:root {
    --bg-color: #f8f9fa;
    --card-bg: #ffffff;
    --text-color: #212529;
    --text-muted: #6c757d;
    --border-color: #dee2e6;
    --primary-color: #0d6efd;
    --primary-hover: #0b5ed7;
    --secondary-color: #6c757d;
    --secondary-hover: #5c636a;
    --input-bg: #ffffff;
    --input-border: #ced4da;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --radius: 0.5rem;
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

[data-theme="dark"] {
    --bg-color: #121212;
    --card-bg: #1e1e1e;
    --text-color: #e0e0e0;
    --text-muted: #a0a0a0;
    --border-color: #333333;
    --primary-color: #3b82f6;
    --primary-hover: #2563eb;
    --secondary-color: #4b5563;
    --secondary-hover: #374151;
    --input-bg: #2d2d2d;
    --input-border: #404040;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.5), 0 2px 4px -1px rgba(0, 0, 0, 0.3);
}

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

body {
    font-family: var(--font-family);
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.5;
    transition: background-color 0.3s, color 0.3s;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.container {
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* Header */
.app-header {
    padding: 1rem 0;
    background-color: var(--card-bg);
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 2rem;
}

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

.app-header h1 {
    font-size: 1.5rem;
    font-weight: 700;
}

/* Theme Toggle */
.icon-button {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--text-color);
    padding: 0.5rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color 0.2s;
}

.icon-button:hover {
    background-color: rgba(128, 128, 128, 0.1);
}

.sun-icon {
    display: none;
}

[data-theme="dark"] .sun-icon {
    display: block;
}

[data-theme="dark"] .moon-icon {
    display: none;
}

/* Main Content */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.card {
    background-color: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 2rem;
    width: 100%;
    border: 1px solid var(--border-color);
}

.input-group {
    margin-bottom: 1.5rem;
    display: flex;
    flex-direction: column;
}

.input-group label {
    font-weight: 500;
    margin-bottom: 0.5rem;
    font-size: 0.95rem;
}

textarea, input[type="text"] {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--input-border);
    border-radius: var(--radius);
    background-color: var(--input-bg);
    color: var(--text-color);
    font-family: inherit;
    font-size: 1rem;
    transition: border-color 0.2s, box-shadow 0.2s;
}

textarea:focus, input[type="text"]:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(13, 110, 253, 0.25);
}

[data-theme="dark"] textarea:focus, [data-theme="dark"] input[type="text"]:focus {
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.25);
}

.helper-text {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: 0.5rem;
}

.row {
    display: flex;
    gap: 1.5rem;
}

.row .input-group {
    flex: 1;
}

/* Actions */
.actions {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
    flex: 1;
}

.btn:active {
    transform: translateY(1px);
}

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

.btn-primary:hover {
    background-color: var(--primary-hover);
}

.btn-primary:disabled {
    opacity: 0.7;
    cursor: not-allowed;
}

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

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

/* Status Message */
.status-message {
    margin-top: 1.5rem;
    padding: 1rem;
    border-radius: var(--radius);
    display: none;
    font-size: 0.95rem;
}

.status-message.success {
    display: block;
    background-color: rgba(25, 135, 84, 0.1);
    color: #198754;
    border: 1px solid rgba(25, 135, 84, 0.2);
}

[data-theme="dark"] .status-message.success {
    background-color: rgba(34, 197, 94, 0.1);
    color: #4ade80;
    border: 1px solid rgba(34, 197, 94, 0.2);
}

.status-message.error {
    display: block;
    background-color: rgba(220, 53, 69, 0.1);
    color: #dc3545;
    border: 1px solid rgba(220, 53, 69, 0.2);
}

[data-theme="dark"] .status-message.error {
    background-color: rgba(239, 68, 68, 0.1);
    color: #f87171;
    border: 1px solid rgba(239, 68, 68, 0.2);
}

/* Footer */
.app-footer {
    margin-top: 3rem;
    padding: 1.5rem 0;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 600px) {
    .row {
        flex-direction: column;
        gap: 0;
    }
    
    .card {
        padding: 1.5rem;
        border-radius: 0;
        border-left: none;
        border-right: none;
        box-shadow: none;
    }

    .container {
        padding: 0;
    }
    
    .header-content, .app-footer .container {
        padding: 0 1rem;
    }
    
    .main-content {
        width: 100%;
    }
}