/* Industrial Spine Research — shared stylesheet */
/* Pattern: matches the cfius-proximity / CFIUScheck.com visual language */

:root {
  --blue-deep: #1F4E79;
  --blue-med:  #2E75B6;
  --blue-lite: #D5E8F0;
  --gray-1: #1a1a1a;
  --gray-2: #595959;
  --gray-3: #8a8a8a;
  --gray-4: #d0d0d0;
  --gray-5: #f5f5f5;
  --gold: #BF8F00;
  --red:  #C00000;
  --white: #ffffff;
  --shadow-1: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-2: 0 4px 12px rgba(0,0,0,0.12);
  --radius:    8px;
  --maxw:      1100px;
  --font: "Inter", "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0; padding: 0;
  font-family: var(--font);
  color: var(--gray-1);
  background: var(--white);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

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

h1, h2, h3 { color: var(--blue-deep); font-weight: 700; line-height: 1.25; margin: 0 0 0.5em; }
h1 { font-size: 2.4rem; }
h2 { font-size: 1.7rem; }
h3 { font-size: 1.2rem; }
p { margin: 0 0 1em; }

/* Header */
.isr-header {
  display: flex; justify-content: space-between; align-items: center;
  padding: 1rem 2rem; border-bottom: 1px solid var(--gray-4); background: var(--white);
  position: sticky; top: 0; z-index: 50;
}
.isr-logo { display: flex; align-items: center; gap: 0.6rem; color: var(--blue-deep); font-weight: 700; }
.isr-logo:hover { text-decoration: none; }
.isr-logo-mark {
  width: 28px; height: 28px; background: var(--blue-deep); border-radius: 4px;
  display: inline-block;
  background: linear-gradient(135deg, var(--blue-deep) 0%, var(--blue-med) 100%);
}
.isr-logo-text { font-size: 1.05rem; }
.isr-nav { display: flex; gap: 1.4rem; align-items: center; }
.isr-nav a { color: var(--gray-1); font-size: 0.95rem; font-weight: 500; }
.isr-nav a:hover { color: var(--blue-med); text-decoration: none; }
.isr-nav-cta {
  padding: 0.45rem 1rem; border: 1px solid var(--blue-deep); border-radius: 6px;
  color: var(--blue-deep) !important;
}
.isr-nav-cta:hover { background: var(--blue-deep); color: var(--white) !important; }

/* Hero */
.isr-hero {
  padding: 4rem 2rem 3rem;
  background: linear-gradient(180deg, var(--gray-5) 0%, var(--white) 100%);
  border-bottom: 1px solid var(--gray-4);
}
.isr-hero-inner { max-width: var(--maxw); margin: 0 auto; }
.isr-eyebrow {
  text-transform: uppercase; letter-spacing: 0.08em; font-size: 0.85rem;
  color: var(--blue-med); font-weight: 600; margin-bottom: 0.5rem;
}
.isr-hero h1 { font-size: 2.8rem; margin-bottom: 1rem; max-width: 800px; }
.isr-lede { font-size: 1.15rem; color: var(--gray-2); max-width: 760px; }
.isr-hero-ctas { display: flex; gap: 0.8rem; margin-top: 1.6rem; flex-wrap: wrap; }

/* Buttons */
.isr-btn {
  display: inline-block; padding: 0.7rem 1.4rem; border-radius: 6px;
  font-weight: 600; font-size: 0.95rem; text-decoration: none; cursor: pointer;
  border: 1px solid transparent; transition: all 0.15s ease;
}
.isr-btn-primary { background: var(--blue-deep); color: var(--white); }
.isr-btn-primary:hover { background: var(--blue-med); text-decoration: none; }
.isr-btn-ghost { color: var(--blue-deep); border-color: var(--blue-deep); background: transparent; }
.isr-btn-ghost:hover { background: var(--blue-deep); color: var(--white); text-decoration: none; }

/* Sections */
.isr-section { padding: 4rem 2rem; }
.isr-section-alt { background: var(--gray-5); }
.isr-section-inner { max-width: var(--maxw); margin: 0 auto; }
.isr-section h2 { margin-bottom: 0.5rem; }
.isr-section-lede { color: var(--gray-2); font-size: 1.05rem; max-width: 760px; margin-bottom: 2rem; }

/* Grids */
.isr-grid-2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 1.5rem; }
.isr-grid-3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 1.5rem; }

/* Feature blocks */
.isr-feature {
  padding: 1.6rem; background: var(--white); border-radius: var(--radius);
  border: 1px solid var(--gray-4);
}
.isr-feature h3 { font-size: 1.1rem; }
.isr-feature p { color: var(--gray-2); font-size: 0.95rem; margin: 0; }

/* Cards (research items) */
.isr-card {
  padding: 2rem; background: var(--white); border-radius: var(--radius);
  border: 1px solid var(--gray-4); box-shadow: var(--shadow-1);
}
.isr-card-meta { display: flex; gap: 0.6rem; flex-wrap: wrap; margin-bottom: 1rem; }
.isr-card-tag {
  font-size: 0.78rem; padding: 0.25rem 0.7rem; border-radius: 4px;
  background: var(--blue-lite); color: var(--blue-deep); font-weight: 600;
  letter-spacing: 0.03em;
}
.isr-card-tag-pillar { background: var(--gray-5); color: var(--gray-1); }
.isr-card-tag-status { background: #d4edda; color: #155724; }
.isr-card h3 { font-size: 1.35rem; margin-bottom: 1rem; }
.isr-card p { color: var(--gray-2); }
.isr-card-footer {
  display: flex; justify-content: space-between; align-items: center;
  margin-top: 1.5rem; padding-top: 1.5rem; border-top: 1px solid var(--gray-4);
}
.isr-card-score { display: flex; flex-direction: column; gap: 0.1rem; }
.isr-score-label {
  font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--gray-3);
}
.isr-score-value { font-size: 1.5rem; font-weight: 700; color: var(--blue-deep); }

