/* ═══════════════════════════════════════════
   МойCalc — Main Stylesheet
   Design: Editorial Precision + Warm Geometry
   Fonts: Unbounded (display) + Onest (body)
   Palette: Deep Navy + Electric Amber
   ═══════════════════════════════════════════ */

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

:root {
    /* Core palette */
    --navy-950: #0a0e1a;
    --navy-900: #0f1629;
    --navy-800: #1a2240;
    --navy-700: #243058;
    --navy-600: #2e3e70;
    --navy-500: #445280;
    --navy-400: #6272a4;
    --navy-300: #8896bf;
    --navy-200: #b8c3dd;
    --navy-100: #dfe4f0;
    --navy-50: #f0f2f8;

    /* Accent — electric amber/gold */
    --amber-500: #f59e0b;
    --amber-400: #fbbf24;
    --amber-300: #fcd34d;
    --amber-200: #fde68a;
    --amber-100: #fef3c7;
    --amber-glow: rgba(245, 158, 11, 0.15);

    /* Semantic */
    --success: #10b981;
    --danger: #ef4444;
    --info: #3b82f6;

    /* Surfaces */
    --bg-body: #f8f9fc;
    --bg-card: #ffffff;
    --bg-input: #f0f2f8;
    --bg-hero: linear-gradient(145deg, #0a0e1a 0%, #1a2240 50%, #243058 100%);

    /* Typography */
    --font-display: 'Unbounded', sans-serif;
    --font-body: 'Onest', sans-serif;

    /* Spacing */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 16px;
    --space-lg: 24px;
    --space-xl: 40px;
    --space-2xl: 64px;
    --space-3xl: 96px;

    /* Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 28px;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(10, 14, 26, 0.06);
    --shadow-md: 0 4px 16px rgba(10, 14, 26, 0.08);
    --shadow-lg: 0 8px 32px rgba(10, 14, 26, 0.12);
    --shadow-xl: 0 16px 48px rgba(10, 14, 26, 0.16);
    --shadow-glow: 0 0 40px rgba(245, 158, 11, 0.2);

    /* Transitions */
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-bounce: cubic-bezier(0.34, 1.56, 0.64, 1);
    --duration-fast: 150ms;
    --duration-normal: 300ms;
    --duration-slow: 500ms;
}

/* ─── Base ─── */
html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-body);
    font-weight: 400;
    line-height: 1.65;
    color: var(--navy-900);
    background: var(--bg-body);
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

h1, h2, h3, h4, h5 {
    font-family: var(--font-display);
    font-weight: 700;
    line-height: 1.2;
    color: var(--navy-950);
}

a {
    color: var(--navy-700);
    text-decoration: none;
    transition: color var(--duration-fast) var(--ease-out);
}
a:hover { color: var(--amber-500); }

/* ─── Animations ─── */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(24px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}
@keyframes slideDown {
    from { opacity: 0; transform: translateY(-12px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes shimmer {
    0% { background-position: -200% center; }
    100% { background-position: 200% center; }
}
@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-6px); }
}
@keyframes pulse-ring {
    0% { transform: scale(0.8); opacity: 1; }
    100% { transform: scale(1.5); opacity: 0; }
}
@keyframes countUp {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ─── Header ─── */
.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(20px) saturate(1.8);
    -webkit-backdrop-filter: blur(20px) saturate(1.8);
    border-bottom: 1px solid rgba(10, 14, 26, 0.06);
    transition: box-shadow var(--duration-normal) var(--ease-out);
}
.header--scrolled {
    box-shadow: var(--shadow-md);
}

.header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 68px;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    text-decoration: none;
}
.logo__icon {
    font-size: 28px;
    color: var(--amber-500);
    filter: drop-shadow(0 2px 4px rgba(245, 158, 11, 0.3));
    animation: float 4s ease-in-out infinite;
}
.logo__text {
    font-family: var(--font-display);
    font-weight: 900;
    font-size: 1.25rem;
    color: var(--navy-950);
    letter-spacing: -0.02em;
}
.logo__accent { color: var(--amber-500); }
.logo--footer .logo__text { color: #fff; }
.logo--footer .logo__icon { color: var(--amber-400); }

