.education-header {
    text-align: center;
    margin-bottom: 3rem;
    padding: 2rem;
    background-color: var(--card-bg);
    border-radius: 12px;
    border: 1px solid var(--border-color);
}
.education-header h1 {
    font-family: "Lora", serif;
    color: var(--accent-color);
    margin: 0 0 1rem;
}
.education-header .education-description {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 800px;
    margin: 0 auto;
    line-height: 1.7;
}
.subject-section {
    margin-bottom: 3rem;
}
.subject-section h2 {
    font-family: "Lora", serif;
    font-size: 2.2rem;
    color: var(--text-primary);
    padding-bottom: 0.75rem;
    border-bottom: 3px solid var(--accent-color);
    margin-bottom: 2rem;
}
.chapters-container {
    display: flex;
    overflow-x: auto;
    gap: 1.5rem;
    padding: 1rem 0.5rem 1.5rem;
    scrollbar-width: thin;
    scrollbar-color: var(--accent-color) var(--border-color);
}
.chapters-container::-webkit-scrollbar {
    height: 8px;
}
.chapters-container::-webkit-scrollbar-track {
    background: var(--border-color);
    border-radius: 10px;
}
.chapters-container::-webkit-scrollbar-thumb {
    background-color: var(--accent-color);
    border-radius: 10px;
    border: 2px solid var(--border-color);
}
.chapter-card-link {
    text-decoration: none;
    color: inherit;
    flex: 0 0 280px;
    scroll-snap-align: start;
}
.chapter-card {
    background-color: var(--card-bg);
    border-radius: 12px;
    border: 1px solid var(--border-color);
    box-shadow: 0 4px 12px var(--shadow-color-base);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    display: flex;
    flex-direction: column;
    height: 100%;
    overflow: hidden;
}
.chapter-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 10px 30px var(--shadow-color-base);
}
.chapter-svg-container {
    height: 180px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--blue-light-bg);
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
}
.chapter-svg-container svg {
    width: 100%;
    height: 100%;
    max-width: 100%;
    max-height: 100%;
}
.chapter-content {
    padding: 1.5rem;
    flex-grow: 1;
}
.chapter-title {
    font-family: "Lora", serif;
    font-size: 1.4rem;
    margin: 0 0 0.75rem;
    color: var(--accent-color);
}
.chapter-description {
    font-size: 0.95rem;
    line-height: 1.6;
    color: var(--text-secondary);
    margin: 0;
}
.subject-section h2 {
    font-size: 1.8rem;
}
.chapter-card-link {
    flex: 0 0 250px;
}
@media (max-width: 480px) {
    .education-header .education-description {
        font-size: 1rem;
    }
    .subject-section h2 {
        font-size: 1.5rem;
    }
    .chapter-card-link {
        flex: 0 0 220px;
    }
    .chapter-title {
        font-size: 1.2rem;
    }
    .chapter-description {
        font-size: 0.9rem;
    }
}
.spinner-container {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: row;
    gap: 15px;
    padding: 40px;
    color: var(--text-secondary);
    width: 100%;
}
@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}
.formula-page-container {
    background-color: var(--card-bg);
    padding: 2.5rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    box-shadow: 0 4px 12px var(--shadow-color-base);
}
.formula-section {
    margin-bottom: 2.5rem;
}
.formula-category-title {
    font-family: "Lora", serif;
    font-size: 2rem;
    color: var(--text-primary);
    padding-bottom: 0.75rem;
    border-bottom: 3px solid var(--accent-color);
    margin-bottom: 1.5rem;
}
.formula-list {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
}
.formula-item {
    background-color: var(--primary-bg);
    padding: 1.5rem;
    border-radius: 8px;
    border-left: 5px solid var(--accent-color);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.formula-item:hover {
    transform: translateY(-4px) scale(1.01);
    box-shadow: 0 6px 15px var(--shadow-color-3);
}
.formula-header {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-bottom: 1rem;
}
.formula-title {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--accent-color);
    margin: 0;
}
.formula-expression {
    font-family: "Lora", serif;
    font-size: 1.2rem;
    color: var(--text-primary);
    background-color: var(--card-bg);
    padding: 1rem;
    border-radius: 6px;
    border: 1px solid var(--border-color);
    overflow-x: auto;
    text-align: center;
}
.formula-description {
    font-size: 1rem;
    line-height: 1.6;
    color: var(--text-secondary);
    margin: 0;
}
@media (max-width: 768px) {
    .formula-page-container {
        padding: 1.5rem;
    }
    .formula-category-title {
        font-size: 1.6rem;
    }
    .formula-title {
        font-size: 1.1rem;
    }
    .formula-expression {
        font-size: 1.1rem;
    }
}