/* ===== Root Variables ===== */
:root {
  --primary-color: #000000;
  --accent-color: #ffffff;
  --secondary-color: #b71c1c;
  --light-bg: #f8f9fa;
  --card-bg: #ffffff;
  --shadow-color: rgba(0, 0, 0, 0.1);
  --spacing-unit: 1.5rem;
  --font-family: "Inter", sans-serif;
}

.hidden {
  display: none;
}

.placeholder {
  visibility: hidden;
}

/* Leaderboard Highlight for Current User */
.leaderboard tr.current-user {
  background-color: #e8f5e9 !important;
  font-weight: bold;
}

/* ===== Global Styles ===== */
body {
  font-family: var(--font-family);
  margin: 0;
  padding: 0;
  background-color: var(--light-bg);
  color: var(--primary-color);
}

/* ===== Header ===== */
.navbar {
  background: linear-gradient(45deg, var(--primary-color), var(--secondary-color), var(--primary-color));
  color: var(--accent-color);
  padding: 1rem 0;
  box-shadow: 0 4px 10px var(--shadow-color);
  width: 100%;
  position: sticky;
  top: 0;
  z-index: 1000;
}

.navbar-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1rem;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--accent-color);
  font-size: 1.75rem;
  font-weight: 600;
  text-decoration: none;
}

.logo {
  filter: drop-shadow(0 0 5px var(--accent-color));
  height: 50px;
  width: auto;
}

.navbar-buttons {
  display: flex;
  flex-direction: row;
  gap: 0.5rem;
}

#logout-button, #admin-button, #profile-button {
  background: none;
  border: 2px solid rgba(255, 255, 255, 0.3);
  color: var(--accent-color);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  padding: 0.5rem 1rem;
  border-radius: 8px;
  transition: background-color 0.3s ease, border-color 0.3s ease;
}

#logout-button:hover, #admin-button:hover, #profile-button:hover {
  background-color: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.6);
}

#profile-button {
  background-color: rgba(255, 255, 255, 0.1);
}

/* ===== Auth Pages (Login & Register) ===== */
.auth-container {
  max-width: 400px;
  margin: 2rem auto;
  padding: 2rem;
  background-color: var(--card-bg);
  border-radius: 10px;
  box-shadow: 0 4px 10px var(--shadow-color);
  text-align: center;
}

.auth-container h1 {
  color: var(--secondary-color);
  margin-bottom: 1.5rem;
  font-size: 1.75rem;
}

.auth-container form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.auth-container input {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--shadow-color);
  border-radius: 5px;
  background-color: var(--light-bg);
  color: var(--primary-color);
  font-size: 1rem;
}

.auth-container input:focus {
  outline: none;
  border-color: var(--secondary-color);
  box-shadow: 0 0 0 2px rgba(183, 28, 28, 0.2);
}

.auth-container button {
  width: 100%;
  padding: 0.75rem;
  border: none;
  border-radius: 5px;
  background-color: var(--secondary-color);
  color: var(--accent-color);
  font-size: 1rem;
  font-weight: bold;
  cursor: pointer;
  transition: background-color 0.3s ease;
}

.auth-container button:hover {
  background-color: #8e1c1c; /* Darker shade of secondary color */
}

.auth-container p {
  margin-top: 1rem;
  color: var(--primary-color);
}

.auth-container a {
  color: var(--secondary-color);
  text-decoration: none;
  font-weight: bold;
}

.auth-container a:hover {
  text-decoration: underline;
}

.error {
  color: var(--secondary-color);
  margin-top: 1rem;
  font-size: 0.9rem;
}

/* ===== Main Container ===== */
.container {
  padding: var(--spacing-unit);
  display: grid;
  grid-template-columns: 250px 1fr 250px;
  grid-template-rows: auto auto auto;
  gap: 1rem;
  align-items: start;
  max-width: 1200px;
  margin: 0 auto;
}

/* Current Level Items Section */
.current-level-items {
  grid-column: 1 / 2;
  grid-row: 1 / 4;
  padding: 1rem;
  background-color: transparent;
  box-shadow: none;
  border-radius: 0;
}

.current-level-items h3 {
  font-size: 1rem;
  color: var(--secondary-color);
  margin-bottom: 1rem;
}

.current-level-items ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.current-level-items li {
  padding: 0.5rem;
  margin: 0.25rem 0;
  border-radius: 4px;
  color: var(--primary-color);
}

.current-level-items .learned {
  background-color: #e8f5e9;
}

.current-level-items .unlearned {
  background-color: #f5f5f5;
}

.current-level-items .srs-stage {
  font-size: 0.8rem;
  color: #666;
  margin-left: 0.5rem;
}

