:root {
    --primary-color: #2D545E;
    --secondary-color: #E6E9F0;
    --accent-color: #5F9EA0;
    --text-color: #333;
    --text-light: #666;
    --bg-light: #F0F4F8;
    --card-bg: #FFFFFF;
    --border-radius: 12px;
    --box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
}

body {
    font-family: 'Roboto', sans-serif;
    background-color: var(--bg-light);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    color: var(--text-color);
    line-height: 1.6;
    padding: 20px; /* Added padding for mobile optimization */
    box-sizing: border-box;
}

.container {
    width: 100%; /* Changed from 95% to 100% for better mobile fit */
    max-width: 800px;
    text-align: center;
}

header {
    margin-bottom: 30px;
}

.logo {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin: 0;
    letter-spacing: -1px;
}

header p {
    color: var(--text-light);
    font-size: 1.1rem;
}

.card {
    background-color: var(--card-bg);
    padding: 35px;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    margin-bottom: 25px;
    text-align: left;
    transition: all 0.4s ease;
}

.drop-area {
    border: 2px dashed var(--accent-color);
    border-radius: var(--border-radius);
    padding: 30px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-bottom: 20px;
}

.drop-area:hover,
.drop-area.highlight {
    background-color: var(--secondary-color);
    border-color: var(--primary-color);
}

.drop-area p {
    margin: 0 0 10px 0;
    color: var(--primary-color);
    font-weight: 500;
}

.file-name {
    color: var(--text-light);
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
    display: block;
    margin-top: 5px;
}

.input-group {
    margin-bottom: 20px;
}

.input-field {
    width: 100%;
    padding: 12px;
    border-radius: 8px;
    border: 1px solid #ccc;
    font-size: 1rem;
    box-sizing: border-box;
    transition: border-color 0.3s ease;
    background-color: #fff; /* Added background for consistency */
    -webkit-appearance: none; /* Remove default select styles on mobile */
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%23333' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 10px center;
    padding-right: 30px;
}

.input-field:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(45, 84, 94, 0.2);
}

.btn {
    padding: 12px 25px;
    border-radius: 8px;
    border: none;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
    width: 100%;
    margin-top: 10px;
}

.btn-primary:disabled {
    background-color: #99a2ab;
    cursor: not-allowed;
}

.btn-primary:hover:not(:disabled) {
    background-color: #21434d;
    transform: translateY(-2px);
}

.output-header {
    border-bottom: 2px solid var(--secondary-color);
    padding-bottom: 10px;
    margin-bottom: 15px;
}

.output-header h2 {
    color: var(--primary-color);
    font-size: 1.5rem;
    margin: 0;
}

.data-list {
    list-style: none;
    padding: 0;
    margin: 0;
    max-height: 300px;
    overflow-y: auto;
    border: 1px solid var(--secondary-color);
    border-radius: 8px;
    background-color: var(--bg-light);
}

.data-list li {
    padding: 12px 15px;
    border-bottom: 1px solid var(--secondary-color);
    word-wrap: break-word;
}

.data-list li:last-child {
    border-bottom: none;
}

.download-options {
    display: flex;
    justify-content: flex-end;
    gap: 15px;
    margin-top: 25px;
}

.btn-secondary {
    background-color: var(--accent-color);
    color: white;
}

.btn-secondary:hover {
    background-color: #498b8d;
}

.hidden {
    display: none;
}