:root {
    --bg-color: #0A0A0A;
    --text-primary: #E0E0E0;
    --text-secondary: #A0A0A0;
    --accent-color: #00FFAB;
    --border-color: #333333;
    --font-sans: 'Inter', sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    font-family: var(--font-sans);
    height: 100vh;
    overflow: hidden;
    /* App-like feel */
    display: flex;
    flex-direction: column;
}

#app {
    display: flex;
    flex-direction: column;
    height: 100%;
    width: 100%;
}

/* Site Header */
.site-header {
    padding: 1rem 2rem;
    border-bottom: 1px solid var(--border-color);
    flex-shrink: 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header-left {
    display: flex;
    align-items: baseline;
    gap: 1rem;
}

.site-title {
    font-family: var(--font-mono);
    font-weight: 700;
    font-size: 1.1rem;
    letter-spacing: -0.5px;
    color: var(--text-primary);
    cursor: pointer;
}

.site-title:hover {
    color: var(--accent-color);
}

.site-subtitle {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--text-secondary);
    /* text-transform: uppercase; Removed as per request "written regularly" */
    letter-spacing: 1px;
}

.back-link {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-secondary);
    text-decoration: none;
    border: 1px solid var(--border-color);
    padding: 0.5rem 1rem;
    transition: all 0.2s ease;
}

.back-link:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

/* Views */
.view-section {
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.hidden {
    display: none !important;
}

/* Home View */
#home-view {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 100%;
    padding-bottom: 20vh;
    /* Visual optical center */
}

.search-container {
    width: 100%;
    max-width: 600px;
    position: relative;
    margin-bottom: 1rem;
}

#concept-search {
    width: 100%;
    background: transparent;
    border: none;
    border-bottom: 2px solid var(--text-secondary);
    color: var(--text-primary);
    font-family: var(--font-mono);
    font-size: 1.5rem;
    padding: 0.5rem 0;
    outline: none;
    text-align: center;
    transition: border-color 0.3s ease;
}

#concept-search:focus {
    border-bottom-color: var(--accent-color);
}

.start-instruction {
    font-family: var(--font-mono);
    color: var(--text-secondary);
    font-size: 0.8rem;
    opacity: 0.6;
}

.search-results {
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background: #111;
    border: 1px solid var(--border-color);
    max-height: 200px;
    overflow-y: auto;
    display: none;
    z-index: 100;
}

.search-result-item {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
    cursor: pointer;
    font-family: var(--font-mono);
    color: var(--text-secondary);
    display: flex;
    justify-content: space-between;
}

.search-result-item:hover {
    background: #1a1a1a;
    color: var(--accent-color);
}

/* Core View Layout */
.core-view {
    display: flex;
    flex: 1;
    overflow: hidden;
}

/* Sidebar */
.sidebar-exclusions {
    width: 250px;
    border-right: 1px solid var(--border-color);
    padding: 2rem;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    display: flex;
    flex-direction: column;
}

.sidebar-header {
    text-transform: uppercase;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    letter-spacing: 1px;
    font-size: 0.75rem;
}

#exclusion-list {
    list-style: none;
}

.exclusion-item {
    margin-bottom: 1rem;
    padding-left: 1rem;
    border-left: 1px solid var(--border-color);
    color: var(--text-secondary);
    transition: all 0.2s ease;
}

.exclusion-item:hover {
    border-left-color: var(--accent-color);
    color: var(--text-primary);
}

.exclusion-target {
    color: var(--accent-color);
    display: block;
    font-size: 0.75rem;
    margin-top: 0.2rem;
}

/* Center Stage */
.definition-stage {
    flex: 1;
    padding: 4rem 6rem;
    overflow-y: auto;
    max-width: 1200px;
}

/* Typography & Header */
.concept-meta {
    font-family: var(--font-mono);
    color: var(--accent-color);
    font-size: 0.8rem;
    margin-bottom: 1rem;
    display: flex;
    justify-content: space-between;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.concept-title {
    font-size: 4rem;
    font-weight: 300;
    margin-bottom: 2rem;
    letter-spacing: -1px;
}

.definition-text {
    font-size: 1.5rem;
    line-height: 1.5;
    margin-bottom: 3rem;
    font-weight: 300;
}

/* Constraints */
.constraints-container {
    margin-bottom: 3rem;
    border-top: 1px solid var(--border-color);
    padding-top: 2rem;
}

.constraints-container h3,
.comparisons-container h3,
.visual-container h3 {
    font-family: var(--font-mono);
    font-size: 0.9rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    margin-bottom: 1.5rem;
}

.constraints-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
}

.constraint-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border-color);
    padding: 1rem;
    font-family: var(--font-mono);
    font-size: 0.8rem;
}

.constraint-attr {
    color: var(--text-secondary);
    display: block;
    margin-bottom: 0.5rem;
}

.constraint-val {
    color: var(--accent-color);
    font-weight: 700;
}

.constraint-fail {
    display: block;
    margin-top: 0.5rem;
    color: #FF4A4A;
    font-size: 0.7rem;
}

/* Comparisons */
.structural-comparison {
    margin-bottom: 1.5rem;
    padding-left: 1.5rem;
    border-left: 2px solid var(--border-color);
}

.comparison-header {
    font-family: var(--font-mono);
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.comparison-text {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.4;
}

/* Visual Container */
.vector-stage {
    width: 100%;
    height: 300px;
    /* Fixed height for diagram */
    border: 1px solid var(--border-color);
    background: #0F0F0F;
    display: flex;
    justify-content: center;
    align-items: center;
}

.diagram-caption {
    font-family: var(--font-mono);
    text-align: center;
    margin-top: 0.5rem;
    color: var(--accent-color);
    font-size: 0.8rem;
}

/* Example Drawer */
.example-drawer {
    background: #0E0E0E;
    border-top: 1px solid var(--border-color);
    transition: height 0.3s ease;
    height: 50px;
    /* Collapsed height */
}

.example-drawer.open {
    height: 300px;
}

.drawer-handle {
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 2px;
}

.drawer-handle:hover {
    color: var(--accent-color);
}

.drawer-content {
    padding: 2rem;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    overflow-y: auto;
    height: calc(100% - 50px);
}

.example-card {
    border: 1px solid var(--border-color);
    padding: 1.5rem;
}

.example-title {
    font-family: var(--font-mono);
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    font-weight: bold;
}

.example-desc {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.4;
}

/* Embed Mode */
body.embed-mode .core-view,
body.embed-mode .view-section {
    height: 100vh;
}