/* ===================================================================
   Nebula – Product Page Styles
   Premium design system · Sans-serif · Restrained palette
   =================================================================== */

/* ---------- Custom properties ---------- */
:root {
  /* Brand primary (indigo) */
  --nb-accent: #6366f1;
  --nb-accent-hover: #4f46e5;
  --nb-accent-subtle: rgba(99,102,241,.06);
  --nb-accent-border: rgba(99,102,241,.1);
  /* Interactive accent (blue) — matches frontend app */
  --nb-blue: #3b82f6;
  --nb-blue-hover: #2563eb;
  --nb-blue-light: #60a5fa;
  /* Neutrals (Tailwind Gray scale — matches frontend app) */
  --nb-dark: #111827;
  --nb-dark-mid: #1f2937;
  --nb-dark-card: #1f2937;
  --nb-text: #111827;
  --nb-text-secondary: #6b7280;
  --nb-text-tertiary: #9ca3af;
  --nb-bg: #f9fafb;
  --nb-bg-card: #ffffff;
  --nb-border: #e5e7eb;
  --nb-border-subtle: #f3f4f6;
  /* Layout */
  --nb-radius: .75rem;
  --nb-radius-lg: 1rem;
  --nb-shadow-sm: 0 1px 2px rgba(0,0,0,.04), 0 1px 4px rgba(0,0,0,.02);
  --nb-shadow: 0 1px 3px rgba(0,0,0,.04), 0 4px 16px rgba(0,0,0,.04);
  --nb-shadow-lg: 0 2px 4px rgba(0,0,0,.02), 0 8px 32px rgba(0,0,0,.06);
  /* Semantic colors — matches frontend app */
  --nb-success: #10b981;
  --nb-warning: #f59e0b;
  --nb-error: #ef4444;
  --nb-transition: .2s ease;
}

/* ---------- Base ---------- */
body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  color: var(--nb-text);
  background: var(--nb-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}
main { flex: 1; }

h1, h2, h3, h4, h5, h6 {
  font-family: 'Inter', system-ui, sans-serif;
  font-weight: 700;
  color: var(--nb-text);
  letter-spacing: -.02em;
}

/* ---------- Links ---------- */
a { color: var(--nb-accent); }
a:hover { color: var(--nb-accent-hover); }

/* ---------- Override Bootstrap primary ---------- */
.btn-primary {
  background: var(--nb-accent);
  border-color: var(--nb-accent);
}
.btn-primary:hover, .btn-primary:focus-visible {
  background: var(--nb-accent-hover);
  border-color: var(--nb-accent-hover);
}
.btn-outline-primary {
  color: var(--nb-accent);
  border-color: var(--nb-accent);
}
.btn-outline-primary:hover {
  background: var(--nb-accent);
  border-color: var(--nb-accent);
}
.text-primary { color: var(--nb-accent) !important; }

/* ---------- Buttons ---------- */
.btn {
  border-radius: .5rem;
  font-weight: 600;
  font-size: .9rem;
  letter-spacing: -.005em;
  transition: all var(--nb-transition);
}
.btn-lg {
  padding: .75rem 2rem;
  font-size: .95rem;
}

/* ---------- Navbar ---------- */
.nb-navbar {
  background: rgba(250,250,250,.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--nb-border);
  padding: .75rem 0;
  z-index: 1030;
}
.nb-navbar .navbar-brand {
  font-weight: 800;
  letter-spacing: -.025em;
  font-size: 1.2rem;
  color: var(--nb-text) !important;
}
.nb-navbar .navbar-brand i { color: var(--nb-accent); }
.nb-navbar .nav-link {
  font-weight: 500;
  font-size: .875rem;
  color: var(--nb-text-secondary) !important;
  padding: .45rem .85rem !important;
  border-radius: .5rem;
  transition: color .15s, background .15s;
}
.nb-navbar .nav-link:hover {
  color: var(--nb-text) !important;
  background: rgba(0,0,0,.05);
}
.nb-navbar .nav-link.active {
  color: var(--nb-text) !important;
  font-weight: 600;
  background: rgba(0,0,0,.04);
}
.btn-nav-cta {
  display: inline-flex;
  align-items: center;
  background: var(--nb-accent);
  color: #fff !important;
  padding: .5rem 1.15rem !important;
  font-weight: 600;
  font-size: .84rem;
  border-radius: .5rem;
  text-decoration: none;
  transition: all var(--nb-transition);
  box-shadow: 0 1px 4px rgba(99,102,241,.2);
}
.btn-nav-cta:hover {
  background: var(--nb-accent-hover);
  color: #fff !important;
  box-shadow: 0 2px 8px rgba(99,102,241,.3);
  transform: translateY(-1px);
}
.nb-navbar .navbar-toggler {
  border: 1px solid var(--nb-border);
  padding: .35rem .6rem;
  border-radius: .5rem;
}
.nb-navbar .navbar-toggler:focus {
  box-shadow: 0 0 0 2px rgba(99,102,241,.15);
}
.nb-navbar .navbar-toggler-icon {
  filter: none;
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='%236b7280' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e");
}
/* Navbar collapsed state (mobile) */
.nb-navbar .navbar-collapse {
  padding-top: .5rem;
}
@media (min-width: 992px) {
  .nb-navbar .navbar-collapse {
    padding-top: 0;
  }
}
@media (max-width: 991.98px) {
  .nb-navbar .navbar-nav {
    padding: .5rem 0;
    gap: .15rem !important;
  }
  .nb-navbar .nav-link {
    padding: .5rem .75rem !important;
  }
  .btn-nav-cta {
    align-self: flex-start;
    margin-bottom: .5rem;
  }
}

