/* ---------- WeightChart dark theme ---------- */
:root {
  --bg: #0b0f14;
  --bg-elev: #121821;
  --bg-elev2: #1a2330;
  --border: #24303f;
  --text: #e6edf3;
  --text-dim: #8b98a5;
  --accent: #34d399;
  --accent-dim: #10b98122;
  --danger: #f87171;
  --radius: 12px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  font-size: 15px;
}

/* subtle top glow */
body::before {
  content: "";
  position: fixed; inset: 0 0 auto 0; height: 320px;
  background: radial-gradient(600px 200px at 50% -50px, var(--accent-dim), transparent);
  pointer-events: none;
}

.container { max-width: 1100px; margin: 0 auto; padding: 20px 16px 60px; }
.muted { color: var(--text-dim); }
.small { font-size: 12.5px; }
code { background: var(--bg-elev2); padding: 1px 5px; border-radius: 4px; font-size: 12px; }

/* ---------- header ---------- */
.topbar {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; gap: 14px; flex-wrap: wrap;
  padding: 12px 18px;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.brand { display: flex; align-items: center; gap: 8px; font-weight: 700; font-size: 17px; }
.brand-icon { font-size: 20px; }

.user-pills { display: flex; gap: 6px; flex-wrap: wrap; flex: 1; }
.user-pill {
  border: 1px solid var(--border); background: var(--bg-elev); color: var(--text-dim);
  padding: 6px 14px; border-radius: 999px; cursor: pointer; font-size: 13.5px;
  transition: all .15s ease;
}
.user-pill:hover { color: var(--text); border-color: var(--accent); }
.user-pill.active {
  background: var(--accent-dim); color: var(--accent); border-color: var(--accent); font-weight: 600;
}

/* ---------- buttons ---------- */
.btn {
  border: 1px solid var(--border); background: var(--bg-elev); color: var(--text);
  border-radius: 8px; padding: 7px 13px; cursor: pointer; font-size: 13.5px;
  transition: all .15s ease;
}
.btn:hover { border-color: var(--accent); }
.btn-primary { background: var(--accent); color: #052e1c; font-weight: 600; border-color: transparent; }
.btn-primary:hover { filter: brightness(1.08); }
.btn-ghost { background: transparent; }
.btn-sm { padding: 5px 10px; font-size: 12.5px; }
.btn-chip { padding: 4px 11px; border-radius: 999px; font-size: 12.5px; color: var(--text-dim); }
.btn-chip.active { background: var(--accent-dim); color: var(--accent); border-color: var(--accent); }
.btn-danger { color: var(--danger); border-color: transparent; background: transparent; }
.btn-danger:hover { border-color: var(--danger); }

/* ---------- cards ---------- */
.card {
  background: var(--bg-elev); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 18px; margin-bottom: 16px;
}
.card-head { display: flex; align-items: baseline; gap: 12px; flex-wrap: wrap; margin-bottom: 12px; }
.card-head h2 { margin: 0; font-size: 15.5px; }

/* ---------- dropzone ---------- */
.dropzone {
  border: 2px dashed var(--border); border-radius: var(--radius);
  padding: 26px; text-align: center; cursor: pointer;
  transition: all .15s ease;
}
.dropzone:hover, .dropzone:focus-visible, .dropzone.dragover {
  border-color: var(--accent); background: var(--accent-dim);
}
.dz-icon { font-size: 26px; margin-bottom: 6px; }

.upload-status { margin-top: 12px; padding: 10px 14px; border-radius: 8px; font-size: 13.5px; }
.upload-status.ok  { background: var(--accent-dim); color: var(--accent); }
.upload-status.err { background: #f8717122; color: var(--danger); }

/* ---------- controls ---------- */
.controls { display: flex; gap: 28px; flex-wrap: wrap; }
.control-group label {
  display: block; font-size: 11.5px; text-transform: uppercase; letter-spacing: .06em;
  color: var(--text-dim); margin-bottom: 7px;
}
.preset-row { display: inline-flex; gap: 5px; margin-bottom: 9px; flex-wrap: wrap; }
.preset-row .btn-chip.active { background: var(--accent); color: #052e1c; }
.date-inputs, .weight-inputs { display: flex; align-items: center; gap: 7px; flex-wrap: wrap; }
.weight-inputs { max-width: 340px; }

input[type="date"], input[type="number"], input[type="text"] {
  background: var(--bg-elev2); color: var(--text); border: 1px solid var(--border);
  border-radius: 8px; padding: 6px 9px; font-size: 13.5px; color-scheme: dark;
}
input:focus { outline: none; border-color: var(--accent); }
#new-user-name { flex: 1; }

/* ---------- chart tabs ---------- */
.engine-tabs { display: flex; gap: 4px; margin-bottom: -1px; overflow-x: auto; }
.engine-tabs button {
  background: var(--bg-elev); border: 1px solid var(--border); color: var(--text-dim);
  padding: 8px 16px; border-radius: 10px 10px 0 0; cursor: pointer; font-size: 13px;
  white-space: nowrap;
}
.engine-tabs button:hover { color: var(--text); }
.engine-tabs button.active {
  color: var(--accent); border-bottom-color: var(--bg-elev);
  background: var(--bg-elev); position: relative; z-index: 1;
}
.chart-card { min-height: 420px; }
#chart-container { width: 100%; height: 440px; }
#chart-container > * { width: 100% !important; }

.chart-empty, .empty-state { text-align: center; padding: 40px 20px; color: var(--text-dim); }

/* ---------- dialog ---------- */
.dialog { background: var(--bg-elev); color: var(--text); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 0; max-width: 430px; width: 92vw; }
.dialog::backdrop { background: rgba(0,0,0,.6); backdrop-filter: blur(3px); }
.dialog-body { padding: 20px; }
.dialog-body h2 { margin: 0 0 14px; font-size: 16px; }
.users-list { display: flex; flex-direction: column; gap: 6px; margin-bottom: 14px; max-height: 260px; overflow-y: auto; }
.user-row { display: flex; align-items: center; justify-content: space-between; gap: 10px;
  background: var(--bg-elev2); border-radius: 8px; padding: 8px 12px; font-size: 14px; }
.user-row .meta { color: var(--text-dim); font-size: 12px; }
.add-user-row { display: flex; gap: 8px; margin-bottom: 16px; }
.dialog-actions { display: flex; justify-content: flex-end; }

/* ---------- toast ---------- */
.toast-holder { position: fixed; bottom: 18px; right: 18px; z-index: 100;
  display: flex; flex-direction: column; gap: 8px; }
.toast {
  background: var(--bg-elev2); border: 1px solid var(--border); border-left: 3px solid var(--accent);
  color: var(--text); padding: 10px 16px; border-radius: 8px; font-size: 13.5px;
  box-shadow: 0 8px 30px rgba(0,0,0,.45);
  animation: slide-in .25s ease;
}
.toast.error { border-left-color: var(--danger); }
@keyframes slide-in { from { transform: translateY(12px); opacity: 0; } to { transform: none; opacity: 1; } }

/* ---------- responsive ---------- */
@media (max-width: 640px) {
  .topbar { padding: 10px 12px; }
  .brand-name { font-size: 15px; }
  .container { padding: 14px 10px 50px; }
  .controls { gap: 16px; }
  .date-inputs input[type="date"] { flex: 1; min-width: 118px; }
  #chart-container { height: 330px; }
  .chart-card { min-height: 310px; }
}