:root {
    --primary-color: #007AFF;
    --background-color: #F5F5F7;
    --input-background: #FFFFFF;
    --text-color: #1D1D1F;
    --border-radius: 10px;
    --spacing: 20px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.5;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing);
}

h1 {
    font-size: 24px;
    margin-bottom: var(--spacing);
    color: #1D1D1F;
}

h2 {
    font-size: 20px;
    margin-bottom: var(--spacing);
}

.input-section {
    background: var(--input-background);
    padding: var(--spacing);
    border-radius: var(--border-radius);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.input-group {
    margin-bottom: 15px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
}

input {
    width: 100%;
    padding: 10px;
    border: 1px solid #D1D1D6;
    border-radius: var(--border-radius);
    font-size: 16px;
    transition: border-color 0.3s;
}

input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.controls {
    display: flex;
    gap: 10px;
    margin-top: var(--spacing);
}

.button {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 16px;
    transition: opacity 0.3s;
}

.button:hover {
    opacity: 0.9;
}

.preview-section {
    background: var(--input-background);
    padding: var(--spacing);
    border-radius: var(--border-radius);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.signature-preview {
    padding: var(--spacing);
    border-radius: var(--border-radius);
    transition: all 0.3s ease;
    border: 1px solid #D1D1D6;
    min-height: 200px;
    position: relative;
}

#signatureContent {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.copy-overlay {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary-color);
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.copy-overlay.show {
    opacity: 1;
    visibility: visible;
}

.copy-overlay svg {
    stroke-width: 3;
}

.button-success {
    background-color: #34C759 !important;
}

.button-error {
    background-color: #FF3B30 !important;
}

.button {
    transition: background-color 0.3s ease;
}

@media (max-width: 768px) {
    .container {
        grid-template-columns: 1fr;
    }
}