* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: #f5f7fb;
    color: #172033;
}
nav {
    display: flex;
    justify-content: center;
    gap: 28px;
    padding: 20px;
    background: rgba(255,255,255,0.85);
    backdrop-filter: blur(12px);
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid rgba(0,0,0,0.06);
}

nav a {
    text-decoration: none;
    color: #172033;
    font-weight: 600;
}

nav a:hover {
    opacity: 0.7;
}
header {
    padding: 64px 24px 40px;
    text-align: center;
}

.logo {
    font-size: 42px;
    font-weight: 800;
    letter-spacing: -1px;
}

.subtitle {
    max-width: 620px;
    margin: 16px auto 0;
    font-size: 20px;
    line-height: 1.5;
    color: #4d5a70;
}

main {
    max-width: 960px;
    margin: 0 auto;
    padding: 24px;
}

.card {
    background: white;
    border-radius: 22px;
    padding: 28px;
    margin-bottom: 20px;
    box-shadow: 0 12px 40px rgba(20, 30, 50, 0.08);
}

.card h2 {
    margin-top: 0;
}

footer {
    text-align: center;
    padding: 40px 24px;
    color: #667085;
}

footer a {
    color: #334155;
    margin: 0 10px;
    text-decoration: none;
}
.app-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
}

.button {
    display: inline-block;
    margin-top: 16px;
    padding: 10px 18px;
    border-radius: 12px;
    background: #172033;
    color: white;
    text-decoration: none;
    font-weight: 600;
}

.button:hover {
    opacity: 0.9;
}