/* CSS Variable System */
:root {
    --bg-dark: #0a0c10;
    --panel-bg: rgba(22, 28, 38, 0.75);
    --border-color: rgba(255, 255, 255, 0.08);
    --primary-color: #d4a574;
    --primary-hover: #b88d5e;
    --text-color: #e2e8f0;
    --text-muted: #8a99ad;
    --font-sans: 'Inter', sans-serif;
    --font-mono: 'Fira Code', monospace;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

/* Layout App Container */
.app-container {
    display: flex;
    height: 100vh;
    width: 100vw;
}

/* Sidebar Control Panel */
.control-panel {
    width: 360px;
    background-color: var(--panel-bg);
    border-right: 1px solid var(--border-color);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    display: flex;
    flex-direction: column;
    padding: 2rem 1.5rem;
    gap: 1.5rem;
    overflow-y: auto;
    z-index: 10;
}

/* Header design */
.app-header .badge {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    background-color: rgba(212, 165, 116, 0.15);
    color: var(--primary-color);
    font-size: 0.75rem;
    font-weight: bold;
    padding: 0.25rem 0.6rem;
    border-radius: 9999px;
    margin-bottom: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.app-header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 0.25rem;
}

.app-header p {
    font-size: 0.85rem;
    color: var(--text-muted);
    line-height: 1.4;
}

/* Control Elements */
.control-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

label {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    display: flex;
    align-items: center;
    gap: 0.35rem;
}

.form-select {
    width: 100%;
    padding: 0.6rem;
    background-color: rgba(0, 0, 0, 0.3);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    font-size: 0.9rem;
    border-radius: 6px;
    outline: none;
    cursor: pointer;
    transition: var(--transition);
    height: 2.5rem;
}

.form-select:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(212, 165, 116, 0.2);
}

/* Sliders */
.slider-item {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
}

.slider-header {
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-muted);
}

.slider-val {
    color: var(--primary-color);
    font-family: var(--font-mono);
}

input[type="range"] {
    -webkit-appearance: none;
    width: 100%;
    height: 4px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 2px;
    outline: none;
    cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--primary-color);
    transition: var(--transition);
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.3);
    background: #fff;
}

/* Buttons */
.btn {
    flex: 1;
    padding: 0.6rem;
    font-size: 0.85rem;
    font-weight: 600;
    border-radius: 6px;
    border: 1px solid var(--border-color);
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.35rem;
    transition: var(--transition);
}

.btn-primary {
    background-color: var(--primary-color);
    color: #1a1a24;
    border-color: var(--primary-color);
}

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

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

.btn-secondary:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

/* Stopwatch Panel */
.stopwatch-panel {
    border: 1px solid var(--border-color);
    padding: 1rem;
    border-radius: 8px;
    background-color: rgba(0, 0, 0, 0.2);
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.stopwatch-panel h3 {
    font-size: 0.8rem;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--primary-color);
}

.stopwatch-readout {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    text-align: center;
    color: var(--text-color);
    letter-spacing: 0.05em;
    padding: 0.4rem;
    background-color: rgba(0, 0, 0, 0.3);
    border: 1px solid var(--border-color);
    border-radius: 4px;
}

.stopwatch-buttons {
    display: flex;
    gap: 0.5rem;
}

/* Mathematical Information Board */
.math-board {
    margin-top: auto;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: rgba(0, 0, 0, 0.2);
    overflow: hidden;
}

.board-header {
    background-color: rgba(255, 255, 255, 0.02);
    padding: 0.5rem 0.75rem;
    border-bottom: 1px solid var(--border-color);
}

.board-header h4 {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: 0.35rem;
}

.board-content {
    padding: 0.75rem;
    font-size: 0.8rem;
    line-height: 1.5;
}

.board-content code {
    display: block;
    font-family: var(--font-mono);
    color: #a0aec0;
    margin-bottom: 0.25rem;
    background: rgba(0, 0, 0, 0.4);
    padding: 0.15rem 0.35rem;
    border-radius: 4px;
    font-size: 0.75rem;
}

.board-content p {
    color: var(--text-muted);
    margin-top: 0.5rem;
    font-size: 0.75rem;
}

/* Canvas Container */
.canvas-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    position: relative;
    background-color: var(--bg-dark);
}

#p5-canvas-holder {
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    border-radius: 12px;
    overflow: hidden;
    border: 1px solid var(--border-color);
    line-height: 0;
}

/* Canvas HUD Overlay */
.canvas-hud {
    position: absolute;
    bottom: 2rem;
    left: 2rem;
    right: 2rem;
    display: flex;
    justify-content: space-between;
    font-size: 0.75rem;
    color: var(--text-muted);
    background-color: rgba(10, 12, 16, 0.85);
    border: 1px solid var(--border-color);
    padding: 0.6rem 1.2rem;
    border-radius: 30px;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

#canvasStats {
    font-family: var(--font-mono);
}

/* Scrollbar Customization for sidebar */
.control-panel::-webkit-scrollbar {
    width: 6px;
}

.control-panel::-webkit-scrollbar-track {
    background: transparent;
}

.control-panel::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 3px;
}

.control-panel::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.2);
}