To keep your blog looking professional yet inviting, this stylesheet focuses on typography and spacing. I’ve used a "Disney-adjacent" color palette—incorporating a deep royal blue and a clean gold accent—without making it look cluttered.

Since you already have the HTML, you can save this code as style.css in the same folder as your index.html.

The CSS Stylesheet (style.css)
CSS

/* Base Styles */
body {
    font-family: 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.7;
    color: #2c3e50;
    background-color: #f9f9f9;
    margin: 0;
    padding: 0;
}

.container {
    max-width: 850px;
    margin: 40px auto;
    padding: 20px;
    background: #ffffff;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
    border-radius: 8px;
}

/* Header & Typography */
header {
    text-align: center;
    border-bottom: 3px solid #0066cc; /* Royal Blue */
    margin-bottom: 30px;
    padding-bottom: 20px;
}

h1 {
    color: #0066cc;
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

h2 {
    color: #34495e;
    border-left: 5px solid #ffcc00; /* Gold Accent */
    padding-left: 15px;
    margin-top: 30px;
}

/* Post List Styles */
.post-list {
    list-style-type: none;
    padding: 0;
}

.post-list li {
    background: #ffffff;
    border: 1px solid #e1e1e1;
    border-radius: 6px;
    margin-bottom: 15px;
    padding: 20px;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

/* Hover effect for blog posts */
.post-list li:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.1);
    border-color: #0066cc;
}

.post-list h3 {
    margin: 0 0 10px 0;
}

.post-list a {
    text-decoration: none;
    color: #0066cc;
    font-weight: bold;
}

.post-list a:hover {
    color: #004080;
    text-decoration: underline;
}

/* Footer */
footer {
    text-align: center;
    font-size: 0.9rem;
    color: #7f8c8d;
    margin-top: 50px;
    padding: 20px;
}