:root {
  color-scheme: light;
  --accent: #2563eb;
  --accent-strong: #1d4ed8;
  --accent-soft: #eff6ff;
  --border: #dbe3ef;
  --ink: #172033;
  --muted: #64748b;
  --paper: #fbfaf7;
  --panel: #fffdfa;
  --panel-blue: #eef4ff;
}

* {
  box-sizing: border-box;
}

html {
  overflow-x: hidden;
}

body {
  background:
    linear-gradient(rgba(37, 99, 235, 0.032) 1px, transparent 1px),
    linear-gradient(90deg, rgba(37, 99, 235, 0.026) 1px, transparent 1px),
    var(--paper);
  background-size: 84px 84px;
  color: var(--ink);
  display: flex;
  flex-direction: column;
  font-family:
    ui-sans-serif,
    system-ui,
    sans-serif,
    "Apple Color Emoji",
    "Segoe UI Emoji",
    "Segoe UI Symbol",
    "Noto Color Emoji";
  line-height: 1.5;
  margin: 0;
  min-height: 100dvh;
  overflow-x: hidden;
  position: relative;
}

.math-curve-background {
  height: 100dvh;
  inset: 0;
  pointer-events: none;
  position: fixed;
  width: 100vw;
  z-index: 0;
}

a {
  color: inherit;
}

.static-main,
.static-footer-inner {
  margin: 0 auto;
  max-width: 80rem;
  padding-left: 1rem;
  padding-right: 1rem;
}

.static-main,
.static-footer {
  position: relative;
  z-index: 1;
}

.app-header {
  background: rgba(255, 253, 250, 0.92);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 20;
}

.app-header-shell {
  align-items: center;
  display: flex;
  gap: 1.25rem;
  justify-content: space-between;
  margin: 0 auto;
  max-width: 80rem;
  min-height: 4.5rem;
  padding: 0.85rem 1rem;
}

.app-brand {
  min-width: 0;
}

.app-brand-link {
  color: var(--ink);
  display: inline-flex;
  font-size: 1.1rem;
  font-weight: 780;
  letter-spacing: 0;
  line-height: 1.1;
  text-decoration: none;
}

.app-brand-link:hover {
  color: var(--accent);
}

.app-brand p {
  color: var(--muted);
  font-size: 0.82rem;
  line-height: 1.35;
  margin: 0.2rem 0 0;
  max-width: 28rem;
}

.app-nav {
  align-items: center;
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  justify-content: flex-end;
}

.app-nav-button {
  align-items: center;
  appearance: none;
  background: transparent;
  border: 1px solid transparent;
  border-radius: 999px;
  color: #334155;
  cursor: pointer;
  display: inline-flex;
  font-family: inherit;
  font-size: 0.875rem;
  font-weight: 700;
  gap: 0.45rem;
  height: 2.25rem;
  line-height: 1;
  min-height: 2.25rem;
  padding: 0.45rem 0.85rem;
  text-decoration: none;
  transition:
    background-color 160ms ease,
    border-color 160ms ease,
    color 160ms ease,
    transform 160ms ease;
  white-space: nowrap;
}

.app-nav-button:hover {
  background: var(--accent-soft);
  border-color: #bfdbfe;
  color: var(--ink);
}

.app-nav-button:active,
.static-button:active,
.static-text-link:active {
  transform: translateY(1px);
}

.app-nav-button-active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fffdfa;
}

.app-nav-button-active:hover {
  background: var(--accent-strong);
  border-color: var(--accent-strong);
  color: #fffdfa;
}

.lock-icon {
  display: inline-block;
  flex: 0 0 auto;
  height: 0.9rem;
  position: relative;
  width: 0.74rem;
}

.lock-icon::before,
.lock-icon::after {
  content: "";
  position: absolute;
}

.lock-icon::before {
  border: 1.5px solid currentColor;
  border-bottom: 0;
  border-radius: 999px 999px 0 0;
  height: 0.42rem;
  left: 50%;
  top: 0;
  transform: translateX(-50%);
  width: 0.44rem;
}

