/* ==========================================================================
   NorthBridge Ventures — design system
   Pure monochrome, Scandinavian-minimal, Stripe-proportions, premium/institutional.
   Typography: Manrope (brand/display) + Inter (functional/body). See DESIGN.md.
   ========================================================================== */

:root {
  --color-bg: #ffffff;
  --color-bg-off: #fafafa;
  --color-text: #0a0a0a;
  --color-text-secondary: #5c5c5c;
  --color-text-tertiary: #8a8a8a;
  --color-border: #e4e4e4;

  --color-inverted-bg: #0a0a0a;
  --color-inverted-text: #ffffff;
  --color-inverted-text-secondary: #a3a3a3;
  --color-inverted-border: #2a2a2a;

  --font-display: 'Manrope', -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;

  --fs-hero: clamp(2.75rem, 6vw, 5.25rem);
  --fs-h2: clamp(2rem, 4vw, 3.25rem);
  --fs-h3: clamp(1.25rem, 2vw, 1.5rem);
  --fs-body-lg: clamp(1.125rem, 1.5vw, 1.375rem);
  --fs-body: 1.0625rem;
  --fs-small: 0.875rem;
  --fs-eyebrow: 0.8125rem;

  --container-width: 1240px;
  --gutter: clamp(1.5rem, 5vw, 4rem);
  --section-padding: clamp(4rem, 10vw, 8rem);
  --measure: 40rem; /* ~640px constrained paragraph width */

  --radius-pill: 999px;
  --transition: 200ms ease;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

section[id] {
  scroll-margin-top: 4.5rem;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: 1.55;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 500;
  letter-spacing: -0.03em;
  line-height: 1.05;
}

p {
  margin: 0;
}

a {
  color: inherit;
  text-decoration: none;
}

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

.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

.eyebrow {
  display: block;
  font-family: var(--font-sans);
  font-size: var(--fs-eyebrow);
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-text-tertiary);
  margin-bottom: 1rem;
}

.section-inverted .eyebrow {
  color: var(--color-inverted-text-secondary);
}

/* ---- Buttons ---- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.9rem 1.75rem;
  border-radius: var(--radius-pill);
  font-family: var(--font-sans);
  font-size: var(--fs-small);
  font-weight: 500;
  letter-spacing: 0;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background var(--transition), color var(--transition), border-color var(--transition);
  white-space: nowrap;
}

.btn-primary {
  background: var(--color-text);
  color: var(--color-bg);
}

.btn-primary:hover {
  background: #2a2a2a;
}

.btn-secondary {
  background: transparent;
  color: var(--color-text);
  border-color: var(--color-border);
}

.btn-secondary:hover {
  border-color: var(--color-text);
}

.section-inverted .btn-primary {
  background: var(--color-inverted-text);
  color: var(--color-inverted-bg);
}

.section-inverted .btn-primary:hover {
  background: #d9d9d9;
}

.section-inverted .btn-secondary {
  color: var(--color-inverted-text);
  border-color: var(--color-inverted-border);
}

.section-inverted .btn-secondary:hover {
  border-color: var(--color-inverted-text);
}

/* ---- Nav ---- */

.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4.5rem;
}

.nav-logo {
  font-family: var(--font-display);
  font-size: 1.0625rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.nav-links {
  display: none;
  align-items: center;
  gap: clamp(1.25rem, 3vw, 2.5rem);
  list-style: none;
  margin: 0;
  padding: 0;
  font-family: var(--font-sans);
  font-size: var(--fs-small);
  font-weight: 500;
}

@media (min-width: 720px) {
  .nav-links {
    display: flex;
  }
}

.nav-links a {
  color: var(--color-text-secondary);
  transition: color var(--transition);
}

.nav-links a:hover {
  color: var(--color-text);
}

.nav-cta {
  display: none;
}

@media (min-width: 640px) {
  .nav-cta {
    display: inline-flex;
  }
}

/* ---- Hero ---- */

.hero {
  padding-top: clamp(3rem, 8vw, 5rem);
  padding-bottom: 0;
  overflow: hidden;
}

.hero-copy {
  padding-bottom: 1.5rem;
  text-align: center;
}

.hero-copy h1 {
  font-size: var(--fs-hero);
  max-width: 26ch;
  margin-left: auto;
  margin-right: auto;
}

.hero-actions {
  margin-top: 2.25rem;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.75rem;
}

.hero-globe-frame {
  width: 70%;
  margin: 0 auto;
  aspect-ratio: 1344 / 540;
  overflow: hidden;
}

