*{ box-sizing:border-box; margin:0; padding:0; }
html{ scroll-behavior:smooth; }
body{ font-family:var(--font-body); color:var(--ink); background:var(--bg); -webkit-font-smoothing:antialiased; }
a{ color:inherit; text-decoration:none; }
h1,h2,h3{ font-family:var(--font-display); letter-spacing:-0.01em; }
.mono{ font-family:var(--font-mono); }
button{ font-family:inherit; cursor:pointer; }
:focus-visible{ outline:2px solid var(--blue); outline-offset:2px; }

.skip-link{
  position:absolute; left:-9999px; top:0; z-index:200; background:var(--ink); color:#fff;
  padding:0.75rem 1.25rem; border-radius:0 0 8px 0; font-weight:600; font-size:0.9rem; text-decoration:none;
}
.skip-link:focus{ left:0; }

/* ---------- HEADER ---------- */
.header-accent{ height:3px; background:linear-gradient(90deg, var(--blue) 0%, var(--blue-deep) 50%, var(--accent) 100%); }
header{ background:var(--card); border-bottom:1px solid var(--line); box-shadow:0 1px 3px rgba(16,24,40,0.04); position:sticky; top:0; z-index:60; }
.header-inner{ display:flex; align-items:center; justify-content:space-between; padding:14px 24px; max-width:1200px; margin:0 auto; gap:20px; }
.logo-block{ display:flex; align-items:center; gap:10px; flex:none; text-decoration:none; }
.logo-mark{ width:34px; height:34px; border-radius:9px; background:linear-gradient(135deg, var(--blue) 0%, var(--blue-deep) 100%); display:flex; align-items:center; justify-content:center; box-shadow:0 4px 10px rgba(30,62,125,0.25); overflow:hidden; }
.logo-mark span{ color:#fff; font-family:var(--font-display); font-weight:700; font-size:15px; }
.logo-mark img{ width:100%; height:100%; object-fit:contain; }
.logo-text{ font-family:var(--font-display); font-size:18px; font-weight:700; color:var(--ink); line-height:1.1; }
.logo-text small{ display:block; font-family:var(--font-body); font-size:10px; font-weight:500; color:var(--ink-faint); letter-spacing:0.02em; }

nav.main-nav{ display:flex; align-items:center; gap:4px; flex:none; }
.plain-link{ font-size:13.5px; font-weight:500; color:var(--ink-soft); padding:9px 13px; border-radius:8px; position:relative; }
.plain-link:hover{ color:var(--blue-deep); background:var(--blue-pale); }
.nav-item{ position:relative; }
.nav-item > button{ background:none; border:none; font-size:13.5px; font-weight:500; color:var(--ink-soft); padding:9px 13px; display:flex; align-items:center; gap:5px; border-radius:8px; }
.nav-item > button:hover{ color:var(--blue-deep); background:var(--blue-pale); }
.nav-item > button svg{ width:10px; height:10px; transition:transform .15s; }
.nav-item.open > button svg{ transform:rotate(180deg); }
.mega{ display:none; position:absolute; top:calc(100% + 10px); left:0; background:var(--card); border:1px solid var(--line); border-radius:12px; box-shadow:0 18px 40px rgba(16,24,40,0.14); padding:8px; width:270px; }
.nav-item.open .mega{ display:block; }
.mega a{ display:flex; justify-content:space-between; align-items:center; padding:9px 10px; border-radius:7px; font-size:13px; color:var(--ink); }
.mega a:hover{ background:var(--blue-pale); color:var(--blue-deep); }
.mega a .cnt{ font-size:10.5px; color:var(--ink-faint); font-family:var(--font-mono); }

.header-search{ display:flex; align-items:center; gap:0; border:1.5px solid var(--line); background:var(--card); padding:4px 16px 4px 4px; border-radius:100px; width:240px; flex:none; transition:border-color .15s, box-shadow .15s, width .2s; }
.header-search:focus-within{ border-color:var(--blue); box-shadow:0 0 0 4px var(--blue-pale); width:270px; }
.header-search .icon-circle{ width:30px; height:30px; border-radius:50%; background:var(--blue-pale); display:flex; align-items:center; justify-content:center; flex:none; margin-right:8px; }
.header-search .icon-circle svg{ width:14px; height:14px; color:var(--blue-deep); }
.header-search input{ border:none; outline:none; background:transparent; font-size:13px; color:var(--ink); width:100%; }
.header-search input::placeholder{ color:var(--ink-faint); }

