/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 25%, #f093fb 50%, #f5576c 75%, #4facfe 100%);
    background-size: 400% 400%;
    animation: gradientShift 15s ease infinite;
    color: #1a1a1a;
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

/* 移动端优化：禁用复杂的背景动画 */
@media (max-width: 768px) {
    body {
        background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
        background-size: 100% 100%;
        animation: none;
    }
}

@keyframes gradientShift {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部样式 */
.header {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    height: 90px !important;
}

/* 公告栏样式 */
.announcement-bar {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.15), rgba(255, 255, 255, 0.08));
    backdrop-filter: blur(15px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    position: relative;
    z-index: 99;
    animation: slideDown 0.5s ease-out;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
}

@keyframes slideDown {
    from {
        transform: translateY(-100%);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.announcement-content {
    display: flex;
    align-items: center;
    gap: 20px;
    padding: 16px 0;
    position: relative;
}

.announcement-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, #667eea, #764ba2);
    border-radius: 50%;
    color: white;
    font-size: 18px;
    flex-shrink: 0;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
        box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
    }
    50% {
        transform: scale(1.05);
        box-shadow: 0 6px 20px rgba(102, 126, 234, 0.6);
    }
}

.announcement-text {
    flex: 1;
    color: white !important;
    font-size: 15px;
    line-height: 1.5;
    font-weight: bold;
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
}

.announcement-text p {
    margin: 0;
    color: white !important;
    font-weight: bold !important;
}

.announcement-qr {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    flex-shrink: 0;
    position: relative;
}

.qr-code {
    width: 90px;
    height: 90px;
    border-radius: 8px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    background: white;
    padding: 4px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}



.announcement-bar.hidden {
    animation: slideUp 0.3s ease-out forwards;
}

@keyframes slideUp {
    from {
        transform: translateY(0);
        opacity: 1;
    }
    to {
        transform: translateY(-100%);
        opacity: 0;
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .announcement-content {
        flex-direction: column;
        gap: 15px;
        text-align: center;
        padding: 20px 0;
    }
    
    .announcement-text {
        font-size: 14px;
        order: 2;
    }
    
    .announcement-icon {
        order: 1;
    }
    
    .announcement-qr {
        order: 3;
    }
    

    
    .qr-code {
        width: 100px;
        height: 100px;
    }
}





.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 25px 0;
    height: 90px !important;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-icon {
    display: flex;
    align-items: center;
    gap: 5px;
    color: #ffffff;
    font-size: 28px;
    position: relative;
    filter: drop-shadow(0 2px 8px rgba(255, 255, 255, 0.3));
}

.logo-image {
    width: 150px !important;
    height: 150px !important;
    border-radius: 30px;
    object-fit: contain;
    filter: drop-shadow(0 2px 8px rgba(255, 255, 255, 0.3));
    opacity: 1 !important;
    visibility: visible !important;
}


.logo-text {
    font-size: 28px;
    font-weight: 700;
    color: #ffffff;
    text-shadow: 
        0 0 10px rgba(255, 255, 255, 0.8),
        0 0 20px rgba(255, 255, 255, 0.6),
        0 0 30px rgba(255, 255, 255, 0.4),
        0 0 40px rgba(147, 51, 234, 0.3),
        0 0 50px rgba(236, 72, 153, 0.2);
    position: relative;
    filter: drop-shadow(0 0 15px rgba(255, 255, 255, 0.5));
    animation: magicGlow 3s ease-in-out infinite alternate;
}

@keyframes magicGlow {
    0% {
        text-shadow: 
            0 0 10px rgba(255, 255, 255, 0.8),
            0 0 20px rgba(255, 255, 255, 0.6),
            0 0 30px rgba(255, 255, 255, 0.4),
            0 0 40px rgba(147, 51, 234, 0.3),
            0 0 50px rgba(236, 72, 153, 0.2);
        filter: drop-shadow(0 0 15px rgba(255, 255, 255, 0.5));
    }
    33% {
        text-shadow: 
            0 0 10px rgba(255, 255, 255, 0.8),
            0 0 20px rgba(255, 255, 255, 0.6),
            0 0 30px rgba(255, 255, 255, 0.4),
            0 0 40px rgba(236, 72, 153, 0.3),
            0 0 50px rgba(245, 158, 11, 0.2);
        filter: drop-shadow(0 0 15px rgba(236, 72, 153, 0.5));
    }
    66% {
        text-shadow: 
            0 0 10px rgba(255, 255, 255, 0.8),
            0 0 20px rgba(255, 255, 255, 0.6),
            0 0 30px rgba(255, 255, 255, 0.4),
            0 0 40px rgba(245, 158, 11, 0.3),
            0 0 50px rgba(16, 185, 129, 0.2);
        filter: drop-shadow(0 0 15px rgba(245, 158, 11, 0.5));
    }
    100% {
        text-shadow: 
            0 0 10px rgba(255, 255, 255, 0.8),
            0 0 20px rgba(255, 255, 255, 0.6),
            0 0 30px rgba(255, 255, 255, 0.4),
            0 0 40px rgba(16, 185, 129, 0.3),
            0 0 50px rgba(59, 130, 246, 0.2);
        filter: drop-shadow(0 0 15px rgba(16, 185, 129, 0.5));
    }
}