/* ---------- Hero ---------- */
.nb-hero {
  background: var(--nb-dark);
  position: relative;
  overflow: hidden;
  padding: 6rem 0 7rem;
}
.nb-hero::after {
  content: "";
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  height: 140px;
  background: linear-gradient(to bottom, transparent, var(--nb-bg));
  pointer-events: none;
}
@media (min-width: 992px) {
  .nb-hero { padding: 8rem 0 9rem; }
}

.hero-glow {
  position: absolute;
  top: -20%;
  left: 50%;
  transform: translateX(-50%);
  width: 1200px;
  height: 800px;
  background: radial-gradient(ellipse at center, rgba(99,102,241,.15) 0%, transparent 65%);
  pointer-events: none;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: .45rem;
  padding: .35rem 1rem;
  border-radius: 999px;
  font-size: .78rem;
  font-weight: 600;
  background: rgba(99,102,241,.1);
  color: rgba(165,163,255,.8);
  border: 1px solid rgba(99,102,241,.2);
  letter-spacing: .01em;
}

.hero-title {
  font-size: clamp(2.75rem, 5.5vw, 4rem);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -.035em;
  color: #fff;
}

.hero-subtitle {
  font-weight: 400;
  font-size: 1.1rem;
  line-height: 1.7;
  color: rgba(255,255,255,.65);
  max-width: 440px;
}

.hero-platforms {
  font-size: .8rem;
  color: rgba(255,255,255,.5);
  letter-spacing: .01em;
}
.hero-meta {
  font-size: .78rem;
  color: rgba(255,255,255,.5);
  letter-spacing: .01em;
}
.hero-divider {
  width: 1px;
  height: 14px;
  background: rgba(255,255,255,.2);
}

.btn-hero-primary {
  background: var(--nb-accent);
  border: none;
  color: #fff;
  padding: .85rem 2rem;
  font-size: .95rem;
  border-radius: .625rem;
  font-weight: 600;
  box-shadow: 0 2px 16px rgba(99,102,241,.3);
  transition: all var(--nb-transition);
  text-decoration: none;
}
.btn-hero-primary:hover {
  background: var(--nb-accent-hover);
  color: #fff;
  box-shadow: 0 4px 24px rgba(99,102,241,.4);
  transform: translateY(-2px);
}
.btn-hero-secondary {
  border: 1px solid rgba(255,255,255,.15);
  color: rgba(255,255,255,.6);
  padding: .85rem 2rem;
  font-size: .95rem;
  border-radius: .625rem;
  font-weight: 500;
  background: rgba(255,255,255,.03);
  transition: all var(--nb-transition);
  text-decoration: none;
}
.btn-hero-secondary:hover {
  border-color: rgba(255,255,255,.3);
  color: rgba(255,255,255,.9);
  background: rgba(255,255,255,.06);
}

