/* =============================================================
   CalcHub — Design System v3.1
   Multi-page static architecture · SEO-first
   Mobile-first · Navy + Teal · DM Sans
   ============================================================= */

@import url('https://fonts.googleapis.com/css2?family=DM+Sans:ital,opsz,wght@0,9..40,300;0,9..40,400;0,9..40,600;0,9..40,700;1,9..40,400&family=DM+Mono:wght@400;500&display=swap');

/* ── Variables ─────────────────────────────────────────────── */
:root {
  --navy: #0d1b2a;
  --navy-mid: #1b2d3e;
  --navy-soft: #243447;
  --teal: #00c9a7;
  --teal-dim: #009d82;
  --teal-glow: rgba(0, 201, 167, 0.15);
  --sky: #3b9eff;
  --amber: #f59e0b;
  --red: #ef4444;
  --white: #f8fafb;
  --text: #e8eef4;
  --text-dim: #8fa3b8;
  --card-bg: rgba(27, 45, 62, 0.85);
  --card-bdr: rgba(0, 201, 167, 0.14);
  --card-bdr-strong: rgba(0, 201, 167, 0.28);
  --input-bg: rgba(13, 27, 42, 0.7);
  --overlay: rgba(13, 27, 42, 0.96);
  --radius: 14px;
  --radius-sm: 8px;
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.35);
  --shadow-soft: 0 10px 30px rgba(0, 0, 0, 0.22);
  --transition: 0.22s cubic-bezier(0.4, 0, 0.2, 1);
  --font: 'DM Sans', system-ui, sans-serif;
  --mono: 'DM Mono', monospace;
  --content-w: 760px;
  --layout-w: 1100px;
  --header-h: 72px;
}

/* ── Reset ─────────────────────────────────────────────────── */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font);
  background: var(--navy);
  color: var(--text);
  min-height: 100dvh;
  line-height: 1.7;
  overflow-x: hidden;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background:
    radial-gradient(ellipse 80% 50% at 10% 15%, rgba(0, 201, 167, 0.07) 0%, transparent 60%),
    radial-gradient(ellipse 60% 40% at 90% 80%, rgba(59, 158, 255, 0.06) 0%, transparent 60%);
}

img,
svg,
canvas,
video {
  max-width: 100%;
  display: block;
}

button,
input,
select,
textarea {
  font: inherit;
}

button {
  -webkit-tap-highlight-color: transparent;
}

ul,
ol {
  list-style-position: outside;
}

/* ── Typography ────────────────────────────────────────────── */
h1 {
  font-size: clamp(1.7rem, 5vw, 2.6rem);
  line-height: 1.15;
  font-weight: 700;
  color: var(--white);
}

h2 {
  font-size: clamp(1.2rem, 3vw, 1.65rem);
  line-height: 1.25;
  font-weight: 700;
  color: var(--white);
}

h3 {
  font-size: 1.1rem;
  line-height: 1.3;
  font-weight: 600;
  color: var(--white);
}

h4 {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--white);
}

p {
  color: var(--text-dim);
}

p + p {
  margin-top: 0.75rem;
}

strong {
  color: var(--text);
  font-weight: 600;
}

a {
  color: var(--teal);
  text-decoration: none;
  transition:
    color var(--transition),
    border-color var(--transition),
    background-color var(--transition),
    transform var(--transition);
}

a:hover {
  color: var(--sky);
}

/* ── Layout ────────────────────────────────────────────────── */
.container {
  width: 100%;
  max-width: var(--layout-w);
  margin: 0 auto;
  padding: 0 18px;
}

.content-wrap {
  max-width: var(--content-w);
  margin: 0 auto;
}

.page-wrap {
  position: relative;
  z-index: 1;
  min-height: 100dvh;
}

/* ── Header ────────────────────────────────────────────────── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(13, 27, 42, 0.94);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--card-bdr);
}

.header-inner {
  min-height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.site-logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.12rem;
  color: var(--white);
  flex-shrink: 0;
}

