:root {
  --sp-ink: #171717;
  --sp-muted: #66645f;
  --sp-bg: #f5f5f1;
  --sp-surface: #ffffff;
  --sp-border: #deded7;
  --sp-accent: #5b59d6;
  --sp-accent-dark: #4341b8;
  --sp-accent-soft: #eeedff;
  --sp-success: #087a55;
  --sp-success-soft: #e7f6ef;
  --sp-warning: #a84d19;
  --sp-warning-soft: #fff1e8;
  --sp-radius: 18px;
  --sp-shadow: 0 18px 50px rgba(23, 23, 23, 0.08);
  --sp-container: 1120px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--sp-ink);
  background: var(--sp-bg);
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 17px;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
}
img { display: block; max-width: 100%; height: auto; }
a { color: var(--sp-accent-dark); text-underline-offset: 3px; }
a:hover { color: var(--sp-accent); }
button, input, select, textarea { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
:focus-visible { outline: 3px solid rgba(91, 89, 214, .35); outline-offset: 3px; }

.sp-container { width: min(calc(100% - 40px), var(--sp-container)); margin-inline: auto; }
.sp-narrow { width: min(calc(100% - 40px), 760px); margin-inline: auto; }
.sp-skip-link { position: fixed; top: 8px; left: 8px; z-index: 999; transform: translateY(-160%); padding: 10px 14px; color: #fff; background: var(--sp-ink); border-radius: 8px; }
.sp-skip-link:focus { transform: translateY(0); }

.sp-site-header { position: relative; z-index: 20; border-bottom: 1px solid var(--sp-border); background: rgba(245,245,241,.94); backdrop-filter: blur(12px); }
.sp-header-inner { min-height: 72px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.sp-brand { display: inline-flex; align-items: center; gap: 10px; color: var(--sp-ink); font-size: 16px; font-weight: 750; text-decoration: none; letter-spacing: -.02em; }
.sp-brand:hover { color: var(--sp-ink); }
.sp-brand-mark { display: grid; place-items: center; width: 34px; height: 34px; border-radius: 10px; color: #fff; background: var(--sp-ink); font-size: 11px; font-weight: 850; letter-spacing: -.04em; }
.sp-primary-nav ul { display: flex; align-items: center; gap: 26px; margin: 0; padding: 0; list-style: none; }
.sp-primary-nav a { color: #3d3c38; font-size: 14px; font-weight: 650; text-decoration: none; }
.sp-primary-nav a:hover { color: var(--sp-accent); }
.sp-nav-toggle { display: none; min-width: 44px; min-height: 44px; border: 1px solid var(--sp-border); border-radius: 11px; background: var(--sp-surface); color: var(--sp-ink); }

.sp-hero { padding: 76px 0 34px; text-align: center; }
.sp-eyebrow { margin: 0 0 14px; color: var(--sp-accent-dark); font-size: 13px; font-weight: 800; letter-spacing: .1em; text-transform: uppercase; }
.sp-hero h1, .sp-page-hero h1 { max-width: 900px; margin: 0 auto; font-size: clamp(2.55rem, 6vw, 5.2rem); line-height: 1.02; letter-spacing: -.065em; }
.sp-hero-lede { max-width: 720px; margin: 24px auto 0; color: var(--sp-muted); font-size: clamp(1.05rem, 2vw, 1.25rem); }
.sp-proof-row { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px 22px; margin: 26px 0 0; padding: 0; list-style: none; color: #45443f; font-size: 14px; font-weight: 600; }
.sp-proof-row li::before { content: "✓"; margin-right: 7px; color: var(--sp-success); font-weight: 900; }

.sp-calculator-shell { padding: 20px 0 76px; }
.sp-section { padding: 82px 0; }
.sp-section--surface { background: var(--sp-surface); border-block: 1px solid var(--sp-border); }
.sp-section--dark { color: #fff; background: var(--sp-ink); }
.sp-section-heading { max-width: 720px; margin-bottom: 34px; }
.sp-section-heading--center { margin-inline: auto; text-align: center; }
.sp-section-heading h2, .sp-content h2 { margin: 0 0 14px; font-size: clamp(2rem, 4vw, 3.25rem); line-height: 1.08; letter-spacing: -.045em; }
.sp-section-heading p { margin: 0; color: var(--sp-muted); }
.sp-section--dark .sp-section-heading p { color: #bcbcb6; }