/* App window mockup – dark */
.app-window {
  background: var(--nb-dark-mid);
  border: 1px solid rgba(255,255,255,.1);
  border-radius: .875rem;
  overflow: hidden;
  box-shadow: 0 24px 64px rgba(0,0,0,.5), 0 0 0 1px rgba(255,255,255,.06), 0 0 120px rgba(99,102,241,.12);
}
.app-window-bar {
  display: flex;
  align-items: center;
  gap: .4rem;
  padding: .6rem .9rem;
  background: rgba(0,0,0,.3);
  border-bottom: 1px solid rgba(255,255,255,.04);
}
.app-window-dot {
  width: 8px; height: 8px;
  border-radius: 50%;
}
.app-window-dot--red    { background: #f87171; }
.app-window-dot--yellow { background: #fbbf24; }
.app-window-dot--green  { background: var(--nb-success); }
.app-window-body {
  padding: 1.5rem 2rem;
  min-height: 180px;
  font-family: 'Playfair Display', Georgia, serif;
  color: rgba(255,255,255,.45);
  font-size: .9rem;
  line-height: 1.9;
}
.app-window-body .cursor {
  display: inline-block;
  width: 2px;
  height: 1em;
  background: var(--nb-accent);
  margin-left: 2px;
  vertical-align: text-bottom;
  animation: blink 1s step-end infinite;
}
@keyframes blink { 50% { opacity: 0; } }
.app-window-sidebar {
  width: 160px;
  min-height: 180px;
  border-right: 1px solid rgba(255,255,255,.04);
  padding: .85rem .6rem;
  background: rgba(0,0,0,.15);
  flex-shrink: 0;
}
.sidebar-item {
  display: flex;
  align-items: center;
  gap: .35rem;
  padding: .35rem .55rem;
  border-radius: .3rem;
  font-size: .72rem;
  color: rgba(255,255,255,.3);
  margin-bottom: .15rem;
}
.sidebar-item.active {
  background: rgba(99,102,241,.15);
  color: rgba(255,255,255,.6);
}
@media (max-width: 767.98px) {
  .app-window-sidebar { display: none; }
  .app-window-body { padding: 1.25rem; font-size: .85rem; }
}

/* App window – light variant (cloud section) */
.app-window-light {
  background: var(--nb-bg-card);
  border: 1px solid var(--nb-border);
  box-shadow: var(--nb-shadow-lg);
}
.app-window-light .app-window-bar {
  background: var(--nb-bg);
  border-color: var(--nb-border);
}
.app-window-light .app-window-dot { background: #d1d5db; }

/* ---------- Sections ---------- */
.nb-section {
  padding: 5.5rem 0;
}
@media (min-width: 992px) {
  .nb-section { padding: 7rem 0; }
}

.nb-section-bordered {
  border-top: 1px solid var(--nb-border);
}

.section-label {
  font-size: .7rem;
  font-weight: 600;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--nb-text-tertiary);
  margin-bottom: .75rem;
}

.section-title {
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  font-weight: 800;
  letter-spacing: -.025em;
  line-height: 1.15;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--nb-text-secondary);
  max-width: 480px;
  line-height: 1.7;
}

/* ---------- Feature cards ---------- */
.feature-icon {
  width: 2.5rem;
  height: 2.5rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: .625rem;
  font-size: 1.05rem;
  flex-shrink: 0;
  background: var(--nb-accent-subtle);
  color: var(--nb-accent);
}
.feature-card {
  background: var(--nb-bg-card);
  border: 1px solid var(--nb-border);
  border-radius: var(--nb-radius);
  padding: 1.75rem;
  height: 100%;
  box-shadow: var(--nb-shadow-sm);
  transition: all var(--nb-transition);
}
.feature-card:hover {
  border-color: rgba(99,102,241,.15);
  box-shadow: var(--nb-shadow);
  transform: translateY(-2px);
}
.feature-card h3 {
  font-weight: 700;
  font-size: .95rem;
  letter-spacing: -.01em;
}

/* ---------- Cloud section ---------- */
.cloud-feature-row {
  display: flex;
  align-items: flex-start;
  gap: .875rem;
}
.cloud-feature-row strong {
  font-size: .9rem;
  letter-spacing: -.01em;
}
.cloud-feature-row .small {
  font-size: .82rem;
}
.cloud-feature-row .feature-icon {
  border-radius: 50%;
}

