* {
  box-sizing: border-box;
}
body {
  font-family: 'Poppins', Arial, Helvetica, sans-serif;
  margin: 50px 0;
  background: linear-gradient(90deg, #4e54c8, #8f94fb);
  color: #333;
  display: flex;
  justify-content: center;
  align-items: center;
  height: auto;
}
.container {
  width: 90%;
  max-width: 500px;
  background: #ffffff;
  padding: 30px;
  border-radius: 15px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}
.container h1 {
  text-align: center;
  color: #2c3e50;
  font-size: 32px;
  margin-bottom: 20px;
  font-weight: bold;
}
.form {
  display: flex;
  gap: 10px;
  margin-bottom: 20px;
}
.input {
  flex: 1;
  padding: 12px;
  font-size: 16px;
  border: 1px solid #ddd;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  outline: none;
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}
.input:focus {
  border-color: #4e54c8;
  box-shadow: 0 0 5px rgba(78, 84, 200, 0.5);
}
.add {
  padding: 12px 20px;
  font-size: 15px;
  color: #fff;
  background: #4e54c8;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.3s ease, transform 0.2s ease;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}
.add:hover {
  background: #8f94fb;
  transform: scale(1.05);
}
.tasks {
  margin-top: 20px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.task {
  background: #f9f9f9;
  padding: 12px;
  border-radius: 8px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  transition: all 0.3s ease;
  line-height: 1.5;
  overflow: auto;
}
.task:hover {
  background: #f1f1f1;
}
.task.done {
  opacity: 0.6;
  text-decoration: line-through;
}
.task span {
  background: #e74c3c;
  color: #fff;
  padding: 6px 12px;
  border-radius: 5px;
  font-size: 12px;
  cursor: pointer;
  transition: all 0.3s ease;
}
.task span:hover {
  background: #c0392b;
}
.toggle-dark-mode {
  margin-top: 20px;
  padding: 12px;
  font-size: 12px;
  background: #2c3e50;
  color: #fff;
  border: none;
  border-radius: 360px;
  cursor: pointer;
  transition: all 0.3s ease, transform 0.2s ease;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
}
.toggle-dark-mode:hover {
  background: #34495e;
  transform: scale(1.05);
}
.task-counter {
  display: inline-block;
  font-size: 20px;
  font-weight: bold;
  color: #4e54c8;
  background: none;
  padding: 10px 20px;
  border-radius: 50px;
  border: 1px solid #4e54c8;
  margin-top: 10px;
  text-align: center;
}
.task-counter:hover {
  background: #4e54c8;
  color: #ffffff;
  transition: all 0.3s ease;
}
/* Dark Mode */
body.dark-mode {
  background: linear-gradient(90deg, #2c3e50, #34495e);
  color: #ecf0f1;
}
body.dark-mode .container {
  background: #3b4a59;
  color: #ecf0f1;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.5);
}
body.dark-mode .task-counter {
  color: #ffffff;
  border: 1px solid #8f94fb;
}
body.dark-mode .task-counter:hover {
  background: #8f94fb;
  color: #2c3e50;
  transition: all 0.3s ease;
}
body.dark-mode h1 {
  color: #ffffff;
}
body.dark-mode .input {
  background: #4a5a6a;
  color: #ecf0f1;
  border: 1px solid #5a6b7c;
}
body.dark-mode .input::placeholder {
  color: #bdc3c7;
}
body.dark-mode .add {
  background: #4e54c8;
  color: #ffffff;
}
body.dark-mode .add:hover {
  background: #8f94fb;
}
body.dark-mode .task {
  background: #4a5a6a;
  color: #ecf0f1;
  border: 1px solid #5a6b7c;
}
body.dark-mode .task span {
  background: #e74c3c;
  color: #ffffff;
}
body.dark-mode .task span:hover {
  background: #ff6f61;
}
body.dark-mode .toggle-dark-mode {
  background: #4e54c8;
  color: #ffffff;
}
body.dark-mode .toggle-dark-mode:hover {
  background: #8f94fb;
}

@media (max-width: 768px) {
  .container {
    padding: 20px;
  }
  .input,
  .add,
  .toggle-dark-mode {
    font-size: 13px;
    padding: 10px;
  }
  h1 {
    font-size: 24px;
  }
}

@media (min-width: 1024px) {
  .container {
    max-width: 600px;
  }
  h1 {
    font-size: 36px;
  }
  .input {
    font-size: 18px;
    padding: 14px;
  }
  .add {
    font-size: 16px;
    padding: 14px 24px;
  }
  .task {
    font-size: 16px;
    padding: 14px;
  }
  .toggle-dark-mode {
    font-size: 15px;
    padding: 14px;
  }
}