/* Top Navigation Styles */
.top-navigation {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(27, 31, 35, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    z-index: 10000;
    padding: 1rem 0;
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.8rem;
    text-decoration: none;
}

.nav-logo img {
    width: 2.5rem;
    height: 2.5rem;
    object-fit: contain;
}

.logo-text {
    font-size: 1.2rem;
    font-weight: 700;
    color: #ffffff;
    letter-spacing: 0.05em;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 2.5rem;
    white-space: nowrap;
    overflow: hidden;
}

.nav-item {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    letter-spacing: 0.05em;
    transition: all 0.3s ease;
    position: relative;
    white-space: nowrap;
    flex-shrink: 0;
}

.nav-item:hover {
    color: #9f6cf7;
}

.nav-item.active {
    color: #9f6cf7;
}

.nav-item.active::after {
    content: '';
    position: absolute;
    bottom: -0.5rem;
    left: 0;
    width: 100%;
    height: 2px;
    background: #9f6cf7;
}

.nav-auth {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-right: 1rem; /* 确保右边有固定间距 */
    flex-wrap: nowrap; /* 防止按钮换行 */
    flex-shrink: 0; /* 防止按钮收缩 */
}

.payment-btn, .login-btn, .signup-btn {
    color: #ffffff;
    text-decoration: none;
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    padding: 0.6rem 1.2rem;
    border-radius: 6px;
    transition: all 0.3s ease;
    min-width: 80px;
    text-align: center;
    white-space: nowrap;
    flex-shrink: 0;
    box-shadow: 0 2px 10px rgba(159, 108, 247, 0.3);
    border: none;
    background: linear-gradient(45deg, #9f6cf7, #6f8bf7);
    cursor: pointer;
    display: inline-block;
}

.payment-btn:hover, .login-btn:hover, .signup-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 15px rgba(159, 108, 247, 0.4);
    background: linear-gradient(45deg, #b784ff, #84a0ff);
}

.lang-btn {
    color: #ffffff;
    text-decoration: none;
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.1rem;
    text-transform: uppercase;
    padding: 0.6rem 1.2rem;
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 6px;
    transition: all 0.3s ease;
    background: rgba(255, 255, 255, 0.05);
    min-width: 60px; /* 设置最小宽度确保一致性 */
    text-align: center;
    white-space: nowrap; /* 防止文字换行 */
    flex-shrink: 0; /* 防止按钮收缩 */
}

.lang-btn:hover {
    transform: translateY(-1px);
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.5);
}

/* Adjust body padding to account for fixed nav */
body {
    padding-top: 5rem;
}

/* Center the entire homepage animation */
#wrapper {
    min-height: calc(100vh - 5rem);
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Mobile adjustments */
@media screen and (max-width: 600px) {
    body {
        padding-top: 4rem;
    }

    #wrapper {
        min-height: calc(100vh - 4rem);
    }
}

/* Responsive breakpoints - gradually hide navigation items */
@media screen and (max-width: 1024px) {
    .nav-container {
        padding: 0 1.5rem;
    }

    .nav-menu {
        gap: 2rem;
    }

    .nav-auth {
        gap: 0.8rem;
    }

    .login-btn, .signup-btn, .payment-btn {
        font-size: 0.8rem;
        padding: 0.5rem 1rem;
        min-width: 70px;
    }

    .lang-btn {
        font-size: 0.8rem;
        padding: 0.5rem 1rem;
        min-width: 50px;
    }
}


@media screen and (max-width: 920px) {
    .nav-container {
        padding: 0 1rem;
    }

    .nav-menu {
        gap: 1.2rem;
    }

    .nav-item {
        font-size: 0.8rem;
    }

    .nav-auth {
        gap: 0.8rem;
    }

    .login-btn, .signup-btn {
        font-size: 0.8rem;
        padding: 0.5rem 1rem;
        min-width: 70px;
    }

    .lang-btn {
        font-size: 0.8rem;
        padding: 0.5rem 1rem;
        min-width: 50px;
    }
}

@media screen and (max-width: 850px) {
    /* Hide contact first */
    .nav-item[data-nav-id="contact"] {
        display: none;
    }
}

@media screen and (max-width: 650px) {
    /* Hide introduction next */
    .nav-item[data-nav-id="intro"] {
        display: none;
    }
}

@media screen and (max-width: 550px) {
    /* Keep event timing and energy curve visible until the end */
    .nav-item:not([data-nav-id="curve"]):not([data-nav-id="timing"]) {
        display: none;
    }
}

