*, *::before, *::after {
  box-sizing: border-box;
}

body {
  font-family: system-ui, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
  margin: 0;
  background: #f8fafc;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  padding: 40px 20px;
}

.pricing-container {
  width: 100%;
  max-width: 800px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.billing-toggle {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 50px;
}

.billing-label {
  font-weight: 600;
  color: #334155;
  display: flex;
  align-items: center;
  gap: 8px;
}

.discount-badge {
  background: #dcfce7;
  color: #166534;
  padding: 4px 8px;
  border-radius: 12px;
  font-size: 0.75rem;
}

.switch-box {
  position: relative;
  display: inline-block;
  width: 60px;
  height: 32px;
}

.billing-cb {
  display: none;
}

.switch-slider {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background-color: #cbd5e1;
  border-radius: 32px;
  cursor: pointer;
  transition: 0.3s;
}

.switch-slider::before {
  position: absolute;
  content: "";
  height: 24px;
  width: 24px;
  left: 4px;
  bottom: 4px;
  background-color: #ffffff;
  border-radius: 50%;
  transition: 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  box-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.billing-cb:checked + .switch-slider {
  background-color: #3b82f6;
}

.billing-cb:checked + .switch-slider::before {
  transform: translateX(28px);
}

.pricing-cards {
  display: flex;
  gap: 24px;
  width: 100%;
  justify-content: center;
  flex-wrap: wrap;
}

.plan-card {
  background: #ffffff;
  border: 1px solid #e2e8f0;
  border-radius: 24px;
  padding: 40px 30px;
  width: 100%;
  max-width: 320px;
  text-align: center;
  box-shadow: 0 10px 20px -5px rgba(0,0,0,0.05);
  position: relative;
}

.plan-card.popular {
  border: 2px solid #3b82f6;
  transform: translateY(-10px);
  box-shadow: 0 20px 40px -10px rgba(59, 130, 246, 0.2);
}

.popular-tag {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: #3b82f6;
  color: #ffffff;
  font-size: 0.8rem;
  font-weight: 700;
  padding: 4px 16px;
  border-radius: 20px;
  text-transform: uppercase;
}

.plan-card h3 {
  margin: 0 0 20px 0;
  color: #0f172a;
  font-size: 1.25rem;
}

.price-display {
  display: flex;
  justify-content: center;
  align-items: baseline;
  margin-bottom: 30px;
}

.currency {
  font-size: 1.5rem;
  font-weight: 700;
  color: #0f172a;
}

.price-val {
  font-size: 4rem;
  font-weight: 800;
  color: #0f172a;
  letter-spacing: -2px;
  /* Add monospace font to prevent layout shifting during number animation */
  font-variant-numeric: tabular-nums;
}

.period {
  font-size: 1rem;
  color: #64748b;
  font-weight: 500;
}

.plan-btn {
  width: 100%;
  background: #f1f5f9;
  color: #0f172a;
  border: none;
  padding: 14px;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  transition: background 0.2s;
}

.plan-btn:hover { background: #e2e8f0; }

.plan-btn.primary {
  background: #3b82f6;
  color: #ffffff;
}

.plan-btn.primary:hover { background: #2563eb; }

const toggle = document.getElementById("billing-checkbox");
const priceBasic = document.getElementById("price-basic");
const pricePro = document.getElementById("price-pro");

/* Safely animate number counting without external libraries */
function animateValue(obj, start, end, duration) {
  let startTimestamp = null;
  const step = function(timestamp) {
    if (!startTimestamp) startTimestamp = timestamp;
    const progress = Math.min((timestamp - startTimestamp) / duration, 1);
    
    const currentVal = Math.floor(progress * (end - start) + start);
    obj.innerText = currentVal;
    
    if (progress < 1) {
      window.requestAnimationFrame(step);
    } else {
      obj.innerText = end;
    }
  };
  window.requestAnimationFrame(step);
}

toggle.addEventListener("change", function(e) {
  const isYearly = e.target.checked;
  
  const basicStart = parseInt(priceBasic.innerText);
  const basicEnd = isYearly ? parseInt(priceBasic.getAttribute("data-yearly")) : parseInt(priceBasic.getAttribute("data-monthly"));
  
  const proStart = parseInt(pricePro.innerText);
  const proEnd = isYearly ? parseInt(pricePro.getAttribute("data-yearly")) : parseInt(pricePro.getAttribute("data-monthly"));
  
  animateValue(priceBasic, basicStart, basicEnd, 400);
  animateValue(pricePro, proStart, proEnd, 400);
});