:root {
  --ink: #171a23;
  --muted: #62697a;
  --primary: #3157d5;
  --primary-dark: #2748b2;
  --primary-soft: #edf1ff;
  --surface: #ffffff;
  --surface-soft: #f7f8fc;
  --surface-warm: #f6f6f2;
  --border: #dfe2ea;
  --border-strong: #c8cedc;
  --success: #147a56;
  --shadow: 0 18px 55px rgba(35, 43, 75, 0.11);
  --radius-large: 24px;
  --radius-medium: 15px;
  --radius-small: 10px;
  --container: 1120px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--surface-warm);
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

button,
input {
  font: inherit;
}

button,
summary,
a {
  -webkit-tap-highlight-color: transparent;
}

button {
  color: inherit;
}

a {
  color: inherit;
}

button:focus-visible,
input:focus-visible,
summary:focus-visible,
a:focus-visible {
  outline: 3px solid rgba(49, 87, 213, 0.28);
  outline-offset: 3px;
}

.container {
  width: min(calc(100% - 40px), var(--container));
  margin-inline: auto;
}

.skip-link {
  position: absolute;
  top: -100px;
  left: 16px;
  z-index: 100;
  padding: 10px 14px;
  color: #ffffff;
  background: var(--primary);
  border-radius: 8px;
  text-decoration: none;
}

.skip-link:focus {
  top: 16px;
}

.site-header {
  position: relative;
  z-index: 10;
  border-bottom: 1px solid rgba(23, 26, 35, 0.08);
  background: rgba(246, 246, 242, 0.88);
  backdrop-filter: blur(14px);
}

.header-inner {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.brand-mark {
  position: relative;
  width: 31px;
  height: 31px;
  display: inline-block;
  flex: 0 0 auto;
  border: 3px solid var(--primary);
  border-radius: 50%;
}

.brand-mark::before,
.brand-hand {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 3px;
  height: 8px;
  content: "";
  background: var(--primary);
  border-radius: 2px;
  transform-origin: 50% 0;
}

.brand-mark::before {
  transform: translate(-50%, -1px) rotate(180deg);
}

.brand-hand {
  transform: translate(-1px, -1px) rotate(125deg);
}

.site-nav,
.site-footer nav {
  display: flex;
  align-items: center;
  gap: 24px;
}

.site-nav a,
.site-footer nav a {
  color: var(--muted);
  font-size: 0.93rem;
  font-weight: 600;
  text-decoration: none;
}

.site-nav a:hover,
.site-footer nav a:hover {
  color: var(--ink);
}

.hero {
  padding-block: 68px 36px;
  text-align: center;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--primary);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  text-wrap: pretty;
}

h1 {
  max-width: 760px;
  margin: 0 auto;
  font-size: clamp(2.35rem, 6vw, 4.4rem);
  line-height: 1.02;
  letter-spacing: -0.055em;
}

.hero-copy {
  max-width: 620px;
  margin: 22px auto 0;
  color: var(--muted);
  font-size: clamp(1rem, 2.3vw, 1.18rem);
}

.calculator-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  align-items: start;
  gap: 32px;
  padding-bottom: 82px;
}

.calculator-card {
  padding: clamp(20px, 4vw, 38px);
  background: var(--surface);
  border: 1px solid rgba(23, 26, 35, 0.08);
  border-radius: var(--radius-large);
  box-shadow: var(--shadow);
}

.mode-switch {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 6px;
  padding: 6px;
  background: var(--surface-soft);
  border: 1px solid var(--border);
  border-radius: 16px;
}

.mode-button {
  min-height: 52px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: 0;
  border-radius: 11px;
  background: transparent;
  color: var(--muted);
  font-weight: 700;
  cursor: pointer;
  transition: background 160ms ease, color 160ms ease, box-shadow 160ms ease;
}

.mode-button.is-active {
  color: #ffffff;
  background: var(--primary);
  box-shadow: 0 5px 14px rgba(49, 87, 213, 0.23);
}

.calculator-section {
  margin-top: 30px;
}

.section-heading {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 12px;
}

.section-label {
  font-weight: 750;
}

.section-note,
.summary-hint {
  color: var(--muted);
  font-size: 0.85rem;
}

.choice-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.choice-button,
.quick-button {
  min-height: 48px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface);
  font-weight: 700;
  cursor: pointer;
  transition: border-color 150ms ease, background 150ms ease, color 150ms ease, transform 150ms ease;
}

.choice-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 0 17px;
}

.choice-icon {
  color: var(--primary);
  font-size: 1.15em;
}

.choice-button:hover,
.quick-button:hover {
  border-color: var(--border-strong);
  background: var(--surface-soft);
}

