body {
    background: linear-gradient(120deg, #181f2a 0%, #253046 100%);
    font-family: 'Segoe UI', Arial, sans-serif;
    min-height: 100vh;
    margin: 0;
    color: #fff;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}
.mainbox {
    max-width: 680px;
    margin: 3.5rem auto 1.5rem auto;
}
.card-mild {
    position: relative;
    background: rgba(28, 35, 60, 0.92);
    border-radius: 20px;
    box-shadow: 0 8px 40px 0 #1a202e44, 0 1px 14px 0 #34e3fa13 inset;
    padding: 2.3rem 2.5rem 1.5rem 2.5rem;
    text-align: center;
    overflow: hidden;
    border: 1.6px solid #37c2ff18;
    margin-bottom: 2.2rem;
}
.card-mild .headline {
    font-size: 1.24rem;
    color: #e1f2ff;
    letter-spacing: 1.4px;
    margin-bottom: 0.45rem;
    font-weight: 500;
    text-shadow: 0 1px 9px #29e2fd55;
    position: relative;
}
.card-mild h1 {
    font-size: 3.2rem;
    margin: 0 0 1.0rem 0;
    font-weight: 600;
    letter-spacing: 1px;
    text-shadow: 0 0 22px #37c2ff44, 0 2px 3px #fff3;
    line-height: 1.11;
    background: linear-gradient(90deg, #36d7ff 50%, #b5e4ff 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.card-mild .time {
    color: #88e8ff;
    font-size: 1.11rem;
    margin-bottom: 0.22rem;
    letter-spacing: 0.5px;
    font-weight: 500;
}
.chartbox-mild {
    background: rgba(24, 28, 47, 0.98);
    border-radius: 16px;
    padding: 1.7rem 1.6rem 1.2rem 1.6rem;
    margin: 0.8rem auto 2.2rem auto;
    max-width: 780px;
    min-width: 0;
    box-shadow: 0 2px 22px #29a7fa13;
    border: 1px solid #36d7ff21;
    position: relative;
}
form[method="get"] {
    margin-bottom: 1.18rem;
    text-align: center;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.35rem 1.2rem;
}
select, input[type="datetime-local"] {
    background: #1b233b;
    color: #fff;
    border: 1px solid #36d7ff90;
    padding: 0.41rem 0.75rem;
    border-radius: 8px;
    margin: 0 0.19rem;
    font-size: 1.03rem;
}
label {
    color: #84caff;
    margin-right: 0.4rem;
    font-size: 1.08rem;
    cursor: pointer;
    font-weight: 500;
}
button[type="submit"] {
    background: linear-gradient(90deg, #37c2ff 0%, #82e6ff 100%);
    color: #fff;
    border: none;
    border-radius: 8px;
    padding: 0.51rem 1.18rem;
    font-size: 1.13rem;
    font-weight: 600;
    box-shadow: 0 2px 12px #36d7ff22;
    cursor: pointer;
    margin-left: 0.45rem;
    letter-spacing: 1px;
    transition: background 0.18s;
}
button[type="submit"]:hover {
    background: linear-gradient(90deg, #2566db 0%, #48d9ff 100%);
}
#chart {
    min-height: 265px;
    max-height: 310px;
}
footer {
    text-align: center;
    color: #8ccbf2;
    font-size: 1.12rem;
    letter-spacing: 0.7px;
    padding: 1.6rem 0 1.2rem 0;
    margin-top: auto;
    opacity: 0.91;
    background: none;
    font-weight: 400;
}
footer strong {
    color: #36d7ff;
    font-weight: 700;
    letter-spacing: 1.2px;
    text-shadow: 0 0px 6px #36d7ff45;
}
@media (max-width: 900px) {
    .mainbox, .card-mild, .chartbox-mild { max-width: 99vw;}
    .card-mild h1 { font-size: 2.1rem; }
}