.lock-icon::after {
  border: 1.5px solid currentColor;
  border-radius: 0.16rem;
  bottom: 0;
  display: inline-block;
  height: 0.52rem;
  left: 0;
  width: 100%;
}

.static-main {
  flex: 1 0 auto;
  padding-bottom: 2rem;
  padding-top: clamp(1.25rem, 3vw, 2.5rem);
}

.static-breadcrumbs {
  color: var(--muted);
  font-size: 0.86rem;
  margin-bottom: 1.2rem;
}

.static-breadcrumbs a {
  color: var(--accent-strong);
  font-weight: 700;
  text-decoration: none;
}

.static-breadcrumbs a:hover {
  text-decoration: underline;
  text-underline-offset: 0.18rem;
}

.static-hero {
  align-items: stretch;
  display: grid;
  gap: clamp(1.25rem, 4vw, 3rem);
  grid-template-columns: minmax(0, 1fr) minmax(18rem, 27rem);
  margin-bottom: clamp(1.25rem, 3vw, 2.25rem);
  padding: clamp(1.25rem, 3vw, 2.25rem) 0 0.75rem;
}

.static-hero h1 {
  color: var(--ink);
  font-size: clamp(2.6rem, 6vw, 5rem);
  font-weight: 780;
  letter-spacing: 0;
  line-height: 0.94;
  margin: 0;
  max-width: 14ch;
}

.static-lede {
  color: #475569;
  font-size: clamp(1rem, 1.5vw, 1.1rem);
  line-height: 1.65;
  margin: 1rem 0 0;
  max-width: 44rem;
}

.static-hero-panel {
  background:
    radial-gradient(circle at 20% 18%, rgba(37, 99, 235, 0.16), transparent 34%),
    linear-gradient(145deg, var(--panel-blue) 0%, var(--panel) 64%, #f8fafc 100%);
  border: 1px solid var(--border);
  border-radius: 1.25rem;
  box-shadow: 0 22px 58px rgba(23, 32, 51, 0.1);
  display: grid;
  align-content: start;
  gap: 0.9rem;
  padding: 1.1rem;
}

.static-hero-panel p {
  color: #475569;
  font-size: 0.94rem;
  line-height: 1.55;
  margin: 0;
}

.static-button,
.static-text-link {
  align-items: center;
  border-radius: 999px;
  display: inline-flex;
  font-size: 0.92rem;
  font-weight: 780;
  justify-content: center;
  min-height: 2.7rem;
  text-decoration: none;
  transition:
    background-color 160ms ease,
    border-color 160ms ease,
    color 160ms ease,
    transform 160ms ease;
  white-space: nowrap;
}

.static-button {
  background: var(--ink);
  border: 1px solid var(--ink);
  color: #fffdfa;
  padding: 0.72rem 1rem;
}

.static-button:hover {
  background: var(--accent);
  border-color: var(--accent);
}

.static-text-link {
  border: 1px solid transparent;
  color: #334155;
  padding: 0.45rem 0.75rem;
}

.static-text-link:hover {
  background: var(--accent-soft);
  border-color: #bfdbfe;
  color: var(--accent-strong);
}

.static-section {
  border-top: 1px solid var(--border);
  margin-top: clamp(1.35rem, 3.5vw, 2.75rem);
  padding-top: clamp(1rem, 2.6vw, 2rem);
}

.static-section h2 {
  color: var(--ink);
  font-size: clamp(1.65rem, 3vw, 2.65rem);
  font-weight: 780;
  line-height: 1.05;
  margin: 0;
  max-width: 34rem;
}

.static-section > p,
.static-card p,
.static-list dd,
.static-article p {
  color: var(--muted);
}

.static-section > p {
  font-size: 0.98rem;
  line-height: 1.7;
  max-width: 45rem;
}

.static-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin-top: 1rem;
}

.static-grid-2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.static-grid-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.static-card {
  background: rgba(255, 253, 250, 0.76);
  box-shadow: 0 0 0 1px var(--border);
  padding: 1.1rem;
}

