:root {
  --bg: #f4f6fb;
  --card: #ffffff;
  --text: #1f2937;
  --accent: #0f766e;
  --border: #d1d5db;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #eef2ff 0%, #ecfeff 100%);
  color: var(--text);
}

.container {
  max-width: 1000px;
  margin: 0 auto;
  padding: 28px 24px 36px;
  display: flex;
  flex-direction: column;
  gap: 22px;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 12px;
}

.auth-user {
  font-size: 0.9rem;
  color: #374151;
}

.logout-link {
  color: #0f766e;
  text-decoration: none;
  font-weight: 600;
}

h1 {
  text-align: center;
  margin: 0;
}

.split-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.panel {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 18px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
}

.expense-list {
  min-height: 120px;
  padding-left: 18px;
  margin: 12px 0 14px;
}

.expense-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 8px;
}

.delete-btn {
  background: #b91c1c;
  color: #fff;
  border: 1px solid #b91c1c;
  border-radius: 6px;
  padding: 4px 8px;
  font-size: 0.8rem;
  line-height: 1;
}

.total {
  font-weight: 600;
}

form {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr)) auto;
  gap: 12px;
  align-items: end;
}

label {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 0.92rem;
}

input,
select,
button {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px;
  font-size: 0.95rem;
}

button {
  background: var(--accent);
  color: white;
  cursor: pointer;
}

.calculator .result {
  margin-bottom: 0;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--accent);
}

.hidden {
  display: none;
}

.modal-overlay {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(17, 24, 39, 0.5);
  padding: 16px;
  z-index: 1000;
}

.modal-overlay.hidden {
  display: none;
}

.modal-card {
  width: min(420px, 100%);
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 18px;
  box-shadow: 0 18px 40px rgba(0, 0, 0, 0.2);
}

.modal-card h3 {
  margin: 0 0 8px;
}

.modal-card p {
  margin: 0 0 16px;
}

.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
}

.modal-actions button {
  padding: 8px 12px;
}

.modal-btn-cancel {
  background: #fff;
  color: var(--text);
}

.modal-btn-delete {
  background: #b91c1c;
  border-color: #b91c1c;
  color: #fff;
}

.auth-container {
  min-height: 100vh;
  justify-content: center;
}

.auth-panel {
  max-width: 420px;
  width: 100%;
  margin: 0 auto;
}

.auth-panel h1 {
  margin-bottom: 8px;
}

.auth-panel h2 {
  margin-top: 0;
}

.auth-form {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.auth-error {
  margin: 0 0 12px;
  color: #b91c1c;
  font-weight: 600;
}

@media (max-width: 760px) {
  .container {
    padding: 18px 14px 28px;
    gap: 16px;
  }

  .split-grid {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  form {
    grid-template-columns: 1fr;
    gap: 10px;
  }

  .panel {
    padding: 14px;
  }

  .expense-list {
    min-height: 0;
    margin: 10px 0 12px;
  }

  .expense-item {
    gap: 8px;
  }
}