:root {
  --bg: #0f1117;
  --panel: #171a24;
  --panel-2: #1e222e;
  --border: #2a2f3d;
  --text: #e8e9ee;
  --muted: #9099ab;
  --accent: #6366f1;
  --accent-2: #818cf8;
  --green: #22c55e;
  --red: #ef4444;
  --radius: 12px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

a { color: var(--accent-2); text-decoration: none; }
a:hover { text-decoration: underline; }

/* --- Topbar & Navigation Layout --- */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 24px;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  position: relative; /* Crucial for absolute dropdown placement */
}

.topbar .brand { font-weight: 700; font-size: 1.2rem; color: var(--text); }
.topbar .brand span { color: var(--accent-2); }

.topbar nav { display: flex; gap: 16px; align-items: center; }
.topbar nav a { color: var(--muted); font-size: 0.92rem; }
.topbar nav a.active, .topbar nav a:hover { color: var(--text); }

.topbar nav form { display: inline-flex; }

/* Menu Toggle Button Style */
.menu-toggle {
  display: none; /* Hidden on desktop screens */
  background: none;
  border: none;
  color: var(--text);
  font-size: 1.6rem;
  cursor: pointer;
  padding: 4px;
  line-height: 1;
}

/* Container for sub-links (Desktop behavior) */
.sub-links {
  display: flex;
  gap: 12px;
  align-items: center;
}

/* --- Content & UI Components --- */
.container { max-width: 980px; margin: 0 auto; padding: 24px; margin-top: -28px; }

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  margin-bottom: 20px;
}

.card h2, .card h3 { margin-top: 0; }

.grid { display: grid; gap: 16px; }
.grid.cols-2 { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }
.grid.cols-3 { grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); }

.stat {
  background: var(--panel-2);
  border-radius: var(--radius);
  padding: 10px;
  border: 1px solid var(--border);
}
.stat .label { color: var(--muted); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.04em; }
.stat .slabel { color: var(--muted); font-size: 0.5rem; text-transform: uppercase; letter-spacing: 0.04em; }

.stat .value { font-size: 1.6rem; font-weight: 700; margin-top: 4px; }
.value.positive { color: var(--green); }
.value.negative { color: var(--red); }

.btn {
  display: inline-block;
  background: var(--accent);
  color: white;
  border: none;
  padding: 9px 16px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 600;
}
.btn:hover { background: var(--accent-2); text-decoration: none; }
.btn.secondary { background: transparent; border: 1px solid var(--border); color: var(--text); }
.btn.danger { background: var(--red); }
.btn.small { padding: 5px 10px; font-size: 0.8rem; }

.input {
  width: 100%;
  padding: 9px 12px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--panel-2);
  color: var(--text);
  font-size: 0.92rem;
}

form p { margin: 12px 0; }
label { display: block; margin-bottom: 4px; color: var(--muted); font-size: 0.85rem; }
slabel { display: block; margin-bottom: 4px; color: var(--muted); font-size: 0.5rem; }


table { width: 100%; border-collapse: collapse; }
th, td { text-align: left; padding: 10px 8px; border-bottom: 1px solid var(--border); font-size: 0.9rem; }
th { color: var(--muted); font-weight: 600; font-size: 0.78rem; text-transform: uppercase; }

.badge {
  display: inline-block;
  padding: 2px 9px;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 600;
  background: var(--panel-2);
  border: 1px solid var(--border);
}
.badge.admin { background: rgba(99,102,241,0.2); color: var(--accent-2); border-color: var(--accent); }

.messages { list-style: none; padding: 0; margin: 0 0 16px; }
.messages li {
  padding: 10px 14px;
  border-radius: 8px;
  margin-bottom: 8px;
  font-size: 0.9rem;
  border: 1px solid var(--border);
}
.messages li.success { background: rgba(34,197,94,0.12); border-color: var(--green); }
.messages li.error { background: rgba(239,68,68,0.12); border-color: var(--red); }

.avatar {
  width: 32px; height: 32px; border-radius: 50%;
  display: inline-flex; align-items: center; justify-content: center;
  color: white; font-weight: 700; font-size: 0.85rem;
}

.muted { color: var(--muted); }
.flex { display: flex; align-items: center; gap: 10px; }
.flex.between { justify-content: space-between; }
.mt-0 { margin-top: 0; }
hr { border: none; border-top: 1px solid var(--border); margin: 16px 0; }

.split-row { display: grid; grid-template-columns: 1fr 120px; gap: 10px; align-items: center; padding: 6px 0; }
.empty-state { color: var(--muted); text-align: center; padding: 30px 0; }

/* --- Mobile Breakpoint (Dropdown Layout) --- */
@media (max-width: 768px) {
  .menu-toggle {
    display: block; /* Reveal hamburger icon */
  }

  .topbar nav {
    display: none; /* Keep menu completely hidden by default */
    flex-direction: column;
    align-items: stretch;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--panel);
    border-bottom: 1px solid var(--border);
    padding: 16px 24px;
    gap: 12px;
    z-index: 100;
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.4);
  }

  /* Explicit selector triggered by JavaScript toggle class */
  .topbar nav.active {
    display: flex;
  }

  .topbar nav a {
    font-size: 1rem;
    padding: 6px 0;
    border-bottom: 1px solid rgba(42, 47, 61, 0.4); /* subtle separator */
  }
  
  .topbar nav a:last-of-type {
    border-bottom: none;
  }

  /* Format nested mobile group items */
  .sub-links {
    flex-direction: column;
    align-items: flex-start;
    padding-left: 16px;
    gap: 8px;
    margin-top: -4px;
    margin-bottom: 4px;
  }

  .sub-links a {
    width: 100%;
    font-size: 0.88rem !important;
    border-bottom: none;
    padding: 2px 0;
  }

  /* Make form layout fit full-width comfortably */
  .topbar nav form {
    width: 100%;
    margin-top: 6px;
  }

  .topbar nav form .btn {
    width: 100%;
    text-align: center;
    padding: 10px;
  }
}


/* --- Modern Expense List Design --- */
.expense-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 12px; /* Breathing room between items */
}

.expense-item {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 18px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: transform 0.15s ease, border-color 0.15s ease;
}

.expense-item:hover {
  border-color: var(--accent-2);
  transform: translateY(-1px);
}

.expense-left {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.expense-title {
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--text);
}

.expense-title:hover {
  color: var(--accent-2);
}

.expense-meta {
  font-size: 0.85rem;
  color: var(--muted);
  display: flex;
  align-items: center;
  gap: 6px;
}

.expense-meta .dot {
  color: var(--border);
}

.expense-right {
  text-align: right;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 6px;
}

.expense-amount {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text);
}

/* Responsive adjustment for small phone screens */
@media (max-width: 480px) {
  .expense-item {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }
  .expense-right {
    width: 100%;
    flex-direction: row-reverse;
    justify-content: space-between;
    align-items: center;
    border-top: 1px solid var(--border);
    padding-top: 10px;
  }
}