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

body {
    font-family: 'Arial', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    user-select: none;
}

.container {
    max-width: 500px;
    margin: 0 auto;
    text-align: center;
}

h1 {
    color: white;
    margin-bottom: 30px;
    font-size: 2.5rem;
    text-shadow: 0 2px 10px rgba(0,0,0,0.3);
}

.pad-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    padding: 20px;
}

.pad-button {
    position: relative;
    width: 100%;
    height: 100px;
    border: none;
    border-radius: 15px;
    background: linear-gradient(145deg, #f0f0f3, #cacaca);
    box-shadow: 
        20px 20px 60px #bebebe,
        -20px -20px 60px #ffffff;
    cursor: pointer;
    transition: all 0.3s ease;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.pad-button:active {
    transform: scale(0.95);
    box-shadow: 
        inset 20px 20px 60px #bebebe,
        inset -20px -20px 60px #ffffff;
}

.note-text {
    font-size: 1.8rem;
    font-weight: bold;
    color: #333;
    z-index: 2;
    position: relative;
    text-shadow: 0 1px 3px rgba(0,0,0,0.3);
}

.glow-border {
    position: absolute;
    top: -2px;
    left: -2px;
    right: -2px;
    bottom: -2px;
    border-radius: 17px;
    background: linear-gradient(45deg, 
        #ff6b6b, #4ecdc4, #45b7d1, #96ceb4, 
        #feca57, #ff9ff3, #54a0ff, #5f27cd);
    background-size: 400% 400%;
    opacity: 0;
    z-index: 1;
    animation: glowRotate 2s linear infinite;
}

.pad-button.active .glow-border {
    opacity: 1;
}

.pad-button.active {
    background: linear-gradient(145deg, #667eea, #764ba2);
    color: white;
    box-shadow: 
        0 0 30px rgba(102, 126, 234, 0.6),
        inset 5px 5px 15px rgba(255,255,255,0.1),
        inset -5px -5px 15px rgba(0,0,0,0.1);
}

.pad-button.active .note-text {
    color: white;
    text-shadow: 0 0 10px rgba(255,255,255,0.8);
}

@keyframes glowRotate {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

/* Responsivo */
@media (max-width: 480px) {
    .pad-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 15px;
        padding: 15px;
    }
    
    .pad-button {
        height: 80px;
    }
    
    .note-text {
        font-size: 1.5rem;
    }
    
    h1 {
        font-size: 2rem;
    }
}

@media (max-width: 320px) {
    .pad-grid {
        grid-template-columns: 1fr;
    }
}

/* PWA - Remover seleção de texto */
* {
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -khtml-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

/* PWA - Melhorar touch */
.pad-button {
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
}