html {
    scroll-behavior: smooth;
}

.navbar {
    transform: translateY(0) !important;
}

body {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    align-items: center;
    overflow-y: auto;
    scrollbar-width: none;
    -ms-overflow-style: none;
}

body::-webkit-scrollbar {
    display: none;
}

.page-content {
    width: 100%;
    padding-top: 8rem;
    padding-bottom: 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.about-logo {
    width: 280px;
    height: auto;
    opacity: 0.9;
    filter: drop-shadow(0 0 30px rgba(11, 79, 108, 0.15));
    transition: transform 0.3s ease;
    margin-bottom: 3rem;
}

.about-logo:hover {
    transform: scale(1.03);
}

.timeline-container {
    position: relative;
    width: 100%;
    max-width: 700px;
    display: flex;
    justify-content: center;
    flex: 1;
    overflow: visible;
}

.vertical-line {
    position: relative;
    width: 2px;
    background-color: #0b4f6c;
    opacity: 0.6;
    min-height: 1400px;
}

.vertical-line::before {
    content: '';
    position: absolute;
    top: -6px;
    left: 50%;
    transform: translateX(-50%);
    width: 10px;
    height: 10px;
    background-color: #0b4f6c;
    border-radius: 50%;
    opacity: 1;
}

.glass-card {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(10px);
    border-radius: 22px;
    box-shadow: 0 12px 24px rgba(11, 79, 108, 0.12),
                inset 0 1px 2px rgba(255, 255, 255, 0.6),
                inset 0 -2px 4px rgba(0, 0, 0, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.8);
    padding: 1.5rem;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.glass-card:hover {
    transform: scale(1.03);
    box-shadow: 0 16px 30px rgba(11, 79, 108, 0.25),
                inset 0 1px 3px rgba(255, 255, 255, 0.7),
                inset 0 -2px 6px rgba(0, 0, 0, 0.08);
}

.about-card {
    position: absolute;
    width: 300px;
    text-align: left;
    color: #1a3a4b;
    z-index: 2;
    overflow: visible;
    opacity: 0;                         /* 初始隐藏，由动画控制显示 */
}

.card-1 {
    right: calc(50% + 20px);
    top: 0;
}

.card-2 {
    left: calc(50% + 20px);
    top: 450px;
}

.card-3 {
    right: calc(50% + 20px);
    top: 900px;
    min-height: 240px;
}

.about-card h3 {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    font-size: 1.2rem;
    font-weight: 600;
    color: #0b4f6c;
    margin-bottom: 0.8rem;
}

.about-card p {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    font-size: 0.95rem;
    color: #2c4b5c;
    line-height: 1.6;
    margin: 0;
}

.big-number {
    position: absolute;
    bottom: -60px;
    left: 50%;
    transform: translateX(-50%);
    font-size: 16rem;
    font-weight: 700;
    color: #b3e5fc;
    z-index: -1;
    pointer-events: none;
    line-height: 1;
    opacity: 0.8;
    filter: blur(2px);
    -webkit-mask-image: linear-gradient(to bottom, black 40%, transparent 95%);
    mask-image: linear-gradient(to bottom, black 40%, transparent 95%);
}

.bottom-cta {
    width: 100%;
    height: 300px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    background: transparent;
    margin-top: -40px;
    position: relative;
    z-index: 1;
}

.bottom-cta-text {
    font-size: 3rem;
    font-weight: 700;
    color: #0b4f6c;
    text-align: center;
    padding: 0 2rem;
    line-height: 1.2;
    mask-image: linear-gradient(to bottom, black 30%, transparent 100%);
    -webkit-mask-image: linear-gradient(to bottom, black 30%, transparent 100%);
    transition: opacity 0.3s;
}

.bottom-cta:hover .bottom-cta-text {
    opacity: 0.8;
}

@media (max-width: 768px) {
    .page-content {
        padding-top: 5rem;
    }
    .about-logo {
        width: 200px;
    }
    .vertical-line {
        min-height: 800px;
    }
    .about-card {
        width: 240px;
        padding: 1.2rem;
    }
    .card-1 {
        right: calc(50% + 10px);
    }
    .card-2 {
        left: calc(50% + 10px);
        top: 400px;
    }
    .card-3 {
        right: calc(50% + 10px);
        top: 800px;
        min-height: 300px;
    }
    .big-number {
        font-size: 8rem;
        bottom: -30px;
    }
    .bottom-cta {
        height: 200px;
        margin-top: -30px;
    }
    .bottom-cta-text {
        font-size: 1.8rem;
    }
}

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

.card-1 {
    animation: fadeInUp 0.8s ease 0.2s forwards;
}

.card-2 {
    animation: fadeInUp 0.8s ease 0.5s forwards;
}

.card-3 {
    animation: fadeInUp 0.8s ease 0.8s forwards;
}