.nav {
    display: flex;
    gap: 30px;
}

.nav-link {
    text-decoration: none;
    color: #666;
    font-weight: 500;
    font-size: 16px;
    transition: color 0.3s ease;
}

.nav-link:hover {
    color: #165DFF;
}

/* 主内容区域 */
.main {
    padding: 80px 0;
    min-height: calc(100vh - 200px);
    position: relative;
}

.hero {
    text-align: center;
    margin-bottom: 80px;
}

.hero-title {
    font-size: clamp(32px, 5vw, 56px);
    font-weight: 800;
    color: #ffffff;
    margin-bottom: 24px;
    line-height: 1.2;
    text-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    letter-spacing: -0.02em;
}

.hero-subtitle {
    font-size: clamp(16px, 2vw, 20px);
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 60px;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
    font-weight: 400;
}

/* 全新处理功能区 */
.processing-hub {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 40px;
    align-items: center;
    max-width: 1000px;
    margin: 0 auto;
    padding: 60px;
    background: rgba(255, 255, 255, 0.12);
    backdrop-filter: blur(40px);
    border-radius: 32px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    position: relative;
    overflow: hidden;
    box-shadow: 
        0 25px 80px rgba(0, 0, 0, 0.4),
        inset 0 1px 0 rgba(255, 255, 255, 0.3),
        inset 0 -1px 0 rgba(255, 255, 255, 0.1);
}

.processing-hub::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 6px;
    background: linear-gradient(90deg, #667eea, #764ba2, #f093fb, #f5576c, #4facfe);
    background-size: 300% 100%;
    animation: shimmer 4s ease-in-out infinite;
}

.processing-hub::after {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 30% 20%, rgba(102, 126, 234, 0.1) 0%, transparent 50%),
                radial-gradient(circle at 70% 80%, rgba(240, 147, 251, 0.1) 0%, transparent 50%);
    animation: backgroundFloat 20s ease-in-out infinite;
}

@keyframes backgroundFloat {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    33% { transform: translate(-20px, -20px) rotate(120deg); }
    66% { transform: translate(20px, -10px) rotate(240deg); }
}

/* 上传区域 */
.upload-zone {
    text-align: center;
    position: relative;
    z-index: 2;
}

.upload-area {
    border: 3px dashed rgba(255, 255, 255, 0.3);
    border-radius: 24px;
    padding: 50px 30px;
    background: rgba(255, 255, 255, 0.08);
    backdrop-filter: blur(20px);
    cursor: pointer;
    transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
}

.upload-pulse {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 100px;
    height: 100px;
    background: radial-gradient(circle, rgba(102, 126, 234, 0.3) 0%, transparent 70%);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    animation: uploadPulse 3s ease-in-out infinite;
}

@keyframes uploadPulse {
    0%, 100% {
        transform: translate(-50%, -50%) scale(1);
        opacity: 0.5;
    }
    50% {
        transform: translate(-50%, -50%) scale(1.5);
        opacity: 0;
    }
}

.upload-area:hover {
    border-color: rgba(255, 255, 255, 0.6);
    background: rgba(255, 255, 255, 0.15);
    transform: scale(1.02);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.upload-area.dragover {
    border-color: #667eea;
    background: rgba(102, 126, 234, 0.2);
    transform: scale(1.05);
    animation: dragoverShock 0.6s ease;
}

@keyframes dragoverShock {
    0% { transform: scale(1); }
    50% { transform: scale(1.08); }
    100% { transform: scale(1.05); }
}

.upload-area.disabled {
    opacity: 0.5;
    pointer-events: none;
    cursor: not-allowed;
    border-color: rgba(255, 255, 255, 0.1);
    background: rgba(255, 255, 255, 0.05);
    transform: none;
    box-shadow: none;
}

.upload-area.disabled::before {
    display: none;
}

.upload-area.disabled .upload-icon {
    animation: none;
    opacity: 0.3;
}

.upload-icon {
    font-size: 48px;
    color: #ffffff;
    margin-bottom: 20px;
    filter: drop-shadow(0 4px 15px rgba(255, 255, 255, 0.4));
    animation: iconFloat 4s ease-in-out infinite;
}

@keyframes iconFloat {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-5px); }
}

.upload-title {
    font-size: 24px;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 12px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