.static-grid .static-card + .static-card {
  border-left: 0;
}

@media (min-width: 861px) {
  .static-grid-4.static-grid-fill::after {
    background: rgba(255, 253, 250, 0.76);
    box-shadow: 0 0 0 1px var(--border);
    content: "";
    min-height: 6.25rem;
  }
}

.static-card h3 {
  color: var(--ink);
  font-size: 1rem;
  font-weight: 780;
  line-height: 1.25;
  margin: 0;
}

.static-card p {
  font-size: 0.92rem;
  line-height: 1.6;
  margin: 0.45rem 0 0;
}

.static-card a {
  color: var(--ink);
  text-decoration: none;
}

.static-card a:hover {
  color: var(--accent-strong);
  text-decoration: underline;
  text-underline-offset: 0.18rem;
}

.static-tool-form {
  display: grid;
  gap: 0.75rem;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.static-tool-form label {
  color: #334155;
  display: grid;
  font-size: 0.82rem;
  font-weight: 780;
  gap: 0.35rem;
}

.static-tool-form select,
.static-tool-form input {
  background: var(--panel);
  border: 1px solid #cbd5e1;
  border-radius: 0.65rem;
  color: var(--ink);
  font: inherit;
  min-height: 2.45rem;
  padding: 0.55rem 0.65rem;
}

.static-tool-form select:focus,
.static-tool-form input:focus {
  border-color: var(--accent);
  outline: 2px solid rgba(37, 99, 235, 0.2);
  outline-offset: 1px;
}

.static-tool-form .static-form-full {
  grid-column: 1 / -1;
}

.static-sample-list,
.static-answer-list {
  border-bottom: 1px solid var(--border);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  list-style-position: inside;
  margin: 1rem 0 0;
  padding: 0;
}

.static-sample-list li,
.static-answer-list li {
  border-top: 1px solid var(--border);
  color: var(--ink);
  font-weight: 780;
  padding: 0.8rem 0.75rem;
}

.static-sample-list li:nth-child(even),
.static-answer-list li:nth-child(even) {
  border-left: 1px solid var(--border);
}

.static-answer-key {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 1rem;
  margin-top: 1rem;
  padding: 1rem;
}

.static-answer-key summary,
.static-faq summary {
  color: var(--ink);
  cursor: pointer;
  font-weight: 780;
}

.static-faq details {
  border-top: 1px solid var(--border);
  padding: 1rem 0;
}

.static-faq details:last-child {
  border-bottom: 1px solid var(--border);
}

.static-faq p {
  color: var(--muted);
  line-height: 1.6;
  margin: 0.55rem 0 0;
  max-width: 50rem;
}

.static-related-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  margin-top: 1rem;
}

.static-related-list a {
  background: var(--accent-soft);
  border: 1px solid #bfdbfe;
  border-radius: 999px;
  color: #1e3a8a;
  font-size: 0.88rem;
  font-weight: 780;
  padding: 0.5rem 0.8rem;
  text-decoration: none;
}

.static-related-list a:hover {
  background: var(--panel);
  color: var(--accent-strong);
}

.static-panel {
  background: var(--accent-soft);
  border: 1px solid #bfdbfe;
  border-radius: 1.25rem;
  margin-top: 1rem;
  padding: 1rem;
}

.static-panel p {
  color: var(--muted);
  line-height: 1.6;
  margin: 0;
  max-width: 44rem;
}

.static-panel .static-button {
  margin-top: 0.85rem;
}

.static-list {
  display: grid;
  gap: 0;
  margin: 0;
}

.static-list div {
  align-items: center;
  display: flex;
  gap: 0.8rem;
  justify-content: space-between;
  padding: 0.72rem 0;
}

.static-list div + div {
  border-top: 1px solid #dbeafe;
}

.static-list dt,
.static-list dd {
  margin: 0;
}

.static-list dt {
  color: #334155;
  font-weight: 780;
}

.static-list dd {
  color: var(--ink);
  font-weight: 700;
  text-align: right;
}

.pricing-main {
  padding-bottom: 1.25rem;
}

.pricing-main .static-hero {
  margin-bottom: 1rem;
  padding-top: clamp(1rem, 2vw, 1.6rem);
}

