:root {
  --bk-blue-dark: #041b4d;
  --bk-blue-deep: #062b6f;
  --bk-blue-main: #0b63ce;
  --bk-blue-mid: #1685f8;
  --bk-blue-light: #40b7ff;
  --bk-blue-soft: #eaf5ff;
  --bk-blue-glass: rgba(64, 183, 255, .16);
  --bk-white: #ffffff;
  --bk-black: #080b12;
  --bk-text: #172033;
  --bk-muted: #65738a;
  --bk-border: rgba(64, 183, 255, .28);
  --bk-border-soft: #d7e9ff;
  --bk-danger: #ff4d6d;
  --bk-success: #19c37d;
  --bk-radius-sm: 10px;
  --bk-radius-md: 16px;
  --bk-radius-lg: 24px;
  --bk-shadow-soft: 0 12px 32px rgba(4, 27, 77, .12);
  --bk-shadow-strong: 0 20px 55px rgba(4, 27, 77, .24);
  --bk-gradient-main: linear-gradient(135deg, #041b4d 0%, #0b63ce 48%, #40b7ff 100%);
  --bk-gradient-dark: linear-gradient(135deg, #020817 0%, #041b4d 50%, #062b6f 100%);
  --bk-gradient-soft: linear-gradient(135deg, #f7fbff 0%, #eaf5ff 48%, #ffffff 100%);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  background:
    radial-gradient(circle at 8% 8%, rgba(64, 183, 255, .18), transparent 28%),
    radial-gradient(circle at 92% 22%, rgba(11, 99, 206, .16), transparent 30%),
    linear-gradient(180deg, #f7fbff 0%, #eef7ff 48%, #ffffff 100%);
  color: var(--bk-text);
  overflow-x: hidden;
}

body::before,
body::after {
  content: "";
  position: fixed;
  width: 380px;
  height: 380px;
  border-radius: 999px;
  pointer-events: none;
  z-index: -1;
  filter: blur(10px);
  opacity: .5;
  animation: bkFloatGlow 12s ease-in-out infinite;
}

body::before {
  left: -160px;
  top: 160px;
  background: radial-gradient(circle, rgba(64, 183, 255, .26), transparent 68%);
}

body::after {
  right: -160px;
  bottom: 80px;
  background: radial-gradient(circle, rgba(11, 99, 206, .22), transparent 68%);
  animation-delay: -5s;
}

a {
  color: inherit;
}

img {
  max-width: 100%;
  height: auto;
}

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

.bk-container {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
}

.bk-light-sweep {
  position: relative;
  overflow: hidden;
}

.bk-light-sweep::after {
  content: "";
  position: absolute;
  top: -40%;
  left: -80%;
  width: 54%;
  height: 180%;
  background: linear-gradient(
    115deg,
    transparent 0%,
    rgba(255,255,255,0) 20%,
    rgba(255,255,255,.38) 48%,
    rgba(255,255,255,0) 78%,
    transparent 100%
  );
  transform: rotate(10deg);
  animation: bkLightSweep 4.8s ease-in-out infinite;
  pointer-events: none;
}

.bk-topbar {
  background: var(--bk-gradient-dark);
  color: var(--bk-white);
  font-size: 14px;
  position: relative;
  overflow: hidden;
}

.bk-topbar::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, transparent, rgba(64,183,255,.18), transparent);
  animation: bkTopbarFlow 6s linear infinite;
  pointer-events: none;
}

.bk-topbar-inner {
  min-height: 39px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  position: relative;
  z-index: 1;
}

.bk-topbar-left {
  font-weight: 800;
  letter-spacing: .2px;
}

.bk-topbar-right {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}

.bk-topbar-right a {
  text-decoration: none;
  color: var(--bk-white);
  font-weight: 800;
  opacity: .94;
}

.bk-topbar-right a:hover {
  opacity: 1;
  text-shadow: 0 0 12px rgba(64,183,255,.8);
}

.bk-navbar {
  background: rgba(255,255,255,.92);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--bk-border-soft);
  box-shadow: 0 8px 28px rgba(4,27,77,.08);
  position: sticky;
  top: 0;
  z-index: 90;
}

