* { box-sizing: border-box; }
body { font-family: system-ui, -apple-system, Segoe UI, Roboto, sans-serif; margin:0; background:#f7f7fb; color:#222; }
a { color:#0b6bcb; text-decoration:none; }
.topbar { display:flex; justify-content:space-between; align-items:center; padding:12px 16px; background:#fff; border-bottom:1px solid #e5e7eb; position:sticky; top:0; }
.topbar .brand { font-weight:700; }
.container { max-width: 1000px; margin: 24px auto; padding: 0 16px; }
.container.narrow { max-width: 480px; }
.alert { padding:12px 14px; border-radius:8px; margin:12px 0; }
.alert-warn { background:#fff8e1; border:1px solid #ffecb3; }
.alert-error { background:#fde7e9; border:1px solid #f9c2c7; }
.btn { background:#0b6bcb; color:#fff; padding:10px 14px; border:none; border-radius:8px; cursor:pointer; }
label { display:block; margin:10px 0; }
input, select { width:100%; padding:10px; border:1px solid #d1d5db; border-radius:8px; background:#fff; }
table { width:100%; border-collapse: collapse; background:#fff; }
th, td { padding:10px; border-bottom:1px solid #eee; text-align:left; }
.actions a { margin-right:8px; }
.tank-wrap { display:flex; gap:24px; align-items:flex-end; margin-top: 16px; }
.tank {
  position: relative; width: 220px; height: 360px;
  border: 4px solid #555; border-radius: 18px 18px 10px 10px; overflow: hidden;
  background: #f2f2f2;
}
.tank::before { /* neck */
  content:""; position:absolute; top:-24px; left:40px; right:40px; height:24px;
  border:4px solid #555; border-bottom:none; border-radius:18px 18px 0 0; background:#fafafa;
}
.water {
  position: absolute; bottom: 0; left: 0; right: 0; height: 0%;
  background: linear-gradient(180deg, rgba(0,150,255,0.9), rgba(0,110,220,0.95));
  transition: height 1s ease-in-out;
  background-size: 200% 200%;
  animation: wave 6s infinite linear;
}
@keyframes wave { 0% { background-position: 0% 50%; } 100% { background-position: 200% 50%; } }
.stats { min-width: 320px; background:#fff; border:1px solid #eee; border-radius:12px; padding:16px; }
.stat { margin: 8px 0; }
.big { font-size: 24px; font-weight: 700; }
.muted { color: #666; }
.admin-toolbar { margin:12px 0; display:flex; gap:8px; }