:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --bg-color: #f1f5f9;
    --card-bg: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --success-color: #10b981;
    --error-color: #ef4444;
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --border-radius: 12px;
}

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

body {
    font-family: 'Inter', 'Noto Sans JP', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

header {
    text-align: center;
    margin-bottom: 2rem;
}

h1 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

header p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background-color: var(--border-color);
    border-radius: 4px;
    margin: 1.5rem 0 0.5rem;
    overflow: hidden;
}

.progress {
    height: 100%;
    background-color: var(--primary-color);
    width: 0%;
    transition: width 0.3s ease;
}

.progress-text {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.card {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 2rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow);
}

section h2 {
    font-size: 1.2rem;
    margin-bottom: 1.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--border-color);
}

section p {
    font-weight: 600;
    margin: 1.5rem 0 1rem;
    color: var(--text-primary);
}

.form-group {
    margin-bottom: 1.5rem;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

input[type="text"] {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.2s;
}

input[type="text"]:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

/* Question styling */
.question-item {
    margin-bottom: 1.5rem;
    padding: 1rem;
    background-color: #f8fafc;
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.question-text {
    font-weight: 500;
    margin-bottom: 1rem;
    display: flex;
    gap: 0.5rem;
}

.question-num {
    color: var(--primary-color);
    font-weight: 700;
    min-width: 28px;
}

.options-group {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 0.5rem;
}

.radio-option {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
}

.radio-option input[type="radio"] {
    position: absolute;
    opacity: 0;
}

.radio-label {
    display: block;
    width: 100%;
    text-align: center;
    padding: 0.75rem 0.5rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background-color: white;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.2s;
}

.radio-option input[type="radio"]:checked + .radio-label {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

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

.form-actions {
    margin-top: 2rem;
    text-align: center;
}

.btn {
    padding: 1rem 2rem;
    font-size: 1.1rem;
    font-weight: 600;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
    font-family: inherit;
}

.primary-btn {
    background-color: var(--primary-color);
    color: white;
    width: 100%;
    max-width: 300px;
}

.primary-btn:hover:not(:disabled) {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
}

.primary-btn:disabled {
    background-color: #94a3b8;
    cursor: not-allowed;
    opacity: 0.7;
}

.hidden {
    display: none !important;
}

.text-center {
    text-align: center;
}

.success-icon {
    font-size: 4rem;
    color: var(--success-color);
    margin: 1rem 0;
    animation: scaleIn 0.5s ease-out;
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.9);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 1rem;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

@keyframes scaleIn {
    0% { transform: scale(0); }
    100% { transform: scale(1); }
}

@media (max-width: 600px) {
    .options-group {
        grid-template-columns: 1fr;
    }
    
    .card {
        padding: 1.5rem 1rem;
    }
}