:root {
  --bg-light: #f5f7fa;
  --bg-dark: #1a252f;
  --card-bg: #ffffff;
  --card-dark: #2a3b4d;
  --text-light: #1e2a38;
  --text-dark: #d1d8e0;
  --primary: #4a6fa5;
  --accent: #2ecc71;
  --danger: #e74c3c;
  --border-radius: 8px;
  --shadow-light: 0 2px 10px rgba(0, 0, 0, 0.05);
  --shadow-dark: 0 4px 15px rgba(0, 0, 0, 0.15);
  --transition: all 0.25s ease-in-out;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Inter', sans-serif;
}

body {
  margin: 0;
  padding: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg-light);
  color: var(--text-light);
}

body.light {
  background: var(--bg-light);
  color: var(--text-light);
}

body.dark {
  background: var(--bg-dark);
  color: var(--text-dark);
}

header nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--primary);
  color: #ffffff;
  padding: 1.2rem 2rem;
  box-shadow: var(--shadow-light);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.logo {
  font-weight: 800;
  font-size: 1.6rem;
  letter-spacing: 1px;
}

nav ul {
  display: flex;
  gap: 1.5rem;
  list-style: none;
}

.tab-btn {
  background: none;
  color: #ffffff;
  border: none;
  padding: 0.75rem 1.25rem;
  font-size: 1rem;
  cursor: pointer;
  border-radius: var(--border-radius) var(--border-radius) 0 0;
  transition: var(--transition);
}

.tab-btn:hover {
  background: rgba(255, 255, 255, 0.1);
}

.tab-btn.active {
  background: rgba(255, 255, 255, 0.15);
  border-bottom: 3px solid var(--accent);
}

.side-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

#toggle-theme {
  background: none;
  border: none;
  color: #ffffff;
  font-size: 1.3rem;
  cursor: pointer;
  transition: var(--transition);
}

#toggle-theme:hover {
  color: var(--accent);
}

#user-info {
  font-size: 0.95rem;
  font-weight: 500;
}

#logout-btn {
  background: var(--danger);
  color: #ffffff;
  border: none;
  padding: 0.5rem 1.25rem;
  border-radius: var(--border-radius);
  cursor: pointer;
  font-weight: 600;
  transition: var(--transition);
}

#logout-btn:hover {
  background: #c0392b;
  transform: translateY(-2px);
}

main {
  padding: 2rem;
  max-width: 1200px;
  margin: 0 auto;
  flex: 1 0 auto;
}

.tab {
  display: none;
  animation: fadeIn 0.3s ease-out;
}

.tab.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.measure-form {
  background: var(--card-bg);
  padding: 1.5rem;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-light);
  margin: 0 auto 1.5rem;
  max-width: 600px;
}

body.dark .measure-form {
  background: var(--card-dark);
  box-shadow: var(--shadow-dark);
}

.measure-form h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 1rem;
  text-align: center;
  color: var(--primary);
}

.measure-form label {
  display: flex;
  flex-direction: column;
  margin-bottom: 0.75rem;
  font-weight: 500;
}

.measure-form select,
.measure-form input {
  padding: 0.7rem;
  border: 1px solid #e2e8f0;
  border-radius: var(--border-radius);
  font-size: 1rem;
  transition: var(--transition);
  margin-top: 0.25rem;
}

body.dark .measure-form select,
body.dark .measure-form input {
  background: var(--card-dark);
  color: var(--text-dark);
  border-color: #4a5568;
}

.measure-form select:focus,
.measure-form input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(74, 111, 165, 0.2);
}

.measure-form button {
  background: var(--accent);
  color: #ffffff;
  border: none;
  padding: 0.7rem 1.2rem;
  border-radius: var(--border-radius);
  font-weight: 600;
  cursor: pointer;
  width: 100%;
  transition: var(--transition);
}

.measure-form button:hover {
  background: #27ae60;
  transform: translateY(-2px);
}

.card-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

.card {
  background: var(--card-bg);
  color: var(--text-light);
  border-radius: var(--border-radius);
  padding: 1.2rem;
  box-shadow: var(--shadow-light);
  transition: var(--transition);
}

body.dark .card {
  background: var(--card-dark);
  box-shadow: var(--shadow-dark);
}

