:root {
    --primary-color: #007bff;
    --secondary-color: #125eae;
    --error-color: #c60000;
    --success-color: #4CAF50;
    --lighter-gray: #dddddd;
    --light-gray: #888888;
    --dark-gray: #222222;
    --bg-color: #f0f0f0;
    --font-family: 'Roboto', sans-serif;
    --base-font-size: 1em;
    --line-height: 1.4;
    --hero-font-size: 2.8em;
    --hero-line-height: 1.6;
    --hero-letter-spacing: 0.05em;
    --button-padding: 18px 24px;
    --button-border-radius: 4px;
    --link-font-color: #666666;
    --link-hover-color: #202020;
      /* Select Dropdown */
    --select-container-font-color: #202020;
    --select-container-bg: linear-gradient(to bottom, #f9f9f9 0%, #e8e8e8 100%);
    --select-option-font-color: #202020;
    --select-option-bg: #ffffff;
    --select-box-shadow: 0px 1px 3px 0px rgba(0, 0, 0, 0.2), 0px 1px 1px 0px rgba(0, 0, 0, 0.08), 0px 2px 1px -1px rgba(0, 0, 0, 0.04);
    --select-arrow: #666666;
}

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

body {
    font-family: var(--font-family);
    margin: 0;
    padding: 15px;
    color: var(--dark-gray);
    background-color: var(--bg-color);
    font-size: var(--base-font-size);
    line-height: var(--line-height);
}

header {
    display: flex;
    align-items: center;
    justify-content: space-between;
  }
  

  footer {
    margin-top: auto;
    padding: 15px;
    text-align: center;
    color: var(--light-gray);
  }
  
  footer p {
    font-size: var(--font-size-small);
    margin: 10px;
    line-height: var(--line-height-normal);
  }

.hero {
    padding: 20px 20px;
    text-align: center;
}

.hero .branding {
    font-size: var(--hero-font-size);
    margin-bottom: 15px;
    margin-top: 5px;
    letter-spacing: -0.03em;
}

.hero p {
    font-size: 1.25em;
    max-width: 800px;
    margin: 0 auto;
    letter-spacing: var(--hero-letter-spacing);
    line-height: var(--hero-line-height);
}

.wrapper {
    margin: 0 auto;
    max-width: 960px;
}

h1 {
    font-size: 2em;
    line-height: 1.2em;
}

p {
    margin: 10px 5px;
}

a,
a:link,
a:active,
a:visited {
  color: var(--link-font-color);
  text-decoration: none;
}

a:hover {
  color: var(--link-hover-color);
}

.bold {
    font-weight: 600;
}

.light-gray {
    color: var(--light-gray);
}

.blue {
    color: var(--primary-color);
}

.hidden {
    display: none;
}

.align-center {
    text-align: center;
}

#file-input {
    display: none;
}

.button, button, button[type="submit"] {
    margin: 8px 4px 8px 0;
    font-weight: 600;
    text-align: center;
    display: inline-block;
    background-color: var(--primary-color);
    color: #fff;
    padding: var(--button-padding);
    border: none;
    border-radius: var(--button-border-radius);
    cursor: pointer;
    font-size: 1em;
}

.button:hover, button:hover, #file-upload-label:hover {
    background-color: var(--secondary-color);
    color: var(--lighter-gray);;
}

.button:active, button:active {
    background-color: var(--primary-color);
    box-shadow: inset 0 4px 6px rgba(0, 0, 0, 0.125);
}

.button[disabled], button[disabled], button[disabled]:hover {
    background-color: var(--lighter-gray);;
    color: #ffffff;
    opacity: 0.65;
    cursor: not-allowed;
}

.btn-outline, .btn-outline:hover, .btn-outline:hover {
    background: none;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
    padding: 12px 20px;
}

#progress-container {
    display: none;
    margin-top: 20px;
}

#progress-bar {
    width: 0;
    height: 20px;
    background-color: var(--primary-color);
    transition: width 0.3s;
}

#drop-area {
    margin: 8px 4px 8px 0;
    border: 1px dashed var(--light-gray);
    padding: 30px;
    text-align: center;
    margin-bottom: 20px;
    color: var(--light-gray);
}

#drop-area.drag {
    border-color: var(--error-color);
}

#file-list {
    margin: 8px 4px 8px 0;
    color: var(--light-gray);
    display: flex;
    justify-content: center;
}

#selected-files-list {
    margin: 0;
    list-style: none;
    padding: 0;
    display: flex;
    flex-wrap: wrap;
    gap: 5px;
}

#selected-files-list li {
    background-color: var(--lighter-gray);
    display: flex;
    align-items: center;
    justify-content: flex-start;
    padding: 10px;
    word-break: break-word;
}

#selected-files-list li span {
    font-weight: bold;
    margin-right: auto;
    padding-right: 5px;
}

#file-upload-label {
    margin: 8px 4px 8px 0;
    font-weight: 600;
    text-align: center;
    display: block;
    background-color: var(--primary-color);
    color: #ffffff;
    padding: var(--button-padding);
    border: none;
    border-radius: 4px;
    cursor: pointer;
}


#error-message {
    margin: 8px 4px 8px 0;
    font-weight: 600;
    text-align: center;
    background-color: var(--error-color);
    color: #ffffff;
    padding: var(--button-padding);
    display: none;
    border-radius: 4px;
}

#download-link {
    margin: 8px 4px 8px 0;
    font-weight: 600;
    text-align: center;
    display: block;
    background-color: none;
    color: var(--primary-color);
    padding: var(--button-padding);
    cursor: pointer;
    border: 1px solid var(--primary-color);
    border-radius: 4px;
}

#success-message {
    margin: 8px 4px 8px 0;
    font-weight: 600;
    text-align: center;
    background-color: var(--success-color);
    color: #ffffff;
    padding: var(--button-padding);
    display: none;
    border-radius: 4px;
}

.small {
    font-size: 0.8em;
    line-height: 1.3em;
}

/* select dropdown */

.select-group {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
  }
  
  .select-container {
    flex-basis: 100%;
    margin-bottom: 12px;
  }
  
  .select-container {
    margin: 12px 0;
    position: relative;
    display: inline-block;
    background: var(--select-container-bg);
    border-radius: 3px;
    overflow: hidden;
    box-shadow: var(--select-box-shadow);
  }
  
  .select-container::after {
    content: "\25BC";
    position: absolute;
    top: 50%;
    right: 12px;
    transform: translateY(-50%);
    pointer-events: none;
    font-size: 14px;
    color: var(--select-arrow);
    transition: transform 0.3s ease-in-out;
  }
  
  .select-container.open::after {
    transform: translateY(-50%) rotate(-90deg);
  }
  
  .select-container select {
    color: var(--select-container-font-color);
    width: 100%;
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    background: transparent;
    padding: 14px 30px 14px 16px;
    border: none;
    font-size: 14px;
  }
  
  .select-container select::-ms-expand {
    display: none;
  }

  .select-container select option,
  .select-container select option:hover,
  .select-container select option:checked,
  .select-container select option:focus {
    background: var(--select-option-bg);
    color: var(--select-option-font-color);
    padding: 10px;
  }

  .spinner {
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top: 4px solid #007bff;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 999;
    display: none;
  }
  
  @keyframes spin {
    0% { transform: translate(-50%, -50%) rotate(0deg); }
    100% { transform: translate(-50%, -50%) rotate(360deg); }
  }