/* Progress Section */
.progress-container {
  grid-column: 2 / 3;
  grid-row: 1 / 2;
  text-align: center;
  margin-bottom: 0;
}

.progress-bar {
  width: 100%;
  height: 20px;
  background-color: var(--light-bg);
  border-radius: 10px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background-color: var(--secondary-color);
  width: 0%;
}

#progress-text {
  font-size: 1.1rem;
  color: var(--primary-color);
}

#unlock-message {
  font-size: 1rem;
  color: var(--secondary-color);
  margin-top: 0.5rem;
}

/* Stats Section */
.stats {
  grid-column: 2 / 3;
  grid-row: 2 / 3;
  display: flex;
  justify-content: space-around;
  gap: 1rem;
  margin-top: 1rem;
}

.stat-card {
  background: var(--card-bg);
  padding: 1rem;
  border-radius: 8px;
  box-shadow: 0 4px 6px var(--shadow-color);
  text-align: center;
  cursor: pointer;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  flex: 1;
}

.stat-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 6px 10px rgba(0, 0, 0, 0.2);
}

.stat-card h3 {
  margin: 0;
  font-size: 1.2rem;
  color: var(--secondary-color);
}

.stat-card p {
  font-size: 2rem;
  margin: 0.5rem 0 0;
  color: var(--primary-color);
}

#next-review-section {
  font-size: 0.5rem;
  color: #666;
  margin-top: 0.5rem;
}

#next-review-time-label {
  font-size: 0.5rem;
  color: #888;
}

/* Belts Section */
.belts-section {
  grid-column: 2 / 3;
  grid-row: 3 / 4;
  margin-top: 1rem;
}

.belt-cards {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: space-between;
}

.belt-card {
  background: var(--card-bg);
  padding: 0.5rem 0.75rem;
  border-radius: 8px;
  box-shadow: 0 4px 6px var(--shadow-color);
  text-align: center;
  flex: 1 1 calc(20% - 1rem);
  cursor: pointer;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  min-height: auto;
}

.belt-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 6px 10px rgba(0, 0, 0, 0.2);
}

.belt-card h3 {
  margin: 0;
  font-size: 1rem;
  color: var(--secondary-color);
}

.belt-card p {
  font-size: 0.875rem;
  margin: 0.25rem 0 0;
  color: var(--primary-color);
}

/* Belt Colors */
.belt-card[data-belt="white"] {
  background-color: #ffffff;
}

.belt-card[data-belt="white"] h3,
.belt-card[data-belt="white"] p {
  color: var(--primary-color);
}

.belt-card[data-belt="yellow"] {
  background-color: #ffeb3b;
}

.belt-card[data-belt="yellow"] h3,
.belt-card[data-belt="yellow"] p {
  color: #000000;
}

.belt-card[data-belt="green"] {
  background-color: #4caf50;
}

.belt-card[data-belt="green"] h3,
.belt-card[data-belt="green"] p {
  color: #ffffff;
}

.belt-card[data-belt="brown"] {
  background-color: #795548;
}

.belt-card[data-belt="brown"] h3,
.belt-card[data-belt="brown"] p {
  color: #ffffff;
}

.belt-card[data-belt="black"] {
  background-color: #000000;
}

.belt-card[data-belt="black"] h3,
.belt-card[data-belt="black"] p {
  color: #ffffff;
}

/* Leaderboard Section */
.leaderboard {
  grid-column: 3 / 4;
  grid-row: 1 / 4;
  margin-top: 0;
}

.leaderboard table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1rem;
}

.leaderboard th,
.leaderboard td {
  padding: 0.75rem;
  text-align: center;
  border-bottom: 1px solid var(--shadow-color);
}

.leaderboard th {
  background-color: var(--secondary-color);
  color: var(--accent-color);
  font-weight: 600;
}

.leaderboard tr:nth-child(even) {
  background-color: var(--light-bg);
}

.leaderboard tr:hover {
  background-color: rgba(0, 0, 0, 0.05);
}

/* Achievement Notifications */
.achievement-notification {
  position: fixed;
  top: 20px;
  right: 20px;
  background: var(--secondary-color);
  color: white;
  padding: 15px;
  border-radius: 5px;
  box-shadow: 0 2px 10px rgba(0,0,0,0.2);
  z-index: 1000;
  animation: slideIn 0.5s ease-out;
  max-width: 300px;
}

