/* style.css - shared for all pages */

body {
    font-family: -apple-system, BlinkMacSystemFont, sans-serif;
    background: #0f172a;
    color: white;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: flex-start; /* changed from center for scrolling pages */
    /* min-height: 100vh; */
}

.container {
    text-align: center;
    width: 90%;
    max-width: 650px;
    margin: 20px auto;
}

h1, h2, h3 {
    margin: 10px 0 20px 0;
    font-weight: 600;
}

strong {
    display: inline;
}

.card {
    display: flex;
    flex-direction: column;
    gap: 15px;
    background: #1e293b;
    padding: 20px;
    border-radius: 16px;
    margin-bottom: 20px;
}

.dropdown {
    /* width: 80%; */
    padding: 10px;
    margin-bottom: 10px;
    border-radius: 8px;
    border: none;
    font-size: 16px;
}

input {
    /* width: 80%; */
    padding: 10px;
    margin-bottom: 10px;
    border-radius: 8px;
    border: none;
    font-size: 16px;
}

button {
    padding: 16px;
    font-size: 1.1rem;
    border-radius: 12px;
    border: none;
    font-weight: bold;
    color: black;
    background: #22c55e;
    cursor: pointer;
    transition: transform 0.1s ease;
}

button:active {
    transform: scale(0.97);
}

.result {
    display: block;
    font-size: 18px;
    text-align: center;
    text-align: left;
    line-height: 1.6;
    word-break: normal;
}

/* Chart.js canvas styling */
canvas {
    background: white;
    border-radius: 8px;
    max-width: 100%;
}

/* Tank visual container */
#tankContainer {
    display: flex;
    gap: 20px;
    margin-top: 10px;
    align-items: flex-end;
    justify-content: center;
}

#tank {
    position: relative;
    width: 60px;
    height: 220px;
    border: 2px solid white;
    border-radius: 10px;
    overflow: hidden;
}

.tankLayer {
    position: absolute;
    width: 100%;
}

#reserveGas { background: #ef4444; }
#rockGas    { background: #facc15; }
#bottomGas  { background: #22c55e; }

/* Responsive tweaks for small mobile screens */
@media (max-width: 400px) {
    .card {
        padding: 15px;
        gap: 12px;
    }
    input, button {
        font-size: 14px;
        padding: 12px;
    }
}