:root {
    --bg-dark: hsl(222, 47%, 6%);
    --bg-card: hsla(217, 33%, 12%, 0.7);
    --bg-card-hover: hsla(217, 33%, 15%, 0.8);
    --border-color: hsla(217, 30%, 20%, 0.6);
    --border-color-glow: hsla(199, 89%, 48%, 0.35);
    
    --text-primary: hsl(210, 40%, 98%);
    --text-secondary: hsl(215, 20%, 65%);
    --text-muted: hsl(215, 16%, 45%);
    
    --accent: hsl(199, 89%, 48%);
    --accent-glow: hsla(199, 89%, 48%, 0.4);
    
    --success: hsl(142, 72%, 40%);
    --success-bg: hsla(142, 72%, 40%, 0.15);
    --success-glow: hsla(142, 72%, 40%, 0.3);
    
    --warning: hsl(38, 92%, 50%);
    --warning-bg: hsla(38, 92%, 50%, 0.15);
    --warning-glow: hsla(38, 92%, 50%, 0.3);
    
    --danger: hsl(350, 89%, 55%);
    --danger-bg: hsla(350, 89%, 55%, 0.15);
    --danger-glow: hsla(350, 89%, 55%, 0.3);

    --font-family: 'Outfit', sans-serif;
}

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

body {
    background-color: var(--bg-dark);
    background-image: 
        radial-gradient(at 0% 0%, hsla(217, 100%, 15%, 0.15) 0px, transparent 50%),
        radial-gradient(at 100% 100%, hsla(199, 89%, 15%, 0.1) 0px, transparent 50%);
    color: var(--text-primary);
    font-family: var(--font-family);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 2rem 1.5rem;
}

.container {
    width: 100%;
    max-width: 1200px;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

header {
    text-align: left;
    margin-bottom: 0.5rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 1rem;
}

header h1 {
    font-weight: 600;
    font-size: 2.2rem;
    letter-spacing: -0.02em;
    background: linear-gradient(135deg, hsl(0, 0%, 100%) 30%, var(--text-secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 0.25rem;
}

header p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    font-weight: 300;
}

main {
    display: grid;
    grid-template-columns: 1.8fr 1fr;
    gap: 1.5rem;
    align-items: start;
}

@media (max-width: 950px) {
    main {
        grid-template-columns: 1fr;
    }
}

/* Simulation view containing canvas, positioning, and diagnostics */
.simulation-view {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

.canvas-wrapper {
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 0.75rem;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
    position: relative;
    aspect-ratio: 16 / 9;
    overflow: hidden;
    transition: border-color 0.3s ease;
}

.canvas-wrapper:hover {
    border-color: hsla(217, 30%, 30%, 0.8);
}

canvas {
    width: 100%;
    height: 100%;
    display: block;
    border-radius: 10px;
    background: #080c14;
}

/* Status overlay badge */
.status-overlay {
    z-index: 10;
    display: flex;
    justify-content: flex-start;
}

.status-badge {
    display: inline-block;
    padding: 0.5rem 1rem;
    border-radius: 9999px;
    font-weight: 600;
    font-size: 0.85rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    backdrop-filter: blur(12px);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    border: 1px solid transparent;
    transition: all 0.3s ease;
}

.status-badge.status-safe {
    background: var(--success-bg);
    color: var(--success);
    border-color: var(--success);
    box-shadow: 0 0 15px var(--success-glow);
}

.status-badge.status-warning {
    background: var(--warning-bg);
    color: var(--warning);
    border-color: var(--warning);
    box-shadow: 0 0 15px var(--warning-glow);
}

.status-badge.status-danger {
    background: var(--danger-bg);
    color: var(--danger);
    border-color: var(--danger);
    box-shadow: 0 0 15px var(--danger-glow);
}

/* Simulation Controls Panel */
.sim-controls-panel {
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 1.25rem;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.control-row {
    display: flex;
    gap: 0.75rem;
}

.action-btn {
    font-family: var(--font-family);
    padding: 0.6rem 1.2rem;
    border-radius: 8px;
    font-weight: 500;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.2s ease;
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.play-btn {
    background: var(--accent);
    color: var(--bg-dark);
    border-color: var(--accent);
    font-weight: 600;
    min-width: 150px;
}

.play-btn:hover {
    background: hsl(199, 95%, 55%);
    box-shadow: 0 0 12px var(--accent-glow);
}

.play-btn.playing {
    background: var(--warning);
    border-color: var(--warning);
}

.play-btn.playing:hover {
    background: hsl(38, 95%, 55%);
    box-shadow: 0 0 12px var(--warning-glow);
}

