@property --bg-start {
    syntax: '<color>';
    inherits: true;
    initial-value: #8cabff;
}

@property --bg-end {
    syntax: '<color>';
    inherits: true;
    initial-value: #7450f6;
}

@property --bg-color {
    syntax: '<color>';
    inherits: true;
    initial-value: #816bf7;
}

:root {
    /* Primary theme colors */
    --bg-color: #816bf7;
    --bg-start: #8cabff;
    --bg-end: #7450f6;

    --text-color: #ffffff;
    --faded-text: rgba(255, 255, 255, 0.4);
    --font-main: 'Inter', system-ui, sans-serif;
    --transition-speed: 0.8s;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    background-color: var(--bg-color);
    background: linear-gradient(135deg, var(--bg-start) 0%, var(--bg-end) 100%);
    color: var(--text-color);
    font-family: var(--font-main);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    padding: 2rem 3rem;
    overflow-x: hidden;
    transition:
        --bg-start var(--transition-speed) ease,
        --bg-end var(--transition-speed) ease,
        --bg-color var(--transition-speed) ease;
}

/* Header */
header {
    margin-bottom: 2rem;
    flex-shrink: 0;
}

.top-nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-weight: 600;
    font-size: 1.1rem;
}

.nav-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    padding: 0.6rem;
    border: 1.5px solid rgba(255, 255, 255, 0.4);
    border-radius: 50%;
    color: white;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    width: 42px;
    height: 42px;
}

.nav-button:hover {
    background: white;
    color: #7450f6; /* Fallback primary */
    border-color: white;
    transform: translateY(-1px);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

.logo-link {
    display: flex;
    align-items: center;
}

.top-links a,
.logo a {
    text-decoration: none;
    color: var(--text-color);
    opacity: 0.9;
}

/* Slides Container (Accordion) */
main.slides-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center; /* Centers the whole block vertically if content is short */
    max-width: 900px;
    margin-left: 0; /* Align left */
}

.main-logo {
    width: 200px;
    height: auto;
    filter: brightness(0) invert(1);
    opacity: 1;
    display: inline-block;
    vertical-align: middle;
}

/* Individual Slide */
.slide {
    margin-bottom: 0.5rem;
    transition: all var(--transition-speed) ease;
    cursor: pointer;
}

.slide-header {
    display: flex;
    align-items: baseline;
    gap: 1rem;
    opacity: 0.5;
    transition: opacity 0.3s ease;
}

.slide-header:hover {
    opacity: 0.8;
}

.slide.active .slide-header {
    opacity: 1;
    cursor: default;
}

.slide-num {
    font-weight: 700;
    font-size: 1.5rem;
    width: 3rem; /* Fixed width for alignment */
    flex-shrink: 0;
}

.slide-title {
    font-size: 1.5rem; /* Default small size for title if visible, or hide it */
    font-weight: 700;
    display: none; /* By default hide title for inactive items to match image 2 exactly? */
    /* Actually image 2 shows inactive numbers WITHOUT titles. */
}

/* Active State Styles */
.slide.active .slide-title {
    display: block; /* Show title when active */
    font-size: 2rem;
    line-height: 1.2;
}

.slide-body {
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition:
        max-height var(--transition-speed) ease,
        opacity var(--transition-speed) ease,
        margin var(--transition-speed) ease;
    margin-left: 4rem; /* Indent body text to align with title */
}

.slide.active .slide-body {
    max-height: 500px; /* Arbitrary large height */
    opacity: 1;
    margin-top: 1rem;
    margin-bottom: 2rem; /* Space after active item */
}

.text-content p {
    font-size: 2rem;
    line-height: 1.4;
    font-weight: 500;
    max-width: 800px;
}

/* Footer */
footer {
    margin-top: auto;
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    padding-top: 2rem;
    flex-shrink: 0;
}

.copyright {
    text-align: center;
    flex: 1;
}

.copyright p {
    color: var(--faded-text);
    font-size: 0.9rem;
    font-weight: 500;
    margin: 0;
}

.bottom-nav a {
    text-decoration: none;
    color: var(--faded-text);
    font-weight: 700;
    font-size: 1.1rem;
}

.nav-dot {
    width: 42px;
    height: 42px;
    border-radius: 50%;
    background-color: rgba(255, 255, 255, 0.2);
    border: 2px solid rgba(255, 255, 255, 0.5);
    color: white;
    cursor: pointer;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    display: flex;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(5px);
}

.nav-dot:hover {
    transform: scale(1.1) rotate(5deg);
    background-color: white;
    color: #7450f6; /* Contrasts with white background */
    border-color: white;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.nav-dot svg {
    transition: transform 0.4s ease;
}

.nav-dot:hover svg {
    transform: translateY(-2px);
}

/* Responsive */
@media (max-width: 768px) {
    body {
        padding: 1.5rem;
    }

    .slide.active .slide-title {
        font-size: 1.5rem;
    }

    .text-content p {
        font-size: 1.25rem;
    }

    .slide-num {
        font-size: 1.2rem;
        width: 2.5rem;
    }

    .slide-body {
        margin-left: 0; /* Remove indent on mobile */
    }
}