:root {
    /* 浅色模式 (默认) */
    --page-bg: #f5f5f7;
    --card-bg: #ffffff;
    --text-primary: #1d1d1f;
    --text-secondary: #515154;
    --text-strong: #1d1d1f;
    --img-placeholder: #e5e5ea;
    --card-shadow: 0 10px 40px rgba(0, 0, 0, 0.08);

    /* 按钮颜色 */
    --btn-primary-bg: #007aff;
    --btn-primary-text: #ffffff;
    --btn-primary-hover: #006ce6;

    --btn-secondary-bg: #f2f2f7;
    --btn-secondary-text: #007aff;
    --btn-secondary-hover: #e5e5ea;

    /* 强调色 */
    --color-red: #ff3b30;
}

@media (prefers-color-scheme: dark) {
    :root {
        /* 深色模式 */
        --page-bg: #000000;          /* 纯黑背景 */
        --card-bg: #1c1c1e;          /* 深灰悬浮卡片层 */
        --text-primary: #f5f5f7;
        --text-secondary: #98989d;   /* 更柔和的次级文字 */
        --text-strong: #ffffff;
        --img-placeholder: #2c2c2e;
        --card-shadow: 0 10px 40px rgba(0, 0, 0, 0.4); /* 深色模式下加深阴影 */

        /* 按钮颜色 (深色模式下稍微降低饱和度，更舒适) */
        --btn-primary-bg: #0a84ff;
        --btn-primary-hover: #0073e6;

        --btn-secondary-bg: #2c2c2e;
        --btn-secondary-text: #0a84ff;
        --btn-secondary-hover: #3a3a3c;

        /* 强调色 */
        --color-red: #ff453a;
    }
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--page-bg);
    color: var(--text-primary);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    padding: 20px;
    box-sizing: border-box;
    -webkit-font-smoothing: antialiased;
    transition: background-color 0.3s ease, color 0.3s ease; /* 切换主题时的呼吸感 */
}

.card-container {
    background: var(--card-bg);
    border-radius: 20px;
    box-shadow: var(--card-shadow);
    max-width: 600px;
    width: 100%;
    position: relative;
    overflow: hidden;
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.page {
    width: 100%;
    box-sizing: border-box;
    transition: transform 0.55s cubic-bezier(0.32, 0.72, 0, 1), opacity 0.55s ease;
    position: absolute;
    top: 0;
    left: 0;
    display: flex;
    flex-direction: column;
    text-align: center;
}

.page.active {
    position: relative;
    transform: translateX(0);
    opacity: 1;
    z-index: 2;
    pointer-events: auto;
}
.page.prev {
    transform: translateX(-30%);
    opacity: 0;
    z-index: 1;
    pointer-events: none;
}
.page.next {
    transform: translateX(100%);
    opacity: 1;
    z-index: 3;
    pointer-events: none;
}

.hero-image {
    width: 100%;
    height: auto;
    display: block;
    background-color: var(--img-placeholder);
    max-height: 225px;
    object-fit: contain;
    transition: background-color 0.3s ease;
}

.content {
    padding: 32px 28px 40px;
}

h1 {
    font-size: 24px;
    font-weight: 600;
    letter-spacing: -0.015em;
    margin: 0 0 8px 0;
}

p {
    font-size: 15px;
    line-height: 1.47059;
    font-weight: 400;
    letter-spacing: -0.022em;
    color: var(--text-secondary);
    margin: 0 0 8px 0;
    transition: color 0.3s ease;
}

strong {
    color: var(--text-strong);
    font-weight: 600;
    transition: color 0.3s ease;
}

.highlight-red {
    color: var(--color-red);
}

/* 按钮通用样式 */
.action-button {
    display: inline-block;
    background-color: var(--btn-primary-bg);
    color: var(--btn-primary-text);
    padding: 12px 24px;
    border-radius: 980px;
    font-size: 15px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s ease;
    border: none;
    cursor: pointer;
    width: 80%;
    margin-bottom: 12px;
    box-sizing: border-box;
    font-family: inherit;
}

.action-button:hover {
    background-color: var(--btn-primary-hover);
    transform: scale(0.98);
}

/* 次级按钮样式 */
.secondary-button {
    background-color: var(--btn-secondary-bg);
    color: var(--btn-secondary-text);
    margin-bottom: 0;
}

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