.bk-nav-inner {
  min-height: 78px;
  display: grid;
  grid-template-columns: 230px 1fr auto;
  align-items: center;
  gap: 18px;
}

.bk-logo {
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 27px;
  line-height: 1;
  font-weight: 950;
  color: var(--bk-blue-dark);
  letter-spacing: .4px;
}

.bk-logo-mark {
  width: 42px;
  height: 42px;
  border-radius: 13px;
  display: inline-grid;
  place-items: center;
  color: var(--bk-white);
  background: var(--bk-gradient-main);
  box-shadow: 0 12px 28px rgba(11,99,206,.28);
  position: relative;
  overflow: hidden;
}

.bk-logo-mark::after {
  content: "";
  position: absolute;
  inset: -50%;
  background: linear-gradient(115deg, transparent 30%, rgba(255,255,255,.46), transparent 65%);
  animation: bkMiniSweep 3.7s ease-in-out infinite;
}

.bk-logo-text span {
  color: var(--bk-blue-mid);
}

.bk-search {
  display: flex;
  align-items: center;
  border: 1px solid var(--bk-border-soft);
  border-radius: 999px;
  background: var(--bk-blue-soft);
  overflow: hidden;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.7);
}

.bk-search input {
  width: 100%;
  border: 0;
  outline: 0;
  background: transparent;
  padding: 14px 17px;
  color: var(--bk-text);
}

.bk-search button {
  border: 0;
  min-width: 62px;
  padding: 14px 18px;
  background: var(--bk-blue-main);
  color: var(--bk-white);
  font-weight: 900;
  cursor: pointer;
  transition: transform .22s ease, background .22s ease;
}

.bk-search button:hover {
  background: var(--bk-blue-dark);
}

.bk-nav-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.bk-icon-btn,
.bk-nav-btn,
.bk-cta,
.bk-fixed-cta a,
.bk-product-btn,
.bk-calc-btn {
  position: relative;
  overflow: hidden;
}

.bk-icon-btn::after,
.bk-nav-btn::after,
.bk-cta::after,
.bk-fixed-cta a::after,
.bk-product-btn::after,
.bk-calc-btn::after {
  content: "";
  position: absolute;
  top: -50%;
  left: -80%;
  width: 42%;
  height: 200%;
  transform: rotate(18deg);
  background: linear-gradient(90deg, transparent, rgba(255,255,255,.38), transparent);
  transition: left .6s ease;
  pointer-events: none;
}

.bk-icon-btn:hover::after,
.bk-nav-btn:hover::after,
.bk-cta:hover::after,
.bk-fixed-cta a:hover::after,
.bk-product-btn:hover::after,
.bk-calc-btn:hover::after {
  left: 130%;
}

.bk-nav-btn {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  min-height: 42px;
  padding: 10px 16px;
  border-radius: 999px;
  background: var(--bk-blue-main);
  color: var(--bk-white);
  text-decoration: none;
  font-weight: 900;
  box-shadow: 0 12px 24px rgba(11,99,206,.18);
}

.bk-nav-btn.bk-dark {
  background: var(--bk-blue-dark);
}

.bk-icon-btn {
  width: 42px;
  height: 42px;
  border: 1px solid var(--bk-border-soft);
  border-radius: 999px;
  background: var(--bk-white);
  color: var(--bk-blue-dark);
  display: inline-grid;
  place-items: center;
  cursor: pointer;
  box-shadow: 0 8px 18px rgba(4,27,77,.08);
}

.bk-mega {
  border-top: 1px solid var(--bk-border-soft);
  background: rgba(255,255,255,.72);
}

.bk-mega-scroll {
  display: flex;
  gap: 10px;
  overflow-x: auto;
  padding: 12px 0;
  scrollbar-width: none;
}

.bk-mega-scroll::-webkit-scrollbar {
  display: none;
}

.bk-mega-scroll a {
  flex: 0 0 auto;
  text-decoration: none;
  padding: 10px 15px;
  border-radius: 999px;
  background: linear-gradient(180deg, #ffffff 0%, var(--bk-blue-soft) 100%);
  border: 1px solid var(--bk-border-soft);
  color: var(--bk-blue-dark);
  font-size: 14px;
  font-weight: 900;
  box-shadow: 0 8px 18px rgba(4,27,77,.06);
  transition: transform .22s ease, box-shadow .22s ease, border-color .22s ease;
}

