/* 响应式适配：屏幕较窄时折叠导航 */
@media screen and (max-width: 900px) {
    .header-container {
        flex-direction: column;
        align-items: center;
        gap: 20px;
    }

    .logo-area {
        margin-right: 0;
    }

    .nav-links {
        flex-wrap: wrap;
        justify-content: center;
        gap: 20px 30px;
    }
}
/* 针对超小屏幕的响应式调整 */
@media (max-width: 700px) {
    .card-inner {
        padding: 20px 20px 30px 20px;
    }

    .stats-grid {
        grid-template-columns: 1fr 1fr;
        gap: 20px;
    }

    .stat-item:nth-child(1),
    .stat-item:nth-child(2),
    .stat-item:nth-child(3) {
        grid-column: auto;
    }

    .stat-item:nth-child(4) {
        grid-column: 1 / 2;
    }

    .stat-item:nth-child(5) {
        grid-column: 2 / 3;
    }

    .header-pill .en {
        font-size: 18px;
    }

    .header-pill .zh {
        font-size: 18px;
    }

    .stat-item .number {
        font-size: 32px;
    }
}

@media (max-width: 450px) {
    .stats-grid {
        grid-template-columns: 1fr;
        gap: 25px;
    }

    .stat-item:nth-child(1),
    .stat-item:nth-child(2),
    .stat-item:nth-child(3),
    .stat-item:nth-child(4),
    .stat-item:nth-child(5) {
        grid-column: 1 / 2;
    }
}

/* ———— 响应式 ———— */
@media (max-width: 640px) {
    .brand-story {
        padding: 32px 24px 36px;
        border-radius: 36px 36px 28px 28px;
    }

    .story-header .label-cn {
        font-size: 10px;
        letter-spacing: 3px;
        padding: 3px 14px;
    }

    .story-header .label-en {
        font-size: 10px;
        letter-spacing: 2px;
        padding: 2px 12px;
    }

    .title-block h1 {
        font-size: 38px;
        letter-spacing: 8px;
    }

    .title-block .sub-en {
        font-size: 11px;
        letter-spacing: 6px;
    }

    .story-body {
        font-size: 15px;
        line-height: 1.95;
    }

    .promise-block {
        padding: 14px 16px 12px 18px;
    }

    .promise-block p {
        font-size: 15px;
    }

    .upgrade-block .upgrade-title {
        font-size: 17px;
    }

    .upgrade-block .upgrade-sub {
        font-size: 14px;
    }

    .brand-story::before {
        left: 24px;
        right: 24px;
    }
}

@media (max-width: 420px) {
    .brand-story {
        padding: 24px 16px 28px;
        border-radius: 28px;
    }

    .title-block h1 {
        font-size: 30px;
        letter-spacing: 5px;
    }

    .title-block .sub-en {
        font-size: 10px;
        letter-spacing: 4px;
    }

    .story-body {
        font-size: 14px;
        line-height: 1.9;
    }

    .story-body p {
        text-indent: 1.8em;
    }

    .promise-block p {
        font-size: 14px;
    }

    .upgrade-block .upgrade-title {
        font-size: 15px;
    }

    .upgrade-block .upgrade-sub {
        font-size: 13px;
    }

    .divider-wave {
        width: 48px;
        margin: 12px auto 16px;
    }
}