.upload-text {
    font-size: 16px;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 20px;
}

.format-chips {
    display: flex;
    gap: 10px;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 20px;
}

.chip {
    background: rgba(255, 255, 255, 0.15);
    color: #ffffff;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 600;
    border: 1px solid rgba(255, 255, 255, 0.3);
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

.chip:hover {
    background: rgba(255, 255, 255, 0.25);
    transform: scale(1.1);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

/* 转换箭头 */
.conversion-arrow {
    position: relative;
    z-index: 2;
    display: flex;
    align-items: center;
    justify-content: center;
}

.conversion-arrow i {
    font-size: 36px;
    color: #ffffff;
    filter: drop-shadow(0 4px 15px rgba(255, 255, 255, 0.4));
    animation: arrowMove 2s ease-in-out infinite;
}

@keyframes arrowMove {
    0%, 100% { transform: translateX(0); }
    50% { transform: translateX(10px); }
}

.arrow-pulse {
    position: absolute;
    width: 60px;
    height: 60px;
    background: radial-gradient(circle, rgba(240, 147, 251, 0.4) 0%, transparent 70%);
    border-radius: 50%;
    animation: arrowPulse 2s ease-in-out infinite;
}

@keyframes arrowPulse {
    0%, 100% {
        transform: scale(1);
        opacity: 0.6;
    }
    50% {
        transform: scale(1.3);
        opacity: 0;
    }
}

/* 输出区域 */
.output-zone {
    text-align: center;
    position: relative;
    z-index: 2;
}

.output-header {
    margin-bottom: 30px;
}

.output-title {
    font-size: 24px;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 20px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

/* 移动端优化：禁用箭头动画 */
@media (max-width: 768px) {
    .arrow-pulse {
        animation: none;
    }
}

.format-selector {
    display: flex;
    gap: 8px;
    justify-content: center;
    flex-wrap: wrap;
    max-width: 500px;
    margin: 0 auto;
}

.format-selector .format-btn {
    background: rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.8);
    border: 2px solid rgba(255, 255, 255, 0.2);
    padding: 10px 18px;
    border-radius: 16px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    backdrop-filter: blur(10px);
    position: relative;
    overflow: hidden;
    min-width: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    display: flex;
    align-items: center;
    gap: 8px;
    min-width: 120px;
    justify-content: center;
}

.format-btn i {
    font-size: 18px;
    transition: all 0.3s ease;
}

.format-btn:hover i {
    transform: scale(1.1);
}

.format-btn.active i {
    transform: scale(1.15);
    filter: drop-shadow(0 2px 5px rgba(255, 255, 255, 0.3));
}

.format-btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.3) 0%, transparent 70%);
    transition: all 0.6s ease;
    transform: translate(-50%, -50%);
}

.format-btn:hover::before {
    width: 100px;
    height: 100px;
}

.format-selector .format-btn:hover {
    background: linear-gradient(135deg, rgba(43, 87, 154, 0.3), rgba(30, 58, 138, 0.3));
    border-color: rgba(255, 255, 255, 0.4);
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

.format-selector .format-btn.active {
    background: linear-gradient(135deg, #2B579A, #1E3A8A) !important;
    color: #ffffff !important;
    border-color: transparent !important;
    transform: scale(1.05) !important;
    box-shadow: 0 10px 30px rgba(43, 87, 154, 0.4) !important;
}

.format-selector .format-btn.active:hover {
    transform: scale(1.08) translateY(-2px) !important;
}

/* 操作按钮区域 */
.action-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    margin-top: 30px;
    flex-wrap: wrap;
}

.action-hint {
    text-align: center;
    color: #666;
    font-size: 14px;
    margin-top: 15px;
}

/* 下载区域 */
.download-area {
    margin-top: 30px;
}

.convert-btn {
    background: linear-gradient(135deg, #667eea, #764ba2, #f093fb);
    background-size: 300% 300%;
    animation: convertGradient 4s ease infinite;
    color: #ffffff;
    border: none;
    border-radius: 20px;
    padding: 20px 40px;
    font-size: 18px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    display: inline-flex;
    align-items: center;
    gap: 12px;
    position: relative;
    overflow: hidden;
    box-shadow: 0 15px 40px rgba(102, 126, 234, 0.4);
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
    min-width: 180px;
    justify-content: center;
}

.download-btn {
    background: linear-gradient(135deg, #f093fb, #f5576c, #667eea);
    background-size: 300% 300%;
    animation: downloadGradient 4s ease infinite;
    color: #ffffff;
    border: none;
    border-radius: 20px;
    padding: 20px 40px;
    font-size: 18px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    display: inline-flex;
    align-items: center;
    gap: 12px;
    position: relative;
    overflow: hidden;
    box-shadow: 0 15px 40px rgba(240, 147, 251, 0.4);
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
    min-width: 180px;
    justify-content: center;
}

