/* ===== Reset & Base ===== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: #333;
    background: #fff;
}

a {
    color: #2a5db0;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* ===== Layout ===== */
.container {
    max-width: 820px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ===== Navigation ===== */
nav {
    border-bottom: 1px solid #ddd;
    padding: 18px 0;
}

nav .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

nav .site-name {
    font-family: Georgia, "Times New Roman", serif;
    font-size: 20px;
    font-weight: normal;
    color: #222;
}

nav .site-name a {
    color: inherit;
}

nav .site-name a:hover {
    text-decoration: none;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 28px;
}

nav ul a {
    color: #555;
    font-size: 15px;
    letter-spacing: 0.3px;
}

nav ul a:hover {
    color: #2a5db0;
    text-decoration: none;
}

nav ul a.active {
    color: #222;
    font-weight: 600;
}

/* ===== Home Page: Bio Section ===== */
.bio {
    display: flex;
    gap: 40px;
    align-items: flex-start;
    padding: 48px 0 40px;
}

.bio-photo {
    flex-shrink: 0;
    width: 220px;
}

.bio-photo img {
    width: 100%;
    border-radius: 4px;
}

.bio-text h1 {
    font-family: Georgia, "Times New Roman", serif;
    font-size: 28px;
    font-weight: normal;
    margin-bottom: 4px;
    color: #222;
}

.bio-text .title {
    font-size: 15px;
    color: #666;
    margin-bottom: 18px;
    line-height: 1.5;
}

.bio-text p {
    margin-bottom: 14px;
}

.bio-text .contact {
    margin-top: 20px;
    font-size: 15px;
    color: #555;
}

.bio-text .contact a {
    font-size: 15px;
}

/* ===== Research Page ===== */
.page-content {
    padding: 44px 0 60px;
}

.page-content h1 {
    font-family: Georgia, "Times New Roman", serif;
    font-size: 26px;
    font-weight: normal;
    color: #222;
    margin-bottom: 32px;
}

.section-heading {
    font-family: Georgia, "Times New Roman", serif;
    font-size: 20px;
    font-weight: normal;
    color: #222;
    margin-bottom: 20px;
    padding-bottom: 8px;
    border-bottom: 1px solid #ddd;
}

.paper {
    margin-bottom: 24px;
    padding-bottom: 24px;
    border-bottom: 1px solid #eee;
}

.paper:last-child {
    border-bottom: none;
}

.paper-title {
    font-weight: 600;
    font-size: 16px;
    margin-bottom: 4px;
}

.paper-title a {
    color: #2a5db0;
}

.paper-authors {
    font-size: 15px;
    color: #555;
    margin-bottom: 3px;
}

.paper-journal {
    font-size: 15px;
    color: #555;
    font-style: italic;
}

.paper-status {
    font-size: 14px;
    color: #777;
    margin-top: 2px;
}

.paper-links {
    margin-top: 6px;
    font-size: 14px;
}

.paper-links a {
    margin-right: 12px;
}

/* ===== Footer ===== */
footer {
    border-top: 1px solid #ddd;
    padding: 20px 0;
    text-align: center;
    font-size: 13px;
    color: #999;
}

/* ===== Mobile ===== */
@media (max-width: 640px) {
    .bio {
        flex-direction: column;
        align-items: center;
        text-align: center;
        gap: 24px;
    }

    .bio-photo {
        width: 180px;
    }

    nav .container {
        flex-direction: column;
        gap: 12px;
    }

    nav ul {
        gap: 20px;
    }

    body {
        padding: 0 16px;
    }

    .page-content {
        padding: 32px 0 48px;
    }

    .section-heading {
        font-size: 18px;
        margin-bottom: 16px;
    }

    .paper {
        margin-bottom: 20px;
        padding-bottom: 20px;
    }

    .paper-title {
        font-size: 15px;
        line-height: 1.4;
    }

    .paper-authors {
        font-size: 14px;
    }

    .paper-journal,
    .paper-status {
        font-size: 13px;
    }
}