:root {
    --bg-color: #f5f5f7;
    --text-main: #1d1d1f;
    --text-sub: #86868b;
    --hero-title-gradient: linear-gradient(180deg, #2a1a12 0%, #784E33 55%, rgba(29, 29, 31, 0.65) 100%);
    --glass-bg: linear-gradient(135deg, rgba(255, 255, 255, 0.6) 0%, rgba(255, 255, 255, 0.3) 100%);
    --glass-border: rgba(0, 0, 0, 0.05);
    --glass-highlight: rgba(255, 255, 255, 0.8);
    --glass-shadow: 0 10px 30px rgba(0, 0, 0, 0.04);
    --glass-hover-shadow: 0 16px 40px rgba(0, 0, 0, 0.10);
    --btn-bg: #1d1d1f;
    --btn-text: #ffffff;
    --nav-bg: rgba(255, 255, 255, 0.6);
    --blob-opacity: 0.25;
    --blob-brown-opacity: 1;
}

[data-theme="dark"] {
    --bg-color: #000000;
    --text-main: #ffffff;
    --text-sub: rgba(255, 255, 255, 0.6);
    --hero-title-gradient: linear-gradient(180deg, #ffffff 0%, rgba(255, 255, 255, 0.5) 100%);
    --glass-bg: linear-gradient(135deg, rgba(255, 255, 255, 0.1) 0%, rgba(255, 255, 255, 0.02) 100%);
    --glass-border: rgba(255, 255, 255, 0.12);
    --glass-highlight: rgba(255, 255, 255, 0.2);
    --glass-shadow: 0 10px 30px rgba(0, 0, 0, 0.4);
    --glass-hover-shadow: 0 16px 40px rgba(0, 0, 0, 0.7);
    --btn-bg: #ffffff;
    --btn-text: #000000;
    --nav-bg: rgba(30, 30, 30, 0.5);
    --blob-opacity: 0.4;
    --blob-brown-opacity: 1;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    overflow-x: hidden;
    line-height: 1.6;
    transition: background-color 0.5s ease, color 0.5s ease;
}

.ambient-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    filter: blur(80px);
    opacity: var(--blob-opacity);
    transition: opacity 0.5s ease;
}

.blob { position: absolute; border-radius: 50%; animation: float 25s infinite ease-in-out alternate; }
.blob-first { width: 50vw; height: 50vw; background: #E0A458; top: -10%; left: -5%; opacity: var(--blob-brown-opacity); }
.blob-purple { width: 60vw; height: 60vw; background: #4300e1; bottom: -15%; right: -5%; animation-delay: -7s; }
.blob-blue { width: 40vw; height: 40vw; background: #00d4ff; top: 30%; left: 35%; animation-delay: -12s; }

:root .blob-purple, :root .blob-blue { display: none; }
[data-theme="dark"] .blob-purple, [data-theme="dark"] .blob-blue { display: block; }

@keyframes float {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(15vw, -5vh) scale(1.1); }
}

.liquid-nav {
    position: fixed;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    width: 92%;
    max-width: 1100px;
    height: 54px;
    padding: 0 24px;
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    border-radius: 100px;
    z-index: 1000;
    background: var(--nav-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    box-shadow: var(--glass-shadow);
    transition: all 0.5s ease;
}

.nav-brand {
    display: flex;
    align-items: center;
    justify-self: flex-start;
    grid-column: 1; /* 强制锁定在第 1 列 */
}

/* 导航图标占位盒子：尺寸增大50% (原28px -> 42px) */
#nav-icon-box {
    width: 0;
    height: 42px;
    margin-right: 0;
    transition: width 0.5s cubic-bezier(0.32, 0.72, 0, 1), margin-right 0.5s cubic-bezier(0.32, 0.72, 0, 1);
}

#nav-icon-box.active {
    width: 42px;
    margin-right: 12px;
}

.nav-logo { font-size: 18px; font-weight: 600; }
.nav-links { 
    display: flex; 
    gap: 24px; 
    justify-self: center;
    grid-column: 2; /* 强制锁定在第 2 列 */
}
.nav-links a { font-size: 13px; color: var(--text-sub); text-decoration: none; transition: color 0.3s; }
.nav-links a:hover { color: var(--text-main); }

.nav-actions { 
    display: flex; 
    gap: 12px; 
    align-items: center; 
    justify-self: flex-end;
    grid-column: 3; /* 即使中间空了，也强制锁定在第 3 列 */
}

/* 导航按钮占位盒子 */
#nav-btn-box {
    width: 0;
    height: 32px;
    transition: width 0.5s cubic-bezier(0.32, 0.72, 0, 1), margin-left 0.5s cubic-bezier(0.32, 0.72, 0, 1);
}

