.hero-section {
    position: relative;
    height: 618px;
    background: linear-gradient(135deg, #131F33 0%, #263D7D 50%, #131F33 100%);
    overflow: hidden;
}

/* Animated circles */
.circle {
    position: absolute;
    border-radius: 50%;
    opacity: 1;

}

.circle-red-large {
    width: 110px;
    height: 110px;
    background: #E3171A;
    top: clamp(120px, 22vh, 150px);
    /* giới hạn vị trí theo chiều cao */
    left: clamp(60px, 7vw, 110px);
}


.circle-red-small {
    width: 40px;
    height: 40px;
    background: #ff3b3b;
    top: 10%;
    right: 5%;
    animation: float 9s ease-in-out infinite 3s;
}

.circle-red-tiny {
    width: 30px;
    height: 30px;
    background: #ff3b3b;
    bottom: 30%;
    right: 8%;
    animation: float 6s ease-in-out infinite 2.5s;
}

/* Curved lines */
.curved-lines {
    position: absolute;
    /* bám theo viewport */
    bottom: 0;
    right: 0;
    width: auto;
    /* giữ nguyên kích thước SVG */
    height: auto;
    pointer-events: none;
}



.curved-line {
    position: absolute;
    border: 2px solid rgba(99, 152, 255, 0.3);
    border-radius: 50%;
}

/* Digital head image */
.digital-head {
    position: absolute;
    left: 172px;
    bottom: 0;
    height: 100%;
    /* hoặc height: 618px nếu cần cố định */
}

.digital-head img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center;
}

/* Content */
.hero-content {
    position: relative;
    z-index: 10;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    text-align: center;
    padding: 2rem;
    gap: 48px;
}

.hero-heading {
    gap: 24px;
}

.hero-heading h1 {
    max-width: 1048px;
    font-size: 56px;
    font-weight: 600;
    color: white;
    margin: 3.5rem 0 1.5rem;
}

.hero-heading span {
    font-weight: 600;
    font-size: 36px;
    line-height: 48px;
    letter-spacing: -0.02em;
    color: rgba(255, 255, 255, 0.7);
}

.learn-more-btn {
    display: inline-block;
    padding: 1rem 2rem;
    background: white;
    color: #1F314D;
    font-size: 16px;
    font-weight: 600;
    border-radius: 50px;
    text-decoration: none;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    transition: all 0.4s ease;
    animation: fadeInUp 1s ease-out 0.6s backwards;
}

.learn-more-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}

.radar-decoration {
    position: absolute;
    bottom: -125px;
    left: 205px;
    width: 235px;
    height: 235px;
    pointer-events: none;
    z-index: 5;
}

.radar-circle {
    position: absolute;
    border-radius: 50%;
    border: 1px solid rgba(99, 152, 255, 0.3);
}

.radar-circle-outer {
    width: 235px;
    height: 235px;
    bottom: 0;
    left: 0;
}

.radar-circle-inner {
    width: 135px;
    height: 135px;
    bottom: 57.5px;
    left: 49.5px;
}


.radar-dot {
    position: absolute;
    width: 50px;
    height: 50px;
    background: #0A9AD1;
    border-radius: 50%;
    bottom: 185px;
    left: 25px;
}

@media (max-width: 768px) {

    .hero-section {
        height: 660px;
        padding: 40px 20px;
        position: relative;
    }

    .hero-content {
        height: 100%;
        margin-top: 15px;
        padding: 1.5rem;
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        text-align: center;
        gap: 0px;
    }

    .hero-heading h1 {
        font-size: 26px;
        line-height: 1.4;
        margin: 0 auto 5rem;
        max-width: 90%;
        word-break: break-word;
        text-align: center;
    }

    .hero-heading span {
        font-size: 18px;
    }

    .learn-more-btn {
        font-size: 14px;
        padding: 0.75rem 1.5rem;
    }


    .circle-red-large {
        top: 110px;
        left: 45px;
        width: 60px;
        height: 60px;
    }

    .digital-head {
        left: 70px;
    }

    .digital-head svg {
        width: 145px;
        height: 145px;
    }

    .curved-lines {
        right: -35px;
    }

    .curved-lines svg {
        width: 399px;
        height: 372px;
    }

    .radar-decoration {
        display: none;
    }
}