.choice-button:active,
.quick-button:active,
.primary-button:active,
.secondary-button:active {
  transform: translateY(1px);
}

.choice-button.is-active,
.quick-button.is-active {
  color: var(--primary-dark);
  background: var(--primary-soft);
  border-color: rgba(49, 87, 213, 0.4);
}

.date-time-fields {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 13px;
}

.date-time-fields:not([hidden]) {
  display: grid;
}

.date-time-fields label {
  display: grid;
  gap: 6px;
  color: var(--muted);
  font-size: 0.85rem;
  font-weight: 650;
}

.date-time-fields input {
  width: 100%;
  min-height: 48px;
  padding: 9px 12px;
  color: var(--ink);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 11px;
}

.quick-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
}

.quick-button {
  padding: 8px 10px;
}

.custom-duration {
  margin-top: 22px;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.custom-duration summary {
  min-height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  font-weight: 750;
  cursor: pointer;
}

.custom-duration summary::marker {
  color: var(--primary);
}

.stepper-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 15px;
  padding: 4px 0 20px;
}

.stepper {
  display: grid;
  gap: 8px;
}

.stepper-label {
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 700;
  text-align: center;
}

.stepper-controls {
  min-height: 48px;
  display: grid;
  grid-template-columns: 44px minmax(34px, 1fr) 44px;
  align-items: center;
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
}

.stepper-controls:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(49, 87, 213, 0.14);
}

.stepper-controls button {
  align-self: stretch;
  border: 0;
  background: var(--surface-soft);
  color: var(--primary-dark);
  font-size: 1.1rem;
  font-weight: 800;
  cursor: pointer;
}

.stepper-controls button:hover {
  background: var(--primary-soft);
}

.stepper-controls input {
  width: 100%;
  min-width: 0;
  height: 100%;
  padding: 0 4px;
  color: var(--ink);
  background: transparent;
  border: 0;
  appearance: textfield;
  text-align: center;
  font-weight: 800;
  font-variant-numeric: tabular-nums;
}

.stepper-controls input:focus-visible {
  outline: 0;
}

.stepper-controls input::-webkit-inner-spin-button,
.stepper-controls input::-webkit-outer-spin-button {
  margin: 0;
  appearance: none;
}

.hold-hint {
  margin: -7px 0 18px;
  color: var(--muted);
  font-size: 0.8rem;
  text-align: center;
}

.result-panel {
  margin-top: 26px;
  padding: clamp(20px, 4vw, 30px);
  background: linear-gradient(145deg, #f0f3ff 0%, #e8eeff 100%);
  border: 1px solid rgba(49, 87, 213, 0.2);
  border-radius: 18px;
}

.result-kicker {
  margin: 0 0 3px;
  color: var(--primary-dark);
  font-size: 0.83rem;
  font-weight: 800;
  letter-spacing: 0.035em;
  text-transform: uppercase;
}

.result-primary {
  display: block;
  font-size: clamp(1.7rem, 5vw, 2.65rem);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.04em;
}

.result-full {
  min-height: 1.5em;
  margin: 7px 0 0;
  color: var(--muted);
}

.result-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

.primary-button,
.secondary-button {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 9px 17px;
  border-radius: 11px;
  font-weight: 750;
  cursor: pointer;
}

.primary-button {
  color: #ffffff;
  background: var(--primary);
  border: 1px solid var(--primary);
}

.primary-button:hover {
  background: var(--primary-dark);
}

.secondary-button {
  color: var(--primary-dark);
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid rgba(49, 87, 213, 0.25);
}

.secondary-button:hover {
  background: #ffffff;
}

.local-note {
  margin: 14px 0 0;
  color: var(--muted);
  font-size: 0.78rem;
  text-align: center;
}

.noscript-message {
  padding: 10px 12px;
  color: #842429;
  background: #fff0f1;
  border-radius: 10px;
}

.ad-slot {
  display: grid;
  place-content: center;
  gap: 3px;
  color: #858b98;
  background: rgba(255, 255, 255, 0.4);
  border: 1px dashed #c8ccd4;
  border-radius: 14px;
  text-align: center;
}

.ad-slot span {
  font-size: 0.66rem;
  letter-spacing: 0.12em;
}

.ad-slot strong {
  font-size: 0.78rem;
  font-weight: 600;
}

.ad-rail {
  min-height: 250px;
}

.ad-banner {
  min-height: 112px;
  margin-top: 12px;
  margin-bottom: 78px;
}

.content-section {
  padding-bottom: 90px;
}

.section-intro {
  max-width: 650px;
  margin-bottom: 35px;
}

.section-intro.compact {
  margin-bottom: 25px;
}

.section-intro h2 {
  margin: 0;
  font-size: clamp(1.8rem, 4vw, 2.7rem);
  line-height: 1.12;
  letter-spacing: -0.038em;
}