#nav-btn-box.active {
    width: 78px;
    margin-left: 8px;
}

.theme-btn {
    background: none; border: none; color: var(--text-main); cursor: pointer;
    display: flex; align-items: center; justify-content: center; padding: 6px;
    border-radius: 50%; transition: background 0.3s;
}
.theme-btn:hover { background: rgba(128, 128, 128, 0.2); }

main { padding: 0 24px 60px; max-width: 1200px; margin: 0 auto; }

.hero {
    text-align: center; min-height: 100vh; display: flex; flex-direction: column;
    justify-content: center; align-items: center; padding: 120px 20px 20px; margin-bottom: 0;
}

.main-icon-placeholder {
    width: 100px;
    height: 100px;
    margin-bottom: 24px;
}

/* 统一控制所有全局漂浮元素的通用样式 */
#ghost-icon {
    position: fixed;
    top: 0;
    left: 0;
    width: 100px;
    height: 100px;
    transform-origin: top left;
    z-index: 1001;
    pointer-events: none;
    will-change: transform;
    object-fit: contain;
}

.hero h1 {
    font-size: clamp(40px, 8vw, 80px); font-weight: 800; letter-spacing: -2px; line-height: 1.1; margin-bottom: 20px;
    background: var(--hero-title-gradient); -webkit-background-clip: text; -webkit-text-fill-color: transparent; transition: background 0.5s ease;
}

.hero p {
    font-size: clamp(18px, 2vw, 22px); max-width: 750px; margin: 0 auto 40px; font-weight: 500;
    background: var(--hero-title-gradient); -webkit-background-clip: text; -webkit-text-fill-color: transparent; transition: background 0.5s ease;
}

[data-theme="dark"] .hero p { background: none; -webkit-text-fill-color: initial; color: var(--text-sub); }

.btn-primary {
    background: var(--btn-bg); color: var(--btn-text); border: none; padding: 18px 40px;
    border-radius: 40px; font-size: 18px; font-weight: 600; cursor: pointer;
    transition: transform 0.2s cubic-bezier(0.2, 0, 0, 1), box-shadow 0.2s ease;
}
.btn-primary:hover { transform: scale(1.03); box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15); }
.btn-primary.full-width { width: 100%; margin-top: 20px; }

.liquid-glass {
    background: var(--glass-bg); backdrop-filter: blur(24px) saturate(150%);
    -webkit-backdrop-filter: blur(24px) saturate(150%); border: 1px solid var(--glass-border);
    border-top: 1px solid var(--glass-highlight); border-left: 1px solid var(--glass-highlight);
    box-shadow: var(--glass-shadow); border-radius: 28px;
    transition: transform 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94), box-shadow 0.35s ease;
}
.liquid-glass:hover { transform: translateY(-6px); box-shadow: var(--glass-hover-shadow); }

.bento-grid { display: grid; grid-template-columns: repeat(12, 1fr); gap: 24px; margin-bottom: 40px; }
.pricing-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 24px; }
.reveal-card { opacity: 0; transform: translateY(30px); }
.reveal-card.revealed { animation: fadeUp 0.7s cubic-bezier(0.23, 1, 0.32, 1) forwards; }

@keyframes fadeUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

.span-8 { grid-column: span 8; }
.span-4 { grid-column: span 4; }
.card-content { padding: 40px; display: flex; flex-direction: column; justify-content: center; height: 100%; }
.card-content h3 { font-size: 28px; margin-bottom: 12px; font-weight: 700; line-height: 1.2; }
.card-content p { color: var(--text-sub); font-size: 16px; }
.glass-placeholder { margin-top: 30px; height: 160px; border-radius: 16px; background: var(--glass-bg); border: 1px solid var(--glass-border); }
.price-content { padding: 50px 40px; text-align: center; display: flex; flex-direction: column; justify-content: center; height: 100%; }
.price { font-size: 42px; font-weight: 800; margin: 20px 0; letter-spacing: -1px; }

@media (max-width: 850px) {
    .span-8, .span-4 { grid-column: span 12; }
    .nav-links { display: none; }
    .hero { padding: 100px 10px 20px; }
    .hero h1 { font-size: 48px; }
}

.site-footer { text-align: center; padding: 60px 0 30px; color: var(--text-sub); font-size: 14px; opacity: 0.8; }
.footer-divider { width: 100%; height: 1px; background: var(--text-sub); opacity: 0.2; border-radius: 1px; margin: 0 auto 18px; max-width: 1300px; }
.site-footer p { padding: 0 24px; margin: 0; }