.pricing-main .static-section {
  margin-top: clamp(1rem, 2.4vw, 1.75rem);
  padding-top: clamp(0.85rem, 2vw, 1.35rem);
}

.pricing-main .static-card {
  padding: 0.85rem 1rem;
}

.pricing-main .static-panel {
  padding: 0.85rem 1rem;
}

.pricing-main .static-list {
  column-gap: 1.25rem;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.pricing-main .static-list div {
  border-top: 1px solid #dbeafe;
  padding: 0.55rem 0;
}

.pricing-main .static-list div:first-child,
.pricing-main .static-list div:nth-child(2) {
  border-top: 0;
}

.static-article {
  border-bottom: 1px solid var(--border);
  border-top: 1px solid var(--border);
  margin-top: 1.25rem;
  padding: 0.2rem 0 1rem;
}

.static-article h2 {
  color: var(--ink);
  font-size: 1.2rem;
  font-weight: 780;
  margin: 1.5rem 0 0;
}

.static-article h2:first-child {
  margin-top: 0.8rem;
}

.static-article p {
  line-height: 1.7;
  margin: 0.5rem 0 0;
  max-width: 58rem;
}

.static-footer {
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.9rem;
  margin-top: auto;
  width: 100%;
}

.static-footer-inner {
  align-items: start;
  display: grid;
  gap: clamp(1.5rem, 5vw, 5rem);
  grid-template-columns: minmax(16rem, 0.85fr) minmax(0, 1.15fr);
  padding-bottom: clamp(1.5rem, 3vw, 2rem);
  padding-top: clamp(1.75rem, 4vw, 2.75rem);
}

.static-footer-about {
  max-width: 24rem;
}

.static-footer-nav {
  display: grid;
  gap: 1.25rem;
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.static-footer-nav div {
  display: grid;
  gap: 0.45rem;
  justify-items: start;
}

.static-footer-nav h2 {
  color: var(--muted);
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  line-height: 1;
  margin: 0 0 0.35rem;
  text-transform: uppercase;
}

.static-footer a {
  align-items: center;
  border: 1px solid transparent;
  border-radius: 999px;
  color: #334155;
  display: inline-flex;
  font-size: 0.9rem;
  font-weight: 700;
  gap: 0.45rem;
  line-height: 1.2;
  min-height: 1.75rem;
  padding: 0.18rem 0;
  text-decoration: none;
}

.static-footer a:hover {
  color: var(--accent-strong);
}

.static-footer-brand {
  color: var(--ink);
  display: inline-flex;
  font-weight: 780;
  line-height: 1.1;
}

.static-footer p {
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.5;
  margin: 0.65rem 0 0;
  max-width: 23rem;
}

@media (max-width: 767px) {
  .app-header-shell {
    align-items: flex-start;
    flex-direction: column;
  }

  .app-nav {
    justify-content: flex-start;
    width: 100%;
  }

  .app-nav-button {
    flex: 1 1 auto;
    justify-content: center;
  }
}

@media (max-width: 860px) {
  .static-hero,
  .static-grid,
  .static-grid-2,
  .static-grid-4,
  .static-footer-inner,
  .static-footer-nav {
    grid-template-columns: 1fr;
  }

  .static-hero h1 {
    max-width: 16ch;
  }

  .static-grid .static-card + .static-card,
  .static-sample-list li:nth-child(even),
  .static-answer-list li:nth-child(even) {
    border-left: 0;
  }

  .static-sample-list,
  .static-answer-list,
  .pricing-main .static-list,
  .static-tool-form {
    grid-template-columns: 1fr;
  }

  .pricing-main .static-list div:nth-child(2) {
    border-top: 1px solid #dbeafe;
  }

  .static-list div {
    align-items: start;
    flex-direction: column;
    gap: 0.25rem;
  }

  .static-list dd {
    text-align: left;
  }

  .static-footer-inner {
    gap: 1.4rem;
  }
}

@media print {
  .math-curve-background {
    display: none !important;
  }
}