.nav {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
}
.nav__link {
    padding: 6px 14px;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--navy-600);
    border-radius: var(--radius-full);
    transition: all var(--duration-fast) var(--ease-out);
}
.nav__link:hover {
    color: var(--navy-950);
    background: var(--navy-50);
}
.nav__link--active {
    color: var(--amber-500);
    background: var(--amber-glow);
}

.burger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}
.burger span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--navy-900);
    border-radius: 2px;
    transition: all var(--duration-normal) var(--ease-out);
}

/* ─── Hero ─── */
.hero {
    background: var(--bg-hero);
    padding: var(--space-3xl) 0 var(--space-2xl);
    position: relative;
    overflow: hidden;
    margin-top: -1px;
}
.hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse 600px 400px at 20% 50%, rgba(245, 158, 11, 0.08), transparent),
        radial-gradient(ellipse 400px 300px at 80% 30%, rgba(59, 130, 246, 0.06), transparent);
    pointer-events: none;
}
.hero::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 60px;
    background: linear-gradient(to top, var(--bg-body), transparent);
    pointer-events: none;
}

.hero__content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 720px;
    margin: 0 auto;
}

.hero__badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    padding: 6px 16px;
    background: rgba(245, 158, 11, 0.12);
    border: 1px solid rgba(245, 158, 11, 0.25);
    border-radius: var(--radius-full);
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--amber-300);
    margin-bottom: var(--space-lg);
    animation: fadeInUp 0.6s var(--ease-out) both;
}
.hero__badge-dot {
    width: 6px;
    height: 6px;
    background: var(--amber-400);
    border-radius: 50%;
    position: relative;
}
.hero__badge-dot::after {
    content: '';
    position: absolute;
    inset: -3px;
    border-radius: 50%;
    border: 1px solid var(--amber-400);
    animation: pulse-ring 2s ease-out infinite;
}

.hero h1 {
    font-size: clamp(2rem, 5vw, 3.25rem);
    font-weight: 900;
    color: #fff;
    letter-spacing: -0.03em;
    margin-bottom: var(--space-md);
    animation: fadeInUp 0.6s var(--ease-out) 0.1s both;
}
.hero h1 em {
    font-style: normal;
    color: var(--amber-400);
    position: relative;
}

.hero__subtitle {
    font-size: 1.125rem;
    color: var(--navy-300);
    line-height: 1.7;
    margin-bottom: var(--space-xl);
    animation: fadeInUp 0.6s var(--ease-out) 0.2s both;
}

.hero__stats {
    display: flex;
    justify-content: center;
    gap: var(--space-xl);
    animation: fadeInUp 0.6s var(--ease-out) 0.3s both;
}
.hero__stat {
    text-align: center;
}
.hero__stat-number {
    font-family: var(--font-display);
    font-size: 2rem;
    font-weight: 900;
    color: #fff;
    display: block;
}
.hero__stat-label {
    font-size: 0.8125rem;
    color: var(--navy-400);
    margin-top: 2px;
}

/* ─── Search ─── */
.search-bar {
    max-width: 560px;
    margin: 0 auto var(--space-xl);
    position: relative;
    animation: fadeInUp 0.6s var(--ease-out) 0.25s both;
}
.search-bar__input {
    width: 100%;
    padding: 16px 20px 16px 52px;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: var(--radius-lg);
    color: #fff;
    font-family: var(--font-body);
    font-size: 1rem;
    outline: none;
    transition: all var(--duration-normal) var(--ease-out);
}
.search-bar__input::placeholder { color: var(--navy-400); }
.search-bar__input:focus {
    background: rgba(255, 255, 255, 0.12);
    border-color: var(--amber-500);
    box-shadow: 0 0 0 4px rgba(245, 158, 11, 0.15);
}
.search-bar__icon {
    position: absolute;
    left: 18px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--navy-400);
    font-size: 1.25rem;
}