.site-search-wrap{ position:relative; }
.search-results{
  position:absolute; top:calc(100% + 6px); left:0; right:0; background:var(--card);
  border:1px solid var(--line); border-radius:10px; box-shadow:0 18px 40px rgba(16,24,40,0.14);
  max-height:320px; overflow-y:auto; z-index:50;
}
.search-results a{ display:flex; justify-content:space-between; align-items:center; padding:10px 14px; font-size:13.5px; color:var(--ink); border-bottom:1px solid var(--line); }
.search-results a:last-child{ border-bottom:none; }
.search-results a:hover{ background:var(--blue-pale); color:var(--blue-deep); }
.search-results a .cat{ font-size:11px; color:var(--ink-faint); }
.search-results .empty{ padding:14px; font-size:13px; color:var(--ink-soft); }

.header-actions{ display:flex; align-items:center; gap:9px; flex:none; }
.lang-switch{ position:relative; }
.lang-btn{ display:flex; align-items:center; gap:6px; font-size:13px; font-weight:600; color:var(--ink); border:1.5px solid var(--line); background:var(--card); padding:8px 12px; border-radius:9px; }
.lang-btn:hover{ border-color:var(--blue); }
.lang-btn svg{ width:10px; height:10px; }
.lang-menu{ display:none; position:absolute; right:0; top:calc(100% + 8px); background:var(--card); border:1px solid var(--line); border-radius:10px; box-shadow:0 12px 32px rgba(16,24,40,0.14); overflow:hidden; min-width:150px; z-index:10; }
.lang-menu.open{ display:block; }
.lang-menu a{ display:flex; justify-content:space-between; padding:10px 14px; font-size:13px; color:var(--ink); }
.lang-menu a:hover{ background:var(--blue-pale); }
.lang-menu a .tag{ color:var(--ink-faint); font-size:11px; font-family:var(--font-mono); }
.hamburger{ display:none; }

/* ---------- HERO ---------- */
.hero{ background:var(--card); position:relative; overflow:hidden; padding:56px 24px 0; border-bottom:1px solid var(--line); }
.hero .grid-lines{ position:absolute; inset:0; background-image:repeating-linear-gradient(0deg, var(--line) 0, var(--line) 1px, transparent 1px, transparent 44px), repeating-linear-gradient(90deg, var(--line) 0, var(--line) 1px, transparent 1px, transparent 44px); opacity:0.5; mask-image:radial-gradient(circle at 30% 20%, black 0%, black 10%, transparent 60%); }
.hero-grid{ position:relative; z-index:2; max-width:1180px; margin:0 auto; display:grid; grid-template-columns:1.1fr 0.9fr; gap:48px; align-items:center; padding-bottom:52px; }

.hero-eyebrow{ display:inline-flex; align-items:center; gap:7px; font-size:12px; font-weight:600; color:var(--blue-deep); background:var(--blue-pale); padding:6px 14px; border-radius:100px; margin-bottom:20px; }
.hero-eyebrow .dot{ width:5px; height:5px; border-radius:50%; background:#12805C; }
.hero h1{ font-size:clamp(1.8rem, 4.2vw, 2.9rem); font-weight:700; color:var(--ink); line-height:1.12; }
.hero h1 .accent{ color:var(--blue-deep); }
.hero p.sub{ margin-top:16px; font-size:15px; color:var(--ink-soft); max-width:460px; line-height:1.65; }

.search-box{ margin-top:26px; max-width:460px; display:flex; align-items:center; gap:10px; background:var(--card); border:1px solid var(--line); box-shadow:0 12px 26px rgba(16,24,40,0.06); border-radius:11px; padding:5px 5px 5px 16px; }
.search-box svg{ width:17px; height:17px; color:var(--ink-faint); flex:none; }
.search-box input{ border:none; outline:none; flex:1; font-size:14px; color:var(--ink); padding:11px 0; background:transparent; min-width:0; }
.search-box input::placeholder{ color:var(--ink-faint); }
.search-box button{ background:var(--accent-deep); color:#fff; border:none; font-weight:700; font-size:13px; padding:11px 18px; border-radius:7px; flex:none; }
.search-box button:hover{ background:#A63E15; }

.quick-pills{ margin-top:16px; display:flex; gap:8px; flex-wrap:wrap; }
.pill{ font-size:12.5px; font-weight:600; color:var(--ink-soft); background:var(--card-alt); border:1px solid var(--line); padding:8px 15px; border-radius:100px; }
.pill:hover{ border-color:var(--blue); color:var(--blue-deep); }

