*{margin:0;padding:0;box-sizing:border-box}body{font-family:Segoe UI,Tahoma,Geneva,Verdana,sans-serif;line-height:1.6;color:#333;background-color:#f5f7fa}.container{max-width:1200px;margin:0 auto;padding:0 20px}a{text-decoration:none}.header{background:#fff;box-shadow:0 2px 10px #0000001a;position:fixed;width:100%;top:0;z-index:1000;height:80px}.header .container{display:flex;justify-content:space-between;align-items:center;padding:1rem 20px;height:100%}.nav-brand h2{color:#2563eb;font-size:1.8rem;font-weight:700}.nav-brand h2 a{color:inherit;text-decoration:none}.nav-menu{display:flex;align-items:center;gap:2rem}.nav-menu a{text-decoration:none;color:#64748b;font-weight:500;transition:color .3s ease}.nav-menu a:hover,.nav-menu a.active{color:#2563eb}.main-content{margin-top:80px;min-height:calc(100vh - 80px)}.btn-primary{background:linear-gradient(135deg,#2563eb,#1d4ed8);color:#fff;border:none;padding:.75rem 1.5rem;border-radius:8px;font-weight:600;cursor:pointer;transition:all .3s 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