.site-logo:hover {
  color: var(--teal);
}

.logo-mark {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  flex-shrink: 0;
  background: linear-gradient(135deg, var(--teal), var(--sky));
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  color: #fff;
  box-shadow: 0 8px 24px rgba(0, 201, 167, 0.22);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.site-nav-link,
.site-nav a {
  padding: 8px 12px;
  border-radius: 8px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-dim);
  transition: var(--transition);
}

.site-nav-link:hover,
.site-nav a:hover,
.site-nav-link[aria-current='page'],
.site-nav a[aria-current='page'],
.site-nav-link.is-active {
  background: var(--teal-glow);
  color: var(--teal);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text);
  font-size: 1.4rem;
  cursor: pointer;
  padding: 6px;
  border-radius: 8px;
}

.nav-toggle:hover {
  background: rgba(255, 255, 255, 0.04);
}

.mobile-nav[hidden] {
  display: none !important;
}

.mobile-nav {
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  background: rgba(13, 27, 42, 0.98);
}

.mobile-nav-inner {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 16px 0 20px;
}

.mobile-nav-inner a {
  display: block;
  padding: 10px 12px;
  border-radius: 10px;
  color: var(--text-dim);
  font-weight: 600;
}

.mobile-nav-inner a:hover,
.mobile-nav-inner a[aria-current='page'],
.mobile-nav-inner a.is-active {
  background: var(--teal-glow);
  color: var(--teal);
}

/* ── Ad Banner ─────────────────────────────────────────────── */
.ad-leaderboard {
  background: rgba(13, 27, 42, 0.42);
  border-bottom: 1px solid rgba(0, 201, 167, 0.08);
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 52px;
  padding: 4px 16px;
}

.ad-leaderboard-top {
  transition: none;
}

.ad-slot {
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(255, 255, 255, 0.03);
  border: 1px dashed rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-sm);
  color: var(--text-dim);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  overflow: hidden;
}

.ad-slot-728x90 {
  width: 100%;
  max-width: 728px;
  min-height: 50px;
  max-height: 90px;
}

.ad-slot-300x250 {
  width: 300px;
  height: 250px;
}

.ad-slot-responsive {
  width: 100%;
  min-height: 90px;
}

/* ── Breadcrumb ────────────────────────────────────────────── */
.breadcrumb {
  padding: 10px 0;
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
  font-size: 0.8rem;
  color: var(--text-dim);
}

.breadcrumb a {
  color: var(--text-dim);
}

.breadcrumb a:hover {
  color: var(--teal);
}

.breadcrumb span {
  opacity: 0.7;
}

/* ── Hero calcolatore / articolo ───────────────────────────── */
.calc-hero,
.article-hero {
  padding: 36px 0 28px;
  border-bottom: 1px solid var(--card-bdr);
  margin-bottom: 32px;
}

.calc-hero h1,
.article-hero h1 {
  margin-bottom: 10px;
}

.hero-desc {
  font-size: 1.03rem;
  max-width: 700px;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 16px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 4px 12px;
  border-radius: 50px;
  font-size: 0.75rem;
  font-weight: 700;
  background: var(--teal-glow);
  border: 1px solid rgba(0, 201, 167, 0.25);
  color: var(--teal);
}

/* ── Layout calcolatore ────────────────────────────────────── */
.calc-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  margin-bottom: 48px;
}

@media (min-width: 900px) {
  .calc-layout {
    grid-template-columns: 380px 1fr;
    align-items: start;
  }
}

/* ── Card ──────────────────────────────────────────────────── */
.card {
  background: var(--card-bg);
  border: 1px solid var(--card-bdr);
  border-radius: var(--radius);
  padding: 22px 20px;
  backdrop-filter: blur(8px);
  box-shadow: var(--shadow-soft);
}

.card-title {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--teal);
  margin-bottom: 18px;
}

.card-sticky {
  position: sticky;
  top: 90px;
}

/* ── Form ──────────────────────────────────────────────────── */
.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.field + .field {
  margin-top: 14px;
}

label {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-dim);
}

input[type='number'],
input[type='text'],
input[type='email'],
input[type='url'],
select,
textarea {
  width: 100%;
  background: var(--input-bg);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-sm);
  color: var(--white);
  font-family: var(--font);
  font-size: 1rem;
  padding: 10px 14px;
  transition: var(--transition);
  -webkit-appearance: none;
  appearance: none;
}

input::placeholder,
textarea::placeholder {
  color: rgba(143, 163, 184, 0.7);
}

input:focus,
select:focus,
textarea:focus {
  outline: none;
  border-color: var(--teal);
  box-shadow: 0 0 0 3px rgba(0, 201, 167, 0.15);
}

textarea {
  min-height: 120px;
  resize: vertical;
}

select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%2300c9a7' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 14px center;
  padding-right: 36px;
}