.card:hover {
  transform: translateY(-3px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.card .card-title {
  font-weight: 700;
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
}

.card .card-subtitle {
  font-size: 0.9rem;
  color: var(--accent);
}

.chart-container {
  margin: 1.5rem auto;
  max-width: 600px;
  position: relative;
  height: 300px; /* Aumentei pra acomodar os dois datasets */
  background: var(--card-bg);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-light);
  padding: 1rem;
}

body.dark .chart-container {
  background: var(--card-dark);
  box-shadow: var(--shadow-dark);
}

canvas {
  max-width: 100%;
  height: auto !important;
}

.action-btn {
  background: var(--primary);
  color: #ffffff;
  border: none;
  padding: 0.8rem 1.5rem;
  border-radius: var(--border-radius);
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  display: block;
  margin: 0 auto;
}

.action-btn:hover {
  background: #396391;
  transform: translateY(-2px);
}

footer {
  flex-shrink: 0;
  background: var(--primary);
  color: #ffffff;
  text-align: center;
  padding: 1rem;
  margin-top: auto;
}

.hidden {
  display: none !important;
}

.loader {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 1.5rem;
  color: var(--primary);
}

.login-screen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(0, 0, 0, 0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1001;
  animation: fadeIn 0.3s ease-out;
}

.login-card {
  background: var(--card-bg);
  color: var(--text-light);
  padding: 2rem;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-dark);
  width: 90%;
  max-width: 400px;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  align-items: center;
  text-align: center;
}

body.dark .login-card {
  background: var(--card-dark);
  color: var(--text-dark);
}

.login-card h2 {
  font-size: 2rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
  color: var(--primary);
}

.login-card p {
  font-size: 1rem;
  opacity: 0.85;
  margin-bottom: 1rem;
}

.login-card input {
  width: 100%;
  padding: 0.9rem;
  border: 2px solid #e0e6ed;
  border-radius: var(--border-radius);
  font-size: 1rem;
  transition: var(--transition);
  background: #f9fafb;
  margin-top: 5px;
}

body.dark .login-card input {
  background: #2d3a4b;
  color: var(--text-dark);
  border-color: #4a5568;
}

.login-card input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(46, 204, 113, 0.3);
}

.login-card button {
  width: 100%;
  background: var(--accent);
  color: #ffffff;
  border: none;
  padding: 1rem;
  border-radius: var(--border-radius);
  font-weight: 700;
  cursor: pointer;
  transition: var(--transition);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-top: 5px;
}

.login-card button:hover {
  background: #27ae60;
  transform: translateY(-2px);
}

.login-card #login-err {
  color: var(--danger);
  font-size: 0.9rem;
  text-align: center;
  padding-top: 0.5rem;
}

@media (max-width: 768px) {
  nav {
    flex-direction: column;
    gap: 1rem;
    padding: 1rem;
  }

  nav ul {
    flex-direction: column;
    align-items: center;
    width: 100%;
  }

  .tab-btn {
    width: 100%;
    text-align: center;
  }

  main {
    padding: 1rem;
  }

  .measure-form {
    padding: 1rem;
    max-width: 100%;
  }

  .chart-container {
    max-width: 100%;
    height: 250px;
  }

  .action-btn {
    width: 100%;
  }

  .login-card {
    padding: 1.5rem;
    max-width: 320px;
  }

  .login-card h2 {
    font-size: 1.6rem;
  }
}

@media (max-width: 480px) {
  nav .logo {
    font-size: 1.4rem;
  }

  .measure-form h2 {
    font-size: 1.3rem;
  }

  .card-list {
    grid-template-columns: 1fr;
  }

  .chart-container {
    height: 200px;
  }

  .login-card {
    max-width: 280px;
    padding: 1.2rem;
  }

  .login-card h2 {
    font-size: 1.4rem;
  }

  .login-card input {
    padding: 0.7rem;
  }

  .login-card button {
    padding: 0.8rem;
  }
}