.section-intro > p:last-child {
  margin: 14px 0 0;
  color: var(--muted);
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.steps-grid article {
  padding: 24px;
  background: rgba(255, 255, 255, 0.56);
  border: 1px solid rgba(23, 26, 35, 0.08);
  border-radius: 16px;
}

.step-number {
  width: 34px;
  height: 34px;
  display: inline-grid;
  place-items: center;
  color: var(--primary-dark);
  background: var(--primary-soft);
  border-radius: 50%;
  font-size: 0.82rem;
  font-weight: 800;
}

.steps-grid h3 {
  margin: 17px 0 8px;
  font-size: 1.08rem;
}

.steps-grid p {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.popular-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.popular-grid button {
  min-height: 64px;
  padding: 13px 16px;
  color: var(--ink);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 13px;
  font-weight: 700;
  text-align: left;
  cursor: pointer;
}

.popular-grid button::after {
  float: right;
  color: var(--primary);
  content: "→";
}

.popular-grid button:hover {
  border-color: rgba(49, 87, 213, 0.4);
  background: var(--primary-soft);
}

.faq-list {
  max-width: 820px;
  border-top: 1px solid var(--border-strong);
}

.faq-list details {
  border-bottom: 1px solid var(--border-strong);
}

.faq-list summary {
  padding: 20px 4px;
  font-weight: 750;
  cursor: pointer;
}

.faq-list summary::marker {
  color: var(--primary);
}

.faq-list p {
  max-width: 700px;
  margin: -5px 0 22px;
  color: var(--muted);
}

.site-footer {
  padding-block: 44px;
  background: #1b1f2a;
  color: #ffffff;
}

.footer-inner {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: start;
  gap: 26px 40px;
}

.footer-brand {
  color: #ffffff;
}

.footer-inner > div p,
.copyright {
  margin: 8px 0 0;
  color: #aeb5c5;
  font-size: 0.88rem;
}

.site-footer nav a {
  color: #cbd0dc;
}

.copyright {
  grid-column: 1 / -1;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
}

.legal-main {
  min-height: calc(100vh - 270px);
  padding-block: 64px 90px;
}

.legal-card {
  max-width: 780px;
  padding: clamp(24px, 5vw, 52px);
  background: var(--surface);
  border: 1px solid rgba(23, 26, 35, 0.08);
  border-radius: var(--radius-large);
  box-shadow: var(--shadow);
}

.legal-card h1 {
  margin: 0;
  font-size: clamp(2.1rem, 6vw, 3.5rem);
  text-align: left;
}

.legal-card h2 {
  margin: 34px 0 10px;
  font-size: 1.25rem;
}

.legal-card p,
.legal-card li {
  color: var(--muted);
}

.legal-card .updated {
  margin: 9px 0 30px;
  color: var(--muted);
  font-size: 0.87rem;
}

.legal-card a {
  color: var(--primary-dark);
}

@media (max-width: 900px) {
  .calculator-layout {
    grid-template-columns: 1fr;
  }

  .ad-rail {
    min-height: 112px;
  }
}

@media (max-width: 650px) {
  .container {
    width: min(calc(100% - 28px), var(--container));
  }

  .header-inner {
    min-height: 64px;
  }

  .site-nav a:not(:last-child) {
    display: none;
  }

  .hero {
    padding-block: 48px 27px;
  }

  .calculator-layout {
    gap: 22px;
    padding-bottom: 65px;
  }

  .calculator-card {
    border-radius: 19px;
  }

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

  .date-time-fields,
  .stepper-grid {
    grid-template-columns: 1fr;
  }

  .stepper {
    grid-template-columns: 70px 1fr;
    align-items: center;
  }

  .stepper-label {
    text-align: left;
  }

  .result-actions > button {
    width: 100%;
  }

  .steps-grid,
  .popular-grid {
    grid-template-columns: 1fr;
  }

  .content-section {
    padding-bottom: 68px;
  }

  .ad-banner {
    margin-bottom: 66px;
  }

  .footer-inner {
    grid-template-columns: 1fr;
  }

  .copyright {
    grid-column: auto;
  }
}

@media (max-width: 390px) {
  .mode-button {
    gap: 4px;
    font-size: 0.91rem;
  }

  .choice-row {
    display: grid;
    grid-template-columns: 1fr;
  }

  .section-heading {
    align-items: flex-start;
    flex-direction: column;
    gap: 2px;
  }
}

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

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
  }
}