:root {
    --bg-main: #ffffff;
    --bg-card: #fafbff;
    --border-subtle: #e0e8f0;
    --text-primary: #1a1a1a;
    --text-secondary: #6b7280;
    --primary: #2f284d;
    --accent: #f87d00;
}

body.dark-mode {
    --bg-main: #181824;
    --bg-card: #232336;
    --border-subtle: #35354a;
    --text-primary: #f3f3fa;
    --text-secondary: #b0b3c7;
    --primary: #b7aaff;
    --accent: #ffb86b;
}

.tool-container {
    background: var(--bg-card);
    padding: 0; 
}

.upload-zone {
    border: 2px dashed var(--border-subtle);
    background: var(--bg-main);
    color: var(--text-primary);
    padding: 60px 40px;
    text-align: center;
    border-radius: 16px;
    transition: all 0.3s ease;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
}

.upload-zone:hover {
    border-color: var(--primary);
    background: var(--bg-card);
    transform: translateY(-2px);
}

.upload-zone i {
    color: var(--primary);
    font-size: 3rem;
    margin-bottom: 10px;
}

.upload-zone p {
    color: var(--text-secondary);
    font-weight: 500;
    margin: 0;
}

.btn-tool-primary {
    background-color: var(--primary);
    color: #ffffff;
    border: none;
    padding: 12px 25px;
    border-radius: 8px;
    font-weight: 600;
    transition: 0.3s;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-size: 14px;
}

.btn-tool-primary:hover {
    background-color: var(--primary-light);
    color: #fff;
    box-shadow: 0 5px 15px rgba(47, 40, 77, 0.2);
}

#result-area {
    margin-top: 30px;
    animation: fadeIn 0.5s ease;
}

#base64Output {
    background: #f8f9fa;
    border: 1px solid #dee2e6;
    border-radius: 10px;
    font-family: 'Courier New', Courier, monospace;
    font-size: 13px;
    padding: 15px;
    color: #333;
    resize: none;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}