.bk-mega-scroll a:hover {
  transform: translateY(-2px);
  border-color: rgba(64,183,255,.6);
  box-shadow: 0 12px 28px rgba(11,99,206,.16);
}

.bk-hero {
  padding: 30px 0 18px;
}

.bk-product-shell {
  background:
    radial-gradient(circle at 84% 8%, rgba(64,183,255,.26), transparent 28%),
    linear-gradient(135deg, rgba(255,255,255,.96), rgba(234,245,255,.96));
  border: 1px solid var(--bk-border-soft);
  border-radius: 28px;
  box-shadow: var(--bk-shadow-strong);
  padding: 24px;
  position: relative;
  overflow: hidden;
}

.bk-product-shell::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  padding: 1px;
  background: linear-gradient(135deg, rgba(64,183,255,.86), transparent 38%, rgba(11,99,206,.45));
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  pointer-events: none;
}

.bk-product-layout {
  display: grid;
  grid-template-columns: .9fr 1.1fr;
  gap: 26px;
  align-items: start;
  position: relative;
  z-index: 1;
}

.bk-product-media {
  background: var(--bk-gradient-dark);
  border-radius: 24px;
  padding: 18px;
  min-height: 360px;
  display: grid;
  place-items: center;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.12);
  position: relative;
  overflow: hidden;
}

.bk-product-media::before {
  content: "";
  position: absolute;
  width: 260px;
  height: 260px;
  border-radius: 999px;
  background: radial-gradient(circle, rgba(64,183,255,.34), transparent 66%);
  animation: bkGlowPulse 4s ease-in-out infinite;
}

.bk-product-img {
  width: min(100%, 520px);
  border-radius: 20px;
  position: relative;
  z-index: 2;
  box-shadow: 0 22px 48px rgba(0,0,0,.28);
}

.bk-product-placeholder {
  position: relative;
  z-index: 2;
  min-height: 260px;
  width: 100%;
  border-radius: 20px;
  border: 1px dashed rgba(255,255,255,.34);
  display: grid;
  place-items: center;
  text-align: center;
  color: var(--bk-white);
  padding: 28px;
  background:
    radial-gradient(circle at 50% 0%, rgba(64,183,255,.22), transparent 48%),
    rgba(255,255,255,.06);
}

.bk-badge {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  border-radius: 999px;
  padding: 8px 13px;
  color: var(--bk-white);
  background: var(--bk-gradient-main);
  font-size: 13px;
  font-weight: 950;
  box-shadow: 0 12px 24px rgba(11,99,206,.2);
}

.bk-product-title {
  margin: 14px 0 10px;
  font-size: clamp(30px, 4vw, 52px);
  line-height: 1.06;
  color: var(--bk-blue-dark);
  letter-spacing: -.8px;
}

.bk-product-subtitle {
  margin: 0 0 18px;
  color: var(--bk-muted);
  font-size: 17px;
  line-height: 1.75;
}

.bk-rating-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 16px 0;
}

.bk-rating-pill {
  padding: 9px 13px;
  border-radius: 999px;
  border: 1px solid var(--bk-border-soft);
  background: var(--bk-white);
  color: var(--bk-blue-dark);
  font-weight: 900;
  box-shadow: 0 8px 18px rgba(4,27,77,.06);
}

.bk-price-card {
  margin: 18px 0;
  background: var(--bk-blue-soft);
  border: 1px solid var(--bk-border-soft);
  border-radius: 20px;
  padding: 17px;
  display: grid;
  gap: 8px;
}

.bk-price-label {
  color: var(--bk-muted);
  font-size: 13px;
  font-weight: 800;
}

.bk-price-value {
  color: var(--bk-blue-dark);
  font-size: 34px;
  font-weight: 950;
}

.bk-cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 18px 0 0;
}

.bk-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 13px 22px;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 950;
  background: var(--bk-blue-main);
  color: var(--bk-white);
  box-shadow: 0 15px 28px rgba(11,99,206,.22);
  transition: transform .22s ease, box-shadow .22s ease;
}

.bk-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 20px 36px rgba(11,99,206,.28);
}

