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

/* 卡片亮/暗变量 */
:root {
    --bg-start: #f8f9fa;
    --bg-end: #e9ecef;
    --card-bg: rgba(255, 255, 255, 1);
    --card-border: rgba(255, 255, 255, 0.9);
    --text-primary: #212529;
    --text-secondary: #6c757d;
    --accent: #495057;
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

body.dark {
    --bg-start: #121212;
    --bg-end: #000000;
    --card-bg: rgba(0, 0, 0);
    --card-border: rgba(255, 255, 255, 0.1);
    --text-primary: #e9ecef;
    --text-secondary: #adb5bd;
    --accent: #ced4da;
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

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

html, body {
    height: 100%;
    overflow: hidden;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: #000; /* 固定黑色 */
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.container {
    width: 100%;
    max-width: 420px;
    padding: 20px;
}

.pay-card {
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--card-border);
    border-radius: 24px;
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: var(--transition);
    animation: fadeIn 0.8s ease-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.card-header {
    padding: 32px 32px 24px;
    text-align: center;
    border-bottom: 1px solid var(--card-border);
}

.card-title {
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 8px;
    letter-spacing: -0.5px;
}

.card-subtitle {
    font-size: 14px;
    color: var(--text-secondary);
    font-weight: 400;
}

.qr-container {
    padding: 32px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 24px;
}

.qr-frame {
    position: relative;
    width: 400px;
    height: 400px;
    overflow: hidden;
    transition: var(--transition);
    cursor: pointer;
}

.qr-frame img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    display: block;
}

.scan-hint {
    font-size: 13px;
    color: var(--text-secondary);
    text-align: center;
    line-height: 1.6;
    max-width: 280px;
}

.card-footer {
    padding: 24px 32px 32px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-text {
    font-size: 12px;
    color: var(--text-secondary);
}

.theme-toggle {
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    border-radius: 8px;
    transition: var(--transition);
    color: var(--text-secondary);
}

.theme-toggle:hover {
    background: var(--card-border);
    color: var(--text-primary);
}

.theme-toggle svg {
    width: 18px;
    height: 18px;
    fill: currentColor;
}

@media (max-width: 480px) {
    .container {
        padding: 16px;
        padding-bottom: 100px;
    }

    .card-header {
        padding: 24px 24px 20px;
    }

    .qr-container {
        padding: 24px;
    }

    .card-footer {
        padding: 20px 24px 24px;
    }

    .qr-frame {
        width: 100%;
        max-width: 400px;
        height: auto;
        aspect-ratio: 1;
    }
}