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

body {
  height: 100vh;
  background: #f8fafc;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* MAIN CONTAINER */
.container {
  width: 820px;
  height: 480px;
  background: white;
  display: flex;
  border-radius: 20px;
  overflow: hidden;
  box-shadow: 0 30px 80px rgba(0,0,0,0.1);
  transition: transform 0.8s cubic-bezier(.77,0,.18,1);
}

/* PANELS */
.panel {
  width: 50%;
  padding: 60px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  transition: transform 0.8s cubic-bezier(.77,0,.18,1);
}

/* BLUE SIDE */
.panel-left {
  background: #2563eb;
  color: white;
  text-align: center;
}

.panel-left h2 {
  font-size: 32px;
  margin-bottom: 12px;
}

.panel-left p {
  opacity: 0.9;
  margin-bottom: 30px;
}

.panel-left button {
  padding: 14px 40px;
  border-radius: 999px;
  border: none;
  background: white;
  color: #2563eb;
  font-weight: 600;
  cursor: pointer;
}

/* WHITE SIDE */
.panel-right {
  position: relative;
  background: white;
}

/* FORMS */
.form {
  position: absolute;
  inset: 0;
  padding: 60px;
  display: flex;
  flex-direction: column;
  gap: 18px;
  opacity: 0;
  transform: translateX(40px);
  transition: 0.6s ease;
}

.form h2 {
  font-size: 28px;
  margin-bottom: 10px;
  color: #0f172a;
}

.form input {
  padding: 14px;
  border-radius: 10px;
  border: 1px solid #e5e7eb;
}

.form button {
  margin-top: 10px;
  padding: 14px;
  border-radius: 999px;
  border: none;
  background: #2563eb;
  color: white;
  font-weight: 600;
  cursor: pointer;
}

/* ACTIVE FORM */
.login {
  display: flex;
  opacity: 1;
  transform: translateX(0);
}
.register {
  opacity: 0;
  display: none;
}

.container.active .login {
  display: none;
  opacity: 0;
  transform: translateX(-40px);
}

.container.active .register {
  display: flex;
  opacity: 1;
  transform: translateX(0);
}

/* PANEL SLIDE LOGIC */
.container.active .panel-left {
  transform: translateX(100%);
}

.container.active .panel-right {
  transform: translateX(-100%);
}