.sp-case-grid { display: grid; grid-template-columns: .9fr 1.1fr; gap: 56px; align-items: start; }
.sp-case-copy h2 { margin: 0 0 16px; font-size: clamp(2rem, 4vw, 3.4rem); line-height: 1.08; letter-spacing: -.05em; }
.sp-case-copy > p { color: var(--sp-muted); }
.sp-case-table { overflow: hidden; border: 1px solid var(--sp-border); border-radius: var(--sp-radius); background: var(--sp-surface); box-shadow: var(--sp-shadow); }
.sp-case-row { display: flex; justify-content: space-between; gap: 24px; padding: 15px 20px; border-bottom: 1px solid var(--sp-border); }
.sp-case-row:last-child { border-bottom: 0; }
.sp-case-row span { color: var(--sp-muted); }
.sp-case-row strong { text-align: right; }
.sp-case-row--total { color: #fff; background: var(--sp-ink); }
.sp-case-row--total span { color: #d7d7d1; }
.sp-case-note { margin: 16px 0 0; color: var(--sp-muted); font-size: 13px; }

.sp-card-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.sp-card { display: flex; flex-direction: column; min-height: 270px; padding: 28px; color: var(--sp-ink); background: var(--sp-surface); border: 1px solid var(--sp-border); border-radius: var(--sp-radius); text-decoration: none; transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease; }
.sp-card:hover { color: var(--sp-ink); border-color: #b8b6df; box-shadow: var(--sp-shadow); transform: translateY(-3px); }
.sp-card-kicker { color: var(--sp-accent-dark); font-size: 12px; font-weight: 800; letter-spacing: .08em; text-transform: uppercase; }
.sp-card h3 { margin: 26px 0 10px; font-size: 1.45rem; line-height: 1.15; letter-spacing: -.03em; }
.sp-card p { margin: 0; color: var(--sp-muted); font-size: 15px; }
.sp-card-link { margin-top: auto; padding-top: 22px; font-weight: 750; }

.sp-formula-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.sp-formula { padding: 26px; color: var(--sp-ink); background: #fff; border-radius: var(--sp-radius); }
.sp-formula h3 { margin: 0 0 8px; font-size: 1.15rem; }
.sp-formula code { display: block; overflow-x: auto; margin-top: 16px; padding: 14px 16px; color: #242332; background: var(--sp-accent-soft); border-radius: 10px; font-size: 14px; }
.sp-section--dark .sp-formula { background: #282826; color: #fff; }
.sp-section--dark .sp-formula p { color: #c6c6bf; }
.sp-section--dark .sp-formula code { color: #fff; background: #37364c; }

.sp-steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; margin: 0; padding: 0; list-style: none; counter-reset: steps; }
.sp-steps li { counter-increment: steps; }
.sp-steps li::before { content: "0" counter(steps); display: block; margin-bottom: 20px; color: var(--sp-accent); font-size: 14px; font-weight: 850; }
.sp-steps h3 { margin: 0 0 8px; }
.sp-steps p { margin: 0; color: var(--sp-muted); }

.sp-button { display: inline-flex; min-height: 46px; align-items: center; justify-content: center; padding: 10px 17px; border: 1px solid transparent; border-radius: 11px; font-weight: 750; text-decoration: none; cursor: pointer; }
.sp-button--primary { color: #fff; background: var(--sp-accent); }
.sp-button--primary:hover { color: #fff; background: var(--sp-accent-dark); }
.sp-button--quiet { color: var(--sp-ink); background: #fff; border-color: var(--sp-border); }
.sp-button-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }

