:root {
    --primary-color: #00a8cc;
    --primary-hover: #008ba8;
    --secondary-color: #e0f7fa;
    --text-color: #333;
    --bg-color: #f4f7f6;
    --card-bg: #ffffff;
    --error-color: #e74c3c;
    --success-color: #2ecc71;
    --font-family: 'Open Sans', sans-serif;
    --transition-speed: 0.3s;
}

* {
    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: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header */
header {
    background-color: var(--card-bg);
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    padding: 1rem 0;
    text-align: center;
}

.logo {
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--primary-color);
    text-decoration: none;
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* Main Content */
main {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 2rem 1rem;
}

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

.survey-card {
    background: var(--card-bg);
    border-radius: 12px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.05);
    padding: 2.5rem;
    overflow: hidden;
    position: relative;
}

/* Progress Bar */
.progress-container {
    margin-bottom: 2rem;
}

.progress-label {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
    color: #666;
    font-weight: 600;
}

.progress-bar-bg {
    background-color: #eee;
    height: 8px;
    border-radius: 4px;
    overflow: hidden;
}

.progress-bar-fill {
    background-color: var(--primary-color);
    height: 100%;
    width: 0%;
    transition: width 0.5s ease-in-out;
}

/* Typography */
h1 {
    font-size: 1.8rem;
    margin-bottom: 1.5rem;
    color: #2c3e50;
    text-align: center;
}

h2 {
    font-size: 1.4rem;
    margin-bottom: 1rem;
    color: #34495e;
}

p {
    margin-bottom: 1rem;
    color: #555;
}

/* Form Elements */
.options-group {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin: 2rem 0;
}

.option-label {
    display: flex;
    align-items: center;
    padding: 1rem;
    border: 2px solid #eee;
    border-radius: 8px;
    cursor: pointer;
    transition: all var(--transition-speed);
}

.option-label:hover {
    border-color: var(--primary-color);
    background-color: var(--secondary-color);
}

.option-label input[type="radio"] {
    margin-right: 1rem;
    accent-color: var(--primary-color);
    transform: scale(1.2);
}

/* Buttons */
.actions {
    display: flex;
    justify-content: space-between;
    margin-top: 2rem;
    gap: 1rem;
}

.btn {
    padding: 0.8rem 2rem;
    border: none;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color var(--transition-speed), transform 0.1s;
    text-decoration: none;
    display: inline-block;
}

.btn:active {
    transform: scale(0.98);
}

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

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

.btn-secondary {
    background-color: #e0e0e0;
    color: #555;
}

.btn-secondary:hover {
    background-color: #d0d0d0;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

/* Footer */
footer {
    background-color: #fff;
    padding: 2rem 0;
    border-top: 1px solid #eee;
    margin-top: auto;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    font-size: 0.9rem;
}

.footer-section h3 {
    margin-bottom: 1rem;
    color: #2c3e50;
    font-size: 1.1rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: #666;
    text-decoration: none;
    transition: color 0.2s;
}

.footer-section a:hover {
    color: var(--primary-color);
}

.copyright {
    text-align: center;
    margin-top: 2rem;
    padding-top: 1rem;
    border-top: 1px solid #eee;
    color: #888;
    font-size: 0.85rem;
}

/* Responsive */
@media (max-width: 600px) {
    .survey-card {
        padding: 1.5rem;
    }
    
    h1 {
        font-size: 1.5rem;
    }
    
    .actions {
        flex-direction: column-reverse;
    }
    
    .btn {
        width: 100%;
        text-align: center;
    }
}