/* ─── Section ─── */
.section {
    padding: var(--space-2xl) 0;
}
.section__header {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    margin-bottom: var(--space-xl);
}
.section__title {
    font-size: clamp(1.375rem, 3vw, 1.75rem);
    font-weight: 700;
    letter-spacing: -0.02em;
}
.section__title-accent {
    color: var(--amber-500);
}
.section__count {
    font-size: 0.875rem;
    color: var(--navy-400);
    font-weight: 500;
}

/* ─── Calculator Cards Grid ─── */
.calc-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--space-md);
}

.calc-card {
    background: var(--bg-card);
    border: 1px solid var(--navy-100);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
    text-decoration: none;
    transition: all var(--duration-normal) var(--ease-out);
    position: relative;
    overflow: hidden;
    animation: fadeInUp 0.4s var(--ease-out) both;
}
.calc-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--amber-500), var(--amber-300));
    transform: scaleX(0);
    transform-origin: left;
    transition: transform var(--duration-normal) var(--ease-out);
}
.calc-card:hover {
    border-color: var(--amber-200);
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
}
.calc-card:hover::before {
    transform: scaleX(1);
}

.calc-card__icon {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    background: var(--amber-glow);
    border-radius: var(--radius-md);
    flex-shrink: 0;
}

.calc-card__title {
    font-family: var(--font-display);
    font-size: 0.9375rem;
    font-weight: 600;
    color: var(--navy-950);
    line-height: 1.3;
}

.calc-card__desc {
    font-size: 0.8125rem;
    color: var(--navy-500);
    line-height: 1.5;
    flex-grow: 1;
}

.calc-card__tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-xs);
    margin-top: var(--space-xs);
}
.calc-card__tag {
    padding: 2px 10px;
    font-size: 0.6875rem;
    font-weight: 600;
    border-radius: var(--radius-full);
    text-transform: uppercase;
    letter-spacing: 0.03em;
}
.calc-card__tag--t1 {
    background: rgba(16, 185, 129, 0.1);
    color: #059669;
}
.calc-card__tag--t2 {
    background: rgba(59, 130, 246, 0.1);
    color: #2563eb;
}
.calc-card__tag--t3 {
    background: rgba(139, 92, 246, 0.1);
    color: #7c3aed;
}
.calc-card__tag--new {
    background: var(--amber-glow);
    color: var(--amber-500);
}

/* ─── Calculator Page ─── */
.calc-page {
    padding: var(--space-xl) 0 var(--space-3xl);
}
.calc-page__layout {
    display: grid;
    grid-template-columns: 1fr 340px;
    gap: var(--space-xl);
    align-items: start;
}

/* Calculator Widget */
.calc-widget {
    background: var(--bg-card);
    border: 1px solid var(--navy-100);
    border-radius: var(--radius-xl);
    padding: var(--space-xl);
    box-shadow: var(--shadow-md);
    position: relative;
    overflow: hidden;
}
.calc-widget::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--amber-500), var(--amber-300), var(--info));
}

.calc-widget__title {
    font-size: 1.5rem;
    margin-bottom: var(--space-xs);
}
.calc-widget__subtitle {
    font-size: 0.9375rem;
    color: var(--navy-500);
    margin-bottom: var(--space-xl);
}

/* Form elements */
.form-group {
    margin-bottom: var(--space-md);
}
.form-label {
    display: block;
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--navy-700);
    margin-bottom: var(--space-xs);
    letter-spacing: 0.01em;
}
.form-hint {
    font-size: 0.75rem;
    color: var(--navy-400);
    margin-top: 2px;
}
.form-input,
.form-select {
    width: 100%;
    padding: 12px 16px;
    background: var(--bg-input);
    border: 2px solid transparent;
    border-radius: var(--radius-md);
    font-family: var(--font-body);
    font-size: 1rem;
    font-weight: 500;
    color: var(--navy-950);
    outline: none;
    transition: all var(--duration-fast) var(--ease-out);
}
.form-input:focus,
.form-select:focus {
    border-color: var(--amber-500);
    background: #fff;
    box-shadow: 0 0 0 4px var(--amber-glow);
}
.form-input::placeholder { color: var(--navy-300); }