/* Range */
input[type='range'] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 5px;
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.12);
  cursor: pointer;
}

input[type='range']::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--teal);
  box-shadow: 0 0 0 3px rgba(0, 201, 167, 0.2);
  transition: var(--transition);
}

input[type='range']::-webkit-slider-thumb:hover {
  transform: scale(1.12);
}

input[type='range']::-moz-range-thumb {
  width: 20px;
  height: 20px;
  border: none;
  border-radius: 50%;
  background: var(--teal);
  box-shadow: 0 0 0 3px rgba(0, 201, 167, 0.2);
  transition: var(--transition);
}

.slider-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}

.slider-val {
  font-family: var(--mono);
  font-size: 0.9rem;
  color: var(--teal);
  font-weight: 500;
}

/* ── Buttons ───────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  padding: 11px 22px;
  border-radius: var(--radius-sm);
  border: none;
  font-family: var(--font);
  font-size: 0.9rem;
  font-weight: 700;
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
  text-decoration: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--teal), #009d82);
  color: #fff;
  width: 100%;
  margin-top: 18px;
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(0, 201, 167, 0.3);
  color: #fff;
}

.btn-secondary {
  background: var(--teal-glow);
  border: 1px solid rgba(0, 201, 167, 0.3);
  color: var(--teal);
}

.btn-secondary:hover {
  background: rgba(0, 201, 167, 0.2);
  color: var(--teal);
}

.btn-sm {
  padding: 7px 14px;
  font-size: 0.8rem;
}

.btn-group {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 14px;
}

/* ── Risultati ─────────────────────────────────────────────── */
.result-hero-box {
  background: rgba(0, 201, 167, 0.07);
  border: 1px solid rgba(0, 201, 167, 0.22);
  border-radius: var(--radius);
  padding: 18px 20px;
  margin-bottom: 14px;
}

.result-label {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dim);
  margin-bottom: 4px;
}

.result-value {
  font-family: var(--mono);
  font-size: clamp(1.6rem, 5vw, 2.2rem);
  color: var(--teal);
  font-weight: 500;
  line-height: 1.1;
}

.kpi-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: 10px;
}

.kpi {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius-sm);
  padding: 12px;
}

.kpi-value {
  font-family: var(--mono);
  font-size: 1.05rem;
  color: var(--white);
  font-weight: 500;
}

.kpi-label {
  font-size: 0.72rem;
  color: var(--text-dim);
  margin-top: 2px;
}

.chart-wrap {
  position: relative;
  width: 100%;
  height: 260px;
}

/* ── Sezioni ───────────────────────────────────────────────── */
.section {
  padding: 28px 0 40px;
  border-top: 1px solid var(--card-bdr);
}

.section-title {
  margin-bottom: 16px;
}

.section-intro {
  font-size: 1rem;
  margin-bottom: 24px;
}

/* ── Steps / benefits ──────────────────────────────────────── */
.steps-grid,
.benefit-grid {
  display: grid;
  gap: 14px;
  margin-top: 20px;
}

.steps-grid {
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

.benefit-grid {
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
}

.step-card,
.benefit-item {
  background: var(--card-bg);
  border: 1px solid var(--card-bdr);
  border-radius: var(--radius);
  padding: 18px;
  box-shadow: var(--shadow-soft);
}

.step-num {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--teal-glow);
  border: 1px solid rgba(0, 201, 167, 0.3);
  color: var(--teal);
  font-weight: 700;
  font-size: 0.85rem;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 10px;
}