/* Hero scientific calculator */
.calc-widget{ width:100%; max-width:360px; margin:0 auto; background:var(--card); border:1px solid var(--line); border-radius:18px; padding:16px; box-shadow:0 24px 50px rgba(16,24,40,0.1); }
.calc-screen{ background:var(--card-alt); border:1px solid var(--line); border-radius:12px; padding:clamp(14px,4vw,20px) 16px; text-align:right; margin-bottom:12px; }
.calc-screen .prev{ font-size:11.5px; color:var(--ink-faint); font-family:var(--font-mono); min-height:14px; }
.calc-screen .cur{ font-size:clamp(24px,7vw,30px); font-weight:700; color:var(--ink); font-family:var(--font-mono); margin-top:4px; word-break:break-all; }
.calc-sci-row{ display:grid; grid-template-columns:repeat(5, 1fr); gap:6px; margin-bottom:6px; }
.calc-sci-row button{ background:var(--blue-pale); border:1px solid var(--line); color:var(--blue-deep); font-size:clamp(10px,2.6vw,11.5px); font-weight:600; padding:clamp(7px,2vw,10px) 0; border-radius:7px; font-family:var(--font-mono); }
.calc-sci-row button:hover{ background:#D6E3F7; }
.calc-pad{ display:grid; grid-template-columns:repeat(4, 1fr); gap:8px; }
.calc-pad button{ background:var(--card-alt); border:1px solid var(--line); color:var(--ink); font-size:clamp(13px,3.6vw,15px); font-weight:600; padding:clamp(10px,3vw,14px) 0; border-radius:9px; font-family:var(--font-mono); }
.calc-pad button:hover{ background:#E5E9F0; }
.calc-pad button.op{ background:var(--accent-deep); color:#fff; border-color:var(--accent-deep); }
.calc-pad button.op:hover{ background:#A63E15; }
.calc-pad button.fn{ background:var(--blue-pale); color:var(--blue-deep); }
.calc-pad button.zero{ grid-column:span 2; }

/* Ruler divider */
.ruler{ position:relative; z-index:2; max-width:1180px; margin:0 auto; padding:0 24px; }
.ruler svg{ width:100%; height:22px; display:block; color:var(--line); }

/* Stat row */
.stat-row{ background:var(--card-alt); border-bottom:1px solid var(--line); padding:22px 24px; }
.stat-inner{ max-width:900px; margin:0 auto; display:flex; justify-content:center; }
.stat-item{ flex:1; text-align:center; padding:0 18px; border-left:1px solid var(--line); }
.stat-item:first-child{ border-left:none; }
.stat-item .num{ font-family:var(--font-display); font-weight:700; font-size:19px; color:var(--ink); }
.stat-item .lbl{ font-size:11.5px; color:var(--ink-soft); margin-top:2px; }

/* ---------- SECTIONS ---------- */
section{ padding:56px 24px; }
.section-head{ display:flex; justify-content:space-between; align-items:flex-end; max-width:1180px; margin:0 auto 30px; gap:20px; flex-wrap:wrap; }
.section-head .eyebrow{ font-size:11px; letter-spacing:0.14em; text-transform:uppercase; color:var(--blue-deep); font-weight:600; margin-bottom:8px; }
.section-head h2{ font-size:24px; font-weight:700; color:var(--ink); }
.section-head p{ margin-top:6px; color:var(--ink-soft); font-size:13.5px; max-width:440px; }
.section-head .view-all{ font-size:13px; font-weight:600; color:var(--ink); border:1px solid var(--line); padding:9px 16px; border-radius:100px; white-space:nowrap; }
.section-head .view-all:hover{ border-color:var(--blue); color:var(--blue-deep); }
.wrap-1180{ max-width:1180px; margin:0 auto; }

/* Popular calculators */
.tool-grid{ display:grid; grid-template-columns:repeat(3, 1fr); gap:14px; }
.tool-card{ background:var(--card); border:1px solid var(--line); border-radius:12px; padding:18px; transition:border-color .15s, box-shadow .15s, transform .15s; }
.tool-card:hover{ border-color:var(--blue); box-shadow:0 14px 28px rgba(16,24,40,0.08); transform:translateY(-2px); }
.tool-top{ display:flex; justify-content:space-between; align-items:flex-start; }
.tool-badge{ width:36px; height:36px; border-radius:9px; background:var(--blue-pale); color:var(--blue-deep); font-family:var(--font-mono); font-size:11px; font-weight:700; display:flex; align-items:center; justify-content:center; }
.top-tag{ font-size:9.5px; font-weight:700; color:var(--accent-deep); background:var(--accent-pale); padding:3px 8px; border-radius:100px; letter-spacing:0.03em; }
.tool-card h4{ font-family:var(--font-body); font-size:14.5px; font-weight:600; color:var(--ink); margin-top:12px; }
.tool-card .cat{ display:block; font-size:11.5px; color:var(--ink-soft); margin-top:3px; }
.tool-use{ margin-top:12px; font-size:12px; font-weight:600; color:var(--blue-deep); }