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-md);
}

.form-toggle {
    display: flex;
    background: var(--bg-input);
    border-radius: var(--radius-md);
    padding: 3px;
    gap: 3px;
}
.form-toggle__btn {
    flex: 1;
    padding: 10px;
    border: none;
    background: transparent;
    font-family: var(--font-body);
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--navy-500);
    border-radius: calc(var(--radius-md) - 2px);
    cursor: pointer;
    transition: all var(--duration-fast) var(--ease-out);
}
.form-toggle__btn--active {
    background: #fff;
    color: var(--navy-950);
    box-shadow: var(--shadow-sm);
}

.btn-calc {
    width: 100%;
    padding: 14px;
    background: linear-gradient(135deg, var(--amber-500), var(--amber-400));
    border: none;
    border-radius: var(--radius-md);
    font-family: var(--font-display);
    font-size: 0.9375rem;
    font-weight: 700;
    color: var(--navy-950);
    cursor: pointer;
    transition: all var(--duration-fast) var(--ease-out);
    margin-top: var(--space-lg);
    letter-spacing: -0.01em;
}
.btn-calc:hover {
    box-shadow: var(--shadow-glow);
    transform: translateY(-2px);
}
.btn-calc:active {
    transform: translateY(0);
}

/* Result Block */
.result-block {
    margin-top: var(--space-xl);
    padding: var(--space-lg);
    background: linear-gradient(135deg, var(--navy-950), var(--navy-800));
    border-radius: var(--radius-lg);
    display: none;
}
.result-block--visible {
    display: block;
    animation: fadeInUp 0.4s var(--ease-out);
}
.result-block__label {
    font-size: 0.8125rem;
    color: var(--navy-300);
    font-weight: 500;
    margin-bottom: var(--space-xs);
}
.result-block__value {
    font-family: var(--font-display);
    font-size: clamp(1.5rem, 4vw, 2.25rem);
    font-weight: 900;
    color: var(--amber-400);
    letter-spacing: -0.02em;
}
.result-block__detail {
    font-size: 0.875rem;
    color: var(--navy-200);
    margin-top: var(--space-md);
    line-height: 1.7;
}

.result-table {
    width: 100%;
    margin-top: var(--space-md);
    border-collapse: separate;
    border-spacing: 0;
}
.result-table th,
.result-table td {
    padding: 10px 14px;
    font-size: 0.875rem;
    text-align: left;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}
.result-table th {
    color: var(--navy-400);
    font-weight: 500;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}
.result-table td {
    color: var(--navy-100);
    font-weight: 500;
}
.result-table td:last-child {
    text-align: right;
    font-family: var(--font-display);
    font-weight: 700;
    color: #fff;
}

/* Sidebar */
.sidebar {
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
    position: sticky;
    top: 84px;
}

.sidebar-card {
    background: var(--bg-card);
    border: 1px solid var(--navy-100);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
}
.sidebar-card__title {
    font-family: var(--font-display);
    font-size: 0.875rem;
    font-weight: 700;
    margin-bottom: var(--space-md);
}

.related-link {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: 10px 0;
    border-bottom: 1px solid var(--navy-50);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--navy-700);
}
.related-link:last-child { border-bottom: none; }
.related-link:hover { color: var(--amber-500); }
.related-link__icon { font-size: 1.1rem; }

/* CPA Banner */
.cpa-banner {
    background: linear-gradient(135deg, #e8f5e9, #f1f8e9);
    border: 1px solid #c8e6c9;
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    text-align: center;
}
.cpa-banner__title {
    font-family: var(--font-display);
    font-size: 0.875rem;
    font-weight: 700;
    color: var(--navy-900);
    margin-bottom: var(--space-sm);
}
.cpa-banner__text {
    font-size: 0.8125rem;
    color: var(--navy-600);
    margin-bottom: var(--space-md);
}
.cpa-banner__btn {
    display: inline-block;
    padding: 10px 24px;
    background: #2e7d32;
    color: #fff;
    font-weight: 600;
    font-size: 0.875rem;
    border-radius: var(--radius-full);
    transition: background var(--duration-fast);
}
.cpa-banner__btn:hover {
    background: #1b5e20;
    color: #fff;
}

