body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif;
    background-color: #f7f1e3; /* cream */
    color: #333;
    line-height: 1.6;
    margin: 0;
    display: flex;
    justify-content: center;
}

.container {
    width: 90%;
    max-width: 1000px;
    padding: 40px 20px;
}

header {
    border-bottom: 1px solid #ddd5c5;
    margin-bottom: 30px;
    padding-bottom: 10px;
}

h1 {
    font-size: 2.2rem;
    color: #222;
    margin-bottom: 5px;
}

h2 {
    font-size: 1.8rem;
    border-bottom: 2px solid #e5dece;
    padding-bottom: 10px;
}

.lecture-card {
    background: #fffdf8;
    border: 1px solid #ded6c6;
    border-radius: 8px;
    padding: 24px;
    margin-bottom: 30px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.04);
    scroll-margin-top: 20px;
}

.lecture-title {
    font-size: 1.4rem;
    font-weight: bold;
    margin: 0;
    color: #111;
}

.meta {
    color: #176b68; /* accent */
    font-weight: 500;
    margin: 8px 0 20px 0;
    font-size: 0.95rem;
}

.section-label {
    font-weight: bold;
    margin-top: 15px;
    display: block;
}

ul {
    list-style: disc;
    padding-left: 20px;
    margin: 10px 0;
}

li {
    margin: 6px 0;
    font-size: 0.95rem;
}

a {
    color: #176b68; /* same accent */
    text-decoration: none;
    font-weight: 500;
}

a:hover {
    text-decoration: underline;
    color: #125653;
}

.code-link {
    font-family: monospace;
    background: #eee9dc;
    padding: 2px 4px;
    border-radius: 3px;
}

.lecture-description {
    margin: 10px 0;
    color: #444;
    line-height: 1.5;
}

html {
    scroll-behavior: smooth;
}

.lecture-card:target {
    border-color: #176b68; /* accent */
    background: #f4faf8;
    box-shadow: 0 0 0 3px rgba(23, 107, 104, 0.15);
}

.permalink {
    margin-left: 8px;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1rem;
    opacity: 0;
    transition: opacity 0.2s ease;
    color: #176b68;
}

.lecture-title:hover .permalink {
    opacity: 0.5;
}

.permalink:hover {
    opacity: 1;
}