/* Modern Enterprise Light Theme */
body { background-color: #f4f7f6; color: #2c3e50; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; line-height: 1.8; }

h1, h2, h3, h4 { color: #1a252f; font-weight: 800; margin-top: 2rem; margin-bottom: 1rem; letter-spacing: -0.5px; }
h2 { border-bottom: 2px solid #ecf0f1; padding-bottom: 10px; }
h3 { font-size: 1.3rem; color: #1a5276; }

a { color: #1a5276; text-decoration: none; font-weight: 600; }
a:hover { color: #154360; text-decoration: underline; } 

/* Crisp White Navbar */
.navbar { background-color: #ffffff !important; box-shadow: 0 2px 15px rgba(0,0,0,0.05); padding: 15px 0; }
.navbar-brand { color: #2c3e50 !important; font-weight: 800; font-size: 1.4rem; display: flex; align-items: center; gap: 12px; }

.nav-link { color: #34495e !important; font-weight: 600; text-transform: uppercase; font-size: 0.85rem; letter-spacing: 0.5px; }
.nav-link:hover, .nav-link.active { color: #1a5276 !important; }
.dropdown-menu { border: none; box-shadow: 0 10px 30px rgba(0,0,0,0.1); border-radius: 8px; }
.dropdown-item { color: #2c3e50; }

/* Soft Gradient Hero Section */
.hero-banner { background: linear-gradient(135deg, #e0eafc 0%, #cfdef3 100%); padding: 140px 0 90px; text-align: center; border-bottom: 1px solid #d1d9e6; }
.hero-banner h1 { font-size: 2.5rem; color: #1a252f; text-shadow: 0 1px 2px rgba(255,255,255,0.8); max-width: 900px; margin: 0 auto; line-height: 1.3; }

/* High-Conversion Download Button */
.btn-dl-primary { background-color: #145c32; color: #ffffff !important; padding: 18px 45px; font-size: 1.25rem; font-weight: 700; border-radius: 50px; display: inline-block; margin-top: 25px; box-shadow: 0 8px 20px rgba(20, 92, 50, 0.3); transition: all 0.3s ease; }
.btn-dl-primary:hover { background-color: #0d4022; transform: translateY(-3px); box-shadow: 0 12px 25px rgba(20, 92, 50, 0.4); text-decoration: none; }

/* Clean White Content Container */
.main-card { background: #ffffff; border-radius: 12px; box-shadow: 0 5px 30px rgba(0,0,0,0.04); padding: 50px; margin-top: -40px; margin-bottom: 50px; border: 1px solid #edf2f7; position: relative; z-index: 10; }

/* Feature Grid Layout */
.feature-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 25px; margin: 30px 0; }
.feature-item { background: #f8fafc; padding: 25px; border-radius: 8px; border-left: 5px solid #1a5276; }
.feature-item h3 { margin-top: 0; margin-bottom: 15px; }
.feature-item p { margin-bottom: 0; }

/* Typography & Lists */
ul, ol { padding-left: 1.5rem; margin-bottom: 1.5rem; color: #34495e; }
li { margin-bottom: 0.6rem; }
p { color: #34495e; }

/* Adsterra SEO Safe Containers */
.ad-wrapper { background: #f8fafc; border: 1px dashed #cbd5e1; display: flex; justify-content: center; align-items: center; margin: 35px auto; position: relative; border-radius: 6px; }
.ad-leaderboard { min-height: 90px; width: 100%; max-width: 728px; }
.ad-rectangle { min-height: 250px; width: 100%; max-width: 300px; float: right; margin: 0 0 20px 30px; }
.ad-label { position: absolute; top: -20px; right: 0; font-size: 10px; color: #475569; text-transform: uppercase; letter-spacing: 1px; font-weight: 600; }

/* Dark Corporate Footer */
footer { background-color: #1a252f; padding: 50px 0 30px; color: #95a5a6; font-size: 0.9rem; }
footer a { color: #ecf0f1; margin: 0 12px; font-weight: 400; }
footer a:hover { color: #3498db; }

/* Accessibility utilities */
.visually-hidden-focusable { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.visually-hidden-focusable:focus { position: static; width: auto; height: auto; padding: 1rem; margin: 0; overflow: visible; clip: auto; white-space: normal; background-color: #ffffff; color: #2c3e50; z-index: 10000; }

@media (max-width: 768px) {
.main-card { padding: 30px 20px; margin-top: 0; border-radius: 0; }
.hero-banner h1 { font-size: 2rem; }
.ad-rectangle { float: none; margin: 30px auto; }
}