.step-card h3,
.benefit-item h3 {
  margin-bottom: 6px;
  font-size: 1rem;
}

.bi-icon {
  font-size: 1.6rem;
  margin-bottom: 8px;
}

.benefit-item {
  text-align: center;
}

.benefit-item p {
  font-size: 0.78rem;
}

/* ── FAQ ───────────────────────────────────────────────────── */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

details.faq-item {
  background: var(--card-bg);
  border: 1px solid var(--card-bdr);
  border-radius: var(--radius);
  overflow: hidden;
}

details.faq-item summary {
  padding: 16px 18px;
  cursor: pointer;
  font-weight: 600;
  color: var(--white);
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  transition: background var(--transition);
}

details.faq-item summary::-webkit-details-marker {
  display: none;
}

details.faq-item summary::after {
  content: '+';
  color: var(--teal);
  font-size: 1.2rem;
  font-weight: 400;
  flex-shrink: 0;
}

details.faq-item[open] summary::after {
  content: '−';
}

details.faq-item summary:hover {
  background: rgba(0, 201, 167, 0.05);
}

.faq-body {
  padding: 0 18px 16px;
}

.faq-body p {
  font-size: 0.92rem;
}

/* ── Correlati ─────────────────────────────────────────────── */
.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 12px;
  margin-top: 16px;
}

.related-card {
  display: flex;
  flex-direction: column;
  gap: 4px;
  background: var(--card-bg);
  border: 1px solid var(--card-bdr);
  border-radius: var(--radius);
  padding: 16px 18px;
  transition: var(--transition);
  text-decoration: none;
  box-shadow: var(--shadow-soft);
}

.related-card:hover {
  border-color: rgba(0, 201, 167, 0.4);
  background: rgba(27, 45, 62, 0.95);
  transform: translateY(-2px);
}

.related-icon {
  font-size: 1.4rem;
  margin-bottom: 4px;
}

.related-name {
  font-weight: 700;
  color: var(--white);
  font-size: 0.92rem;
}

.related-desc {
  font-size: 0.78rem;
  color: var(--text-dim);
}

/* ── Home ──────────────────────────────────────────────────── */
.home-hero {
  padding: 60px 0 48px;
  text-align: center;
}

.home-hero h1 {
  margin-bottom: 14px;
}

.home-hero p {
  font-size: 1.1rem;
  max-width: 640px;
  margin: 0 auto 28px;
}

.calc-grid-home {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 14px;
  margin-top: 8px;
}

.calc-card-home {
  display: flex;
  flex-direction: column;
  background: var(--card-bg);
  border: 1px solid var(--card-bdr);
  border-radius: var(--radius);
  padding: 20px 18px;
  text-decoration: none;
  transition: var(--transition);
  box-shadow: var(--shadow-soft);
}

.calc-card-home:hover {
  border-color: rgba(0, 201, 167, 0.4);
  transform: translateY(-3px);
  box-shadow: var(--shadow);
}

.calc-icon {
  font-size: 1.8rem;
  margin-bottom: 10px;
}

.calc-name {
  font-weight: 700;
  color: var(--white);
  font-size: 1rem;
  margin-bottom: 4px;
}

.calc-teaser {
  font-size: 0.8rem;
  color: var(--text-dim);
}

.home-section {
  padding: 48px 0;
  border-top: 1px solid var(--card-bdr);
}

.home-section h2 {
  margin-bottom: 8px;
}

/* ── Article body ──────────────────────────────────────────── */
.article-body {
  max-width: var(--content-w);
  margin: 0 auto;
}

.article-body h2 {
  margin-top: 32px;
  margin-bottom: 12px;
}

.article-body h3 {
  margin-top: 24px;
  margin-bottom: 10px;
}

.article-body p,
.article-body ul,
.article-body ol,
.article-body details,
.article-body blockquote {
  margin-bottom: 14px;
}

.article-body ul,
.article-body ol {
  padding-left: 22px;
}

.article-body li {
  color: var(--text-dim);
  margin-bottom: 5px;
  font-size: 0.95rem;
}

.article-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 18px 0;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--card-bdr);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.article-body th,
.article-body td {
  text-align: left;
  padding: 12px 14px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  color: var(--text-dim);
}

.article-body th {
  color: var(--white);
  background: rgba(255, 255, 255, 0.03);
}