/* ---------- Preview cards ---------- */
.preview-card {
  background: var(--nb-bg-card);
  border: 1px solid var(--nb-border);
  border-radius: var(--nb-radius);
  overflow: hidden;
  box-shadow: var(--nb-shadow-sm);
  transition: all var(--nb-transition);
}
.preview-card:hover {
  box-shadow: var(--nb-shadow);
  transform: translateY(-2px);
}
.preview-mock {
  aspect-ratio: 16 / 10;
  display: flex;
  flex-direction: column;
  background: var(--nb-dark-mid);
  position: relative;
  overflow: hidden;
}
.preview-mock-bar {
  display: flex;
  align-items: center;
  gap: .3rem;
  padding: .35rem .6rem;
  background: rgba(0,0,0,.25);
}
.preview-mock-dot {
  width: 5px; height: 5px;
  border-radius: 50%;
  opacity: .6;
}
.preview-mock-body {
  flex: 1;
  padding: .75rem 1rem;
}
.preview-mock-line {
  height: 3px;
  border-radius: 2px;
  background: rgba(255,255,255,.06);
  margin-bottom: .4rem;
}
.preview-mock-line:nth-child(2) { width: 85%; }
.preview-mock-line:nth-child(3) { width: 70%; }
.preview-mock-line:nth-child(4) { width: 90%; }
.preview-mock-line:nth-child(5) { width: 60%; }
.preview-mock-line:nth-child(6) { width: 75%; }
.preview-mock-line:nth-child(7) { width: 45%; margin-bottom: .65rem; }
.preview-mock-line:nth-child(8) { width: 80%; }
.preview-mock-line:nth-child(9) { width: 65%; }

/* Preview – sidebar variant */
.preview-mock-sidebar {
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  width: 28%;
  background: rgba(0,0,0,.2);
  border-right: 1px solid rgba(255,255,255,.04);
  padding: 1.75rem .5rem .5rem;
}
.preview-mock-sidebar .preview-mock-line {
  background: rgba(255,255,255,.04);
  height: 2.5px;
  margin-bottom: .5rem;
}
.preview-mock-sidebar ~ .preview-mock-body {
  margin-left: 28%;
}

/* Preview – dark mode variant */
.preview-mock-dark {
  background: #111827;
}
.preview-mock-dark .preview-mock-bar {
  background: rgba(255,255,255,.02);
}
.preview-mock-dark .preview-mock-line {
  background: rgba(255,255,255,.04);
}

/* ---------- Open-source pillars ---------- */
.oss-pillar {
  text-align: center;
  padding: 0 .5rem;
}
.oss-pillar .feature-icon {
  margin: 0 auto .75rem;
}

/* ---------- FAQ ---------- */
.nb-accordion .accordion-item {
  border: 1px solid var(--nb-border);
  border-radius: var(--nb-radius) !important;
  margin-bottom: .65rem;
  overflow: hidden;
  background: var(--nb-bg-card);
}
.nb-accordion .accordion-button {
  font-weight: 600;
  font-size: .9rem;
  padding: 1rem 1.15rem;
  border-radius: var(--nb-radius) !important;
  color: var(--nb-text);
  background: var(--nb-bg-card);
}
.nb-accordion .accordion-button:not(.collapsed) {
  background: var(--nb-bg);
  color: var(--nb-text);
  box-shadow: none;
}
.nb-accordion .accordion-button:focus {
  box-shadow: 0 0 0 2px rgba(99,102,241,.12);
}
.nb-accordion .accordion-button::after {
  width: .9rem;
  height: .9rem;
  background-size: .9rem;
}
.nb-accordion .accordion-body {
  font-size: .88rem;
  color: var(--nb-text-secondary);
  line-height: 1.7;
  padding: 0 1.15rem 1rem;
}

/* ---------- CTA ---------- */
.nb-cta {
  background: var(--nb-bg-card);
  border-top: 1px solid var(--nb-border);
}

/* ---------- Donate cards ---------- */
.donate-card {
  background: var(--nb-bg-card);
  border: 1px solid var(--nb-border);
  border-radius: var(--nb-radius);
  padding: 2rem 1.5rem;
  text-align: center;
  transition: all var(--nb-transition);
  text-decoration: none;
  display: flex;
  flex-direction: column;
  align-items: center;
  height: 100%;
  box-shadow: var(--nb-shadow-sm);
}
.donate-card:hover {
  border-color: rgba(99,102,241,.15);
  box-shadow: var(--nb-shadow);
  transform: translateY(-2px);
}
.donate-icon {
  width: 3.25rem;
  height: 3.25rem;
  border-radius: .75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.35rem;
  margin-bottom: 1rem;
}

/* ---------- Signup card ---------- */
.signup-card {
  background: var(--nb-bg-card);
  border: 1px solid var(--nb-border);
  border-radius: var(--nb-radius-lg);
  box-shadow: var(--nb-shadow-lg);
}

/* ---------- Info card (donate page) ---------- */
.info-card {
  background: var(--nb-bg-card);
  border: 1px solid var(--nb-border);
  border-radius: var(--nb-radius);
  box-shadow: var(--nb-shadow-sm);
}