.hero-globe-frame img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 33%;
}

@media (max-width: 640px) {
  .hero-globe-frame {
    width: 100%;
  }
}

/* ---- Section rhythm ---- */

.section {
  padding-top: var(--section-padding);
  padding-bottom: var(--section-padding);
  border-top: 1px solid var(--color-border);
}

.section-inverted {
  background: var(--color-inverted-bg);
  color: var(--color-inverted-text);
  border-top: 1px solid var(--color-inverted-border);
}

.section-header {
  max-width: 44rem;
  margin-bottom: clamp(2.5rem, 5vw, 4rem);
}

.section-header h2 {
  font-size: var(--fs-h2);
}

.section-header p {
  margin-top: 1.25rem;
  font-size: var(--fs-body-lg);
  color: var(--color-text-secondary);
  max-width: var(--measure);
}

.section-inverted .section-header p {
  color: var(--color-inverted-text-secondary);
}

/* ---- Approach / philosophy ---- */

.approach-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
}

@media (min-width: 720px) {
  .approach-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.approach-item {
  border-top: 1px solid var(--color-border);
  padding-top: 1.5rem;
}

.approach-item h3 {
  font-size: var(--fs-h3);
  font-weight: 500;
  letter-spacing: -0.02em;
}

.approach-item p {
  margin-top: 0.75rem;
  color: var(--color-text-secondary);
}

.section-inverted .approach-item {
  border-top-color: var(--color-inverted-border);
}

.section-inverted .approach-item p {
  color: var(--color-inverted-text-secondary);
}

.invest-cta {
  margin-top: clamp(2.5rem, 5vw, 4rem);
  padding-top: 2rem;
  border-top: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

@media (min-width: 720px) {
  .invest-cta {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 2rem;
  }
}

.invest-cta p {
  color: var(--color-text-secondary);
  max-width: 40rem;
}

.section-inverted .invest-cta {
  border-top-color: var(--color-inverted-border);
}

.section-inverted .invest-cta p {
  color: var(--color-inverted-text-secondary);
}

/* ---- Cases stack ---- */
/* Each .case-card's photo comes from a data-image attribute, applied to
   .case-card-media as an inline style by js/case-modal.js (relative url()s
   set via a CSS custom property resolve against the stylesheet, not the
   HTML page, so the image is set directly on the element instead). Until
   an image is set, a light placeholder gradient fills the slot. A white
   fade sits over the photo, strongest on the left where the caption reads,
   fading out toward the right so the photo shows through. Recommended
   source: ~2000px wide, ~21:9. */

.cases-grid {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.case-card {
  display: block;
  position: relative;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: 1.25rem;
  aspect-ratio: 21 / 9;
  cursor: pointer;
  color: var(--color-text);
  transition: border-color var(--transition), transform var(--transition);
}

@media (max-width: 720px) {
  .case-card {
    aspect-ratio: 4 / 3;
  }
}

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

.case-card-media {
  position: absolute;
  inset: 0;
  background-color: var(--color-bg-off);
  background-image: linear-gradient(135deg, #f1f1f1, #e4e4e4);
  background-size: cover;
  background-position: center;
  transition: transform 400ms ease;
}

.case-card:hover .case-card-media {
  transform: scale(1.03);
}

.case-card-fade {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    90deg,
    rgba(255, 255, 255, 0.97) 0%,
    rgba(255, 255, 255, 0.88) 30%,
    rgba(255, 255, 255, 0.45) 58%,
    rgba(255, 255, 255, 0) 80%
  );
}

.case-card-expand {
  position: absolute;
  z-index: 2;
  top: 1.5rem;
  right: 1.5rem;
  width: 1.75rem;
  height: 1.75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--color-border);
  border-radius: 50%;
  color: var(--color-text-tertiary);
  background: rgba(255, 255, 255, 0.75);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  transition: border-color var(--transition), color var(--transition), background var(--transition);
}

.case-card-expand svg {
  width: 0.8rem;
  height: 0.8rem;
}

.case-card:hover .case-card-expand {
  border-color: var(--color-text);
  color: var(--color-text);
  background: #fff;
}

.case-card-caption {
  position: relative;
  z-index: 1;
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  gap: 0.6rem;
  max-width: 30rem;
  padding: clamp(1.5rem, 4vw, 2.75rem);
}

.case-card-eyebrow {
  font-family: var(--font-sans);
  font-size: var(--fs-eyebrow);
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-text-tertiary);
}

