padding: 32px 0; gap: 24px; }

  .logo-bar { gap: 16px; }
  .logo-bar img { height: 40px; }

  .page-hero__subtitle { font-size: var(--text-base); }
}