.bk-cta.bk-ghost {
  background: var(--bk-white);
  color: var(--bk-blue-dark);
  border: 1px solid var(--bk-border-soft);
}

.bk-trust-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 11px;
  margin-top: 18px;
}

.bk-trust-item {
  border-radius: 16px;
  background: var(--bk-white);
  border: 1px solid var(--bk-border-soft);
  padding: 13px;
  box-shadow: 0 8px 18px rgba(4,27,77,.06);
}

.bk-trust-item strong {
  display: block;
  color: var(--bk-blue-dark);
  margin-bottom: 4px;
}

.bk-trust-item span {
  color: var(--bk-muted);
  font-size: 13px;
  line-height: 1.45;
}

.bk-section {
  padding: 22px 0;
}

.bk-section-title {
  text-align: center;
  margin: 0 0 18px;
  color: var(--bk-blue-dark);
  font-size: clamp(26px, 3vw, 38px);
  line-height: 1.15;
}

.bk-section-desc {
  width: min(760px, 100%);
  margin: -6px auto 22px;
  color: var(--bk-muted);
  text-align: center;
  line-height: 1.75;
}

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

.bk-info-card {
  position: relative;
  overflow: hidden;
  border-radius: 22px;
  padding: 20px;
  background: var(--bk-white);
  border: 1px solid var(--bk-border-soft);
  box-shadow: var(--bk-shadow-soft);
  transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
}

.bk-info-card:hover {
  transform: translateY(-5px);
  border-color: rgba(64,183,255,.58);
  box-shadow: var(--bk-shadow-strong);
}

.bk-info-card h3 {
  margin: 0 0 10px;
  color: var(--bk-blue-dark);
  font-size: 20px;
}

.bk-info-card p {
  margin: 0;
  color: var(--bk-muted);
  line-height: 1.7;
}

.bk-progress {
  height: 10px;
  border-radius: 999px;
  background: #dbeeff;
  overflow: hidden;
  margin-top: 16px;
}

.bk-progress span {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: var(--bk-gradient-main);
  animation: bkProgressFill 3s ease-in-out infinite alternate;
}

.bk-calc-box {
  background:
    radial-gradient(circle at top right, rgba(64,183,255,.22), transparent 34%),
    var(--bk-white);
  border: 1px solid var(--bk-border-soft);
  border-radius: 26px;
  box-shadow: var(--bk-shadow-strong);
  padding: 22px;
  overflow: hidden;
  position: relative;
}

.bk-calc-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 16px;
}

.bk-calc-head h2 {
  margin: 0;
  color: var(--bk-blue-dark);
}

.bk-calc-head p {
  margin: 6px 0 0;
  color: var(--bk-muted);
  line-height: 1.6;
}

.bk-calc-form {
  display: grid;
  grid-template-columns: 1.3fr .7fr .55fr auto;
  gap: 10px;
  margin-bottom: 14px;
}

.bk-calc-form input {
  width: 100%;
  border: 1px solid var(--bk-border-soft);
  border-radius: 13px;
  padding: 12px 13px;
  outline: 0;
  background: #fbfdff;
}

.bk-calc-form input:focus {
  border-color: var(--bk-blue-light);
  box-shadow: 0 0 0 4px rgba(64,183,255,.15);
}

.bk-calc-btn {
  border: 0;
  border-radius: 13px;
  padding: 12px 16px;
  background: var(--bk-blue-main);
  color: var(--bk-white);
  font-weight: 950;
  cursor: pointer;
}

.bk-cart-list {
  display: grid;
  gap: 10px;
}

.bk-cart-item {
  display: grid;
  grid-template-columns: 1fr auto auto auto;
  gap: 10px;
  align-items: center;
  border: 1px solid var(--bk-border-soft);
  border-radius: 16px;
  padding: 12px;
  background: #fbfdff;
}

.bk-cart-item strong {
  color: var(--bk-blue-dark);
}

.bk-cart-item span {
  color: var(--bk-muted);
  font-weight: 800;
}

.bk-cart-remove {
  border: 0;
  border-radius: 10px;
  background: #eaf5ff;
  color: var(--bk-blue-dark);
  font-weight: 950;
  cursor: pointer;
  padding: 9px 11px;
}

