:root {
    --bg-color: #E3E2DD; /* Light Warm Beige */
    --text-color: #111111;
    --border-color: #111111;
    --font-main: 'Helvetica Neue', Helvetica, Arial, sans-serif;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: var(--font-main);
    width: 100%;
    min-height: 100vh;
    padding: 2vw;
    -webkit-font-smoothing: antialiased;
}

/* Wrapper to hold the grid */
.container {
    border: 1px solid var(--border-color);
    margin: 0 auto;
    max-width: 1600px;
    background-color: var(--bg-color);
}

/* Top Navigation */
.top-nav {
    display: flex;
    justify-content: space-between;
    padding: 0.5rem 1rem;
    border-bottom: 1px solid var(--border-color);
    font-size: 0.75rem;
    text-transform: uppercase;
    font-weight: bold;
    letter-spacing: 0.5px;
}

/* Hero Section */
.hero {
    border-bottom: 1px solid var(--border-color);
    text-align: center;
    overflow: hidden;
}

.hero h1 {
    font-size: clamp(3rem, 11vw, 12rem);
    font-weight: 900;
    line-height: 0.85;
    letter-spacing: -0.04em;
    margin: -0.5rem 0; /* Tighten top/bottom */
    color: var(--text-color);
    text-transform: uppercase;
}

.view-toggle {
    padding: 0.5rem 1rem;
    font-size: 0.75rem;
    border-bottom: 1px solid var(--border-color);
}

/* Main Grid */
.b-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-auto-rows: minmax(250px, auto);
}

/* Responsive Grid */
@media (max-width: 1024px) {
    .b-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}
@media (max-width: 600px) {
    .b-grid {
        grid-template-columns: 1fr;
    }
}

.b-block {
    border-right: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
    position: relative;
    background: transparent;
    color: var(--text-color);
    cursor: pointer;
    text-decoration: none;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 2rem;
    transition: background-color 0.2s, color 0.2s;
    font-family: var(--font-main);
    text-align: center;
    border-left: none;
    border-top: none;
    outline: none;
}

/* Fix right/bottom borders for grid */
.b-block:nth-child(4n) { border-right: none; }
@media (max-width: 1024px) {
    .b-block:nth-child(4n) { border-right: 1px solid var(--border-color); }
    .b-block:nth-child(2n) { border-right: none; }
}
@media (max-width: 600px) {
    .b-block { border-right: none !important; }
}

.b-block:hover {
    background-color: var(--text-color);
    color: var(--bg-color);
}

.b-block.bg-dark {
    background-color: var(--text-color);
    color: var(--bg-color);
}
.b-block.bg-dark:hover {
    background-color: var(--bg-color);
    color: var(--text-color);
}

/* Prevent hover inversion for specific large blocks */
.b-block.no-hover:hover {
    background-color: transparent;
    color: var(--text-color);
}
.b-block.bg-dark.no-hover:hover {
    background-color: var(--text-color);
    color: var(--bg-color);
}

/* Grid Spans */
.span-2-col { grid-column: span 2; }
.span-2x2 { grid-column: span 2; grid-row: span 2; }
@media (max-width: 600px) {
    .span-2-col, .span-2x2 { grid-column: span 1; grid-row: span 1; }
}

/* Inner Block Content */
.center-content h2 {
    font-size: clamp(1.5rem, 3vw, 2.5rem);
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: -1px;
}

.huge-text {
    font-size: clamp(2rem, 5vw, 4rem) !important;
    line-height: 0.9;
}

/* Corners */
.corner-label {
    position: absolute;
    bottom: 15px;
    left: 15px;
    font-size: 0.7rem;
    text-align: left;
    text-transform: uppercase;
    line-height: 1.1;
    letter-spacing: 0.08em;
    font-weight: 700;
    pointer-events: none;
    z-index: 10;
    opacity: 0.8;
}

.corner-dot {
    position: absolute;
    bottom: 15px;
    right: 15px;
    font-size: 0.8rem;
    pointer-events: none;
    z-index: 10;
    opacity: 0.8;
}

/* Sub-blocks for Ecosystem */
.ecosystem-container {
    display: flex;
    width: 100%;
    height: 100%;
    align-items: center;
    justify-content: space-around;
    padding-bottom: 2rem; /* space for corner label */
}

.sub-link {
    font-size: clamp(1rem, 2vw, 1.5rem);
    font-weight: 700;
    text-decoration: none;
    color: inherit;
    text-transform: uppercase;
}

