body {
    margin: 0;
    font-family: 'Segoe UI', sans-serif;
    background: linear-gradient(135deg, #e34bb1, #e3cf30);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    
}

h1 {
    margin: 30px 0;
    color: white;
    text-shadow: 0 3px 10px rgba(0,0,0,0.2);
}

.calendar {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
    gap: 20px;
    width: 90%;
    max-width: 900px;
    padding-bottom: 40px;
}

.door {
    perspective: 1200px;
}

.inner {
    position: relative;
    width: 100%;
    height: 140px;
    transform-style: preserve-3d;
    transition: transform 0.8s cubic-bezier(.4,2,.3,1);
}

.door.open .inner {
    transform: rotateY(180deg);
}

.front, .back {
    position: absolute;
    width: 100%;
    height: 100%;
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    backface-visibility: hidden;
    box-shadow: 0 10px 25px rgba(0,0,0,0.2);
}

/* Etupuoli */
.front {
    background: rgba(255,255,255,0.25);
    backdrop-filter: blur(10px);
    color: white;
    font-size: 22px;
    font-weight: bold;
    transition: 0.3s;
}

/* Hover efekti */
.door:not(.locked):hover .front {
    transform: scale(1.0) rotate(-1deg);
    box-shadow: 0 15px 30px rgba(0,0,0,0.3);
}

/* Takapuoli */
.back {
    background: linear-gradient(135deg, #ffeaa7, #fab1a0);
    transform: rotateY(180deg);
    text-align: center;
    font-size: 15px;
    color: #2d3436;
}

/* Lukittu */
.locked .front {
    background: rgba(200,200,200,0.4);
    color: #666;
    cursor: not-allowed;
}

.locked::after {
    content: "🔒";
    position: absolute;
    top: 10px;
    right: 12px;
    font-size: 18px;
}