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

body {
    font-family: "Inter", "Segoe UI", system-ui, -apple-system, sans-serif;
    min-height: 100dvh;
    display: flex;
    flex-direction: column;
    align-items: center;
    -webkit-tap-highlight-color: transparent;
}

main {
    width: 100%;
    max-width: 480px;
    padding: 2rem 1.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2rem;
}

h1 {
    font-family: "Yoster Island", Verdana, Tahoma, serif;
    font-size: 48px;
    text-align: center;
}

.noise-select {
    display: flex;
    gap: 0.5rem;
    width: 100%;
}

.noise-btn {
    flex: 1;
    padding: 0.75rem 0.5rem;
    border: 3px solid #251708;
    border-radius: 8px;
    background: #F2C57C;
    color: #251708;
    font-family: inherit;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.15s, transform 0.1s;
    -webkit-user-select: none;
    user-select: none;
}

.noise-btn:active {
    transform: scale(0.97);
}

.noise-btn[data-type="pink"] { background: #F0B0A8; }
.noise-btn[data-type="brown"] { background: #D4A373; }
.noise-btn[data-type="red"] { background: #E8998D; }

.noise-btn[data-type="pink"].active { background: #EF6F6C; color: #251708; }
.noise-btn[data-type="brown"].active { background: #7F5539; color: #F2C57C; }
.noise-btn[data-type="red"].active { background: #C1121F; color: #F2C57C; }

.play-btn {
    width: 100%;
    padding: 1.25rem;
    border: 3px solid #251708;
    border-radius: 12px;
    background: #7FB685;
    color: #251708;
    font-family: inherit;
    font-size: 1.25rem;
    font-weight: 700;
    cursor: pointer;
    transition: background 0.15s, transform 0.1s;
    -webkit-user-select: none;
    user-select: none;
}

.play-btn:active {
    transform: scale(0.97);
}

.play-btn.playing {
    background: #EF6F6C;
}

.volume-group {
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.volume-group label {
    font-weight: 600;
    font-size: 0.9rem;
}

.volume-slider {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 12px;
    border-radius: 6px;
    background: #F2C57C;
    border: 2px solid #251708;
    outline: none;
}

.volume-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    background: #426A5A;
    border: 2px solid #251708;
    cursor: pointer;
}

.volume-slider::-moz-range-thumb {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    background: #426A5A;
    border: 2px solid #251708;
    cursor: pointer;
}

.back-link {
    font-size: 0.9rem;
    color: #426A5A;
    text-decoration: none;
    font-weight: 600;
}

.back-link:hover {
    text-decoration: underline;
}