/* 2. PREMIUM APP LAYOUT (The Squeeze & Soften) */
body {
    background-color: #e2e8f0; /* Darker, distinct slate-grey background */
    margin: 0;
    padding: 0;
    color: #334155;
    font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

.app-container {
    max-width: 650px; 
    margin: 40px auto; 
    background-color: #ffffff; /* Pure white card */
    border-radius: 12px;
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.15); /* Tripled the shadow opacity so it actually pops */
    padding: 40px 30px; /* Added slightly more vertical padding */
}

/* 3. Elevate the Input Fields */
input[type="text"],
input[type="number"],
.dash-dropdown {
    width: 100%;
    padding: 12px 15px;
    margin: 8px 0 20px 0;
    border: 1px solid #cbd5e1;
    border-radius: 8px;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.02);
    transition: border-color 0.2s, box-shadow 0.2s;
}

input[type="text"]:focus,
input[type="number"]:focus {
    border-color: #3b82f6;
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
    outline: none;
}

/* 4. Action Buttons */
.action-btn-large {
    background-color: #10b981;
    color: white;
    border: none;
    padding: 15px 20px;
    font-size: 1.1em;
    font-weight: bold;
    border-radius: 8px;
    cursor: pointer;
    width: 100%;
    transition: background-color 0.2s, transform 0.1s;
}

.action-btn-large:hover {
    background-color: #059669;
    transform: translateY(-1px);
}