:root {
  --bg: #121212;
  --card-bg: #1c1c1e;
  --text: #e0e0e0;
  --primary-start: rgb(22, 119, 106);
  --primary-end: #0b6478;
  --input-bg: #252525;
  --input-border: #444;
  --input-focus-border: #0b6478;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: 'Poppins', sans-serif;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 3rem 1rem 4rem;
  overflow-x: hidden;
}

@keyframes fadeSlideDown {
  0% {
    opacity: 0;
    transform: translateY(-20px);
  }
  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

h1 {
  margin-bottom: 1.8rem;
  font-weight: 700;
  font-size: 2.8rem;
  letter-spacing: 0.04em;
  user-select: none;
  animation: fadeSlideDown 0.8s ease forwards;
}

.summary {
  color: #888;
  font-size: 1rem;
  margin-top: -0.5rem;
  margin-bottom: 2rem;
  text-align: center;
  user-select: none;
  font-weight: 500;
  max-width: 360px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.4;
}

.card {
  background: var(--card-bg);
  border-radius: 20px;
  padding: 2.5rem 3rem;
  width: 100%;
  max-width: 420px;
  box-shadow: 0 15px 30px rgba(0,0,0,0.6);
  animation: fadeSlideDown 1s ease forwards;
  animation-delay: 0.4s;
  animation-fill-mode: both;
  animation-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
}

label {
  display: block;
  text-align: center;
  font-weight: 600;
  margin-bottom: 1rem;
  user-select: none;
  font-size: 1.1rem;
  color: #aaa;
  cursor: pointer;
  position: relative;
  padding-bottom: 0.3rem;
}

label:hover {
  color: var(--primary-end);
}

input[type="file"] {
  display: none;
}

.file-label {
  background: var(--input-bg);
  border: 2.5px solid var(--input-border);
  border-radius: 50px;
  padding: 1rem 1.2rem;
  width: 100%;
  font-size: 1.15rem;
  color: var(--text);
  text-align: center;
  cursor: pointer;
  user-select: none;
  transition:
    border-color 0.4s ease,
    background-color 0.4s ease,
    color 0.4s ease;
}

.file-label:hover {
  border-color: var(--input-focus-border);
  background-color: #282828;
  color: var(--primary-end);
}

.file-label:active {
  background-color: #1a1a1a;
}

#uploadBtn {
  margin-bottom: 2rem;
  display: block;
}

button {
  background: linear-gradient(135deg, var(--primary-start), var(--primary-end));
  color: var(--bg);
  border: none;
  padding: 1rem 0;
  width: 100%;
  border-radius: 50px;
  cursor: pointer;
  font-size: 1.2rem;
  font-weight: 700;
  user-select: none;
  outline: none;
  transition:
    background-color 0.3s ease,
    transform 0.2s ease;
  margin-bottom: 1.4rem;
  letter-spacing: 0.04em;
  box-shadow: none;
}

button:hover:not(:disabled) {
  background: linear-gradient(135deg, var(--primary-end), var(--primary-start));
  transform: scale(1.05);
  box-shadow: none;
}

button:active:not(:disabled) {
  transform: scale(0.95);
  box-shadow: none;
}

button:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  background: #444;
  color: #999;
  box-shadow: none;
}

#status {
  margin-top: 0;
  font-size: 1rem;
  color: var(--primary-end);
  min-height: 1.4rem;
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 0.4s ease, transform 0.4s ease;
  user-select: none;
}

#status.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Footer text */
.footer-note {
  position: fixed;
  bottom: 10px;
  left: 10px;
  font-size: 0.8rem;
  color: #666;
  user-select: none;
  font-family: 'Poppins', sans-serif;
  pointer-events: none;
  opacity: 0.7;
  z-index: 999;
}

@media (max-width: 450px) {
  .card {
    padding: 2rem 2rem;
  }
  button {
    font-size: 1.1rem;
    padding: 0.85rem 0;
  }
  h1 {
    font-size: 2rem;
    margin-bottom: 1rem;
  }
}