* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: "Poppins", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: #faf7f2;
    color: #2a1b12;
}

/* Cover page */
.bo-cover {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: radial-gradient(circle at top left, #fdf0da 0, #f8e0c5 40%, #f7e4dd 100%);
    padding: 40px 16px;
    page-break-after: always;
}

.bo-cover-inner {
    max-width: 800px;
    text-align: center;
    padding: 24px 20px 28px;
    background: rgba(255, 253, 248, 0.95);
    border-radius: 20px;
    border: 1px solid #f0e2cc;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
}

.bo-org {
    font-size: 0.95rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: #5a3a24;
    margin: 0 0 4px;
}

.bo-conf-label {
    font-size: 1rem;
    font-weight: 500;
    color: #8b0000;
    margin: 0 0 8px;
}

.bo-title {
    font-family: "Playfair Display", "Georgia", serif;
    font-size: 1.8rem;
    margin: 6px 0 10px;
    color: #3d1b15;
}

.bo-subtitle {
    font-size: 1.2rem;
    font-weight: 500;
    color: #6a4125;
    margin: 0 0 12px;
}

.bo-meta {
    font-size: 0.95rem;
    margin-bottom: 12px;
}

.bo-meta p {
    margin: 2px 0;
}

.bo-note {
    font-size: 0.9rem;
    color: #5e4631;
    margin: 6px 0 0;
}

/* General sections */
.bo-section {
    max-width: 900px;
    margin: 24px auto;
    padding: 0 16px;
}

.bo-section h2 {
    font-family: "Playfair Display", "Georgia", serif;
    font-size: 1.4rem;
    margin: 0 0 6px;
    color: #4a1c1c;
}

.bo-section p {
    margin: 0 0 8px;
}

/* Table of contents */
.bo-toc {
    font-size: 0.95rem;
    margin-top: 4px;
}

.bo-toc-item {
    margin: 3px 0;
}

.bo-toc-item a {
    color: #8b0000;
    text-decoration: none;
}

.bo-toc-item a:hover {
    text-decoration: underline;
}

/* Abstracts layout */
.bo-abstracts-root {
    max-width: 900px;
    margin: 8px auto 32px;
    padding: 0 16px;
}

/* Language section */
.bo-lang-section {
    page-break-before: always;
}

.bo-lang-section:first-of-type {
    page-break-before: auto;
}

.bo-lang-heading {
    font-family: "Playfair Display", "Georgia", serif;
    font-size: 1.4rem;
    margin: 16px 0 4px;
    color: #3b1812;
}

.bo-lang-sub {
    font-size: 0.85rem;
    color: #6b4b30;
    margin: 0 0 10px;
}

/* Each abstract block */
.bo-abstract-card {
    background: #fffdf8;
    border-radius: 14px;
    border: 1px solid #f0e2cc;
    padding: 10px 12px 12px;
    margin-bottom: 10px;
    page-break-inside: avoid;
}

.bo-abstract-meta-line {
    display: flex;
    flex-wrap: wrap;
    gap: 8px 12px;
    font-size: 0.8rem;
    margin-bottom: 4px;
    color: #6b4b30;
}

.bo-meta-label {
    font-weight: 600;
}

.bo-id {
    font-weight: 600;
    color: #8b0000;
}

.bo-abstract-title {
    font-size: 1rem;
    font-weight: 600;
    margin: 2px 0 4px;
    color: #3a2516;
}

.bo-abstract-authors {
    font-size: 0.9rem;
    font-style: italic;
    margin: 0 0 4px;
    color: #4a3929;
}

.bo-abstract-category {
    font-size: 0.8rem;
    margin: 0 0 6px;
    color: #36522a;
}

.bo-abstract-body {
    font-size: 0.9rem;
    line-height: 1.45;
    color: #3a2a1a;
}

/* Placeholder style when full text not added */
.bo-abstract-body.placeholder {
    font-style: italic;
    color: #8a6e4a;
}

/* Footer */
.bo-footer {
    border-top: 1px solid #e6d0b9;
    padding: 10px 16px 16px;
    text-align: center;
    font-size: 0.8rem;
    color: #6a4a35;
}

/* Print styles */
@media print {
    body {
        background: #ffffff;
    }

    .bo-cover-inner {
        box-shadow: none;
    }

    .bo-footer {
        position: fixed;
        bottom: 0;
        left: 0;
        right: 0;
    }

    a {
        text-decoration: none;
    }
}

@media (max-width: 600px) {
    .bo-title {
        font-size: 1.4rem;
    }

    .bo-cover-inner {
        padding: 16px 14px 18px;
    }
}