.reset-btn {
    background: transparent;
    color: var(--text-primary);
}

.reset-btn:hover {
    background: rgba(255, 255, 255, 0.05);
    border-color: var(--text-secondary);
}

.slider-container {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}

.slider-container label {
    font-size: 0.85rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

.slider-wrapper {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.slider-wrapper input[type="range"] {
    flex: 1;
}

/* Diagnostics Grid */
.diagnostics-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.25rem;
}

@media (max-width: 600px) {
    .diagnostics-grid {
        grid-template-columns: 1fr;
    }
}

.diagnostic-card {
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 1.25rem;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    transition: all 0.3s ease;
}

.diagnostic-card.card-safe {
    border-color: hsla(142, 72%, 40%, 0.3);
}

.diagnostic-card.card-danger {
    border-color: hsla(350, 89%, 55%, 0.3);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.5rem;
}

.card-title {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.card-indicator {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
}

.card-indicator.safe {
    background: var(--success-bg);
    color: var(--success);
}

.card-indicator.danger {
    background: var(--danger-bg);
    color: var(--danger);
}

.metric-row {
    display: flex;
    justify-content: space-between;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.metric-value {
    color: var(--text-primary);
    font-weight: 500;
    font-family: monospace;
}

.footer-metric {
    border-top: 1px dashed var(--border-color);
    padding-top: 0.5rem;
    margin-top: 0.25rem;
    font-weight: 600;
}

.footer-metric .metric-label {
    color: var(--text-primary);
}

.font-highlight {
    font-size: 1.1rem;
}

.font-highlight.safe {
    color: var(--success);
}

.font-highlight.danger {
    color: var(--danger);
}

/* Sidebar controls styling */
.controls {
    background: var(--bg-card);
    backdrop-filter: blur(16px);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 1.5rem;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

.panel-section-title {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 0.2rem;
    border-left: 2px solid var(--accent);
    padding-left: 0.5rem;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}

.control-group label {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* Custom Range Input */
input[type="range"] {
    -webkit-appearance: none;
    width: 100%;
    height: 6px;
    background: var(--border-color);
    border-radius: 3px;
    outline: none;
    transition: background 0.3s;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 16px;
    height: 16px;
    background: var(--accent);
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 0 8px var(--accent-glow);
    transition: transform 0.1s, background-color 0.1s;
    border: 2px solid var(--bg-dark);
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.25);
    background: #fff;
}

.control-group .readout {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-primary);
    text-align: right;
    font-family: monospace;
    margin-top: -0.1rem;
}

/* Preset buttons layout - 3x2 grid */
.preset-buttons {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0.5rem;
}

.preset-btn {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    padding: 0.5rem 0.25rem;
    border-radius: 8px;
    cursor: pointer;
    font-family: var(--font-family);
    font-size: 0.8rem;
    font-weight: 400;
    text-align: center;
    transition: all 0.2s ease;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.preset-btn:hover {
    border-color: var(--accent);
    color: var(--accent);
    background: rgba(56, 189, 248, 0.05);
}

.preset-btn.active {
    background: var(--accent);
    color: var(--bg-dark);
    border-color: var(--accent);
    font-weight: 600;
    box-shadow: 0 0 10px var(--accent-glow);
}

/* Checkbox and File Inputs for Image Overlay */
.check-group {
    display: flex;
    align-items: center;
    margin-top: 0.25rem;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    user-select: none;
}

.checkbox-label input[type="checkbox"] {
    appearance: none;
    -webkit-appearance: none;
    width: 16px;
    height: 16px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background: rgba(255, 255, 255, 0.03);
    outline: none;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
}

.checkbox-label input[type="checkbox"]:checked {
    background: var(--accent);
    border-color: var(--accent);
    box-shadow: 0 0 8px var(--accent-glow);
}

.checkbox-label input[type="checkbox"]:checked::before {
    content: "✓";
    font-size: 0.7rem;
    color: var(--bg-dark);
    font-weight: bold;
}

.file-label {
    display: block;
    margin-bottom: 0.4rem;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.file-input {
    display: block;
    width: 100%;
    font-family: var(--font-family);
    font-size: 0.8rem;
    color: var(--text-secondary);
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 0.4rem 0.6rem;
    outline: none;
    cursor: pointer;
    transition: all 0.2s ease;
}

.file-input::file-selector-button {
    background: var(--border-color);
    border: none;
    color: var(--text-primary);
    padding: 0.25rem 0.6rem;
    border-radius: 4px;
    cursor: pointer;
    margin-right: 0.5rem;
    font-family: var(--font-family);
    font-size: 0.75rem;
    font-weight: 600;
    transition: background 0.2s ease;
}

.file-input::file-selector-button:hover {
    background: var(--accent);
    color: var(--bg-dark);
}