/* Tier pricing */
.isr-tier {
  padding: 2rem 1.6rem; background: var(--white); border-radius: var(--radius);
  border: 1px solid var(--gray-4); display: flex; flex-direction: column;
}
.isr-tier-featured { border: 2px solid var(--blue-deep); box-shadow: var(--shadow-2); }
.isr-tier h3 { font-size: 1.2rem; margin-bottom: 0.4rem; }
.isr-tier-price { font-size: 1.8rem; font-weight: 700; color: var(--blue-deep); margin: 0.3rem 0; }
.isr-tier-detail { font-size: 0.88rem; color: var(--gray-3); margin: 0 0 0.8rem; }
.isr-tier-savings {
  font-size: 0.85rem; color: var(--gold); font-weight: 600;
  background: #fef9e7; padding: 0.3rem 0.7rem; border-radius: 4px; display: inline-block;
  margin-bottom: 0.8rem; width: max-content;
}
.isr-tier ul { padding-left: 1.2rem; margin: 1rem 0 1.5rem; color: var(--gray-2); }
.isr-tier li { margin-bottom: 0.4rem; font-size: 0.93rem; }
.isr-tier .isr-btn { margin-top: auto; text-align: center; }

/* Status badges (inventory state) */
.isr-status-badge {
  display: inline-block; padding: 0.3rem 0.7rem; border-radius: 4px;
  font-size: 0.78rem; font-weight: 600; letter-spacing: 0.03em;
}
.isr-status-available { background: #d4edda; color: #155724; }
.isr-status-reserved { background: #fff3cd; color: #856404; }
.isr-status-sold { background: #f5f5f5; color: var(--gray-3); }
.isr-status-firstlook { background: var(--blue-lite); color: var(--blue-deep); }
.isr-card-availability { display: flex; flex-direction: column; align-items: flex-start; gap: 0.4rem; }
.isr-price { font-size: 1.5rem; font-weight: 700; color: var(--blue-deep); }
.isr-price-sold { color: var(--gray-3); text-decoration: line-through; }

/* Paper links */
.isr-paper {
  display: block; padding: 1.4rem; background: var(--white); border-radius: var(--radius);
  border: 1px solid var(--gray-4); transition: all 0.15s ease;
}
.isr-paper:hover { border-color: var(--blue-deep); box-shadow: var(--shadow-1); text-decoration: none; }
.isr-paper-tag {
  display: inline-block; font-size: 0.75rem; padding: 0.2rem 0.6rem;
  background: var(--blue-lite); color: var(--blue-deep); border-radius: 4px;
  font-weight: 600; margin-bottom: 0.6rem;
}
.isr-paper-title { display: block; font-weight: 600; color: var(--gray-1); margin-bottom: 0.3rem; }
.isr-paper-meta { display: block; font-size: 0.85rem; color: var(--gray-3); }

/* Footer */
.isr-footer { background: var(--gray-1); color: var(--gray-4); padding: 3rem 2rem; }
.isr-footer-inner { max-width: var(--maxw); margin: 0 auto; }
.isr-footer-firm { display: block; color: var(--white); font-weight: 700; font-size: 1.1rem; margin-bottom: 0.3rem; }
.isr-footer-tagline { display: block; color: var(--gray-3); font-size: 0.95rem; margin-bottom: 1.5rem; }
.isr-footer-nav { display: flex; gap: 1.4rem; flex-wrap: wrap; margin-bottom: 1.5rem; }
.isr-footer-nav a { color: var(--gray-4); font-size: 0.9rem; }
.isr-footer-nav a:hover { color: var(--white); text-decoration: none; }
.isr-footer-fineprint { color: var(--gray-3); font-size: 0.82rem; max-width: 700px; }

/* Forms */
.isr-form { display: flex; flex-direction: column; gap: 0.8rem; max-width: 480px; }
.isr-form label { font-size: 0.9rem; font-weight: 500; color: var(--gray-1); }
.isr-form input, .isr-form select, .isr-form textarea {
  padding: 0.65rem 0.8rem; border: 1px solid var(--gray-4); border-radius: 5px;
  font-family: inherit; font-size: 0.95rem;
}
.isr-form input:focus, .isr-form textarea:focus, .isr-form select:focus {
  border-color: var(--blue-med); outline: 2px solid var(--blue-lite);
}

/* Tables */
.isr-table { width: 100%; border-collapse: collapse; margin: 1rem 0; }
.isr-table th, .isr-table td {
  padding: 0.7rem 0.9rem; border-bottom: 1px solid var(--gray-4); text-align: left; font-size: 0.95rem;
}
.isr-table th { background: var(--blue-lite); color: var(--blue-deep); font-weight: 600; }
.isr-table tr:hover { background: var(--gray-5); }

/* Responsive */
@media (max-width: 720px) {
  .isr-header { padding: 0.8rem 1rem; flex-direction: column; gap: 0.8rem; }
  .isr-nav { flex-wrap: wrap; gap: 1rem; justify-content: center; }
  .isr-hero { padding: 2.5rem 1.2rem; }
  .isr-hero h1 { font-size: 2rem; }
  .isr-section { padding: 2.5rem 1.2rem; }
  h1 { font-size: 1.8rem; }
  h2 { font-size: 1.4rem; }
}