/* ===== CSS 变量（亮色主题） ===== */
:root {
    --bg: #f9fafc;
    --bg-card: #ffffff;
    --text: #1c1c24;
    --text-secondary: #5a5a6a;
    --text-muted: #6b6b7a;
    --text-tertiary: #8e8e9e;
    --border: rgba(0, 0, 0, 0.04);
    --border-medium: rgba(0, 0, 0, 0.08);
    --border-strong: #d0d0da;
    --gold: #c9a84c;
    --gold-dark: #b8922f;
    --gold-glow: rgba(201, 168, 76, 0.08);
    --gold-glow-strong: rgba(201, 168, 76, 0.15);
    --btn-primary-bg: #1c1c24;
    --btn-primary-bg-hover: #2f2f3a;
    --shadow-card: 0 2px 12px rgba(0,0,0,0.03), 0 1px 4px rgba(0,0,0,0.02);
    --shadow-card-hover: 0 12px 40px rgba(0,0,0,0.06);
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg: #121218;
        --bg-card: #1c1c24;
        --text: #f0f0f5;
        --text-secondary: #a0a0b0;
        --text-muted: #888898;
        --text-tertiary: #707080;
        --border: rgba(255, 255, 255, 0.06);
        --border-medium: rgba(255, 255, 255, 0.1);
        --border-strong: #3a3a48;
        --gold: #d4b45a;
        --gold-dark: #c9a84c;
        --gold-glow: rgba(201, 168, 76, 0.12);
        --gold-glow-strong: rgba(201, 168, 76, 0.2);
        --btn-primary-bg: #f0f0f5;
        --btn-primary-bg-hover: #ffffff;
        --shadow-card: 0 2px 12px rgba(0,0,0,0.2);
        --shadow-card-hover: 0 12px 40px rgba(0,0,0,0.35);
    }
}

/* ===== 重置 & 基础 ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    transition: background 0.3s ease, color 0.3s ease;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

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

/* ===== 导航 ===== */
.navbar {
    display: flex;
    align-items: center;
    padding: 1.2rem 0;
    border-bottom: 1px solid var(--border);
}
.back-link {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.95rem;
    transition: color 0.2s;
}
.back-link:hover { color: var(--gold); }

/* ===== 英雄区 ===== */
.hero {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: 4rem 0 3rem;
    position: relative;
    overflow: hidden;
}
.hero::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 500px;
    height: 350px;
    background: radial-gradient(ellipse at center, var(--gold-glow) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
    z-index: 0;
}
.hero > * { position: relative; z-index: 1; }

.hero .project-icon {
    font-size: 5rem;
    margin-bottom: 1rem;
    line-height: 1;
}
.hero h1 {
    font-size: clamp(2.2rem, 5vw, 3.2rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.1;
}
.hero .tagline {
    font-size: 1.3rem;
    color: var(--gold);
    font-weight: 500;
    margin-top: 0.3rem;
}
.hero .description {
    font-size: 1.15rem;
    color: var(--text-secondary);
    max-width: 520px;
    margin-top: 1.2rem;
    line-height: 1.7;
}

/* ===== 状态徽章 ===== */
.status-badge {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    padding: 0.25rem 1rem;
    border-radius: 20px;
    margin-top: 1.5rem;
    border: 1px solid var(--border-medium);
    color: var(--text-tertiary);
}
.status-badge.live {
    color: var(--gold);
    border-color: var(--gold);
    background: var(--gold-glow);
}

/* ===== 特性卡片 ===== */
.features {
    padding: 2rem 0 3rem;
    border-top: 1px solid var(--border);
}
.features h2 {
    font-size: 1.5rem;
    font-weight: 600;
    letter-spacing: -0.01em;
    text-align: center;
    margin-bottom: 0.3rem;
}
.features h2::after {
    content: '';
    display: block;
    width: 32px;
    height: 3px;
    background: var(--gold);
    margin: 0.5rem auto 0;
    border-radius: 2px;
}
.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}
.feature-item {
    background: var(--bg-card);
    border-radius: 12px;
    padding: 1.5rem;
    border: 1px solid var(--border);
    text-align: center;
}
.feature-item .feature-icon {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}
.feature-item h3 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 0.3rem;
}
.feature-item p {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ===== CTA ===== */
.cta {
    text-align: center;
    padding: 1rem 0 3rem;
}
.btn {
    display: inline-block;
    padding: 0.8rem 2.4rem;
    border-radius: 40px;
    font-weight: 600;
    font-size: 0.95rem;
    text-decoration: none;
    transition: all 0.25s ease;
    border: 1px solid transparent;
    cursor: pointer;
}
.btn-primary {
    background: var(--btn-primary-bg);
    color: var(--bg);
    box-shadow: 0 4px 14px rgba(0,0,0,0.06);
}
.btn-primary:hover {
    background: var(--btn-primary-bg-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0,0,0,0.08);
}
.btn-secondary {
    background: transparent;
    color: var(--text);
    border-color: var(--border-strong);
}
.btn-secondary:hover {
    border-color: var(--gold);
    color: var(--gold);
    background: var(--gold-glow);
}

/* ===== 页脚 ===== */
.footer {
    border-top: 1px solid var(--border);
    padding: 1.5rem 0;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.85rem;
}

/* ===== 响应式 ===== */
@media (max-width: 600px) {
    .container { padding: 0 1.2rem; }
    .hero { padding: 2.5rem 0 2rem; }
    .hero .project-icon { font-size: 3.5rem; }
    .hero h1 { font-size: 1.8rem; }
    .feature-grid { grid-template-columns: 1fr; gap: 1rem; }
}