.sp-page-hero { padding: 70px 0 44px; }
.sp-page-hero h1 { margin: 0; font-size: clamp(2.4rem, 5vw, 4.7rem); }
.sp-page-hero p { max-width: 760px; margin: 22px 0 0; color: var(--sp-muted); font-size: 1.16rem; }
.sp-page-hero-meta { display: flex; flex-wrap: wrap; gap: 10px 20px; margin-top: 22px; color: var(--sp-muted); font-size: 14px; }

.sp-content-wrap { padding: 10px 0 90px; }
.sp-content { color: #292925; }
.sp-content > * { max-width: 760px; margin-inline: auto; }
.sp-content > .alignwide, .sp-content > table, .sp-content > .sp-wide { max-width: 980px; }
.sp-content h2 { margin-top: 64px; font-size: clamp(1.75rem, 3vw, 2.55rem); }
.sp-content h3 { margin-top: 38px; margin-bottom: 10px; font-size: 1.35rem; line-height: 1.25; }
.sp-content p { margin-top: 0; margin-bottom: 22px; }
.sp-content ul, .sp-content ol { margin-top: 0; margin-bottom: 26px; padding-left: 24px; }
.sp-content li { margin-bottom: 8px; }
.sp-content table { width: 100%; margin-top: 30px; margin-bottom: 36px; border-collapse: collapse; background: var(--sp-surface); border: 1px solid var(--sp-border); }
.sp-content th, .sp-content td { padding: 13px 15px; border-bottom: 1px solid var(--sp-border); text-align: left; vertical-align: top; }
.sp-content th { background: #ecece7; font-size: 14px; }
.sp-content blockquote, .sp-callout { max-width: 820px; margin-top: 34px; margin-bottom: 34px; padding: 22px 24px; background: var(--sp-accent-soft); border-left: 4px solid var(--sp-accent); border-radius: 0 12px 12px 0; }
.sp-content blockquote p:last-child, .sp-callout p:last-child { margin-bottom: 0; }
.sp-tool-embed { max-width: 1120px !important; margin-top: 34px; margin-bottom: 46px; }
.sp-source-list { font-size: 14px; word-break: break-word; }
.sp-updated { margin-top: 54px !important; padding-top: 20px; border-top: 1px solid var(--sp-border); color: var(--sp-muted); font-size: 14px; }

.sp-guides-index { padding-bottom: 90px; }
.sp-post-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.sp-post-card { padding: 26px; background: #fff; border: 1px solid var(--sp-border); border-radius: var(--sp-radius); }
.sp-post-card h2 { margin: 12px 0 10px; font-size: 1.35rem; line-height: 1.2; }
.sp-post-card h2 a { color: var(--sp-ink); text-decoration: none; }
.sp-post-card p { color: var(--sp-muted); font-size: 15px; }
.sp-post-meta { color: var(--sp-accent-dark); font-size: 12px; font-weight: 800; letter-spacing: .06em; text-transform: uppercase; }
.sp-pagination { margin-top: 32px; }
.sp-pagination .nav-links { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.sp-pagination .page-numbers { display: inline-flex; min-width: 44px; min-height: 44px; align-items: center; justify-content: center; padding: 8px 12px; border: 1px solid var(--sp-border); border-radius: 10px; color: var(--sp-ink); background: #fff; text-decoration: none; }
.sp-pagination .page-numbers.current { color: #fff; background: var(--sp-accent-dark); border-color: var(--sp-accent-dark); }
.sp-pagination a:hover, .sp-pagination a:focus-visible { border-color: var(--sp-accent); }

.sp-contact-form { display: grid; gap: 18px; max-width: 680px; }
.sp-contact-form label { display: grid; gap: 7px; font-weight: 700; }
.sp-contact-form input, .sp-contact-form textarea { width: 100%; padding: 12px 14px; color: var(--sp-ink); background: #fff; border: 1px solid #c9c9c2; border-radius: 10px; }
.sp-contact-form textarea { resize: vertical; }
.sp-form-note { color: var(--sp-muted); font-size: 13px; }
.sp-honeypot { position: absolute; left: -10000px; width: 1px; height: 1px; overflow: hidden; }
.sp-notice { max-width: 680px; margin-bottom: 22px; padding: 14px 16px; border-radius: 10px; }
.sp-notice--success { color: #07583f; background: var(--sp-success-soft); }
.sp-notice--error { color: #8e350b; background: var(--sp-warning-soft); }

