/* Reset */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Inter", Arial, sans-serif;
}

/* Page layout */
body {
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  background: #f5f7fa;
  color: #333;
}

.container {
  background: #fff;
  padding: 2rem 2.5rem;
  border-radius: 12px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  width: 100%;
  max-width: 400px;
  text-align: center;
}

/* Heading */
h1 {
  font-size: 1.6rem;
  margin-bottom: 1.5rem;
  color: #222;
}

/* Labels */
label {
  display: block;
  font-weight: 500;
  margin-bottom: 0.5rem;
}

/* File input */
input[type="file"] {
  display: block;
  width: 100%;
  border: 2px dashed #cbd5e0;
  border-radius: 8px;
  padding: 1rem;
  background-color: #fafafa;
  cursor: pointer;
  transition: border-color 0.3s ease, background-color 0.3s ease;
}

input[type="file"]:hover {
  border-color: #4f46e5;
  background-color: #f0f0ff;
}

/* Submit button */
input[type="submit"] {
  margin-top: 1.5rem;
  background-color: #4f46e5;
  color: white;
  font-weight: 600;
  border: none;
  border-radius: 8px;
  padding: 0.75rem 1.5rem;
  cursor: pointer;
  transition: background-color 0.3s ease, transform 0.1s ease;
}

input[type="submit"]:hover {
  background-color: #4338ca;
  transform: translateY(-1px);
}

/* Loader overlay */
.loader-overlay {
  display: none;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(3px);
  z-index: 9999;
}

.spinner {
  border: 4px solid #e0e7ff;
  border-top: 4px solid #4f46e5;
  border-radius: 50%;
  width: 48px;
  height: 48px;
  animation: spin 1s linear infinite;
  margin-bottom: 1rem;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.loader-overlay p {
  font-size: 1rem;
  color: #444;
}

/* Responsive */
@media (max-width: 480px) {
  .container {
    padding: 1.5rem;
  }
  h1 {
    font-size: 1.4rem;
  }
}


/* ===== Success Page Styles ===== */
.success-container {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  background: #f5f7fa;
}

.success-card {
  background: #fff;
  padding: 2.5rem 3rem;
  border-radius: 16px;
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.1);
  text-align: center;
  max-width: 420px;
  width: 100%;
  animation: fadeIn 0.5s ease-in-out;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

.checkmark {
  width: 64px;
  height: 64px;
  line-height: 64px;
  border-radius: 50%;
  background-color: #4ade80;
  color: white;
  font-size: 2rem;
  margin: 0 auto 1.2rem;
}

.success-card h2 {
  font-size: 1.6rem;
  color: #222;
  margin-bottom: 0.5rem;
}

.success-card p {
  font-size: 1rem;
  color: #555;
  margin-bottom: 0.5rem;
}

/* Download button */
.download-btn {
  display: inline-block;
  background-color: #4f46e5;
  color: #fff;
  text-decoration: none;
  font-weight: 600;
  padding: 0.75rem 1.5rem;
  border-radius: 8px;
  margin-top: 1.2rem;
  transition: background-color 0.3s ease, transform 0.1s ease;
}

.download-btn:hover {
  background-color: #4338ca;
  transform: translateY(-1px);
}

/* Back link */
.back-link {
  display: block;
  margin-top: 1rem;
  font-size: 0.95rem;
  color: #555;
  text-decoration: none;
  transition: color 0.2s ease;
}

.back-link:hover {
  color: #111;
}