:root {
    --accent: #1fd5a7;
    --accent-hover: #1fd5a7;
    --accent-active: #83d3b7;
    --bg-dark: #202020;
    --panel-bg: #303030;
    --text-dark: #f8f8f8;
    --text-muted: #b9b9b9;
    --border: #4a4a4a;
}

* { box-sizing: border-box; }
body { 
    margin: 0; 
    padding: 0; 
    font-family: 'Inter', sans-serif; 
    line-height: 1.5;
    letter-spacing: 0.01em;
    background-color: var(--bg-dark); 
    color: white;
}

:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

body:has(canvas) { overflow: hidden; }

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* Navigation */
nav {
    position: fixed; top: 20px; left: 50%; transform: translateX(-50%);
    display: flex; gap: 8px; background: var(--panel-bg);
    padding: 6px; border-radius: 40px; box-shadow: 0 10px 30px rgba(0,0,0,0.4); z-index: 1000;
}

nav a { 
    text-decoration: none; color: var(--text-dark); 
    padding: 10px 20px; font-weight: 600; font-size: 0.95rem;
    border-radius: 30px; transition: all 0.2s ease;
}
nav a.active { background: var(--accent-active); color: #202020; }
nav a:hover:not(.active) { background: var(--accent); color: #202020; }

/* UI Panel */
#ui-panel {
    position: absolute; top: 90px; left: 20px;
    background: var(--panel-bg); padding: 24px;
    border-radius: 16px; color: var(--text-dark);
    width: 320px; z-index: 10;
    box-shadow: 0 20px 40px rgba(0,0,0,0.25);
    max-height: calc(100vh - 120px); overflow-y: auto;
    transition: width 0.2s ease, padding 0.2s ease;
    scrollbar-width: auto;
    scrollbar-color: var(--accent-active) #3a3a3a;
}

#ui-panel::-webkit-scrollbar {
    width: 5px;
}
#ui-panel::-webkit-scrollbar-track {
    background: #3a3a3a;
    border-radius: 999px;
}
#ui-panel::-webkit-scrollbar-thumb {
    background: var(--accent-active);
    border-radius: 999px;
    border: 2px solid #3a3a3a;
}
#ui-panel::-webkit-scrollbar-thumb:hover {
    background: var(--accent-hover);
}

#ui-panel header { margin-bottom: 20px; }
h2 { 
    margin: 0; font-size: 1rem; text-transform: uppercase; 
    letter-spacing: 1px; color: var(--text-muted);
    border-bottom: 1px solid var(--border); padding-bottom: 10px;
}

.param-group { margin-bottom: 16px; }
.param-group label { 
    display: block; font-size: 0.84rem; font-weight: 600; 
    margin-bottom: 8px; color: var(--text-dark); 
}

/* Custom Inputs */
.input-row { display: flex; align-items: center; gap: 12px; }

input[type="range"] {
    flex-grow: 1; -webkit-appearance: none; appearance: none; height: 4px;
    background: #525252; border-radius: 2px;
}
input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none; width: 14px; height: 14px;
    background: var(--accent); border-radius: 50%; cursor: pointer;
    transition: transform 0.1s ease;
}
input[type="range"]::-webkit-slider-thumb:hover { transform: scale(1.2); }

input[type="number"] {
    width: 65px; padding: 6px; border: 1px solid var(--border);
    border-radius: 6px; font-family: inherit; font-size: 0.85rem;
    text-align: center; background: #3a3a3a; color: var(--text-dark);
    appearance: textfield;
    -moz-appearance: textfield;
}

input[type="number"]::-webkit-outer-spin-button,
input[type="number"]::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

.unit-field {
    display: inline-flex;
    align-items: baseline;
    justify-content: flex-end;
    gap: 0.35em;
    width: 80px;
    flex: 0 0 auto;
    padding: 6px 8px;
    border: 1px solid var(--border);
    border-radius: 6px;
    background: #3a3a3a;
    line-height: 1;
}

