:root {
    --bg-dark: #121212;
    --bg-sidebar: #1e1e1e;
    --accent: #007AFF;
    --accent-hover: #0056b3;
    --text-main: #e0e0e0;
    --text-secondary: #a0a0a0;
    --danger: #ff453a;
    --success: #32d74b;
    --border: #333;
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

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

body {
    background-color: var(--bg-dark);
    color: var(--text-main);
    font-family: var(--font-family);
    overflow: hidden;
    height: 100vh;
}

#app {
    display: flex;
    height: 100%;
}

/* Sidebar Styling */
#sidebar {
    width: 320px;
    background-color: var(--bg-sidebar);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    padding: 1.5rem;
    overflow-y: auto;
}

header {
    margin-bottom: 2rem;
}

h1 {
    font-size: 1.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, #fff, var(--text-secondary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.subtitle {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-top: 0.2rem;
}

.control-group {
    margin-bottom: 1.5rem;
}

label {
    display: block;
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

select,
input[type="range"] {
    width: 100%;
    margin-bottom: 0.5rem;
}

select {
    background-color: #2c2c2e;
    border: 1px solid var(--border);
    color: var(--text-main);
    padding: 0.6rem;
    border-radius: 8px;
    font-size: 0.9rem;
    outline: none;
    transition: border-color 0.2s;
}

select:focus {
    border-color: var(--accent);
}

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

.slider-container span {
    font-size: 0.9rem;
    min-width: 45px;
    text-align: right;
    color: var(--text-main);
}

#results {
    background-color: #2c2c2e;
    padding: 1.2rem;
    border-radius: 12px;
    margin-top: auto;
}

#results h3 {
    font-size: 1rem;
    margin-bottom: 1rem;
    border-bottom: 1px solid var(--border);
    padding-bottom: 0.5rem;
}

.stat {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
}

.stat .label {
    color: var(--text-secondary);
}

.stat .value {
    font-weight: 600;
    color: var(--accent);
}

.stat.separator {
    height: 1px;
    background: var(--border);
    margin: 0.8rem 0;
}

.primary-btn {
    width: 100%;
    background-color: var(--accent);
    color: white;
    border: none;
    padding: 0.8rem;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    margin-top: 1.5rem;
    transition: background-color 0.2s;
}

.primary-btn:hover {
    background-color: var(--accent-hover);
}

/* Viewport Styling */
#viewport {
    flex: 1;
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 2rem;
    background: radial-gradient(circle at center, #1a1a1a 0%, #000 100%);
}

#canvas-container {
    position: relative;
    width: 100%;
    max-height: 100%;
    aspect-ratio: 2 / 1;
}

#equirect-gl,
#equirect-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: 1px solid var(--border);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

#equirect-gl {
    background-color: #000;
}

#equirect-overlay {
    background: transparent;
    pointer-events: auto;
}

#tooltip {
    position: fixed;
    background: rgba(0, 0, 0, 0.85);
    color: var(--text-main);
    padding: 0.4rem 0.7rem;
    border-radius: 6px;
    font-size: 0.8rem;
    pointer-events: none;
    z-index: 100;
    white-space: nowrap;
}

#tooltip.hidden {
    display: none;
}

#canvas-labels {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    padding: 2rem;
}

.axis-label {
    position: absolute;
    font-size: 0.7rem;
    text-transform: uppercase;
    color: var(--text-secondary);
    letter-spacing: 0.1em;
}

.axis-label.lat {
    top: 50%;
    left: 0.5rem;
    transform: rotate(-90deg) translateX(50%);
}

.axis-label.lon {
    bottom: 1.5rem;
    left: 50%;
    transform: translateX(-50%);
}

.legend {
    position: absolute;
    top: 1rem;
    right: 1rem;
    display: flex;
    gap: 1rem;
    background: rgba(0, 0, 0, 0.6);
    padding: 0.5rem 0.8rem;
    border-radius: 4px;
    backdrop-filter: blur(4px);
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.75rem;
}

.box {
    width: 12px;
    height: 12px;
    border-radius: 2px;
}

.box.covered {
    background: rgba(0, 122, 255, 0.4);
    border: 1px solid var(--accent);
}

.box.gap {
    background: rgba(255, 69, 58, 0.2);
    border: 1px solid var(--danger);
}

footer {
    margin-top: 1rem;
    text-align: center;
    font-size: 0.7rem;
    color: var(--text-secondary);
    opacity: 0.6;
}

/* Custom Range Input */
input[type=range] {
    -webkit-appearance: none;
    appearance: none;
    background: transparent;
}

input[type=range]::-webkit-slider-runnable-track {
    width: 100%;
    height: 4px;
    background: var(--border);
    border-radius: 2px;
}

input[type=range]::-webkit-slider-thumb {
    -webkit-appearance: none;
    height: 16px;
    width: 16px;
    border-radius: 50%;
    background: var(--accent);
    margin-top: -6px;
    cursor: pointer;
    box-shadow: 0 0 5px rgba(0, 0, 0, 0.3);
}