.case-card-caption h3 {
  font-size: clamp(1.5rem, 3vw, 2.125rem);
  font-weight: 500;
  letter-spacing: -0.02em;
  color: var(--color-text);
}

.case-card-caption p {
  color: var(--color-text-secondary);
  max-width: 34ch;
}

.case-card-link {
  margin-top: 0.4rem;
  display: inline-flex;
  align-self: flex-start;
  align-items: center;
  gap: 0.4rem;
  font-family: var(--font-sans);
  font-size: var(--fs-small);
  font-weight: 500;
  color: var(--color-text);
  transition: gap var(--transition);
}

.case-card:hover .case-card-link {
  gap: 0.65rem;
}

/* ---- Join CTA ---- */

.cta-section {
  text-align: center;
}

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

.cta-section .section-header p {
  margin-left: auto;
  margin-right: auto;
}

.cta-actions {
  display: flex;
  justify-content: center;
  gap: 0.75rem;
  flex-wrap: wrap;
}

/* ---- Footer / contact ---- */

.footer {
  border-top: 1px solid var(--color-border);
  padding-top: 3rem;
  padding-bottom: 3rem;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

@media (min-width: 720px) {
  .footer-inner {
    flex-direction: row;
    align-items: flex-end;
    justify-content: space-between;
  }
}

.footer-brand {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.0625rem;
  letter-spacing: -0.02em;
}

.footer-meta {
  margin-top: 0.5rem;
  color: var(--color-text-secondary);
  font-size: var(--fs-small);
  max-width: 32ch;
}

.footer-links {
  display: flex;
  gap: 1.5rem;
  list-style: none;
  margin: 0;
  padding: 0;
  font-family: var(--font-sans);
  font-size: var(--fs-small);
  font-weight: 500;
}

.footer-links a {
  color: var(--color-text-secondary);
  transition: color var(--transition);
}

.footer-links a:hover {
  color: var(--color-text);
}

.footer.section-inverted {
  border-top-color: var(--color-inverted-border);
}

.footer.section-inverted .footer-meta {
  color: var(--color-inverted-text-secondary);
}

.footer.section-inverted .footer-links a {
  color: var(--color-inverted-text-secondary);
}

.footer.section-inverted .footer-links a:hover {
  color: var(--color-inverted-text);
}

/* ---- Case detail pages ---- */

.case-hero {
  padding-top: clamp(3rem, 8vw, 5rem);
  padding-bottom: clamp(2rem, 6vw, 3rem);
}

.case-hero-back {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-family: var(--font-sans);
  font-size: var(--fs-small);
  font-weight: 500;
  color: var(--color-text-secondary);
  margin-bottom: 2rem;
}

.case-hero-back:hover {
  color: var(--color-text);
}

.case-hero h1 {
  font-size: clamp(2.25rem, 5vw, 3.75rem);
  max-width: 18ch;
}

.case-hero p {
  margin-top: 1.5rem;
  font-size: var(--fs-body-lg);
  color: var(--color-text-secondary);
  max-width: var(--measure);
}

.case-meta {
  margin-top: 2.5rem;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
  max-width: 32rem;
}

@media (min-width: 560px) {
  .case-meta {
    grid-template-columns: repeat(3, 1fr);
  }
}

.case-meta-label {
  font-family: var(--font-sans);
  font-size: var(--fs-small);
  font-weight: 500;
  color: var(--color-text-tertiary);
}

.case-meta-value {
  margin-top: 0.35rem;
  font-family: var(--font-sans);
  font-weight: 500;
}

.case-body {
  max-width: var(--measure);
}

.case-body p + p {
  margin-top: 1.25rem;
}

.case-body p {
  color: var(--color-text-secondary);
  font-size: var(--fs-body-lg);
}

/* ---- Case modal (portfolio pop-up) ---- */

body.modal-open {
  overflow: hidden;
}

.case-modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: clamp(1.5rem, 6vw, 5rem) var(--gutter);
  overflow-y: auto;
  background: rgba(10, 10, 10, 0.55);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity var(--transition);
}

.case-modal-overlay.is-open {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.case-modal {
  position: relative;
  width: 100%;
  max-width: 42rem;
  margin: auto;
  background: var(--color-bg);
  border-radius: 1.5rem;
  overflow: hidden;
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.2);
  transform: translateY(16px) scale(0.98);
  opacity: 0;
  transition: transform var(--transition), opacity var(--transition);
}

.case-modal-overlay.is-open .case-modal {
  transform: translateY(0) scale(1);
  opacity: 1;
}

