:root {
    --bg-dark: #0a0a0c;
    --bg-light: #f8f9fa;
    --bg-gradient: radial-gradient(circle at center, #1a1a2e 0%, #0a0a0c 100%);
    --accent: #00d2ff;
    --accent-glow: rgba(0, 210, 255, 0.4);
    --text-dark: #ffffff;
    --text-light: #2d3436;
    --panel-bg: rgba(255, 255, 255, 0.05);
    --panel-border: rgba(255, 255, 255, 0.1);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: 'Outfit', 'Inter', sans-serif;
    overflow: hidden;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: var(--bg-dark);
    color: var(--text-dark);
    transition: var(--transition);
}

body.theme-light {
    background-color: var(--bg-light);
    color: var(--text-light);
}

body.theme-gradient {
    background: var(--bg-gradient);
}

#app {
    width: 100%;
    height: 100vh;
    display: grid;
    grid-template-areas: 
        "header"
        "canvas"
        "controls"
        "footer";
    grid-template-rows: auto 1fr auto auto;
    gap: 1rem;
    padding: 2rem;
}

header {
    grid-area: header;
    text-align: center;
    z-index: 10;
}

h1 {
    font-size: 2.5rem;
    font-weight: 600;
    letter-spacing: 0.1rem;
    background: linear-gradient(135deg, #00d2ff 0%, #3a7bd5 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 0.5rem;
}

.subtitle {
    font-size: 0.9rem;
    opacity: 0.6;
    letter-spacing: 0.05rem;
}

main {
    grid-area: canvas;
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
    cursor: crosshair;
}

.canvas-container {
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    filter: drop-shadow(0 0 30px rgba(0, 0, 0, 0.5));
}

canvas {
    background: transparent;
    max-width: 100%;
    max-height: 100%;
    border-radius: 50%;
    box-shadow: 0 0 0 1px var(--panel-border);
}

.controls {
    grid-area: controls;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 3rem;
    padding: 1.5rem 2rem;
    background: var(--panel-bg);
    backdrop-filter: blur(20px);
    border: 1px solid var(--panel-border);
    border-radius: 100px;
    margin: 0 auto;
    z-index: 20;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.control-group label {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.1rem;
    opacity: 0.5;
    text-align: center;
}

.button-row {
    display: flex;
    gap: 0.5rem;
}

button {
    cursor: pointer;
    border: none;
    outline: none;
    font-family: inherit;
    transition: var(--transition);
}

.toggle-btn, .theme-btn {
    width: 3rem;
    height: 2.2rem;
    border-radius: 1.1rem;
    background: rgba(255, 255, 255, 0.05);
    color: inherit;
    font-size: 0.8rem;
    border: 1px solid transparent;
}

.toggle-btn.active, .theme-btn.active {
    background: var(--accent);
    color: #fff;
    box-shadow: 0 4px 15px var(--accent-glow);
}

.action-buttons {
    display: flex;
    gap: 1rem;
}

.action-buttons button {
    padding: 0.8rem 1.5rem;
    border-radius: 1.5rem;
    font-size: 0.9rem;
    font-weight: 500;
}

button.primary {
    background: var(--accent);
    color: #fff;
    box-shadow: 0 4px 20px var(--accent-glow);
}

button.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px var(--accent-glow);
}

button.secondary {
    background: rgba(255, 255, 255, 0.1);
    color: inherit;
}

button.secondary:hover {
    background: rgba(255, 255, 255, 0.2);
}

footer {
    grid-area: footer;
    text-align: center;
    padding: 1rem;
    font-size: 0.8rem;
    opacity: 0.4;
}

/* Mobile responsive */
@media (max-width: 768px) {
    .controls {
        flex-direction: column;
        border-radius: 20px;
        gap: 1.5rem;
        width: 100%;
    }
    
    #app {
        padding: 1rem;
    }
}