* {
  box-sizing: border-box;
  padding: 0;
  margin: 0;
}

:root {
  --bg-original: #8f9ba9;
  --bg-header: #a1bdfb 0%, #3b5998 50%, #102142 100%;
  --text: #333333;
  --text-header: #ffffff;
  --bg-info: #dce5ee;
  --border-area: grey;
  --decor-left: 5px solid #3b5998;
  --btn: #a1bdfb 0%, #3b5998 50%, #102142 100%;
  --bg-drag: #e3f2fd;
  --btn-download: #e1e3e4;
  --btn-reset: #3c454c;
  --bg-footer: #a1bdfb 0%, #3b5998 50%, #102142 100%;
  --text-footer: #ffffff;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
  --block-padding: 25px;
  --block-margin: 25px;
}

body {
  height: 100%;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg-original);
  padding: 20px;
}

.container {
  max-width: 800px;
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  background: #ffffff;
  border-radius: 15px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
  overflow: hidden;
  margin: 0 auto;
}

header {
  background: linear-gradient(135deg, var(--bg-header));
  color: var(--text-header);
  text-align: center;
  padding: var(--block-padding);
  margin-bottom: var(--block-margin);
}

h1 {
  font-size: 2.2rem;
  margin-bottom: 10px;
}

.subtitle {
  font-size: 1.1rem;
  opacity: 0.9;
}

main {
  display: flex;
  flex-direction: column;
  flex: 1;
  /* justify-content: space-between; */
  padding: 0 30px;
}

.upload-area {
  text-align: center;
  background: var(--bg-info);
  border: 2.3px dashed var(--border-area);
  border-radius: 10px;
  transition: all 0.3s ease;
  padding: var(--block-padding);
  margin-bottom: var(--block-margin);
}

.upload-area.drag {
  background: var(--bg-drag);
  border-color: #2196f3;
  transform: scale(1.02);
}

.upload-or {
  margin-bottom: 5px;
}

.upload-info {
  font-size: 0.8rem;
}

.file-input {
  display: none;
}

.btn {
  display: inline-block;
  font-size: 1rem;
  text-decoration: none;
  background: linear-gradient(135deg, var(--btn));
  color: white;
  border: none;
  border-radius: 10px;
  /* outline: 1px solid gray; */
  cursor: pointer;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  padding: 12px 25px;
}

.btn:hover {
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
  transform: translateY(-2px);
}

.btn:disabled {
  background: #cccccc;
  cursor: not-allowed;
  box-shadow: none;
  transform: none;
}

.btn-download {
  background: var(--btn-download);
  color: var(--text);
}

.btn-area {
  margin-bottom: 10px;
}

.btn-reset {
  background: var(--btn-reset);
  outline: var(--btn-reset);
}

.file-info {
  background: var(--bg-info);
  border-radius: 8px;
  border-left: var(--decor-left);
  padding: 15px;
  margin-bottom: var(--block-margin);
}

.controls {
  display: flex;
  gap: 15px;
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: var(--block-margin);
}

.log-area {
  height: 100%;
  min-height: 150px;
  font-size: 0.9rem;
  font-family: 'Courier New', monospace;
  color: #edecec;
  background: #1e1e1e;
  border-radius: 8px;
  overflow-y: auto;
  white-space: pre-wrap;
  padding: var(--block-padding);
  margin-bottom: var(--block-margin);
}

.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 15px;
  margin-bottom: var(--block-margin);
}

.feature {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  text-align: center;
  background: var(--bg-info);
  border-radius: 8px;
  border-left: var(--decor-left);
  padding: var(--block-padding);
}

footer {
  font-size: 0.9rem;
  color: var(--text-footer);
  text-align: center;
  background: linear-gradient(135deg, var(--bg-footer));
  padding: 20px;
  margin-top: auto;
}

@media (max-width: 600px) {
  .container {
    border-radius: 10px;
  }

  header {
    padding: 20px;
  }

  h1 {
    font-size: 1.8rem;
  }

  main {
    padding: 20px;
  }

  .controls {
    flex-direction: column;
    align-items: center;
  }

  .btn {
    width: 100%;
    max-width: 250px;
  }
}