/* ---------- Table ---------- */
.nb-table thead th {
  font-size: .7rem;
  text-transform: uppercase;
  letter-spacing: .06em;
  color: var(--nb-text-tertiary);
  border-bottom: 1px solid var(--nb-border);
}
.nb-table td {
  font-size: .875rem;
  vertical-align: middle;
}
.badge-license {
  font-weight: 600;
  font-size: .65rem;
  letter-spacing: .03em;
  padding: .3em .6em;
}

/* ---------- Footer ---------- */
.nb-footer {
  background: var(--nb-dark);
  color: rgba(255,255,255,.4);
}
.nb-footer a {
  color: rgba(255,255,255,.4);
  text-decoration: none;
  transition: color .15s;
}
.nb-footer a:hover { color: rgba(255,255,255,.8); }
.nb-footer-brand {
  font-weight: 800;
  font-size: 1.1rem;
  color: #f9fafb;
  letter-spacing: -.02em;
}
.footer-heading {
  font-size: .65rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: rgba(255,255,255,.2);
  margin-bottom: .6rem;
}
.footer-link {
  display: block;
  font-size: .82rem;
  padding: .15rem 0;
}
.footer-icon-svg {
  width: 1em;
  height: 1em;
  vertical-align: -.125em;
  fill: currentColor;
}
.footer-divider {
  border-top: 1px solid rgba(255,255,255,.06);
}

/* ---------- Scroll-reveal ---------- */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity .5s ease, transform .5s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}
.reveal-stagger > .reveal:nth-child(2) { transition-delay: .06s; }
.reveal-stagger > .reveal:nth-child(3) { transition-delay: .12s; }
.reveal-stagger > .reveal:nth-child(4) { transition-delay: .18s; }
.reveal-stagger > .reveal:nth-child(5) { transition-delay: .24s; }
.reveal-stagger > .reveal:nth-child(6) { transition-delay: .30s; }

/* ---------- Skip link ---------- */
.skip-link {
  position: fixed;
  top: .5rem;
  left: 50%;
  transform: translateX(-50%) translateY(-120%);
  z-index: 9999;
  background: var(--nb-accent);
  color: #fff !important;
  padding: .5rem 1.25rem;
  border-radius: .5rem;
  font-weight: 600;
  font-size: .85rem;
  text-decoration: none;
  box-shadow: var(--nb-shadow-lg);
  transition: transform .15s ease;
}
.skip-link:focus {
  transform: translateX(-50%) translateY(0);
}

/* ---------- Pricing badge ---------- */
.pricing-badge {
  display: inline-block;
  background: var(--nb-accent);
  color: #fff;
  font-size: .65rem;
  font-weight: 700;
  letter-spacing: .04em;
  text-transform: uppercase;
  padding: .2rem .65rem;
  border-radius: 999px;
  margin-bottom: .5rem;
}

/* ---------- Focus styles ---------- */
.btn:focus-visible,
a:focus-visible {
  outline: 2px solid var(--nb-accent);
  outline-offset: 2px;
}

/* ---------- Scroll-reveal stagger (extended) ---------- */
.reveal-stagger > .reveal:nth-child(7) { transition-delay: .36s; }
.reveal-stagger > .reveal:nth-child(8) { transition-delay: .42s; }
.reveal-stagger > .reveal:nth-child(9) { transition-delay: .48s; }

/* ---------- Spinner (signup button) ---------- */
.spin {
  display: inline-block;
  animation: spin .8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ---------- Typography scale ---------- */
:root {
  --nb-fs-xs: .7rem;
  --nb-fs-sm: .8rem;
  --nb-fs-base: .875rem;
  --nb-fs-md: .9rem;
  --nb-fs-lg: .95rem;
  --nb-fs-xl: 1.05rem;
}

/* ---------- Container width utilities ---------- */
.container-narrow    { max-width: 520px; margin-left: auto; margin-right: auto; }
.container-sm        { max-width: 640px; }
.container-md        { max-width: 780px; }
.container-lg        { max-width: 860px; }
.container-xl        { max-width: 960px; }

/* ---------- Text color utilities ---------- */
.nb-text-secondary   { color: var(--nb-text-secondary) !important; }
.nb-text-tertiary    { color: var(--nb-text-tertiary) !important; }

/* ---------- Preview card content ---------- */
.preview-card-title  { font-size: var(--nb-fs-base); }
.preview-card-desc   { color: var(--nb-text-tertiary); font-size: var(--nb-fs-sm); }

/* ---------- Utility ---------- */
.font-sans { font-family: 'Inter', system-ui, sans-serif !important; }