:root {
    --bg: #f4f7fb;
    --card: #ffffff;
    --text: #1b2634;
    --border: #d2dae6;
    --brand: #0f5fa8;
    --strong: rgba(34, 163, 74, 0.6);
    --medium: rgba(240, 196, 33, 0.65);
    --weak: rgba(209, 52, 52, 0.65);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: "Segoe UI", Tahoma, sans-serif;
    color: var(--text);
    background: linear-gradient(180deg, #eef3f9 0%, #f7f9fc 100%);
}

a {
    color: var(--brand);
    text-decoration: none;
}

.container {
    width: min(1100px, 94%);
    margin: 0 auto;
}

.site-header {
    background: #fff;
    border-bottom: 1px solid var(--border);
    margin-bottom: 1rem;
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.8rem 0;
}

nav {
    display: flex;
    gap: 0.8rem;
}

.panel {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 1rem;
    margin-bottom: 1rem;
}

.controls,
.scan-form {
    display: flex;
    gap: 0.8rem;
    flex-wrap: wrap;
    align-items: flex-end;
}

label {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
    font-size: 0.95rem;
}

input,
select,
button {
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 0.5rem 0.65rem;
    font-size: 0.95rem;
}

button {
    background: var(--brand);
    color: #fff;
    border: 0;
    cursor: pointer;
}

.viewer-layout {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 240px;
    gap: 1rem;
    margin-bottom: 2rem;
}

.map-wrap {
    position: relative;
    width: 100%;
    border: 1px solid var(--border);
    border-radius: 10px;
    overflow: hidden;
    background: #fff;
}

.map-wrap img {
    display: block;
    width: 100%;
    height: auto;
}

.grid-layer,
.heatmap-layer {
    position: absolute;
    inset: 0;
}

.grid-layer {
    pointer-events: none;
}

.scan-map .grid-layer,
.scan-map .heatmap-layer {
    pointer-events: none;
}

.legend {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 1rem;
    height: fit-content;
}

.swatch {
    width: 16px;
    height: 16px;
    display: inline-block;
    margin-right: 0.4rem;
    border-radius: 4px;
    vertical-align: middle;
    border: 1px solid #aaa;
}

.green {
    background: var(--strong);
}

.yellow {
    background: var(--medium);
}

.red {
    background: var(--weak);
}

.none {
    background: transparent;
}

.messages {
    list-style: none;
    margin: 0 0 1rem;
    padding: 0;
}

.messages li {
    padding: 0.6rem;
    border-radius: 6px;
    border: 1px solid var(--border);
    margin-bottom: 0.5rem;
    background: #fff;
}

.messages .success {
    border-color: #45ab73;
}

.messages .error {
    border-color: #da6060;
}

.cell-readout {
    padding: 0.45rem 0.65rem;
    border: 1px dashed var(--border);
    border-radius: 6px;
    min-height: 38px;
    display: flex;
    align-items: center;
}

.auth-panel {
    max-width: 500px;
}

.auth-form p {
    margin: 0 0 0.6rem;
}

@media (max-width: 900px) {
    .viewer-layout {
        grid-template-columns: 1fr;
    }
}