@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

:root {
    --primary-color: #000000;
    --secondary-color: #333333;
    --accent-color: #007AFF;
    --background-color: #F5F5F7;
    --text-color: #1D1D1F;
    --gray-light: #86868B;
}

/* Base Styles */
body {
    font-family: 'Inter', sans-serif;
    color: var(--text-color);
    line-height: 1.5;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
}

/* Animations */
.transition-all {
    transition: all 0.3s ease;
}

/* Form Elements */
input[type="radio"] {
    width: 1.25rem;
    height: 1.25rem;
    border-radius: 50%;
    border: 2px solid var(--gray-light);
    transition: all 0.2s ease;
}

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

select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='currentColor'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.75rem center;
    background-size: 1.5rem;
    padding-right: 2.5rem;
}

/* Custom Classes */
.gradient-text {
    background: linear-gradient(90deg, var(--primary-color) 0%, var(--accent-color) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.quiz-section {
    transition: opacity 0.3s ease;
}

.quiz-section:not(:first-child) {
    display: none;
}

/* Responsive Design */
@media (max-width: 768px) {
    h1 {
        font-size: 2.5rem;
    }
    
    .container {
        padding-left: 1rem;
        padding-right: 1rem;
    }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* 添加图片容器样式 */
.image-container {
    background-color: var(--background-color);
}

.image-container .relative {
    position: relative;
    width: 100%;
}

.image-container img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover; /* 确保图片填充容器并保持比例 */
}

/* 可以添加图片加载时的过渡效果 */
.image-container img {
    transition: opacity 0.3s ease;
}

.image-container img.loading {
    opacity: 0;
}

.image-container img.loaded {
    opacity: 1;
}