.article-body blockquote {
  padding: 14px 16px;
  border-left: 3px solid var(--teal);
  background: rgba(0, 201, 167, 0.06);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.article-cta {
  background: var(--teal-glow);
  border: 1px solid rgba(0, 201, 167, 0.25);
  border-radius: var(--radius);
  padding: 20px 22px;
  margin: 28px 0;
}

.article-cta p {
  color: var(--text);
  font-size: 0.95rem;
}

.article-cta .btn {
  margin-top: 12px;
  width: auto;
}

/* ── Footer ────────────────────────────────────────────────── */
.site-footer {
  background: rgba(13, 27, 42, 0.9);
  border-top: 1px solid var(--card-bdr);
  padding: 40px 0 24px;
  margin-top: 60px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr repeat(3, 1fr);
  gap: 32px;
  margin-bottom: 32px;
}

.footer-brand p {
  font-size: 0.82rem;
  margin-top: 10px;
  max-width: 280px;
}

.footer-col h4 {
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 12px;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 7px;
}

.footer-col ul a {
  font-size: 0.82rem;
  color: var(--text-dim);
}

.footer-col ul a:hover {
  color: var(--teal);
}

.footer-bottom {
  border-top: 1px solid var(--card-bdr);
  padding-top: 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 0.75rem;
  color: var(--text-dim);
}

/* ── 404 ───────────────────────────────────────────────────── */
.page-404 {
  min-height: 70vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  gap: 16px;
}

.page-404 h1 {
  font-size: clamp(4rem, 15vw, 8rem);
  color: var(--teal);
  line-height: 1;
}

/* ── Toast ─────────────────────────────────────────────────── */
.toast {
  position: fixed;
  bottom: 24px;
  right: 16px;
  z-index: 9999;
  background: var(--navy-soft);
  border: 1px solid var(--teal);
  color: var(--white);
  border-radius: var(--radius-sm);
  padding: 12px 18px;
  font-size: 0.88rem;
  transform: translateY(60px);
  opacity: 0;
  transition: var(--transition);
  pointer-events: none;
  box-shadow: var(--shadow);
}

.toast.show {
  transform: translateY(0);
  opacity: 1;
}

/* ── Utility ───────────────────────────────────────────────── */
.hidden {
  display: none !important;
}

.mt-8 {
  margin-top: 8px;
}

.mt-12 {
  margin-top: 12px;
}

.mt-16 {
  margin-top: 16px;
}

.mt-24 {
  margin-top: 24px;
}

.text-teal {
  color: var(--teal);
}

.text-dim {
  color: var(--text-dim);
}

.text-white {
  color: var(--white);
}

.mono {
  font-family: var(--mono);
}

/* ── Scrollbar ─────────────────────────────────────────────── */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: rgba(0, 201, 167, 0.3);
  border-radius: 3px;
}

/* ── Responsive ────────────────────────────────────────────── */
@media (max-width: 960px) {
  .site-nav {
    display: none;
  }

  .nav-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

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

  .card-sticky {
    position: static;
  }
}

@media (max-width: 640px) {
  .container {
    padding: 0 14px;
  }

  .site-header {
    backdrop-filter: blur(10px);
  }

  .header-inner {
    min-height: 60px;
  }

  .ad-leaderboard-top {
    display: none !important;
  }

  .home-hero {
    padding: 46px 0 34px;
  }

  .calc-hero,
  .article-hero {
    padding: 28px 0 22px;
    margin-bottom: 24px;
  }

  .hero-desc {
    font-size: 0.98rem;
  }

  .card {
    padding: 18px 16px;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }

  .calc-layout {
    gap: 18px;
  }

  .chart-wrap {
    height: 220px;
  }

  .related-grid,
  .calc-grid-home,
  .steps-grid,
  .benefit-grid {
    grid-template-columns: 1fr;
  }

  .result-value {
    font-size: 1.8rem;
  }

  .article-body table,
  .article-body thead,
  .article-body tbody,
  .article-body th,
  .article-body td,
  .article-body tr {
    display: block;
  }

  .article-body thead {
    display: none;
  }

  .article-body tr {
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    padding: 8px 0;
  }

  .article-body td {
    padding: 8px 0;
    border-bottom: none;
  }
}