.sp-site-footer { padding: 66px 0 28px; color: #d3d3cd; background: var(--sp-ink); }
.sp-footer-grid { display: grid; grid-template-columns: 1.7fr 1fr 1fr; gap: 56px; }
.sp-brand--footer { color: #fff; }
.sp-brand--footer:hover { color: #fff; }
.sp-brand--footer .sp-brand-mark { color: var(--sp-ink); background: #fff; }
.sp-footer-grid p { max-width: 420px; color: #aaa9a3; font-size: 14px; }
.sp-footer-grid h2 { margin: 0 0 14px; color: #fff; font-size: 13px; text-transform: uppercase; letter-spacing: .08em; }
.sp-footer-grid ul { margin: 0; padding: 0; list-style: none; }
.sp-footer-grid li { margin-bottom: 8px; }
.sp-footer-grid a:not(.sp-brand) { color: #d3d3cd; font-size: 14px; text-decoration: none; }
.sp-footer-grid a:hover { color: #fff; }
.sp-footer-bottom { display: flex; justify-content: space-between; gap: 20px; margin-top: 48px; padding-top: 20px; border-top: 1px solid #353533; color: #8e8d88; font-size: 12px; }
.sp-footer-bottom p { margin: 0; }

.sp-consent { position: fixed; right: 20px; bottom: 20px; z-index: 100; display: flex; max-width: 640px; align-items: center; gap: 22px; padding: 18px; background: #fff; border: 1px solid var(--sp-border); border-radius: 16px; box-shadow: var(--sp-shadow); }
.sp-consent[hidden] { display: none; }
.sp-consent strong { display: block; }
.sp-consent p { margin: 3px 0 0; color: var(--sp-muted); font-size: 13px; }
.sp-consent-actions { display: flex; flex-shrink: 0; gap: 8px; }

.sp-404 { padding: 110px 0; text-align: center; }
.sp-404 h1 { margin: 0 0 16px; font-size: clamp(3rem, 10vw, 7rem); letter-spacing: -.07em; }
.sp-404 p { color: var(--sp-muted); }

@media (max-width: 860px) {
  .sp-nav-toggle { display: inline-flex; align-items: center; gap: 8px; }
  .sp-primary-nav { position: absolute; top: 72px; left: 20px; right: 20px; display: none; padding: 16px; background: #fff; border: 1px solid var(--sp-border); border-radius: 14px; box-shadow: var(--sp-shadow); }
  .sp-primary-nav[data-open] { display: block; }
  .sp-primary-nav ul { align-items: stretch; flex-direction: column; gap: 0; }
  .sp-primary-nav a { display: flex; min-height: 44px; align-items: center; padding-inline: 10px; }
  .sp-case-grid, .sp-footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .sp-card-grid, .sp-post-grid { grid-template-columns: 1fr 1fr; }
  .sp-footer-bottom { align-items: flex-start; flex-direction: column; }
}

@media (max-width: 620px) {
  body { font-size: 16px; }
  .sp-container, .sp-narrow { width: min(calc(100% - 28px), var(--sp-container)); }
  .sp-hero { padding: 52px 0 22px; }
  .sp-hero h1 { font-size: clamp(2.5rem, 13vw, 4rem); }
  .sp-section { padding: 62px 0; }
  .sp-card-grid, .sp-post-grid, .sp-formula-grid, .sp-steps { grid-template-columns: 1fr; }
  .sp-card { min-height: 225px; }
  .sp-page-hero { padding: 48px 0 32px; }
  .sp-content-wrap { padding-bottom: 70px; }
  .sp-content table { display: block; overflow-x: auto; white-space: normal; }
  .sp-consent { left: 12px; right: 12px; bottom: 12px; align-items: stretch; flex-direction: column; }
  .sp-consent-actions { display: grid; grid-template-columns: 1fr 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; }
}