/* Categories */
.cat-grid{ display:grid; grid-template-columns:repeat(5, 1fr); gap:12px; }
.cat-card{ background:var(--card); border:1px solid var(--line); border-radius:12px; padding:18px 16px; text-align:center; transition:transform .15s, box-shadow .15s, border-color .15s; }
.cat-card:hover{ transform:translateY(-3px); box-shadow:0 14px 28px rgba(16,24,40,0.08); border-color:var(--blue); }
.cat-icon{ width:38px; height:38px; border-radius:10px; background:var(--blue-pale); display:flex; align-items:center; justify-content:center; margin:0 auto 12px; }
.cat-icon svg{ width:18px; height:18px; color:var(--blue-deep); }
.cat-card h3{ font-size:13px; color:var(--ink); font-weight:600; font-family:var(--font-body); }
.cat-card .count{ margin-top:4px; font-size:11px; color:var(--ink-soft); }
.cat-card .desc{ margin-top:5px; font-size:10.5px; color:var(--ink-faint); line-height:1.4; }

/* Recently added */
.recent-grid{ display:grid; grid-template-columns:repeat(4, 1fr); gap:12px; }
.recent-card{ background:var(--card); border:1px solid var(--line); border-radius:10px; padding:15px; transition:border-color .15s; }
.recent-card:hover{ border-color:var(--blue); }
.recent-card .cat-mini{ font-size:10.5px; color:var(--ink-soft); }
.recent-card h5{ font-size:13px; font-weight:600; color:var(--ink); margin-top:6px; line-height:1.4; }
.new-tag{ font-size:9.5px; font-weight:700; color:#12805C; background:#E7F5EE; padding:3px 8px; border-radius:100px; }

/* About / trust */
.about-section{ background:var(--card-alt); }
.about-grid{ display:grid; grid-template-columns:repeat(4, 1fr); gap:24px; max-width:1000px; margin:0 auto; }
.about-item{ text-align:center; }
.about-icon{ width:44px; height:44px; margin:0 auto 14px; border-radius:11px; background:var(--card); border:1px solid var(--line); display:flex; align-items:center; justify-content:center; }
.about-icon svg{ width:20px; height:20px; color:var(--blue-deep); }
.about-item h3{ font-size:14.5px; color:var(--ink); font-weight:600; }
.about-item p{ font-size:12.5px; color:var(--ink-soft); margin-top:6px; line-height:1.55; }

/* FAQ accordion */
.faq-section .wrap-1180{ max-width:720px; }
.faq-item{ background:var(--card); border:1px solid var(--line); border-radius:10px; padding:2px 18px; margin-bottom:10px; }
.faq-item summary{ list-style:none; cursor:pointer; padding:16px 0; font-size:14px; font-weight:600; color:var(--ink); display:flex; justify-content:space-between; align-items:center; gap:14px; }
.faq-item summary::-webkit-details-marker{ display:none; }
.faq-icon{ font-family:var(--font-display); font-size:19px; font-weight:600; color:var(--blue-deep); transition:transform .2s; flex:none; line-height:1; }
.faq-item[open] .faq-icon{ transform:rotate(45deg); }
.faq-item p{ padding:0 0 16px; font-size:13px; color:var(--ink-soft); line-height:1.65; }