.unit-field input[type="number"] {
    width: auto;
    min-width: 0;
    flex: 1 1 auto;
    padding: 0;
    border: 0;
    border-radius: 0;
    background: transparent;
    text-align: right;
    font-size: 0.85rem;
    line-height: inherit;
}

.unit-inline {
    flex: 0 0 auto;
    color: var(--text-muted);
    font-size: 0.78rem;
    line-height: inherit;
    pointer-events: none;
}

.unit-field-compact {
    width: 60px;
    padding: 6px 6px;
}

.unit-field-phantom {
    width: 72px;
    padding: 6px 7px;
}

.unit-field-degree {
    gap: 0.15em;
}

select {
    width: 100%; padding: 10px; border-radius: 8px;
    border: 1px solid var(--border); background: #3a3a3a;
    color: var(--text-dark); font-size: 0.9rem; cursor: pointer;
}

/* Collapsible section menu */
.panel-collapse-btn {
    position: static;
    display: block;
    width: 70%;
    margin: 0 auto 12px auto;
    border: 0;
    background: transparent;
    border-radius: 6px;
    color: var(--text-dark);
    height: 28px;
    cursor: pointer;
    font-weight: 700;
    padding: 0;
}

.menu-section {
    margin-bottom: 10px;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: #303030;
}

.menu-section > summary {
    list-style: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px;
    font-size: 0.95rem;
    font-weight: 600;
}
.menu-section > summary .label-text {
    flex: 1 1 auto;
    min-width: 0;
    text-align: left;
}
#ui-panel input[type="checkbox"] {
    width: 14px;
    height: 14px;
    cursor: pointer;
    accent-color: var(--accent);
    flex-shrink: 0;
}

.menu-section > summary .menu-summary-checkbox {
    flex: 0 0 auto;
    margin-left: auto;
}
.menu-section > summary::-webkit-details-marker { display: none; }

.menu-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 33px;
    height: 33px;
    border-radius: 999px;
    background: var(--panel-bg);
    color: var(--text-dark);
    font-size: 1.1rem;
    font-weight: 700;
    border: 1px solid var(--panel-bg);
    flex: 0 0 33px;
}
.menu-icon svg {
    display: block;
}
.menu-icon-wireframe {
    background: var(--panel-bg);
    color: var(--text-dark);
    border-color: var(--panel-bg);
}

.section-body {
    padding: 0 10px 10px 10px;
}

.wireframe-row {
    padding: 0 10px;
}

/* Nested & Toggles */
.nested-group { 
    margin-top: 10px; padding: 10px 0 10px 15px; 
    border-left: 2px solid var(--accent); background: #383838;
    border-radius: 0 8px 8px 0;
}
.toggle-group { 
    display: flex; justify-content: space-between; align-items: center; 
    margin: 15px 0; cursor: pointer;
}
.toggle-group label { font-size: 0.9rem; font-weight: 600; }
.sub-toggle { margin-top: 10px; border-top: 1px solid #eee; padding-top: 15px; }
.sub-toggle { border-top-color: #4a4a4a; }

hr { border: 0; border-top: 1px solid var(--border); margin: 20px 0; }

/* Buttons */
.btn-primary {
    width: 100%; padding: 14px; background: var(--accent-active);
    color: var(--text-dark); border: none; border-radius: 10px;
    font-weight: 700; font-size: 0.95rem; cursor: pointer;
    margin-top: 10px; transition: all 0.2s ease;
    box-shadow: none;
}
.btn-primary:hover { 
    background: var(--accent-hover); 
    transform: none;
    box-shadow: none;
}
.btn-primary:active { transform: none; }

