* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  background: #e0e5ec;
  font-family: 'Segoe UI', Arial, Helvetica, sans-serif;
  color: #333;
}

.back-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  position: absolute;
  left: 24px;
  top: 24px;
  font-size: 14px;
  font-weight: 600;
  color: #7b4bff;
  background: #e0e5ec;
  padding: 8px 14px;
  border-radius: 20px;
  box-shadow: 4px 4px 8px #b8bec7, -4px -4px 8px #ffffff;
  transition: 0.2s ease;
}

.back-btn:hover {
  box-shadow: 6px 6px 12px #b8bec7, -6px -6px 12px #ffffff;
}

.tool-container {
  max-width: 620px;
  margin: 0 auto;
  padding: 80px 24px 60px;
  position: relative;
}

.tool-header {
  text-align: center;
  margin-bottom: 36px;
}

.tool-header h1 {
  font-size: 30px;
  font-weight: 800;
  color: #7b4bff;
  margin: 0 0 8px;
}

.subtitle {
  font-size: 15px;
  color: #666;
  margin: 0;
  line-height: 1.5;
}

/* Upload box */
.upload-box {
  background: #e0e5ec;
  border-radius: 16px;
  padding: 48px 24px;
  text-align: center;
  cursor: pointer;
  box-shadow: 8px 8px 16px #b8bec7, -8px -8px 16px #ffffff;
  margin-bottom: 24px;
  border: 2px dashed #c5ccd6;
  transition: 0.2s ease;
}

.upload-box:hover {
  border-color: #7b4bff;
  box-shadow: 10px 10px 20px #b8bec7, -10px -10px 20px #ffffff;
}

.upload-box input {
  display: none;
}

.upload-icon {
  width: 72px;
  height: 72px;
  margin: 0 auto 16px;
  background: #e0e5ec;
  border-radius: 16px;
  box-shadow: inset 6px 6px 12px #b8bec7, inset -6px -6px 12px #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
}

.upload-icon img {
  width: 40px;
  opacity: 0.8;
}

.upload-text {
  font-size: 15px;
  color: #666;
  margin: 0;
}

.upload-hint {
  font-size: 13px;
  color: #999;
  margin: 6px 0 0;
}

/* File info */
.file-info {
  background: #e0e5ec;
  padding: 14px 20px;
  border-radius: 10px;
  box-shadow: inset 4px 4px 8px #b8bec7, inset -4px -4px 8px #ffffff;
  margin-bottom: 24px;
  font-size: 14px;
  color: #555;
  display: none;
}

/* Settings */
.settings-box {
  background: #e0e5ec;
  padding: 24px;
  border-radius: 16px;
  box-shadow: inset 6px 6px 12px #b8bec7, inset -6px -6px 12px #ffffff;
  margin-bottom: 24px;
}

.settings-box label {
  display: block;
  margin-bottom: 8px;
  font-size: 13px;
  font-weight: 600;
  color: #555;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.settings-box input,
.settings-box select {
  width: 100%;
  padding: 12px 16px;
  border-radius: 8px;
  border: none;
  background: #e0e5ec;
  box-shadow: inset 4px 4px 8px #b8bec7, inset -4px -4px 8px #ffffff;
  margin-bottom: 20px;
  font-size: 15px;
  color: #333;
  box-sizing: border-box;
  outline: none;
}

.settings-box input:focus,
.settings-box select:focus {
  box-shadow: inset 4px 4px 8px #b8bec7, inset -4px -4px 8px #ffffff, 0 0 0 2px #7b4bff44;
}

.settings-box input:last-child,
.settings-box select:last-child {
  margin-bottom: 0;
}

/* Buttons */
.primary-btn {
  width: 100%;
  padding: 16px;
  background: linear-gradient(135deg, #7b4bff, #9b6bff);
  color: white;
  border: none;
  border-radius: 12px;
  font-size: 17px;
  font-weight: 700;
  cursor: pointer;
  margin-bottom: 24px;
  box-shadow: 6px 6px 12px #b8bec7, -6px -6px 12px #ffffff;
  transition: 0.2s ease;
  letter-spacing: 0.3px;
}

.primary-btn:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 8px 8px 16px #b8bec7, -8px -8px 16px #ffffff;
}

.primary-btn:disabled {
  background: linear-gradient(135deg, #b0a0d8, #c5b8e8);
  cursor: default;
  transform: none;
}

/* Result box */
.result-box {
  background: #e0e5ec;
  padding: 20px;
  border-radius: 12px;
  box-shadow: inset 6px 6px 12px #b8bec7, inset -6px -6px 12px #ffffff;
  display: none;
  font-size: 15px;
  line-height: 1.6;
  color: #444;
}