/* Image banner: same photo + white left-fade treatment as the homepage
   cards. js/case-modal.js sets the background-image inline per case. */
.case-modal-banner {
  position: relative;
  aspect-ratio: 21 / 9;
  background-color: var(--color-bg-off);
  background-image: linear-gradient(135deg, #f1f1f1, #e4e4e4);
  background-size: cover;
  background-position: center;
}

@media (max-width: 560px) {
  .case-modal-banner {
    aspect-ratio: 4 / 3;
  }
}

.case-modal-banner-fade {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    90deg,
    rgba(255, 255, 255, 0.97) 0%,
    rgba(255, 255, 255, 0.88) 34%,
    rgba(255, 255, 255, 0.4) 62%,
    rgba(255, 255, 255, 0) 84%
  );
}

.case-modal-banner-caption {
  position: relative;
  z-index: 1;
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 0.5rem;
  max-width: 26rem;
  padding: clamp(1.5rem, 4vw, 2.5rem);
}

.case-modal-banner-caption h2 {
  font-size: clamp(1.5rem, 3.5vw, 2.25rem);
  max-width: 18ch;
}

.case-modal-inner {
  padding: clamp(1.5rem, 4vw, 2.5rem) clamp(2rem, 5vw, 3rem) clamp(2rem, 5vw, 3rem);
}

.case-modal-handle {
  display: none;
}

.case-modal-close {
  position: absolute;
  z-index: 2;
  top: 1.5rem;
  right: 1.5rem;
  width: 2.25rem;
  height: 2.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--color-border);
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.75);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  color: var(--color-text-secondary);
  font-family: var(--font-sans);
  font-size: 1.35rem;
  line-height: 1;
  cursor: pointer;
  transition: border-color var(--transition), color var(--transition);
}

.case-modal-close:hover {
  border-color: var(--color-text);
  color: var(--color-text);
  background: #fff;
}

.case-modal-intro {
  font-size: var(--fs-body-lg);
  color: var(--color-text-secondary);
  max-width: var(--measure);
}

.case-modal-meta {
  margin-top: 2rem;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
  max-width: 32rem;
}

.case-modal-body {
  margin-top: 2rem;
}

.case-modal-body p + p {
  margin-top: 1.1rem;
}

.case-modal-body p {
  color: var(--color-text-secondary);
}

.case-modal-more {
  margin-top: 2.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--color-border);
}

.case-modal-more-title {
  font-family: var(--font-sans);
  font-size: var(--fs-small);
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--color-text-tertiary);
}

.case-modal-more-grid {
  margin-top: 1rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.75rem;
}

@media (min-width: 480px) {
  .case-modal-more-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.case-modal-more-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  border: 1px solid var(--color-border);
  border-radius: 0.75rem;
  padding: 1rem 1.25rem;
  background: none;
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 500;
  letter-spacing: -0.01em;
  color: var(--color-text);
  cursor: pointer;
  transition: border-color var(--transition), transform var(--transition);
}

.case-modal-more-card:hover {
  border-color: var(--color-text);
  transform: translateY(-2px);
}

.case-modal-more-link {
  font-family: var(--font-sans);
  font-size: var(--fs-small);
  font-weight: 500;
  color: var(--color-text-tertiary);
}

/* ---- Case modal: mobile bottom sheet ----
   Below 640px the centered/inset dialog becomes a full-width sheet pinned to
   the bottom of the viewport (Stripe's mobile pattern) instead of a card
   floating with margins on every side. */
@media (max-width: 640px) {
  .case-modal-overlay {
    align-items: flex-end;
    padding: 0;
  }

  .case-modal {
    max-width: 100%;
    max-height: 92vh;
    margin: 0;
    border-radius: 1.25rem 1.25rem 0 0;
    display: flex;
    flex-direction: column;
    transform: translateY(100%);
  }

  .case-modal-overlay.is-open .case-modal {
    transform: translateY(0);
  }

  .case-modal-handle {
    display: block;
    position: absolute;
    z-index: 2;
    top: 0.75rem;
    left: 50%;
    transform: translateX(-50%);
    width: 2.5rem;
    height: 0.3125rem;
    border-radius: var(--radius-pill);
    background: rgba(255, 255, 255, 0.8);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.15);
  }

  .case-modal-close {
    top: 1rem;
    right: 1rem;
  }

  #case-modal-content {
    flex: 1 1 auto;
    overflow-y: auto;
    min-height: 0;
  }
}