/* sim-ai.org — Horizontal Ridge Walk */

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

:root {
    --deep-umber: #4a2612;
    --burnt-sienna: #c4622a;
    --warm-sand: #d4c5a9;
    --slate-khaki: #8a7b66;
    --dark-earth: #3d2e1a;
    --near-black: #2d231a;
    --golden-hour: #f5b870;
    --amber-accent: #ff9f43;
}

html, body {
    height: 100vh;
    overflow-x: auto;
    overflow-y: hidden;
    background: var(--near-black);
    font-family: 'DM Sans', sans-serif;
    color: var(--warm-sand);
    cursor: ew-resize;
}

/* Horizontal scroll container */
.ridge {
    display: flex;
    width: 500vw;
    height: 100vh;
}

/* Panels */
.panel {
    position: relative;
    width: 100vw;
    height: 100vh;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.panel-content {
    position: relative;
    z-index: 2;
    padding: 4rem;
    max-width: 800px;
}

/* Grain overlay */
.grain-overlay {
    position: absolute;
    inset: 0;
    z-index: 1;
    opacity: 0.04;
    pointer-events: none;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* Panel backgrounds */
.panel-summit {
    background: linear-gradient(135deg, var(--near-black) 0%, var(--dark-earth) 50%, #1a1410 100%);
}

.panel-ridge {
    background: linear-gradient(135deg, var(--dark-earth) 0%, #2a1f15 50%, var(--near-black) 100%);
}

.panel-valley {
    background: linear-gradient(135deg, #1a1410 0%, var(--near-black) 50%, var(--dark-earth) 100%);
}

.panel-treeline {
    background: linear-gradient(135deg, var(--near-black) 0%, #1f1a14 50%, var(--dark-earth) 100%);
}

.panel-base {
    background: linear-gradient(135deg, var(--dark-earth) 0%, var(--near-black) 100%);
}

/* Typography */
.wordmark {
    font-family: 'Space Grotesk', sans-serif;
    font-weight: 700;
    font-size: clamp(2.8rem, 7vw, 6rem);
    line-height: 1.08;
    letter-spacing: -0.02em;
    color: var(--warm-sand);
    margin-bottom: 1rem;
}

.tagline {
    font-family: 'DM Sans', sans-serif;
    font-size: clamp(1rem, 2vw, 1.4rem);
    font-weight: 400;
    color: var(--slate-khaki);
    margin-bottom: 3rem;
}

.panel-heading {
    font-family: 'Space Grotesk', sans-serif;
    font-weight: 700;
    font-size: clamp(2.2rem, 5vw, 4.5rem);
    line-height: 1.08;
    letter-spacing: -0.02em;
    color: var(--warm-sand);
    margin-bottom: 2rem;
}

.body-text {
    font-family: 'DM Sans', sans-serif;
    font-size: 1.05rem;
    line-height: 1.7;
    color: var(--slate-khaki);
    max-width: 480px;
    margin-bottom: 2rem;
}

.mono {
    font-family: 'Space Mono', monospace;
    font-size: 0.75rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

/* Data blocks */
.data-block, .contact-block {
    margin: 2rem 0;
}

.data-row {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    padding: 0.6rem 0;
    border-bottom: 1px solid rgba(212, 197, 169, 0.1);
    max-width: 400px;
}

.data-row .label {
    color: var(--slate-khaki);
}

.data-row .value {
    color: var(--golden-hour);
}

/* Elevation markers */
.elevation-marker {
    margin-top: 2rem;
    padding: 0.5rem 1rem;
    border-left: 2px solid var(--burnt-sienna);
}

.elevation-marker .mono {
    color: var(--burnt-sienna);
}

/* Terrain SVGs */
.terrain-iso {
    margin: 2rem 0;
}

.iso-mountain {
    width: 100%;
    max-width: 400px;
    height: auto;
}

.iso-ridge-svg {
    width: 100%;
    max-width: 500px;
    height: auto;
}

/* Contour map */
.contour-map {
    margin: 2rem 0;
}

.contour-svg {
    width: 100%;
    max-width: 350px;
    height: auto;
    animation: contour-pulse 8s ease-in-out infinite;
}

@keyframes contour-pulse {
    0%, 100% { opacity: 0.8; }
    50% { opacity: 1; }
}

/* Grid visual (panel 3) */
.grid-visual {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 4px;
    max-width: 300px;
    margin-top: 2rem;
}

.grid-cell {
    width: 100%;
    aspect-ratio: 1;
    background: var(--burnt-sienna);
    opacity: 0.3;
    transition: opacity 0.6s ease, background-color 0.6s ease;
}

.grid-cell.active {
    opacity: 1;
    background: var(--golden-hour);
}

/* Wordmark end */
.wordmark-end {
    font-family: 'Space Grotesk', sans-serif;
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--slate-khaki);
    margin-top: 3rem;
    opacity: 0.5;
}

/* Progress bar */
.progress-bar {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100vw;
    height: 3px;
    background: rgba(45, 35, 26, 0.5);
    z-index: 100;
}

.progress-fill {
    height: 100%;
    width: 0%;
    background: linear-gradient(90deg, var(--burnt-sienna), var(--golden-hour));
    transition: width 0.1s linear;
}

/* Elevation ticker */
.elevation-ticker {
    position: fixed;
    top: 2rem;
    right: 2rem;
    z-index: 100;
    padding: 0.5rem 1rem;
    background: rgba(45, 35, 26, 0.7);
    border: 1px solid rgba(196, 98, 42, 0.3);
    backdrop-filter: blur(4px);
}

.elevation-ticker .mono {
    color: var(--golden-hour);
}

/* Panel reveal animations */
.panel-content {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.panel.in-view .panel-content {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive */
@media (max-width: 768px) {
    .panel-content {
        padding: 2rem;
    }
    
    .ridge {
        width: 500vw;
    }
}