:root {
    --prune: #241C30;
    --dark-prune: #100C18;
    --concrete: #F2F2F2;
    --brandeis-blue: #006Af9;
    --coral: #FF7A52;
    --white: #ffffff;
    --glass: rgba(255, 255, 255, 0.05);
    --glass-border: rgba(255, 255, 255, 0.1);
    
    --font-primary: 'Work Sans', sans-serif;
    
    /* Typography per Visual ID */
    --h1-size: 96px;
    --h1-lh: 90px;
    --h2-size: 40px;
    --h2-lh: 50px;
    --h3-size: 26px;
    --h3-lh: 34px;
    --h4-size: 14px;
    --h4-lh: 20px;
    --body-size: 20px;
    --body-lh: 30px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    scrollbar-color: var(--dark-prune) var(--prune) ;

}

body {
    background-color: var(--prune);
    color: var(--concrete);
    font-family: var(--font-primary);
    overflow: hidden; 
    cursor: none; /* Managed by custom cursor */
}

/* --- REACTIVE GRID BACKDROP --- */
#grid-backdrop {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    pointer-events: none;
    z-index: -1;
    background-image: 
        linear-gradient(to right, rgba(255, 255, 255, 0.03) 1px, transparent 1px),
        linear-gradient(to bottom, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
    background-size: 60px 60px;
}

#grid-light {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    pointer-events: none;
    z-index: -1;
    background: radial-gradient(circle 600px at var(--mouse-x) var(--mouse-y), rgba(0, 106, 249, 0.08), transparent 80%);
}

/* --- SCROLL SNAP WRAPPER --- */
main#slide-wrapper {
    height: 100vh;
    overflow-y: auto;
    scroll-snap-type: y mandatory;
    scroll-behavior: smooth;
}

section.slide {
    height: 100vh;
    width: 100%;
    scroll-snap-align: start;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 5vw;
    position: relative;
    overflow: hidden;
}

/* --- TYPOGRAPHY --- */
h1 {
    font-size: var(--h1-size);
    line-height: var(--h1-lh);
    font-weight: 700;
    margin: 2rem 0;
}

h2 {
    font-size: var(--h2-size);
    line-height: var(--h2-lh);
    font-weight: 600;
    color: var(--brandeis-blue);
    margin-bottom: 2.5rem;
}

h3 {
    font-size: var(--h3-size);
    line-height: var(--h3-lh);
    font-weight: 600;
    margin-top: 2rem;
}

p, li, sub {
    font-size: var(--body-size);
    line-height: var(--body-lh);
    font-weight: 400;
}

sup { 
    font-size: 0.45em; 
    vertical-align: super; 
    line-height: 0; 
    margin-left: 2px;
    font-weight: 700;
}

blockquote {
    font-size: var(--body-size);
    line-height: var(--body-lh);
    font-weight: 400;
    border-left: 2px solid var(--brandeis-blue);
    padding-left: 1rem;
    background-color: rgba(255, 255, 255, 0.05);
    border-radius: 4px;
    padding: 1rem;
}
.notes-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}
.notes-header h3 {
    margin:0;
}
#close-notes {
    height: 25px;
    width: 25px;
    border-radius: 25px;
}

.highlight-blue { color: var(--brandeis-blue); }
.highlight-coral { color: var(--coral); }

/* --- NAVIGATION CONTROL --- */
.nav-control {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    padding: 2.5rem 5vw;
    z-index: 100;
    pointer-events: none; /* Let clicks through to slides */
}

.nav-labels {
    pointer-events: auto;
    display: flex;
    gap: 1.5rem;
    overflow-x: auto;
    padding-bottom: 0.5rem;
    justify-content: center;
}

.nav-labels::-webkit-scrollbar { display: none; }

.nav-label-link {
    font-size: 11px;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: rgba(242, 242, 242, 0.4);
    text-decoration: none;
    white-space: nowrap;
    transition: all 0.3s ease;
    position: relative;
}