/* ─── Content / SEO Article ─── */
.article {
    margin-top: var(--space-2xl);
    max-width: 760px;
}
.article h2 {
    font-size: 1.375rem;
    margin: var(--space-xl) 0 var(--space-md);
}
.article h3 {
    font-size: 1.125rem;
    margin: var(--space-lg) 0 var(--space-sm);
}
.article p {
    margin-bottom: var(--space-md);
    color: var(--navy-700);
}
.article ul, .article ol {
    margin: var(--space-md) 0;
    padding-left: var(--space-lg);
}
.article li {
    margin-bottom: var(--space-sm);
    color: var(--navy-700);
}
.article table {
    width: 100%;
    border-collapse: collapse;
    margin: var(--space-lg) 0;
}
.article th, .article td {
    padding: 12px 16px;
    border: 1px solid var(--navy-100);
    font-size: 0.9375rem;
}
.article th {
    background: var(--navy-50);
    font-weight: 600;
    text-align: left;
}

/* ─── FAQ Block ─── */
.faq {
    margin-top: var(--space-2xl);
    max-width: 760px;
}
.faq__title {
    font-size: 1.375rem;
    margin-bottom: var(--space-lg);
}
.faq-item {
    border: 1px solid var(--navy-100);
    border-radius: var(--radius-md);
    margin-bottom: var(--space-sm);
    overflow: hidden;
    transition: border-color var(--duration-fast);
}
.faq-item:hover { border-color: var(--navy-200); }
.faq-item__question {
    width: 100%;
    padding: 16px 20px;
    background: none;
    border: none;
    font-family: var(--font-body);
    font-size: 0.9375rem;
    font-weight: 600;
    color: var(--navy-900);
    text-align: left;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.faq-item__question::after {
    content: '+';
    font-size: 1.25rem;
    color: var(--navy-400);
    transition: transform var(--duration-normal) var(--ease-out);
}
.faq-item--open .faq-item__question::after {
    transform: rotate(45deg);
    color: var(--amber-500);
}
.faq-item__answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--duration-slow) var(--ease-out);
}
.faq-item--open .faq-item__answer {
    max-height: 500px;
}
.faq-item__answer-inner {
    padding: 0 20px 16px;
    font-size: 0.9375rem;
    color: var(--navy-600);
    line-height: 1.7;
}

/* ─── Breadcrumbs ─── */
.breadcrumbs {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-md) 0;
    font-size: 0.8125rem;
    color: var(--navy-400);
}
.breadcrumbs a { color: var(--navy-500); font-weight: 500; }
.breadcrumbs a:hover { color: var(--amber-500); }
.breadcrumbs__sep { color: var(--navy-200); }

/* ─── Ad Slots ─── */
.ad-slot {
    min-height: 0;
    text-align: center;
}
.ad-slot--sidebar {
    background: var(--navy-50);
    border-radius: var(--radius-md);
    padding: var(--space-lg);
    min-height: 250px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--navy-300);
    font-size: 0.75rem;
}
.ad-slot--inline {
    margin: var(--space-xl) 0;
    padding: var(--space-md);
    background: var(--navy-50);
    border-radius: var(--radius-md);
}

/* ─── Footer ─── */
.footer {
    background: var(--navy-950);
    padding: var(--space-2xl) 0 var(--space-xl);
    margin-top: var(--space-3xl);
}
.footer__grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: var(--space-xl);
}
.footer__desc {
    font-size: 0.875rem;
    color: var(--navy-400);
    margin-top: var(--space-md);
    line-height: 1.7;
}
.footer__heading {
    font-family: var(--font-display);
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--navy-300);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: var(--space-md);
}
.footer__col {
    display: flex;
    flex-direction: column;
}
.footer__link {
    font-size: 0.875rem;
    color: var(--navy-400);
    padding: 4px 0;
    transition: color var(--duration-fast);
}
.footer__link:hover { color: var(--amber-400); }
.footer__bottom {
    margin-top: var(--space-xl);
    padding-top: var(--space-lg);
    border-top: 1px solid rgba(255, 255, 255, 0.06);
    font-size: 0.8125rem;
    color: var(--navy-500);
}