/* Newsletter + Footer */
.cta-section{ background:var(--panel); text-align:center; border-top:1px solid var(--line); }
.cta-section h2{ color:var(--ink); font-size:22px; }
.cta-section p{ color:var(--ink-soft); font-size:13.5px; margin-top:8px; }
.cta-form{ display:flex; gap:8px; max-width:400px; margin:22px auto 0; }
.cta-form input{ flex:1; padding:12px 16px; border-radius:8px; border:1px solid var(--line); background:var(--card); color:var(--ink); font-size:13px; }
.cta-form input::placeholder{ color:var(--ink-faint); }
.cta-form input:focus{ outline:none; border-color:var(--accent); }
.cta-form button{ background:var(--accent-deep); color:#fff; border:none; font-weight:700; font-size:13px; padding:0 20px; border-radius:8px; }
.cta-form button:hover{ background:#A63E15; }

footer{ background:var(--panel); color:var(--ink-soft); padding:0 24px; }
.footer-grid{ max-width:1180px; margin:0 auto; display:grid; grid-template-columns:1.7fr 1fr 1fr 1fr; gap:32px; padding:40px 0; border-top:1px solid var(--line); }
.footer-brand .logo-text{ color:var(--ink); }
.footer-brand p{ font-size:12.5px; color:var(--ink-soft); margin-top:12px; line-height:1.6; max-width:230px; }
footer h5{ font-size:11px; letter-spacing:0.1em; text-transform:uppercase; color:var(--blue-deep); margin-bottom:13px; font-weight:700; }
footer ul{ list-style:none; }
footer ul li{ margin-bottom:8px; }
footer ul li a{ font-size:12.5px; color:var(--ink-soft); }
footer ul li a:hover{ color:var(--blue-deep); }
.footer-bottom{ border-top:1px solid var(--line); padding:16px 0; max-width:1180px; margin:0 auto; display:flex; justify-content:space-between; flex-wrap:wrap; gap:10px; }
.footer-bottom p{ font-size:11.5px; color:var(--ink-faint); }

/* Cookie banner */
.cookie-banner{ position:fixed; bottom:16px; left:16px; right:16px; max-width:420px; background:var(--card); border:1px solid var(--line); border-radius:12px; padding:16px; box-shadow:0 20px 50px rgba(16,24,40,0.18); z-index:100; display:none; }
.cookie-banner.show{ display:block; }
.cookie-banner p{ font-size:12.5px; color:var(--ink-soft); line-height:1.5; }
.cookie-banner .actions{ display:flex; gap:8px; margin-top:12px; }
.cookie-banner button{ font-size:12px; font-weight:600; padding:8px 14px; border-radius:7px; border:1px solid var(--line); background:var(--card-alt); color:var(--ink); }
.cookie-banner button.accept{ background:var(--blue-deep); color:#fff; border-color:var(--blue-deep); }

/* ---------- Calculator page (widget, FAQ, related) ---------- */
main.wrap{ max-width:1180px; margin:0 auto; padding:40px 24px 56px; }
.breadcrumb-nav{ font-size:12.5px; color:var(--ink-faint); margin-bottom:1rem; }
.breadcrumb-nav a{ color:var(--ink-soft); text-decoration:none; }
.breadcrumb-nav a:hover{ color:var(--blue-deep); text-decoration:underline; }
.breadcrumb-nav .sep{ margin:0 0.4em; }
main.wrap > h1{ font-size:clamp(1.6rem, 3.4vw, 2.2rem); }
main.wrap > p.intro{ margin-top:10px; color:var(--ink-soft); font-size:14.5px; max-width:640px; line-height:1.65; }
.calculator-widget{ background:var(--card); border:1px solid var(--line); border-radius:14px; padding:22px; margin:24px 0; box-shadow:0 12px 26px rgba(16,24,40,0.06); }
.calculator-widget form{ display:grid; gap:14px; max-width:420px; }
.calculator-widget label{ display:flex; flex-direction:column; gap:6px; font-size:13px; font-weight:600; color:var(--ink-soft); }
.calculator-widget input{ padding:11px 13px; font-size:14px; border:1px solid var(--line); border-radius:8px; background:var(--card-alt); color:var(--ink); font-family:var(--font-mono); }
.calculator-widget input:focus{ outline:none; border-color:var(--blue); box-shadow:0 0 0 4px var(--blue-pale); }
.calculator-widget button{ background:var(--accent-deep); color:#fff; border:none; padding:12px; border-radius:8px; font-size:14px; font-weight:700; max-width:420px; }
.calculator-widget button:hover{ background:#A63E15; }
.calculator-widget .result{ margin-top:16px; padding:16px; background:var(--blue-pale); border-radius:10px; max-width:420px; }
.calculator-widget .result-label{ display:block; font-size:12px; color:var(--blue-deep); font-weight:600; }
.calculator-widget .result-value{ font-size:1.8rem; font-weight:700; font-family:var(--font-mono); color:var(--ink); }
.calc-error{ background:var(--accent-pale); color:var(--accent-deep); padding:12px 16px; border-radius:8px; margin-top:14px; font-size:13px; max-width:420px; }
.how-it-works{ margin:32px 0; }
.how-it-works h2{ font-size:19px; }
.how-it-works p{ margin-top:8px; color:var(--ink-soft); font-size:14px; line-height:1.7; max-width:70ch; }
.faq h2{ font-size:19px; margin-bottom:14px; }
.related{ margin:32px 0; }
.related h2{ font-size:19px; margin-bottom:12px; }
.related ul{ list-style:none; display:flex; flex-direction:column; gap:8px; }
.related li a{ display:inline-block; padding:10px 14px; background:var(--card); border:1px solid var(--line); border-radius:8px; font-size:13.5px; font-weight:600; color:var(--blue-deep); }
.related li a:hover{ border-color:var(--blue); background:var(--blue-pale); }
.calculator-list{ list-style:none; }
.calculator-list li{ padding:12px 0; border-bottom:1px solid var(--line); }
.calculator-list li a{ font-size:14.5px; font-weight:600; color:var(--blue-deep); }
.static-page-body{ margin-top:1.25rem; color:var(--ink-soft); font-size:14.5px; line-height:1.8; }
.static-page-body p{ margin-bottom:1rem; max-width:70ch; }

