@media screen and (max-width: 768px) {
    .nav-menu {
        padding: 4vw 0;
    }

    .nav-menu ul {
        flex-direction: column;
        display: none;
        background: linear-gradient(to right, #2c3e50, #3498db);
        width: 100vw;
    }

    .nav-menu.expanded ul {
        display: flex;
    }

    .nav-menu li {
        display: none;
        margin: 1vw 0;
    }

    .nav-menu.expanded li {
        display: block;
        width: 100vw;
    }

    .nav-menu a {
        padding: 2vw;
        font-size: 4vw;
    }

    .content-section {
        margin-top: 20vw;
        margin-bottom: 4vw;
        width: 100vw;
        padding: 2vw;
    }

    #home {
        padding: 12vw 0;
    }

    #home h2 {
        font-size: 6vw;
        padding: 0 2vw;
    }

    #home p {
        font-size: 3.5vw;
        padding: 0 2vw;
    }

    .small-title {
        display: block;
    }

    .hamburger {
        display: block;
        right: 3vw;
        top: 3.5vw;
    }

    .notice {
        font-size: 4vw;
        padding: 2vw;
        margin: 3vw 0;
        width: 100%;
        border-radius: 8px;
    }

    .notice-icon {
        width: 5vw;
        height: 5vw;
        margin-right: 1vw;
    }

    .hamburger div {
        width: 5vw;
        height: 0.6vw;
        margin: 1vw 0;
    }

    #rental {
        flex-direction: column;
        padding: 2vw;
        margin-top: 4px;
    }

    .rental-left,
    .rental-right {
        border-right: none;
        border-bottom: 0.4vw dashed #ccc;
        padding: 2vw;
        width: 100vw;
    }

    .rental-left {
        order: 2;
    }

    .rental-right {
        order: 1;
        padding: 0;
    }

    .telegram-container {
        margin: 4vw 0;
    }

    .telegram-icon {
        width: 20vw;
        height: 20vw;
        margin-bottom: 2vw;
    }

    .rental-right-top {
        flex-direction: column;
        padding: 0;
    }

    .rental-right-top-left,
    .rental-right-top-right {
        border-right: none;
        border-bottom: 0.4vw dashed #ccc;
        padding-right: 0;
        padding-left: 0;
    }

    .rental-left h3::before,
    .rental-right-top-left h3::before,
    .rental-right-top-right h3::before,
    .rental-right-bottom h3::before {
        width: 8vw;
        height: 8vw;
        margin-right: 2vw;
    }

    .energy-buttons {
        justify-content: center;
        padding: 0 1vw;
        gap: 3vw;
        margin-bottom: 2vw;
    }

    .energy-button {
        font-size: 4vw;
        padding: 2.2vw 3.25vw;
    }

    .energy-input,
    .pen-input {
        width: 100%;
        font-size: 4vw;
        padding: 3vw;
    }

    .price-display,
    .address-display,
    .address-display-2 {
        width: 100%;
        padding: 3vw;
        font-size: 3.6vw;
    }

    .address-display,
    .address-display-2 {
        text-align: left;
        margin-bottom: 3vw;
    }

    .price-display::after,
    .address-display::after,
    .address-display-2::after {
        width: 5vw;
        height: 5vw;
        right: 2vw;
    }

    .exchange-address-div {
        justify-content: start;
    }

    .rental-info {
        font-size: 4vw;
        padding: 0 2vw;
        margin: 3vw 0;
    }

    .rental-right-bottom {
        padding-left: 0;
        padding-right: 0;
    }

    .rental-left p,
    .rental-left span {
        font-size: 4.4vw;
    }

    .exchange-inputs {
        flex-direction: column;
        gap: 0;
    }

    .exchange-title img {
        width: 10vw;
        height: 10vw;
        margin-right: 2vw;
    }

    .input-label {
        font-size: 4vw;
        margin: 0;
    }

    .exchange-input {
        font-size: 4vw;
        padding: 3vw;
        width: 70%;
    }

    .convert-icon {
        width: 10vw;
        height: 10vw;
        margin: 0;
    }

    .agent-section {
        width: 100%;
    }

    .agent-title img {
        width: 12vw;
        height: 12vw;
    }

    .feature-item img {
        width: 4vw;
        height: 4vw;
    }

    .feature-item {
        font-size: 3.5vw;
    }

    .feature-item img {
        width: 5vw;
        height: 5vw;
    }

    .about-header,
    #about p,
    .features-container {
        width: 100%;
        padding: 0 15px;
    }

    .exchange-info {
        flex-direction: column;
    }

    .exchange-info span {
        margin-top: 0;
        margin-right: 0px;
        margin-bottom: 0px;
        font-size: 3.5vw;
    }

    #exchange {
        margin-top: 6vw;
    }

    .rental-right-top {
        border: none;
    }

    .exchange-title {
        margin-bottom: 0;
    }

    .exchange-rate {
        margin: 0;
        font-size: 4vw;
    }

    .input-group,
    .two-input-group {
        display: flex;
        flex-direction: row;
        align-items: center;
        justify-content: space-between;
        width: 100%;
    }

    .two-input-group {
        justify-content: center;
    }

    .last-input-group {
        margin: 3vw 0;
    }

    .last-input-group>div:first-child {
        margin: 0 0 3vw 0;
        padding: 1vw 0;
    }

    .show-qrcode-div img {
        width: 7vw;
        height: 7vw;
    }

    .show-qrcode-div span {
        font-size: 3.8vw;
    }

    .rental-price {
        font-size: 4vw;
    }

    .price-display {
        width: auto;
        font-size: 10vw;
        padding: 2vw;
    }

    .rental-info-div-h4 {
        font-size: 4vw;
    }

    .rental-right-top-right .expandable-title {
        position: relative;
        cursor: pointer;
        padding-right: 30px;
    }

    .rental-right-top-right .expandable-title::after {
        content: '';
        position: absolute;
        right: 10px;
        top: 50%;
        width: 12px;
        height: 12px;
        border-right: 3px solid #ff9800;
        border-bottom: 3px solid #ff9800;
        transform: translateY(-50%) rotate(45deg);
        transition: transform 0.3s ease;
        animation: glowArrow 1.5s ease-in-out infinite;
    }

    @keyframes glowArrow {
        0% {
            opacity: 0.4;
        }
        50% {
            opacity: 1;
        }
        100% {
            opacity: 0.4;
        }
    }

    .rental-right-top-right .expandable-title.expanded::after {
        transform: translateY(-50%) rotate(-135deg);
    }

    .rental-right-top-right .expandable-content {
        max-height: 0;
        overflow: hidden;
        opacity: 0;
        transition: max-height 0.5s ease-in-out, opacity 0.3s ease-in-out;
    }

    .rental-right-top-right .expandable-content.expanded {
        max-height: 1000px;
        opacity: 1;
    }

}