:root {
    --bg-color: #0d1117;
    --text-color: #c9d1d9;
    --primary-color: #F7931A; /* Bitcoin Orange */
    --green-color: #2da44e;
    --red-color: #cf222e;
    --card-bg-color: #161b22;
    --border-color: #30363d;
}

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

body {
    font-family: 'Noto Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    display: flex;
    flex-direction: column;
    align-items: center;
    min-height: 100vh;
    padding: 2rem 1rem;
    text-align: center;
}

main {
    width: 100%;
    max-width: 900px;
}

.top-bar {
    position: absolute;
    top: 1rem;
    right: 1.5rem;
    z-index: 10;
}

.language-switcher button {
    background: none;
    border: 1px solid var(--border-color);
    color: var(--text-color);
    font-size: 0.9rem;
    cursor: pointer;
    padding: 0.4rem 0.8rem;
    transition: background-color 0.2s, color 0.2s;
}
.language-switcher button:first-child { border-radius: 8px 0 0 8px; }
.language-switcher button:last-child { border-radius: 0 8px 8px 0; }
.language-switcher button + button { margin-left: -1px; }

.language-switcher button:hover {
    background-color: var(--card-bg-color);
}
.language-switcher button.active {
    background-color: var(--primary-color);
    color: #000;
    font-weight: bold;
    border-color: var(--primary-color);
}

.content-section {
    padding: 2rem 0;
    border-bottom: 1px solid var(--border-color);
}
#faq-section { border-bottom: none; }


/* Block 1: Price (强化巨幕效果) */
.section-subtitle {
    font-size: 1.2rem;
    font-weight: 400;
    color: #8b949e;
    margin-bottom: 0.5rem;
}
.price-giant-text {
    font-family: 'Roboto Mono', monospace;
    font-size: clamp(3.5rem, 15vw, 8rem); /* 增大字体尺寸 */
    font-weight: 700;
    color: var(--primary-color);
    line-height: 1.1;
    text-shadow: 0 0 15px rgba(247, 147, 26, 0.3); /* 增加辉光效果 */
    transition: color 0.5s ease;
}
.price-change-text {
    font-family: 'Roboto Mono', monospace;
    font-size: clamp(1.5rem, 5vw, 2.5rem);
    font-weight: 700;
    margin-top: 0.5rem;
    transition: color 0.5s ease;
}
.price-remark-text {
    font-size: 1.1rem;
    margin-top: 1.5rem;
    color: #8b949e;
    height: 1.5em; 
}
.positive { color: var(--green-color) !important; }
.negative { color: var(--red-color) !important; }


/* Block 2: Anchors */
.section-title {
    font-size: 1.5rem;
    margin-bottom: 2rem;
}
.anchor-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
}
.anchor-item {
    background-color: var(--card-bg-color);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
}
.anchor-item .icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}
.anchor-item p {
    font-size: 1.1rem;
}
.anchor-value {
    font-family: 'Roboto Mono', monospace;
    font-weight: 700;
    font-size: 1.75rem;
    color: var(--primary-color);
    display: block;
    margin-bottom: 0.5rem;
}


/* Block 4: FAQ */
#faq-section {
    max-width: 650px;
    margin-left: auto;
    margin-right: auto;
    text-align: left;
}
.faq-item {
    margin-bottom: 2.5rem;
}
.faq-item h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
    color: var(--primary-color);
}
.faq-item p {
    color: var(--text-color);
    line-height: 1.7;
}
.faq-link {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: bold;
}
.faq-link:hover { text-decoration: underline; }

.cta-button {
    display: inline-block;
    background-color: var(--primary-color);
    color: #000;
    padding: 0.8rem 1.5rem;
    border-radius: 8px;
    text-align: center;
    font-weight: bold;
    margin-top: 1rem;
    text-decoration: none;
    transition: transform 0.2s, background-color 0.2s;
}
.cta-button:hover {
    background-color: #ffaa3a;
    transform: translateY(-2px);
}

footer {
    padding: 2rem 0;
    color: #8b949e;
    font-size: 0.9rem;
}

@media (max-width: 768px) {
    body { padding: 1rem; }
    .top-bar { position: static; margin-bottom: 2rem; }
    .anchor-grid { grid-template-columns: 1fr 1fr; gap: 1rem; }
}

@media (max-width: 480px) {
    .anchor-grid { grid-template-columns: 1fr; }
}