/* contact page */
.contact-form-card{ background:var(--card); border:1px solid var(--line); border-radius:14px; padding:22px; margin:24px 0; max-width:480px; box-shadow:0 12px 26px rgba(16,24,40,0.06); }
.contact-form-card label{ display:flex; flex-direction:column; gap:6px; font-size:13px; font-weight:600; color:var(--ink-soft); margin-bottom:14px; }
.contact-form-card input, .contact-form-card textarea{ padding:11px 13px; font-size:14px; border:1px solid var(--line); border-radius:8px; background:var(--card-alt); color:var(--ink); font-family:var(--font-body); }
.contact-form-card textarea{ min-height:120px; resize:vertical; }
.contact-form-card input:focus, .contact-form-card textarea:focus{ outline:none; border-color:var(--blue); box-shadow:0 0 0 4px var(--blue-pale); }
.contact-form-card button{ background:var(--accent-deep); color:#fff; border:none; padding:12px 20px; border-radius:8px; font-size:14px; font-weight:700; }
.contact-form-card button:hover{ background:#A63E15; }
.contact-notice{ padding:14px 16px; border-radius:8px; margin-bottom:1rem; font-size:14px; max-width:480px; }
.contact-notice.success{ background:var(--good-pale, #E7F5EE); color:var(--good, #12805C); }
.contact-notice.error{ background:var(--accent-pale); color:var(--accent-deep); }

@media (max-width:980px){
  .hero-grid{ grid-template-columns:1fr; }
  .tool-grid{ grid-template-columns:repeat(2,1fr); }
  .cat-grid{ grid-template-columns:repeat(3,1fr); }
  .recent-grid{ grid-template-columns:repeat(2,1fr); }
  .about-grid{ grid-template-columns:repeat(2,1fr); }
}
@media (max-width:860px){
  nav.main-nav, .header-search{ display:none; }
  nav.main-nav.mobile-open{
    display:flex; flex-direction:column; align-items:flex-start; gap:0;
    position:absolute; top:100%; left:0; right:0; background:var(--card);
    border-bottom:1px solid var(--line); padding:0.5rem 1.5rem 1rem; box-shadow:0 12px 24px rgba(16,24,40,0.08);
  }
  nav.main-nav.mobile-open .nav-item{ width:100%; }
  nav.main-nav.mobile-open .mega{ position:static; width:100%; box-shadow:none; border:none; padding-left:0.5rem; }
  .hamburger{ display:flex; width:36px; height:36px; border-radius:8px; border:1px solid var(--line); background:var(--card-alt); align-items:center; justify-content:center; }
  .header-inner{ position:relative; }
  .tool-grid{ grid-template-columns:1fr; }
  .cat-grid{ grid-template-columns:repeat(2,1fr); }
  .footer-grid{ grid-template-columns:1fr 1fr; }
}
@media (max-width:480px){
  .hero{ padding:40px 16px 0; }
  .calc-widget{ padding:12px; border-radius:16px; max-width:100%; }
  .calc-screen{ padding:14px 12px; margin-bottom:10px; }
  .calc-sci-row{ gap:5px; margin-bottom:5px; }
  .calc-pad{ gap:6px; }
  section{ padding:44px 16px; }
}