.nav-label-link.active {
    color: var(--brandeis-blue);
}

.nav-label-link.active::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0;
    width: 100%;
    height: 1px;
    background: var(--brandeis-blue);
}

.nav-utils {
    position: fixed;
    bottom: 2.5rem;
    left: 5vw;
    display: flex;
    gap: 1rem;
    pointer-events: auto;
}

.nav-utils button, .nav-utils a, #back-to-top {
    background: var(--glass);
    border: 1px solid var(--glass-border);
    padding: 0.75rem 1.5rem;
    color: var(--concrete);
    border-radius: 4px;
    text-decoration: none;
    font-size: 11px;
    backdrop-filter: blur(10px);
    text-transform: uppercase;
    letter-spacing: 2px;
    transition: all 0.3s ease;
    cursor: pointer;
}

.nav-utils button:hover, .nav-utils a:hover, #back-to-top:hover {
    background: var(--glass-border);
    border-color: var(--brandeis-blue);
    color: var(--white);
}

#back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2vw;
    font-size: 18px;
    padding: 0.5rem 1rem;
    pointer-events: auto;
    opacity: 1;
    transform: translateY(0);
}

#back-to-top.hidden-btn {
    opacity: 0;
    transform: translateY(20px);
    pointer-events: none;
}

/* --- HERO SPLIT --- */
.hero-split {
    display: flex;
    align-items: center;
    gap: 5vw;
    width: 100%;
}

.hero-img {
    flex: 0 0 45%;
    height: 80vh;
    border-radius: 8px;
    overflow: hidden;
}

.hero-img img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.hero-text {
    flex: 1;
}

/* --- RESPONSIVE NAVIGATION (1500px) --- */
#menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 20px;
    background: transparent;
    border: none;
    cursor: pointer;
    z-index: 101;
    pointer-events: auto;
}

#menu-toggle span {
    display: block;
    width: 100%;
    height: 2px;
    background-color: var(--concrete);
    transition: all 0.4s cubic-bezier(0.77, 0, 0.175, 1);
    transform-origin: left center;
}

#nav-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(5px);
    z-index: 95;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.5s ease;
}

@media (max-width: 1500px) {
    #menu-toggle { display: flex; }
    
    .nav-labels {
        position: fixed;
        top: 0;
        left: -350px;
        width: 350px;
        height: 100vh;
        background: rgba(20, 20, 30, 0.98);
        backdrop-filter: blur(20px);
        padding: 8rem 5vw 4rem 5vw;
        flex-direction: column;
        justify-content: flex-start;
        gap: 2rem;
        transition: left 0.5s cubic-bezier(0.77, 0, 0.175, 1);
        z-index: 100;
        border-right: 1px solid var(--glass-border);
    }
    
    .nav-labels.nav-open { left: 0; }
    
    .nav-label-link { font-size: 16px; width: 100%; }
    
    #nav-overlay.active { opacity: 1; pointer-events: auto; }
    
    /* Toggle X Animation */
    .nav-open-active #menu-toggle span:nth-child(1) { transform: rotate(45deg); width: 28px; }
    .nav-open-active #menu-toggle span:nth-child(2) { opacity: 0; transform: translateX(-10px); }
    .nav-open-active #menu-toggle span:nth-child(3) { transform: rotate(-45deg); width: 28px; }
}

/* --- SPEAKER NOTES --- */
#speaker-notes-panel {
    position: fixed;
    right: -400px;
    top: 0;
    width: 400px;
    height: 100vh;
    background: rgba(20, 20, 30, 0.50);
    backdrop-filter: blur(20px);
    border-left: 1px solid var(--glass-border);
    z-index: 200;
    transition: right 0.5s cubic-bezier(0.77, 0, 0.175, 1);
    padding: 2rem;
}

#speaker-notes-panel.open { right: 0; }

/* --- OTHER COMPONENTS --- */
.slide-content { max-width: 1200px; z-index: 5; width: 100%; }
.bullet-list { margin-top: 2rem; list-style: none; }
.bullet-list li::before { content: '→'; color: var(--brandeis-blue); margin-right: 1rem; }