.bk-cart-summary {
  margin-top: 16px;
  border-radius: 18px;
  padding: 17px;
  background: var(--bk-gradient-dark);
  color: var(--bk-white);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
}

.bk-cart-summary small {
  display: block;
  opacity: .78;
  margin-bottom: 4px;
}

.bk-cart-total {
  font-size: 28px;
  font-weight: 950;
}

.bk-article-glow {
  position: relative;
  margin: 22px 0;
  padding: 30px;
  border-radius: 28px;
  background:
    linear-gradient(180deg, rgba(255,255,255,.96), rgba(234,245,255,.96)),
    radial-gradient(circle at 10% 0%, rgba(64,183,255,.18), transparent 40%);
  border: 1px solid var(--bk-border-soft);
  box-shadow: var(--bk-shadow-strong);
  overflow: hidden;
}

.bk-article-glow::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at 0% 0%, rgba(64,183,255,.25), transparent 30%),
    radial-gradient(circle at 100% 10%, rgba(11,99,206,.18), transparent 30%);
  opacity: .9;
}

.bk-article-shine {
  position: absolute;
  inset: -30% auto auto -60%;
  width: 50%;
  height: 160%;
  transform: rotate(18deg);
  background: linear-gradient(90deg, transparent, rgba(255,255,255,.7), transparent);
  animation: bkArticleShine 5.8s ease-in-out infinite;
  pointer-events: none;
}

.bk-article-content {
  position: relative;
  z-index: 1;
}

.bk-article-content h2,
.bk-article-content h3 {
  color: var(--bk-blue-dark);
  line-height: 1.25;
}

.bk-article-content h2 {
  font-size: clamp(26px, 3vw, 38px);
  margin: 0 0 14px;
}

.bk-article-content h3 {
  font-size: 23px;
  margin: 28px 0 10px;
}

.bk-article-content p {
  color: #263348;
  line-height: 1.85;
  font-size: 16px;
}

.bk-article-content a {
  color: var(--bk-blue-main);
  font-weight: 900;
  text-decoration: none;
}

.bk-note-box {
  border-radius: 18px;
  border: 1px solid rgba(64,183,255,.36);
  background: rgba(234,245,255,.78);
  padding: 18px;
  margin: 18px 0;
  color: #263348;
  line-height: 1.75;
}

.bk-faq-wrap {
  background:
    radial-gradient(circle at 82% 0%, rgba(64,183,255,.24), transparent 34%),
    var(--bk-white);
  border: 1px solid var(--bk-border-soft);
  border-radius: 28px;
  box-shadow: var(--bk-shadow-strong);
  padding: 28px;
  overflow: hidden;
  position: relative;
}

.bk-faq-head {
  text-align: center;
  margin-bottom: 18px;
}

.bk-faq-head .bk-badge {
  margin-bottom: 10px;
}

.bk-faq-head h2 {
  margin: 0;
  color: var(--bk-blue-dark);
  font-size: clamp(26px, 3vw, 38px);
}

.bk-faq-item {
  border: 1px solid var(--bk-border-soft);
  border-radius: 18px;
  background: #fbfdff;
  margin: 12px 0;
  overflow: hidden;
  transition: border-color .22s ease, box-shadow .22s ease;
}

.bk-faq-item[open] {
  border-color: rgba(64,183,255,.65);
  box-shadow: 0 12px 24px rgba(11,99,206,.12);
}

.bk-faq-item summary {
  list-style: none;
  cursor: pointer;
  padding: 17px 18px;
  color: var(--bk-blue-dark);
  font-weight: 950;
  display: flex;
  justify-content: space-between;
  gap: 14px;
}

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

.bk-faq-item summary::after {
  content: "+";
  width: 26px;
  height: 26px;
  border-radius: 999px;
  background: var(--bk-blue-soft);
  display: inline-grid;
  place-items: center;
  color: var(--bk-blue-main);
  transition: transform .22s ease, background .22s ease;
}

.bk-faq-item[open] summary::after {
  content: "−";
  transform: rotate(180deg);
  background: var(--bk-blue-main);
  color: var(--bk-white);
}

.bk-faq-item p {
  margin: 0;
  padding: 0 18px 18px;
  color: var(--bk-muted);
  line-height: 1.8;
}

