styles.css

:root {
    /* Colors */
    --primary-color: #3498db;
    --secondary-color: #2c3e50;
    --background-color: #ecf0f1;
    --text-color: #34495e;
    --error-color: #dc3545;
    --success-color: #28a745;
    --warning-color: #ffc107;
    --border-color: #ddd;
    
    /* Typography */
    --font-family: 'Roboto', -apple-system, BlinkMacSystemFont, 'Segoe UI', Oxygen, Ubuntu, sans-serif;
    --font-size-base: 16px;
    --line-height-base: 1.6;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    
    /* Border Radius */
    --border-radius-sm: 4px;
    --border-radius-md: 8px;
    --border-radius-lg: 12px;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    
    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 8px 16px rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] {
    --primary-color: #4fc3f7;
    --secondary-color: #ecf0f1;
    --background-color: #1a1a1a;
    --text-color: #ecf0f1;
    --border-color: #2c3e50;
    --error-color: #ff6b6b;
    --success-color: #51cf66;
    --warning-color: #ffd43b;
}

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

html {
    font-size: var(--font-size-base);
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: var(--line-height-base);
    transition: background-color var(--transition-normal), color var(--transition-normal);
}

/* Layout */
.container {
    max-width: 800px;
    margin: 0 auto;
    padding: var(--spacing-xl);
}

/* Header */
header {
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

h1 {
    color: var(--primary-color);
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
    transition: color var(--transition-normal);
}

/* Main Content */
main {
    background-color: white;
    padding: var(--spacing-xl);
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-md);
    transition: background-color var(--transition-normal), box-shadow var(--transition-normal);
}

[data-theme="dark"] main {
    background-color: #2c2c2c;
}

/* Form Elements */
.input-group {
    margin-bottom: var(--spacing-lg);
}

label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-weight: 500;
}

textarea,
input[type="password"] {
    width: 100%;
    padding: var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    font-size: 1rem;
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
    background-color: inherit;
    color: inherit;
}

textarea {
    height: 150px;
    resize: vertical;
}

textarea:focus,
input[type="password"]:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: var(--spacing-md) var(--spacing-lg);
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: var(--border-radius-sm);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: background-color var(--transition-fast), transform var(--transition-fast);
}

.btn:hover {
    background-color: #2980b9;
    transform: translateY(-1px);
}

.btn:active {
    transform: translateY(0);
}

.btn:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.4);
}

.btn-green {
    background-color: var(--success-color);
}

.btn-green:hover {
    background-color: #218838;
}

/* Progress Bar */
.progress-container {
    margin: var(--spacing-lg) 0;
}

.progress-bar {
    height: 10px;
    background-color: var(--border-color);
    border-radius: 5px;
    overflow: hidden;
}

.progress-bar-inner {
    width: 0;
    height: 100%;
    background-color: var(--primary-color);
    transition: width var(--transition-normal);
}

/* Results */
.result {
    margin: var(--spacing-lg) 0;
    text-align: center;
    font-size: 1.2rem;
    font-weight: 500;
}

/* Table Styles */
.connections-table {
    margin-top: var(--spacing-lg);
    overflow-x: auto;
    border-radius: var(--border-radius-sm);
}

.connections-table table {
    width: 100%;
    border-collapse: collapse;
    min-width: 600px;
}

.connections-table th,
.connections-table td {
    padding: var(--spacing-md);
    text-align: left;
    border: 1px solid var(--border-color);
}

.connections-table th {
    background-color: var(--primary-color);
    color: white;
    font-weight: 500;
    position: relative;
    cursor: pointer;
    user-select: none;
}

.connections-table tr:nth-child(even) {
    background-color: rgba(0, 0, 0, 0.02);
}

[data-theme="dark"] .connections-table tr:nth-child(even) {
    background-color: rgba(255, 255, 255, 0.02);
}

/* Error Messages */
.failed-usernames {
    margin-top: var(--spacing-lg);
    padding: var(--spacing-md);
    background-color: rgba(220, 53, 69, 0.1);
    border: 1px solid var(--error-color);
    border-radius: var(--border-radius-sm);
    color: var(--error-color);
}

.failed-usernames h3 {
    margin-bottom: var(--spacing-sm);
}

.failed-usernames ul {
    list-style-type: none;
    padding-left: var(--spacing-md);
}

/* Theme Switch */
.theme-switch-wrapper {
    display: flex;
    align-items: center;
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    font-size: 0.9rem;
}

.theme-switch {
    display: inline-block;
    position: relative;
    width: 60px;
    height: 34px;
    margin-left: var(--spacing-sm);
}

.theme-switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #ccc;
    transition: var(--transition-normal);
}

.slider:before {
    position: absolute;
    content: "";
    height: 26px;
    width: 26px;
    left: 4px;
    bottom: 4px;
    background-color: white;
    transition: var(--transition-normal);
}

input:checked + .slider {
    background-color: var(--primary-color);
}

input:focus + .slider {
    box-shadow: 0 0 1px var(--primary-color);
}

input:checked + .slider:before {
    transform: translateX(26px);
}

.slider.round {
    border-radius: 34px;
}

.slider.round:before {
    border-radius: 50%;
}

/* Responsive Design */
@media (max-width: 600px) {
    :root {
        --font-size-base: 14px;
    }

    .container {
        padding: var(--spacing-md);
    }

    main {
        padding: var(--spacing-md);
    }

    h1 {
        font-size: 2rem;
    }

    .theme-switch-wrapper {
        position: relative;
        justify-content: flex-end;
        margin-bottom: var(--spacing-md);
    }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    * {
        transition: none !important;
    }
}

/* Focus Styles */
:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* Print Styles */
@media print {
    .theme-switch-wrapper,
    .btn {
        display: none !important;
    }

    body {
        background: white;
    }

    main {
        box-shadow: none;
    }

    .connections-table th {
        background-color: #f8f9fa !important;
        color: black !important;
    }
}