body {
    font-family: "PingFang SC", "Microsoft YaHei", -apple-system, sans-serif;
    scroll-behavior: smooth;
}

.glass-nav {
    backdrop-filter: blur(12px);
    background: rgba(255, 255, 255, 0.7);
}

.dark .glass-nav {
    background: rgba(18, 18, 18, 0.7);
}

.hero-gradient {
    background: radial-gradient(circle at 70% 30%, rgba(0, 82, 217, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 10% 80%, rgba(0, 82, 217, 0.05) 0%, transparent 40%);
}

.reveal {
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.6s ease-out;
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}

.t-card {
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.t-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 10px 30px rgba(0, 82, 217, 0.1);
}

.social-icon-group {
    display: inline-flex;
    align-items: center;
}

.social-tooltip {
    display: none;
    position: absolute;
    background: #fff;
    border-radius: 8px;
    padding: 4px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    z-index: 50;
    white-space: nowrap;
    border: 1px solid rgba(0,0,0,0.06);
}

.tooltip-top {
    left: 50%;
    bottom: calc(100% + 8px);
    transform: translateX(-50%);
    animation: tooltipFadeIn 0.25s ease-out;
}

.tooltip-top-right {
    left: calc(100% + 8px);
    bottom: calc(100% + 8px);
    transform: none;
    animation: tooltipFadeInRight 0.25s ease-out;
}

.tooltip-top-left {
    right: calc(100% + 8px);
    left: auto;
    bottom: calc(100% + 8px);
    transform: none;
    animation: tooltipFadeInLeft 0.25s ease-out;
}

.social-icon-group:hover .social-tooltip {
    display: block;
}

.social-tooltip img {
    display: block;
    width: 112px;
    height: 112px;
    object-fit: cover;
    border-radius: 8px;
    background: #fff;
}

.social-tooltip span {
    display: block;
    font-size: 12px;
    white-space: nowrap;
}

@keyframes tooltipFadeIn {
    from { opacity: 0; transform: translateX(-50%) translateY(10px); }
    to { opacity: 1; transform: translateX(-50%) translateY(0); }
}

@keyframes tooltipFadeInRight {
    from { opacity: 0; transform: translateX(-10px); }
    to { opacity: 1; transform: translateX(0); }
}

@keyframes tooltipFadeInLeft {
    from { opacity: 0; transform: translateX(10px); }
    to { opacity: 1; transform: translateX(0); }
}