.sub-link:hover {
    text-decoration: underline;
}

/* SVG Tangrams */
.tangram {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 150px;
    height: 150px;
    opacity: 0.08; /* Subtle watermark */
    pointer-events: none;
    z-index: 0;
    transition: opacity 0.2s, transform 0.2s;
}

.b-block {
    flex-direction: column;
}

.b-block:hover .tangram {
    transform: translate(-50%, -50%) scale(1.1);
    opacity: 0.15;
}

.center-content, .sub-desc {
    position: relative;
    z-index: 1;
}

.sub-desc {
    font-size: 0.8rem;
    margin-top: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    opacity: 0.7;
}

/* RABBIT HOLES (Full Screen Takeovers) */
.rabbit-hole {
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background-color: var(--text-color);
    color: var(--bg-color);
    z-index: 2000;
    display: flex;
    flex-direction: column;
    transform: translateY(100%);
    transition: transform 0.5s cubic-bezier(0.16, 1, 0.3, 1);
    overflow-y: auto;
    padding: 2vw;
}

.rabbit-hole.active {
    transform: translateY(0);
}

.rh-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    border-bottom: 2px solid var(--bg-color);
    padding-bottom: 1rem;
    margin-bottom: 2rem;
}

.rh-title {
    font-size: clamp(3rem, 8vw, 8rem);
    font-weight: 900;
    line-height: 0.8;
    text-transform: uppercase;
    margin: 0;
}

.rh-close {
    font-size: clamp(1rem, 2vw, 2rem);
    cursor: pointer;
    background: none;
    border: none;
    color: var(--bg-color);
    font-weight: bold;
    text-transform: uppercase;
}

.rh-close:hover {
    opacity: 0.5;
}

.rh-content {
    flex: 1;
    font-size: clamp(1rem, 2vw, 1.5rem);
    line-height: 1.4;
    max-width: 1200px;
}

.rh-footer {
    border-top: 2px solid var(--bg-color);
    padding-top: 2rem;
    margin-top: 2rem;
    display: flex;
    gap: 1rem;
}

.text-body {
    white-space: pre-wrap;
    font-family: var(--font-mono);
}

.os-btn {
    flex: 1;
    background: transparent;
    border: 1px solid var(--bg-color);
    padding: 1rem;
    font-weight: 700;
    cursor: pointer;
    text-transform: uppercase;
    transition: background 0.1s, color 0.1s;
    text-decoration: none;
    text-align: center;
    color: var(--bg-color);
}

.os-btn:hover {
    background: var(--bg-color);
    color: var(--text-color);
}

/* Links & Rows inside Rabbit Hole */
.rh-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 0;
    border-bottom: 1px solid rgba(255,255,255,0.2);
    text-decoration: none;
    color: var(--bg-color);
    transition: background 0.1s;
}

.rh-row:hover {
    background: rgba(255,255,255,0.1);
}

.rh-row:last-child {
    border-bottom: none;
}

.rh-label {
    font-size: clamp(1.2rem, 3vw, 2.5rem);
    font-weight: 800;
    text-transform: uppercase;
    text-decoration: none;
    color: inherit;
}

.rh-val {
    font-size: clamp(1rem, 2vw, 1.5rem);
    font-weight: 400;
}

.small-copy {
    padding: 0.5rem 1.5rem;
    font-size: 1rem;
    font-weight: bold;
    background: var(--bg-color);
    color: var(--text-color);
    border: none;
    cursor: pointer;
    text-transform: uppercase;
}

.small-copy:hover {
    opacity: 0.8;
}

/* Deep Mobile Responsiveness */
@media (max-width: 600px) {
    body {
        padding: 5px;
    }
    
    .top-nav {
        flex-direction: column;
        align-items: center;
        gap: 10px;
        text-align: center;
        padding: 1rem 0;
    }

    .rabbit-hole {
        padding: 1.5rem;
    }
    
    .rh-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }

    .rh-row {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5rem;
    }

    .rh-label {
        font-size: 1.2rem !important; /* Override clamp for tiny screens */
    }
    
    .rh-val {
        font-size: 1rem !important;
    }

    .os-btn {
        padding: 0.8rem;
        font-size: 0.8rem;
    }
    
    .rh-footer {
        flex-direction: column;
        gap: 0.5rem;
    }
}
/* Toast */
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background-color: var(--text-color);
    color: var(--bg-color);
    padding: 1rem 2rem;
    font-weight: 800;
    z-index: 3000;
    transition: transform 0.3s;
}
.toast.show { transform: translateX(-50%) translateY(0); }