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

:root {
    --primary-color: #1a1f3a;
    --secondary-color: #2d3561;
    --accent-color: #6b7fd7;
    --text-color: #e0e0e0;
    --background-color: #0f1322;
    --card-bg: #1a1f3a;
    --hover-color: #3d4570;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background-image: 
        radial-gradient(circle at 20% 80%, rgba(107, 127, 215, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(107, 127, 215, 0.05) 0%, transparent 50%);
}

.container {
    width: 100%;
    max-width: 1200px;
    padding: 20px;
}

header {
    text-align: center;
    margin-bottom: 40px;
}

h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    background: linear-gradient(135deg, #6b7fd7, #8b9dc9);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.icon {
    font-size: 3rem;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.subtitle {
    font-size: 1.1rem;
    opacity: 0.8;
}

.sound-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
}

.sound-card {
    background: var(--card-bg);
    border-radius: 15px;
    padding: 25px;
    text-align: center;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.sound-card.active {
    border-color: var(--accent-color);
    background: var(--hover-color);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(107, 127, 215, 0.3);
}

.sound-icon {
    font-size: 3rem;
    margin-bottom: 10px;
}

.sound-card h3 {
    margin-bottom: 15px;
    font-size: 1.2rem;
}

.volume-slider {
    width: 100%;
    height: 6px;
    background: var(--secondary-color);
    border-radius: 3px;
    outline: none;
    margin-bottom: 10px;
    -webkit-appearance: none;
}

.volume-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 16px;
    height: 16px;
    background: var(--accent-color);
    border-radius: 50%;
    cursor: pointer;
    transition: all 0.2s ease;
}

.volume-slider::-webkit-slider-thumb:hover {
    transform: scale(1.2);
    box-shadow: 0 0 10px rgba(107, 127, 215, 0.5);
}

.volume-value {
    font-size: 0.9rem;
    opacity: 0.8;
}

.controls {
    background: var(--card-bg);
    border-radius: 20px;
    padding: 30px;
    display: flex;
    justify-content: space-around;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.control-group {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
}

.control-group label {
    font-size: 1rem;
    opacity: 0.9;
}

#master-volume {
    width: 150px;
}

#timer {
    padding: 8px 15px;
    background: var(--secondary-color);
    color: var(--text-color);
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
}

.timer-display {
    font-size: 1.2rem;
    font-weight: bold;
    color: var(--accent-color);
}

.preset-btn {
    padding: 10px 25px;
    background: var(--secondary-color);
    color: var(--text-color);
    border: none;
    border-radius: 10px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
}

.preset-btn:hover {
    background: var(--hover-color);
    transform: translateY(-2px);
}

.preset-menu {
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    background: var(--card-bg);
    border-radius: 10px;
    padding: 10px;
    display: none;
    flex-direction: column;
    gap: 5px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.3);
    z-index: 10;
    min-width: 150px;
}

.preset-menu.show {
    display: flex;
}

.preset-menu button {
    padding: 8px 15px;
    background: var(--secondary-color);
    color: var(--text-color);
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.preset-menu button:hover {
    background: var(--hover-color);
}

.play-pause-btn {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--accent-color), #8b9dc9);
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    transition: all 0.3s ease;
    box-shadow: 0 5px 20px rgba(107, 127, 215, 0.3);
}

.play-pause-btn:hover {
    transform: scale(1.1);
    box-shadow: 0 8px 30px rgba(107, 127, 215, 0.5);
}

.play-pause-btn:active {
    transform: scale(0.95);
}

footer {
    margin-top: 40px;
    text-align: center;
    opacity: 0.7;
}

.language-selector {
    margin-bottom: 10px;
}

#language-select {
    padding: 5px 15px;
    background: var(--secondary-color);
    color: var(--text-color);
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

@media (max-width: 768px) {
    h1 {
        font-size: 2rem;
    }
    
    .sound-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
        gap: 15px;
    }
    
    .controls {
        flex-direction: column;
        gap: 25px;
    }
    
    .play-pause-btn {
        width: 70px;
        height: 70px;
    }
}