.bk-related-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.bk-product-card {
  background: var(--bk-white);
  border: 1px solid var(--bk-border-soft);
  border-radius: 22px;
  overflow: hidden;
  box-shadow: var(--bk-shadow-soft);
  transition: transform .22s ease, box-shadow .22s ease, border-color .22s ease;
}

.bk-product-card:hover {
  transform: translateY(-5px);
  border-color: rgba(64,183,255,.62);
  box-shadow: var(--bk-shadow-strong);
}

.bk-product-card-media {
  min-height: 150px;
  background: var(--bk-gradient-dark);
  display: grid;
  place-items: center;
  color: var(--bk-white);
  text-align: center;
  padding: 18px;
  position: relative;
  overflow: hidden;
}

.bk-product-card-body {
  padding: 16px;
}

.bk-product-card h3 {
  margin: 0 0 8px;
  color: var(--bk-blue-dark);
  font-size: 17px;
}

.bk-product-card p {
  margin: 0 0 14px;
  color: var(--bk-muted);
  line-height: 1.55;
  font-size: 14px;
}

.bk-product-btn {
  display: inline-flex;
  justify-content: center;
  width: 100%;
  text-decoration: none;
  border-radius: 12px;
  background: var(--bk-blue-main);
  color: var(--bk-white);
  font-weight: 950;
  padding: 12px;
}

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

.bk-testimonial {
  background: var(--bk-white);
  border: 1px solid var(--bk-border-soft);
  border-radius: 22px;
  padding: 20px;
  box-shadow: var(--bk-shadow-soft);
}

.bk-testimonial p {
  margin: 0 0 16px;
  color: #263348;
  line-height: 1.75;
}

.bk-testimonial strong {
  color: var(--bk-blue-dark);
}

.bk-testimonial small {
  display: block;
  color: var(--bk-muted);
  margin-top: 4px;
}

.bk-footer {
  margin-top: 28px;
  padding: 34px 0 112px;
  background: var(--bk-gradient-dark);
  color: var(--bk-white);
  position: relative;
  overflow: hidden;
}

.bk-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 12% 0%, rgba(64,183,255,.22), transparent 32%),
    radial-gradient(circle at 88% 30%, rgba(11,99,206,.24), transparent 34%);
  pointer-events: none;
}

.bk-footer-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.3fr 1fr 1fr 1fr;
  gap: 24px;
}

.bk-footer h3 {
  margin: 0 0 14px;
  color: var(--bk-white);
}

.bk-footer p {
  margin: 0;
  color: rgba(255,255,255,.76);
  line-height: 1.75;
}

.bk-footer a {
  display: block;
  text-decoration: none;
  color: rgba(255,255,255,.86);
  margin: 10px 0;
  font-weight: 800;
}

.bk-footer a:hover {
  color: var(--bk-white);
  text-shadow: 0 0 12px rgba(64,183,255,.8);
}

.bk-copyright {
  position: relative;
  z-index: 1;
  margin-top: 26px;
  padding-top: 18px;
  border-top: 1px solid rgba(255,255,255,.12);
  color: rgba(255,255,255,.68);
  font-size: 14px;
}

.bk-bottom-nav {
  display: none;
}

.bk-fixed-cta {
  position: fixed;
  left: 50%;
  bottom: 18px;
  transform: translateX(-50%);
  z-index: 120;
  width: min(760px, calc(100% - 28px));
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  padding: 10px;
  border-radius: 20px;
  background: rgba(4, 27, 77, .92);
  backdrop-filter: blur(14px);
  box-shadow: 0 20px 55px rgba(0,0,0,.32);
  border: 1px solid rgba(255,255,255,.14);
}

.bk-fixed-cta a {
  text-decoration: none;
  color: var(--bk-white);
  background: var(--bk-blue-main);
  border-radius: 14px;
  padding: 14px 12px;
  text-align: center;
  font-weight: 950;
}

.bk-fixed-cta a:first-child {
  background: linear-gradient(135deg, var(--bk-blue-light), var(--bk-blue-main));
}

.bk-modal {
  position: fixed;
  inset: 0;
  background: rgba(2, 8, 23, .72);
  backdrop-filter: blur(12px);
  z-index: 200;
  display: none;
  place-items: center;
  padding: 20px;
}