.demo-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
    margin: 2rem 0;
}

.demo-card {
    background: var(--glass);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 1.25rem;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    position: relative;
    overflow: hidden;
    cursor: pointer;
}

.demo-card:hover {
    transform: translateY(-8px);
    background: rgba(255, 255, 255, 0.08);
    border-color: var(--brandeis-blue);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.3);
}

.demo-img {
    height: 140px;
    width: 100%;
    border-radius: 6px;
    margin-bottom: 1rem;
    object-fit: cover;
    opacity: 0.8;
    transition: opacity 0.3s ease;
}

.demo-card:hover .demo-img {
    opacity: 1;
}

.evidence-footer {
    margin-top: 3rem;
    text-align: center;
    font-size: 1.5rem;
    letter-spacing: 1px;
    opacity: 0;
    transform: translateY(20px);
}

.evidence-footer strong {
    color: var(--brandeis-blue);
    text-transform: uppercase;
}

/* --- FINAL FOOTER --- */
.footer-authorship {
    margin-top: 5rem;
    padding-top: 2rem;
    border-top: 1px solid var(--glass-border);
    font-size: 14px;
    line-height: 1.6;
    color: rgba(242, 242, 242, 0.6);
}

.footer-authorship a {
    color: var(--brandeis-blue);
    text-decoration: none;
}

/* --- CURSOR --- */
#custom-cursor {
    pointer-events: none;
    z-index: 9999;
}

#cursor-point {
    width: 6px;
    height: 6px;
    background: var(--concrete);
    border-radius: 50%;
    position: fixed;
    pointer-events: none;
    z-index: 9999;
    top: 0;
    left: 0;
}

#cursor-circle {
    width: 40px;
    height: 40px;
    border: 1px solid var(--brandeis-blue);
    border-radius: 50%;
    position: fixed;
    pointer-events: none;
    z-index: 9999;
    top: 0;
    left: 0;
}

/* --- TOOLTIP LAUNCHER BUTTONS --- */
.tooltip-launcher {
    display: inline-block;
    margin-top: 0.75rem;
    padding: 0.35rem 0.85rem;
    background: transparent;
    border: 1px solid var(--glass-border);
    border-radius: 4px;
    color: rgba(242, 242, 242, 0.55);
    font-family: var(--font-primary);
    font-size: 11px;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    cursor: pointer;
    transition: all 0.25s ease;
}

.tooltip-launcher:hover {
    background: rgba(0, 106, 249, 0.12);
    border-color: var(--brandeis-blue);
    color: var(--brandeis-blue);
}

/* --- MODAL --- */
#modal-container {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(8px);
    z-index: 500;
    align-items: center;
    justify-content: center;
}

.modal-box {
    background: rgba(20, 16, 38, 0.97);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 2.5rem;
    max-width: 680px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    position: relative;
    box-shadow: 0 30px 80px rgba(0, 0, 0, 0.5);
}

.modal-box h2 {
    font-size: 1.5rem;
    color: var(--brandeis-blue);
    margin-bottom: 1rem;
}

.modal-box p {
    color: rgba(242, 242, 242, 0.8);
    line-height: 1.7;
    font-size: 16px;
}

.modal-box ul {
    margin: 0.75rem 0;
    padding-left: 1.2rem;
    line-height: 1.9;
    color: rgba(242, 242, 242, 0.75);
    font-size: 15px;
}

#close-modal {
    position: absolute;
    top: 1.25rem;
    right: 1.25rem;
    background: transparent;
    border: 1px solid var(--glass-border);
    color: rgba(242, 242, 242, 0.5);
    width: 32px;
    height: 32px;
    border-radius: 50%;
    font-size: 18px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    line-height: 1;
}

#close-modal:hover {
    border-color: var(--brandeis-blue);
    color: var(--concrete);
    background: rgba(0, 106, 249, 0.1);
}