/* ─── Responsive ─── */
@media (max-width: 1024px) {
    .calc-page__layout {
        grid-template-columns: 1fr;
    }
    .sidebar {
        position: static;
    }
}

@media (max-width: 768px) {
    .nav { display: none; }
    .nav--open {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 68px;
        left: 0;
        right: 0;
        background: #fff;
        padding: var(--space-lg);
        box-shadow: var(--shadow-lg);
        border-bottom: 1px solid var(--navy-100);
        animation: slideDown 0.3s var(--ease-out);
    }
    .burger { display: flex; }

    .hero { padding: var(--space-2xl) 0 var(--space-xl); }
    .hero h1 { font-size: 1.75rem; }
    .hero__stats { gap: var(--space-lg); }
    .hero__stat-number { font-size: 1.5rem; }

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

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

    .footer__grid {
        grid-template-columns: 1fr 1fr;
        gap: var(--space-lg);
    }
}

@media (max-width: 480px) {
    .container { padding: 0 var(--space-md); }
    .hero__stats { flex-direction: column; gap: var(--space-md); }
    .footer__grid { grid-template-columns: 1fr; }
}

/* ─── Utility classes ─── */
.text-amber { color: var(--amber-500); }
.text-navy { color: var(--navy-950); }
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mt-xl { margin-top: var(--space-xl); }
.hidden { display: none !important; }
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}

/* ─── Staggered card animations ─── */
.calc-grid .calc-card:nth-child(1) { animation-delay: 0.03s; }
.calc-grid .calc-card:nth-child(2) { animation-delay: 0.06s; }
.calc-grid .calc-card:nth-child(3) { animation-delay: 0.09s; }
.calc-grid .calc-card:nth-child(4) { animation-delay: 0.12s; }
.calc-grid .calc-card:nth-child(5) { animation-delay: 0.15s; }
.calc-grid .calc-card:nth-child(6) { animation-delay: 0.18s; }
.calc-grid .calc-card:nth-child(7) { animation-delay: 0.21s; }
.calc-grid .calc-card:nth-child(8) { animation-delay: 0.24s; }

/* ─── FileTools Banner ─── */
.ft-banner {
    display: flex;
    align-items: center;
    gap: var(--space-lg);
    padding: 20px 28px;
    background: linear-gradient(135deg, #312e81, #4338ca, #4f46e5);
    border: none;
    border-radius: var(--radius-lg);
    text-decoration: none;
    transition: all var(--duration-normal) var(--ease-out);
    box-shadow: 0 4px 20px rgba(79, 70, 229, 0.3);
}
.ft-banner:hover {
    box-shadow: 0 8px 32px rgba(79, 70, 229, 0.45);
    transform: translateY(-3px);
}
.ft-banner__icon {
    font-size: 2.25rem;
    flex-shrink: 0;
}
.ft-banner__text {
    flex-grow: 1;
    font-size: 0.9375rem;
    color: rgba(255,255,255,0.85);
    line-height: 1.5;
}
.ft-banner__text strong {
    color: #fff;
    font-size: 1.0625rem;
    display: block;
    margin-bottom: 2px;
}
.ft-banner__btn {
    flex-shrink: 0;
    padding: 10px 24px;
    background: #fff;
    color: #4338ca;
    font-size: 0.875rem;
    font-weight: 700;
    border-radius: var(--radius-full);
    white-space: nowrap;
    transition: all var(--duration-fast);
}
.ft-banner:hover .ft-banner__btn {
    background: var(--amber-400);
    color: var(--navy-950);
}
@media (max-width: 768px) {
    .ft-banner { flex-direction: column; text-align: center; }
}