.btn-primary .menu-icon { margin-right: 8px; }

/* Collapsed sidebar */
#ui-panel.collapsed {
    width: 76px;
    padding: 16px 10px;
}
#ui-panel.collapsed h2,
#ui-panel.collapsed .label-text,
#ui-panel.collapsed .section-body,
#ui-panel.collapsed .menu-section > summary::after,
#ui-panel.collapsed .btn-primary .label-text {
    display: none;
}
#ui-panel.collapsed .menu-section > summary {
    justify-content: center;
    padding: 8px;
}
#ui-panel.collapsed .menu-section {
    margin-bottom: 8px;
}
#ui-panel.collapsed .btn-primary {
    padding: 10px 0;
}
#ui-panel.collapsed .btn-primary .menu-icon {
    margin: 0;
}
#ui-panel.collapsed .wireframe-row input[type="checkbox"],
#ui-panel.collapsed #bboxToggle {
    display: none;
}

@media (max-width: 768px) {
    #ui-panel:not(.expanded) {
        width: 76px;
        padding: 16px 10px;
    }
    #ui-panel:not(.expanded) h2,
    #ui-panel:not(.expanded) .label-text,
    #ui-panel:not(.expanded) .section-body,
    #ui-panel:not(.expanded) .menu-section > summary::after,
    #ui-panel:not(.expanded) .btn-primary .label-text {
        display: none;
    }
    #ui-panel:not(.expanded) .menu-section > summary {
        justify-content: center;
        padding: 8px;
    }
    #ui-panel:not(.expanded) .btn-primary {
        padding: 10px 0;
    }
    #ui-panel:not(.expanded) .btn-primary .menu-icon {
        margin: 0;
    }
    #ui-panel:not(.expanded) .wireframe-row input[type="checkbox"],
    #ui-panel:not(.expanded) #bboxToggle {
        display: none;
    }
}

canvas { display: block; position: fixed; top: 0; left: 0; z-index: 1; }

/* Static pages (Methodology + Contact) */
body.static-page {
    min-height: 100vh;
    overflow-y: auto;
}

body.static-page nav {
    position: fixed;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
}

.content-wrapper {
    max-width: 980px;
    margin: 0 auto;
    padding: 110px 20px 36px;
}

.content-card {
    background: var(--panel-bg);
    border: 1px solid var(--border);
    border-radius: 16px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.25);
    padding: 28px;
}

.content-card h1,
.content-card h2 {
    margin: 0 0 18px;
    border-bottom: 1px solid var(--border);
    padding: 0 0 14px;
    font-size: 1.95rem;
    line-height: 1.2;
    letter-spacing: 0.01em;
    font-weight: 700;
}

.summary-callout {
    margin: 0 0 22px;
    padding: 16px 18px;
    border: 1px solid var(--accent-active);
    border-radius: 12px;
    background: #363636;
    line-height: 1.7;
}

.content-section {
    margin-top: 22px;
    padding: 16px 18px;
    border: 1px solid var(--border);
    border-radius: 12px;
    background: #343434;
}

.content-section h3 {
    margin: 0 0 12px;
    font-size: 1.2rem;
    line-height: 1.3;
    letter-spacing: 0.01em;
    color: var(--text-dark);
}

.content-section p {
    margin: 0 0 12px;
    line-height: 1.72;
    color: #ececec;
}

.content-section p:last-child {
    margin-bottom: 0;
}

.method-list {
    margin: 8px 0 0;
    padding-left: 18px;
    line-height: 1.72;
}

.method-list li + li {
    margin-top: 6px;
}

.content-section.refs ul {
    margin: 8px 0 0;
    padding-left: 18px;
    line-height: 1.65;
}

body.static-page .content-card a {
    color: var(--accent-active);
}

body.static-page .content-card a:hover {
    color: var(--accent-hover);
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 12px;
    margin-top: 12px;
}

.contact-item {
    background: #363636;
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 12px;
}

.contact-item strong {
    display: block;
    margin-bottom: 4px;
}

.contact-item p {
    margin: 0;
    line-height: 1.55;
}

.contact-note {
    margin: 16px 0 0;
    color: var(--text-muted);
    line-height: 1.72;
}

@media (max-width: 768px) {
    .content-wrapper {
        padding-top: 96px;
    }

    .content-card {
        padding: 20px;
    }
}