/* 电路板 SVG 背景（无缝、低透明度） */
body {
    background: url("data:image/svg+xml,%3Csvg width='100' height='100' viewBox='0 0 100 100' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M0 0h100v100H0z' fill='%23000'/%3E%3Cg fill='none' stroke='%23004d4d' stroke-width='0.5' opacity='0.3'%3E%3Cpath d='M0 25h100M0 50h100M0 75h100M25 0v100M50 0v100M75 0v100'/%3E%3Ccircle cx='25' cy='25' r='2' fill='%2300ffff' opacity='0.2'/%3E%3Ccircle cx='75' cy='75' r='2' fill='%238a2be2' opacity='0.2'/%3E%3C/g%3E%3C/svg%3E"),
    #000;
    color: #fff;
    font-family: 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    overflow-x: hidden;
    line-height: 1.6;
    padding-top: 80px;
    min-height: 100vh;
}
.hero-image {
    background-image: url('../img/banner.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    min-height: 100vh;
}
.cyber-card {
    position: relative;
    border-radius: 16px !important;
    padding: 24px !important;
    background: rgba(0, 0, 0, 0.6) !important;
    backdrop-filter: blur(8px);
    box-shadow: inset 0 0 10px rgba(0, 255, 255, 0.3);
    border: 2px solid transparent !important;
    margin-bottom: 1.5rem;
    z-index: 2;
}
.cyber-card::before {
    content: '';
    position: absolute;
    top: -4px;
    left: -4px;
    right: -4px;
    bottom: -4px;
    border-radius: 20px;
    background: linear-gradient(90deg, #00ffff, #8a2be2);
    opacity: 0.7;
    z-index: -1;
    filter: blur(2px);
}
.main-title {
    font-size: 3rem;
    font-weight: bold;
    text-align: center;
    color: #fff;
    text-shadow: 0 0 10px #00ffff, 0 0 20px #8a2be2;
    margin-bottom: 10px;
    letter-spacing: 1px;
}
.subtitle {
    font-size: 1.3rem;
    color: #00ffff;
    text-align: center;
    margin-bottom: 10px;
    text-shadow: 0 0 8px #00ffff;
}
.tagline {
    font-size: 1.1rem;
    color: #00ffff;
    text-align: center;
    margin-bottom: 20px;
    text-shadow: 0 0 8px #00ffff;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}
.day-title {
    margin-bottom: 15px;
    text-align: center;
    font-size: 1.6rem;
    color: #ff00ff;
    text-shadow: 0 0 8px #ff00ff;
}
.feature-tags-container {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    margin-top: 12px;
}
.feature-tag {
    padding: 6px 12px;
    background: rgba(0, 0, 0, 0.1);
    border: 2px solid #00ffff;
    border-radius: 8px;
    color: white;
    font-size: 0.95rem;
    font-weight: bold;
    text-align: center;
    box-shadow: 0 0 8px rgba(0, 255, 255, 0.5), inset 0 0 4px rgba(0, 255, 255, 0.3);
    transition: all 0.25s ease;
    position: relative;
    overflow: hidden;
    white-space: nowrap;
}
.feature-tag::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, transparent, rgba(0, 255, 255, 0.25), transparent);
    z-index: -1;
    animation: glow 2s infinite alternate;
}
@keyframes glow {
    from {
        opacity: 0.4;
    }
    to {
        opacity: 0.8;
    }
}
.feature-tag:hover {
    transform: scale(1.03);
    box-shadow: 0 0 12px rgba(0, 255, 255, 0.7), inset 0 0 6px rgba(0, 255, 255, 0.4);
}
.description {
    color: #00ffff;
    line-height: 1.6;
    margin-top: 16px;
    font-size: 1rem;
    white-space: pre-line;
}
.connector {
    height: 2px;
    background: linear-gradient(to right, transparent, #00ffff, transparent);
    opacity: 0.8;
    position: relative;
    margin: 30px auto;
    width: 80%;
}
.connector::after {
    content: '';
    position: absolute;
    width: 20px;
    height: 20px;
    background: radial-gradient(circle, #00ffff, transparent);
    border-radius: 50%;
    top: -8px;
    left: 50%;
    transform: translateX(-50%);
    animation: pulse 2s infinite;
}
@keyframes pulse {
    0%,
    100% {
        transform: translateX(-50%) scale(1);
    }
    50% {
        transform: translateX(-50%) scale(1.2);
    }
}
.cta-section {
    text-align: center;
    padding: 25px;
    border-radius: 20px;
    border: 2px solid #00ffff;
    box-shadow: 0 0 20px rgba(0, 255, 255, 0.5), inset 0 0 10px rgba(0, 255, 255, 0.3);
    background: rgba(0, 0, 0, 0.6);
    position: relative;
    overflow: hidden;
}
.cta-bg{
    background: url('../img/bg.jpg');
    background-size: 100% 100%;
}
.cta-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, #00ffff, #8a2be2);
    opacity: 0.2;
    z-index: -1;
    border-radius: 20px;
}
.cta-text {
    margin-bottom: 0;
    font-size: 1.7rem;
    font-weight: bold;
    color: #fff;
    text-shadow: 0 0 10px #00ffff, 0 0 20px #8a2be2;
    line-height: 1.4;
}
@media (max-width: 992px) {
    .main-title {
        font-size: 2.2rem;
    }
    .icon-img {
        max-height: 160px;
        object-fit: contain;
    }
    .cyber-card {
        padding: 20px !important;
    }
    .description {
        font-size: 0.95rem;
    }
    .feature-tag {
        font-size: 0.9rem;
        padding: 5px 10px;
    }
    .cta-text {
        font-size: 1.3rem;
    }
}
.footer-link {
    color: #00ffff;
    transition: all 0.25s ease;
    border-radius: 6px;
    width: fit-content;
}
.footer-link:hover {
    color: #ff00ff;
    background: rgba(0, 255, 255, 0.15);
    text-shadow: 0 0 8px #00ffff;
    transform: translateX(4px);
}