/* About page styles */

/* Sticky section nav */
.about-nav {
    position: sticky;
    top: 0;
    z-index: 100;
    background: var(--bg);
    border-bottom: 1px solid #e0e0e0;
    display: flex;
    justify-content: center;
    gap: 0;
    padding: 0;
    max-width: 800px;
    margin: 0 auto;
}
.about-nav-back {
    padding: 12px 14px 12px 16px;
    text-decoration: none;
    color: var(--text-muted);
    font-size: 1.1em;
    border-bottom: 2px solid transparent;
    border-right: 1px solid #e0e0e0;
    margin-right: 4px;
    transition: color 0.2s;
}
.about-nav-back:hover {
    color: var(--accent);
}
.about-nav-tab {
    padding: 12px 20px;
    text-decoration: none;
    color: var(--text-muted);
    font-size: 0.95em;
    border-bottom: 2px solid transparent;
    transition: color 0.2s, border-color 0.2s;
    white-space: nowrap;
}
.about-nav-tab:hover {
    color: var(--text-dark);
}
.about-nav-tab.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
}

/* Section containers */
.about-page-section {
    scroll-margin-top: 48px;
}

.about-hero {
    text-align: center;
    padding: 60px 20px 40px;
    max-width: 800px;
    margin: 0 auto;
}
.about-hero h2 {
    font-size: 2em;
    color: var(--accent);
    margin-bottom: 12px;
}
.about-hero .tagline {
    font-size: 1.1em;
    color: var(--text-muted);
    margin: 0;
    line-height: 1.5;
}

.about-section {
    max-width: 800px;
    margin: 0 auto;
    padding: 50px 20px;
    border-bottom: 1px solid #e0e0e0;
}
.about-section:last-of-type {
    border-bottom: none;
}
.about-section h3 {
    font-size: 1.4em;
    color: var(--accent);
    margin: 0 0 12px;
}
.about-section p {
    font-size: 1em;
    line-height: 1.6;
    color: var(--text-dark);
    margin: 0 0 20px;
}

/* Scroll-reveal animation */
.reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Images within sections get a staggered delay */
.about-img {
    display: block;
    width: 100%;
    max-width: 700px;
    margin: 16px auto;
    border-radius: 8px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.10);
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.7s ease 0.2s, transform 0.7s ease 0.2s;
    cursor: zoom-in;
}
.visible .about-img {
    opacity: 1;
    transform: translateY(0);
}

/* Lightbox overlay */
.lightbox {
    display: none;
    position: fixed;
    inset: 0;
    z-index: 9999;
    background: rgba(0, 0, 0, 0.85);
    cursor: zoom-out;
    align-items: center;
    justify-content: center;
    padding: 24px;
}
.lightbox.active {
    display: flex;
}
.lightbox img {
    max-width: 95vw;
    max-height: 92vh;
    border-radius: 8px;
    box-shadow: 0 4px 40px rgba(0,0,0,0.5);
    object-fit: contain;
}
.lightbox-close {
    position: fixed;
    top: 16px;
    right: 20px;
    color: #fff;
    font-size: 32px;
    line-height: 1;
    cursor: pointer;
    z-index: 10000;
    opacity: 0.7;
    transition: opacity 0.2s;
    background: none;
    border: none;
    padding: 4px 8px;
}
.lightbox-close:hover {
    opacity: 1;
}

/* Example links */
.about-example {
    font-size: 0.9em;
    color: var(--text-muted);
    margin: -12px 0 20px;
}
.about-example a {
    color: var(--primary-dark);
}

/* Physics parameter lists (reused from modal styles) */
.about-section .param-list {
    margin: 0 0 12px 0;
    padding-left: 0;
    list-style: none;
}
.about-section .param-list li {
    margin-bottom: 8px;
    padding-left: 16px;
    position: relative;
    font-size: 0.95em;
    line-height: 1.5;
    color: var(--text-dark);
}
.about-section .param-list li::before {
    content: "\2022";
    position: absolute;
    left: 0;
    color: var(--primary);
}
.about-section .param-name {
    font-weight: 600;
    color: #333;
}
.about-section h4 {
    font-size: 1.1em;
    color: var(--text-dark);
    margin: 24px 0 8px;
}

/* Equation block */
.about-equation {
    text-align: center;
    font-family: "Times New Roman", Georgia, serif;
    font-size: 1.05em;
    background: #f0f0f2;
    padding: 16px 20px;
    border-radius: 8px;
    margin: 16px auto;
    max-width: 700px;
    line-height: 1.6;
    color: var(--text-dark);
    overflow-x: auto;
}

/* CTA section */
.about-cta {
    text-align: center;
    padding: 50px 20px;
    max-width: 800px;
    margin: 0 auto;
}
.about-cta a {
    display: inline-block;
    padding: 14px 36px;
    background: var(--primary-gradient);
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-size: 1.1em;
    font-weight: 600;
    transition: opacity 0.2s;
}
.about-cta a:hover {
    opacity: 0.9;
}

/* Mobile adjustments */
@media (max-width: 600px) {
    .about-nav {
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        justify-content: flex-start;
    }
    .about-nav-tab {
        padding: 10px 14px;
        font-size: 0.85em;
    }
    .about-hero {
        padding: 40px 16px 24px;
    }
    .about-hero h2 {
        font-size: 1.5em;
    }
    .about-hero .tagline {
        font-size: 1em;
    }
    .about-section {
        padding: 32px 16px;
    }
    .about-section h3 {
        font-size: 1.2em;
    }
    .about-section p {
        font-size: 0.95em;
    }
    .about-equation {
        font-size: 0.9em;
        padding: 12px 14px;
    }
    .about-cta {
        padding: 32px 16px;
    }
}