.achievement-notification h4 {
  margin: 0 0 5px 0;
  font-size: 1.1rem;
}

.achievement-notification p {
  margin: 0;
  font-size: 0.9rem;
}

.achievement-notification.fade-out {
  animation: fadeOut 0.5s ease-in;
}

@keyframes slideIn {
  from { transform: translateX(100%); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}

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

/* Achievements Section */
.achievements-section {
/*  background-color: var(--card-bg); */
  padding: 20px;
  margin-bottom: 20px;
  border-radius: 10px;
 /* box-shadow: 0 4px 6px var(--shadow-color); */
}

.achievements-section h3 {
  margin-top: 0;
  color: var(--secondary-color);
  border-bottom: 1px solid var(--shadow-color);
  padding-bottom: 10px;
}

#recent-achievements-list {
  list-style-type: none;
  padding: 0;
  margin: 0;
}

#recent-achievements-list li {
  background-color: var(--light-bg);
  padding: 12px;
  margin-bottom: 8px;
  border-radius: 5px;
  box-shadow: 0 2px 4px var(--shadow-color);
  transition: transform 0.2s ease;
}

#recent-achievements-list li:hover {
  transform: translateY(-2px);
}

#recent-achievements-list li strong {
  display: block;
  font-size: 1rem;
  color: var(--secondary-color);
  margin-bottom: 4px;
}

#recent-achievements-list li span {
  display: block;
  font-size: 0.9rem;
  color: var(--primary-color);
  margin-bottom: 4px;
}

#recent-achievements-list li small {
  display: block;
  font-size: 0.8rem;
  color: #666;
}

/* Belt Terms Popup Styles */
.popup {
  display: none;
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
}

.popup-content {
  background-color: #fefefe;
  margin: 10% auto;
  padding: 20px;
  border: 1px solid #888;
  width: 80%;
  max-width: 600px;
  max-height: 70vh;
  overflow-y: auto;
  border-radius: 8px;
  position: relative;
}

.close-popup {
  position: absolute;
  right: 15px;
  top: 10px;
  font-size: 24px;
  cursor: pointer;
}

.close-popup:hover {
  color: #666;
}

#belt-terms-list {
  margin-top: 1rem;
}

#belt-terms-list ul {
  list-style: none;
  padding: 0;
}

#belt-terms-list li {
  padding: 0.5rem;
  margin: 0.25rem 0;
  border-radius: 4px;
  background-color: #f5f5f5;
}

.srs-stage {
  font-size: 0.8rem;
  color: #666;
  margin-left: 0.5rem;
}

/* Responsive Design */
@media (max-width: 768px) {
  .container {
    grid-template-columns: 1fr;
    grid-template-rows: auto;
    gap: 1rem;
    padding: 1rem;
  }

  .current-level-items {
    grid-column: 1 / 2;
    grid-row: 2;
  }

  .progress-container {
    grid-column: 1 / 2;
    grid-row: 1;
  }

  .stats {
    grid-column: 1 / 2;
    grid-row: auto;
    flex-direction: column;
  }

  .belts-section {
    grid-column: 1 / 2;
    grid-row: auto;
  }

  .leaderboard {
    grid-column: 1 / 2;
    grid-row: auto;
  }

  .belt-cards {
    flex-direction: column;
  }

  .belt-card {
    flex: 1 1 100%;
  }

  /* Smaller header buttons on mobile */
  .navbar-buttons {
    gap: 0.3rem;
  }

  #logout-button,
  #admin-button,
  #profile-button {
    padding: 0.3rem 0.6rem;
    font-size: 0.85rem;
  }

  /* Smaller popup on mobile */
  .popup-content {
    width: 90%;
    margin: 15% auto;
    padding: 15px;
  }

  /* Adjust popup title size */
  #popup-title {
    font-size: 1.2rem;
    padding-right: 20px;
  }

  /* Adjust popup content */
  #belt-terms-list li {
    padding: 0.4rem;
    font-size: 0.9rem;
  }

  .srs-stage {
    font-size: 0.7rem;
  }

  .achievements-section {
    order: 5;
    margin-top: 1rem;
  }
}

@media (max-width: 480px) {
  /* Even smaller adjustments for very small screens */
  .popup-content {
    margin: 20% auto;
    max-height: 60vh;
  }

  .navbar-buttons {
    gap: 0.2rem;
  }

  #logout-button,
  #admin-button,
  #profile-button {
    padding: 0.25rem 0.5rem;
    font-size: 0.8rem;
  }

  /* Adjust belt cards for very small screens */
  .belt-card h3 {
    font-size: 0.9rem;
  }

  .belt-card p {
    font-size: 0.8rem;
  }
}