/* 欢迎界面容器 */
.welcome-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 2000;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
    opacity: 1;
    transition: opacity 1s ease-out;
    background: #fff5f5;
}

/* 欢迎内容容器 */
.welcome-content {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 30px;
    z-index: 1;
    pointer-events: none;
}

/* 流体背景 */
.fluid-background {
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: linear-gradient(
        115deg,
        rgba(227, 24, 55, 0.03) 0%,
        rgba(227, 24, 55, 0.1) 25%,
        rgba(227, 24, 55, 0.15) 50%,
        rgba(227, 24, 55, 0.1) 75%,
        rgba(227, 24, 55, 0.03) 100%
    );
    animation: gradientMove 8s ease-in-out infinite;
    filter: blur(30px);
    pointer-events: none;
}

.fluid-background::before,
.fluid-background::after {
    display: none;
}

/* 欢迎文本 */
.welcome-text {
    position: relative;
    font-size: 48px;
    color: #e31837;
    font-weight: 700;
    text-shadow: 2px 2px 4px rgba(227, 24, 55, 0.1);
    opacity: 0;
    transform: translateY(-20px);
    animation: welcomeTextAnim 1.5s ease-out forwards;
    mix-blend-mode: multiply;
}

/* 进入按钮 */
.enter-button {
    position: relative;
    border: none;
    background: none;
    cursor: pointer;
    opacity: 0;
    transform: translateY(20px);
    animation: enterButtonAnim 1.5s ease-out 0.5s forwards;
    pointer-events: auto;
}

.enter-button span {
    padding-bottom: 7px;
    letter-spacing: 4px;
    font-size: 14px;
    padding-right: 15px;
    text-transform: uppercase;
    font-weight: 500;
    color: #e31837;
}

.enter-button svg {
    transform: translateX(-8px);
    transition: all 0.3s ease;
    width: 20px;
    height: 20px;
    vertical-align: middle;
}

.enter-button:hover svg {
    transform: translateX(0);
}

.enter-button:active svg {
    transform: scale(0.9);
}

.hover-underline-animation {
    position: relative;
    padding-bottom: 20px;
}

.hover-underline-animation:after {
    content: "";
    position: absolute;
    width: 100%;
    transform: scaleX(0);
    height: 1.5px;
    bottom: 0;
    left: 0;
    background-color: #e31837;
    transform-origin: bottom right;
    transition: transform 0.25s ease-out;
}

.enter-button:hover .hover-underline-animation:after {
    transform: scaleX(1);
    transform-origin: bottom left;
}

/* 动画关键帧 */
@keyframes welcomeTextAnim {
    0% {
        opacity: 0;
        transform: translateY(-20px);
    }
    100% {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes enterButtonAnim {
    0% {
        opacity: 0;
        transform: translateY(20px);
    }
    100% {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes gradientMove {
    0% {
        transform: translate(0, 0) rotate(0deg);
    }
    50% {
        transform: translate(-5%, 5%) rotate(3deg);
    }
    100% {
        transform: translate(0, 0) rotate(0deg);
    }
}

/* 主内容区域过渡 */
body > *:not(.welcome-screen) {
    opacity: 0;
    transition: opacity 1s ease-in;
}