.bk-modal.is-active {
  display: grid;
}

.bk-modal-card {
  width: min(520px, 100%);
  background: var(--bk-white);
  border-radius: 26px;
  padding: 24px;
  border: 1px solid var(--bk-border-soft);
  box-shadow: var(--bk-shadow-strong);
  position: relative;
  overflow: hidden;
}

.bk-modal-card h2 {
  margin: 0 0 10px;
  color: var(--bk-blue-dark);
}

.bk-modal-card p {
  color: var(--bk-muted);
  line-height: 1.75;
}

.bk-modal-close {
  position: absolute;
  top: 14px;
  right: 14px;
  border: 0;
  width: 36px;
  height: 36px;
  border-radius: 999px;
  background: var(--bk-blue-soft);
  color: var(--bk-blue-dark);
  font-weight: 950;
  cursor: pointer;
}

@keyframes bkLightSweep {
  0% { left: -80%; opacity: 0; }
  16% { opacity: .85; }
  46% { left: 138%; opacity: .72; }
  100% { left: 138%; opacity: 0; }
}

@keyframes bkMiniSweep {
  0% { transform: translateX(-80%) rotate(16deg); opacity: 0; }
  28% { opacity: .8; }
  55% { transform: translateX(110%) rotate(16deg); opacity: .45; }
  100% { transform: translateX(110%) rotate(16deg); opacity: 0; }
}

@keyframes bkTopbarFlow {
  0% { transform: translateX(-80%); }
  100% { transform: translateX(80%); }
}

@keyframes bkFloatGlow {
  0%, 100% { transform: translate3d(0,0,0) scale(1); }
  50% { transform: translate3d(22px,-28px,0) scale(1.08); }
}

@keyframes bkGlowPulse {
  0%, 100% { transform: scale(.86); opacity: .52; }
  50% { transform: scale(1.12); opacity: .95; }
}

@keyframes bkArticleShine {
  0% { left: -60%; opacity: 0; }
  18% { opacity: .75; }
  42% { left: 120%; opacity: .5; }
  100% { left: 120%; opacity: 0; }
}

@keyframes bkProgressFill {
  0% { width: 48%; }
  100% { width: 96%; }
}

@media (max-width: 980px) {
  .bk-nav-inner {
    grid-template-columns: 1fr;
    gap: 12px;
    padding: 14px 0;
  }

  .bk-logo {
    justify-content: center;
  }

  .bk-nav-actions {
    justify-content: center;
  }

  .bk-product-layout {
    grid-template-columns: 1fr;
  }

  .bk-card-grid,
  .bk-testimonial-grid {
    grid-template-columns: 1fr;
  }

  .bk-related-grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

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

@media (max-width: 680px) {
  body {
    padding-bottom: 72px;
  }

  .bk-topbar-inner {
    justify-content: center;
    text-align: center;
  }

  .bk-topbar-right {
    display: none;
  }

  .bk-product-shell,
  .bk-article-glow,
  .bk-faq-wrap,
  .bk-calc-box {
    border-radius: 22px;
    padding: 18px;
  }

  .bk-product-media {
    min-height: 240px;
  }

  .bk-trust-grid,
  .bk-related-grid {
    grid-template-columns: 1fr;
  }

  .bk-cart-item {
    grid-template-columns: 1fr;
  }

  .bk-cart-summary {
    align-items: flex-start;
    flex-direction: column;
  }

  .bk-bottom-nav {
    display: block;
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 110;
    background: rgba(255,255,255,.94);
    backdrop-filter: blur(14px);
    border-top: 1px solid var(--bk-border-soft);
    box-shadow: 0 -10px 26px rgba(4,27,77,.1);
  }

  .bk-bottom-nav-inner {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
  }

  .bk-bottom-nav a {
    text-decoration: none;
    color: var(--bk-blue-dark);
    font-size: 11px;
    font-weight: 950;
    text-align: center;
    padding: 9px 4px;
  }

  .bk-bottom-nav span {
    display: block;
    font-size: 18px;
    line-height: 1;
    margin-bottom: 3px;
  }

  .bk-fixed-cta {
    bottom: 66px;
    grid-template-columns: 1fr 1fr;
  }

  .bk-footer {
    padding-bottom: 150px;
  }
}