:root {
  --blue-dark: #003049;
  --blue-primary: #0077b6;
  --blue-light: #90e0ef;
  --white-pure: #ffffff;
  --ice-bg: #e0fbfc;
  --silver-metal: #adb5bd;
  --border-hard: #00b4d8;
}

body {
  font-family: 'PingFang SC', 'Microsoft YaHei', sans-serif;
  margin: 0;
  padding: 0;
  background-color: var(--ice-bg);
  color: var(--blue-dark);
  line-height: 1.6;
}

/* Typography */
h1, h2, h3 {
  font-weight: 300;
  letter-spacing: 1px;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(145deg, var(--white-pure), var(--silver-metal));
  color: var(--blue-dark);
  border: 1px solid var(--blue-primary);
  padding: 0.75rem 2rem;
  text-decoration: none;
  font-weight: 600;
  border-radius: 0; /* Sharp edges */
  box-shadow: 4px 4px 0 var(--border-hard);
  transition: all 0.2s ease-in-out;
}

.btn:hover {
  transform: translate(2px, 2px);
  box-shadow: 2px 2px 0 var(--border-hard);
}

.btn-primary {
  background: linear-gradient(145deg, var(--blue-primary), var(--blue-dark));
  color: var(--white-pure);
  border: 1px solid var(--blue-light);
}

/* Layout */
.wrapper {
  display: grid;
  grid-template-columns: 1fr;
  gap: 3rem;
}

/* Header */
header {
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(5px);
  border-bottom: 2px solid var(--border-hard);
  z-index: 1000;
  display: grid;
  grid-template-columns: 200px 1fr auto;
  align-items: center;
  padding: 1rem 4rem;
  box-shadow: 0 4px 10px rgba(0,180,216,0.1);
}

nav ul {
  display: grid;
  grid-auto-flow: column;
  gap: 2rem;
  list-style: none;
  margin: 0;
  padding: 0;
  justify-content: center;
}

nav a {
  text-decoration: none;
  color: var(--blue-dark);
  font-weight: 500;
  position: relative;
}

nav a:hover::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--blue-primary);
}

/* Sections */
section {
  padding: 4rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  max-width: 1400px;
  margin: 0 auto;
  width: 100%;
  box-sizing: border-box;
}

.split-screen {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
}

.section-title {
  grid-column: 1 / -1;
  text-align: center;
  font-size: 2.5rem;
  border-bottom: 2px solid var(--border-hard);
  padding-bottom: 1rem;
  margin-bottom: 2rem;
}

/* Grids */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 2rem; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 2rem; }

/* Cards */
.card {
  background: var(--white-pure);
  border: 1px solid var(--border-hard);
  padding: 2rem;
  box-shadow: 6px 6px 0 var(--blue-light);
  display: grid;
  grid-template-rows: auto auto 1fr;
  gap: 1rem;
}

.card-icon {
  width: 48px;
  height: 48px;
  stroke: var(--blue-primary);
  stroke-width: 1;
  fill: none;
}

/* Pricing Special */
.pricing-card {
  text-align: center;
  border-top: 4px solid var(--border-hard);
}
.pricing-card.featured {
  border-top: 4px solid var(--blue-dark);
  transform: scale(1.05);
  box-shadow: 8px 8px 0 var(--silver-metal);
}
.price { font-size: 3rem; font-weight: bold; color: var(--blue-dark); }

/* FAQ */
.faq-item {
  background: var(--white-pure);
  border-left: 4px solid var(--blue-primary);
  padding: 1.5rem;
  margin-bottom: 1rem;
}

/* Footer */
footer {
  background: var(--white-pure);
  border-top: 2px solid var(--border-hard);
  padding: 3rem;
  display: grid;
  grid-template-columns: repeat(4, auto);
  justify-content: center;
  gap: 4rem;
}

footer a {
  color: var(--blue-primary);
  text-decoration: none;
}
footer a:hover { text-decoration: underline; }

.seo-article a, .seo-article a:visited { color: #00b4d8; }


/* Blog Card Grid Styles (Ice & Crystal Theme, Sharp Edges) */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
}
.card {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(144, 224, 239, 0.5);
    border-radius: 0;
    padding: 2rem;
    box-shadow: 0 4px 15px rgba(0, 48, 73, 0.05);
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
}
.card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 25px rgba(0, 119, 182, 0.15);
    border-color: #00b4d8;
}
.card h3 {
    color: #003049;
    margin-bottom: 1rem;
    font-size: 1.2rem;
    line-height: 1.5;
    font-weight: 500;
}
.card p {
    color: #4a5568;
    margin-bottom: 1.5rem;
    font-size: 0.95rem;
    line-height: 1.6;
    flex-grow: 1;
}
.card .btn {
    align-self: flex-start;
    padding: 0.6rem 1.5rem;
    font-size: 0.95rem;
    text-decoration: none;
    border-radius: 0;
    background-color: #0077b6;
    color: #fff;
    transition: background-color 0.3s;
    border: none;
    cursor: pointer;
}
.card .btn:hover {
    background-color: #00b4d8;
}

/* SEO Article and Container Styles */
.article-container {
    max-width: 800px;
    margin: 4rem auto;
    padding: 0 2rem;
    min-height: 70vh;
}

.seo-article {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border: 1px solid var(--blue-light);
    padding: 3rem 4rem;
    box-shadow: 8px 8px 0 var(--ice-bg), 0 4px 15px rgba(0, 48, 73, 0.05);
    border-radius: 0; /* Sharp aesthetic */
}

.seo-article h1 {
    color: var(--blue-primary);
    font-size: 2.2rem;
    margin-bottom: 2rem;
    text-align: center;
    border-bottom: 2px solid var(--border-hard);
    padding-bottom: 1rem;
    font-weight: 300;
}

.seo-article h2 {
    color: var(--blue-dark);
    font-size: 1.6rem;
    margin-top: 2.5rem;
    margin-bottom: 1rem;
    font-weight: 400;
}

.seo-article h3 {
    color: var(--blue-primary);
    font-size: 1.3rem;
    margin-top: 2rem;
    margin-bottom: 0.8rem;
    font-weight: 400;
}

.seo-article p {
    color: #4a5568;
    font-size: 1.05rem;
    line-height: 1.8;
    margin-bottom: 1.5rem;
    letter-spacing: 0.5px;
}

.seo-article p:first-of-type {
    font-size: 1.15rem;
    color: var(--blue-dark);
}

.seo-article a {
    color: var(--border-hard);
    text-decoration: none;
    border-bottom: 1px solid transparent;
    transition: all 0.3s ease;
}

.seo-article a:hover {
    color: var(--blue-primary);
    border-bottom-color: var(--blue-primary);
}

/* Global Link Override to prevent default browser blue/purple */
a { color: #00b4d8; text-decoration: none; }

a:hover { filter: brightness(1.2); }


/* Universal Mobile Nav Fix */
@media (max-width: 991px) {
    header, .top-header, .sticky-nav {
        flex-direction: column !important;
        height: auto !important;
        padding: 15px 10px !important;
    }
    .main-nav, nav, .nav-links, .nav-links ul, nav ul {
        display: flex !important;
        flex-wrap: wrap !important;
        justify-content: center !important;
        gap: 12px !important;
        width: 100% !important;
        margin: 10px 0 !important;
        padding: 0 !important;
    }
    .main-nav a, nav a, .nav-links a {
        font-size: 0.95rem !important;
        padding: 5px !important;
        margin: 0 !important;
    }
    .cta-btn, .nav-cta, .btn, .primary-btn, .primary-cta {
        margin-top: 5px !important;
        width: auto !important;
    }
}