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

body {
    width: 100%;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    font-family: 'Segoe UI', system-ui, sans-serif;
    background: url('lake.webp') no-repeat center center;
    background-size: cover;
    background-attachment: fixed;
    background-color: #1a1a1a; /* fallback color in case image fails */
}

#show {
    width: 90%;
    max-width: 400px;
    padding: 2.5rem;
    text-align: center;
    color: #ffffff;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
    gap: 1.5rem;
    
    /* glass effect */
    background: rgba(0, 0, 0, 0.45);
    backdrop-filter: blur(20px); /* Chrome, Edge, Firefox compatible*/
    -webkit-backdrop-filter: blur(20px); /* Safari */
    
    border-radius: 24px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
}

h1 {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    font-weight: 600;
}

.controls {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

input[type="date"] {
    width: 100%;
    padding: 12px;
    border-radius: 12px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    background: rgba(0, 0, 0, 0.2);
    color: #ffffff;
    font-size: 1rem;
    outline: none;
}

input::-webkit-calendar-picker-indicator { /* Selects the small calendar icon inside the date input */
    filter: invert(1); /* Flips the icon color from black to white for better visibility on dark themes */
    cursor: pointer; /* Changes the mouse cursor to a hand to show it is clickable */
}

button {
    width: 100%;
    padding: 14px;
    border-radius: 12px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    background: #003542;
    color: #ffffff;
    font-weight: bold;
    font-size: 1rem;
    cursor: pointer;
    transition: 0.3s ease;
}

button:hover {
    background: #005f73;
    transform: translateY(-2px);
}

#result {
    margin-top: 1rem;
    margin-bottom: 1rem;
    min-height: auto;
}

#result h2 {
    font-size: 1.2rem;
    animation: fadeIn 0.5s ease;
}

.day-result {
    color: #ffffff;
    font-size: 2.2rem;
    font-weight: 800;
    text-shadow: 
        0 0 10px rgba(0, 0, 0, 0.8), 
        0 0 20px rgba(0, 0, 0, 0.4);
}

.footer-note {
    font-size: 0.75rem;
    opacity: 0.6;
    margin-top: 0.5rem;
    line-height: 1.2;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}