@media screen and (max-width: 500px) {
    /* Hide all navigation menu */
    .nav-menu {
        display: none;
    }

    .nav-container {
        justify-content: space-between;
    }

    .nav-auth {
        gap: 0.4rem;
    }

    .login-btn, .signup-btn, .payment-btn {
        font-size: 0.7rem;
        padding: 0.4rem 0.7rem;
        letter-spacing: 0.05rem;
        min-width: 60px;
    }

    .lang-btn {
        font-size: 0.7rem;
        padding: 0.4rem 0.7rem;
        letter-spacing: 0.05rem;
        min-width: 45px;
    }

    .nav-logo .logo-text {
        font-size: 0.9rem;
    }

    body {
        padding-top: 4rem;
    }

    #wrapper {
        min-height: calc(100vh - 4rem);
    }

    .top-navigation {
        padding: 0.8rem 0;
    }
}

@media screen and (max-width: 480px) {
    .nav-container {
        padding-right: 0;
    }

    .nav-auth {
        gap: 0.25rem;
        flex-wrap: nowrap;
        overflow: hidden;
    }

    .login-btn, .signup-btn, .payment-btn {
        font-size: 0.65rem;
        padding: 0.35rem 0.5rem;
        min-width: 50px;
        white-space: nowrap;
        flex-shrink: 0;
    }

    .lang-btn {
        font-size: 0.65rem;
        padding: 0.35rem 0.5rem;
        min-width: 40px;
        white-space: nowrap;
        flex-shrink: 0;
    }

    .nav-logo .logo-text {
        font-size: 0.8rem;
    }

    .nav-logo img {
        width: 30px;
        height: 30px;
    }
}

@media screen and (max-width: 400px) {
    .nav-container {
        padding: 0 0.5rem;
    }

    .nav-auth {
        gap: 0.2rem;
    }

    .login-btn, .signup-btn, .payment-btn {
        font-size: 0.6rem;
        padding: 0.3rem 0.4rem;
        min-width: 45px;
    }

    .lang-btn {
        font-size: 0.6rem;
        padding: 0.3rem 0.4rem;
        min-width: 35px;
    }

    .nav-logo .logo-text {
        font-size: 0.75rem;
    }

    .nav-logo img {
        width: 28px;
        height: 28px;
    }
}

@media screen and (max-width: 350px) {
    .nav-auth {
        gap: 0.15rem;
    }

    .login-btn, .signup-btn, .payment-btn {
        font-size: 0.55rem;
        padding: 0.25rem 0.35rem;
        min-width: 40px;
    }

    .lang-btn {
        font-size: 0.55rem;
        padding: 0.25rem 0.35rem;
        min-width: 30px;
    }

    .nav-logo .logo-text {
        font-size: 0.7rem;
    }

    .nav-logo img {
        width: 25px;
        height: 25px;
    }
}

/* Large screen optimizations (31+ inch displays) */
@media screen and (min-width: 1920px) {
    .nav-container {
        max-width: 1600px;
        padding: 0 3rem;
    }

    .nav-menu {
        gap: 3rem;
    }

    .nav-item {
        font-size: 0.85rem;
    }

    .nav-auth {
        gap: 1.2rem;
        flex-direction: row; /* 确保在大屏幕上水平排列 */
        flex-wrap: nowrap;
    }

    .login-btn, .signup-btn, .payment-btn {
        font-size: 0.8rem;
        padding: 0.55rem 1.1rem;
        min-width: 75px;
        white-space: nowrap;
    }

    .lang-btn {
        font-size: 0.75rem;
        padding: 0.55rem 1.1rem;
        min-width: 55px;
        white-space: nowrap;
    }
}

/* Extra large screens (32+ inch displays) */
@media screen and (min-width: 2560px) {
    .nav-container {
        max-width: 2000px;
        padding: 0 4rem;
    }

    .nav-menu {
        gap: 4rem;
    }

    .nav-item {
        font-size: 0.9rem;
    }

    .nav-auth {
        gap: 1.5rem;
    }

    .login-btn, .signup-btn, .payment-btn {
        font-size: 0.82rem;
        padding: 0.6rem 1.2rem;
        min-width: 80px;
    }

    .lang-btn {
        font-size: 0.78rem;
        padding: 0.6rem 1.2rem;
        min-width: 60px;
    }
}

/* English page specific margin adjustment */
.nav-auth.english-page {
    margin-right: 0.6rem;
}