@keyframes convertGradient {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

@keyframes downloadGradient {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

.btn-shockwave {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.3) 0%, transparent 70%);
    border-radius: 20px;
    transform: translate(-50%, -50%) scale(0);
    animation: shockwave 3s ease-in-out infinite;
}

@keyframes shockwave {
    0%, 100% {
        transform: translate(-50%, -50%) scale(0);
        opacity: 0;
    }
    50% {
        transform: translate(-50%, -50%) scale(2);
        opacity: 0.6;
    }
}

@keyframes formatShockwave {
    0% {
        transform: translate(-50%, -50%) scale(0);
        opacity: 0.8;
    }
    100% {
        transform: translate(-50%, -50%) scale(3);
        opacity: 0;
    }
}

.download-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
    transition: left 0.8s ease;
}

.download-btn:hover:not(:disabled)::before {
    left: 100%;
}

.convert-btn:hover:not(:disabled) {
    transform: translateY(-3px) scale(1.05);
    box-shadow: 0 15px 40px rgba(102, 126, 234, 0.5);
    animation: convertGradient 2s ease infinite;
}

.download-btn:hover:not(:disabled) {
    transform: translateY(-3px) scale(1.05);
    box-shadow: 0 15px 40px rgba(240, 147, 251, 0.5);
    animation: downloadGradient 2s ease infinite;
}

.convert-btn:active:not(:disabled) {
    transform: translateY(-1px) scale(1.02);
}

.download-btn:active:not(:disabled) {
    transform: translateY(-1px) scale(1.02);
}

.convert-btn:disabled {
    background: rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.4);
    cursor: not-allowed;
    box-shadow: none;
    transform: none;
}

.download-btn:disabled {
    background: rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.4);
    cursor: not-allowed;
    box-shadow: none;
    transform: none;
}

.download-btn:disabled .btn-shockwave {
    animation: none;
}

.download-hint {
    margin-top: 15px;
    font-size: 14px;
    color: rgba(255, 255, 255, 0.6);
    font-style: italic;
}

/* 上传区域 */
.upload-section {
    margin-bottom: 40px;
}

.upload-area {
    border: 2px dashed rgba(255, 255, 255, 0.3);
    border-radius: 20px;
    padding: 50px 30px;
    text-align: center;
    cursor: pointer;
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(15px);
    position: relative;
    overflow: hidden;
}

.upload-area::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.2) 0%, transparent 70%);
    transition: all 0.8s ease;
    transform: translate(-50%, -50%);
}

.upload-area:hover::before {
    width: 400px;
    height: 400px;
}

.upload-area:hover {
    border-color: rgba(255, 255, 255, 0.6);
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-3px);
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.2);
}

.upload-area.dragover {
    border-color: rgba(255, 255, 255, 0.8);
    background: rgba(255, 255, 255, 0.25);
    transform: scale(1.03);
}

.upload-icon {
    font-size: 56px;
    color: #ffffff;
    margin-bottom: 20px;
    filter: drop-shadow(0 2px 10px rgba(255, 255, 255, 0.3));
}

.upload-text {
    font-size: 18px;
    color: #ffffff;
    margin-bottom: 12px;
    font-weight: 500;
}

.supported-formats {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.7);
    text-align: center;
    margin-top: 16px;
}

/* 分割线 */
.divider {
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    margin: 35px 0;
}

/* 格式选择 */
.format-section {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 35px;
}

.format-label {
    font-size: 16px;
    font-weight: 600;
    color: #ffffff;
    text-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
}

.select-wrapper {
    position: relative;
    min-width: 180px;
}

.format-select {
    width: 100%;
    padding: 12px 40px 12px 16px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(10px);
    font-size: 16px;
    color: #ffffff;
    cursor: pointer;
    appearance: none;
    transition: all 0.3s ease;
}

.format-select:hover {
    border-color: rgba(255, 255, 255, 0.5);
    background: rgba(255, 255, 255, 0.2);
}

.format-select:focus {
    outline: none;
    border-color: rgba(255, 255, 255, 0.7);
    background: rgba(255, 255, 255, 0.25);
    box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.1);
}

.format-select option {
    background: #333;
    color: #ffffff;
}

.select-wrapper::after {
    content: '\f078';
    font-family: 'Font Awesome 6 Free';
    font-weight: 900;
    position: absolute;
    right: 16px;
    top: 50%;
    transform: translateY(-50%);
    color: rgba(255, 255, 255, 0.7);
    pointer-events: none;
}

/* 下载区域 */
.download-section {
    text-align: center;
}

.download-btn {
    background: linear-gradient(135deg, #667eea, #764ba2, #f093fb);
    background-size: 200% 200%;
    animation: buttonGradient 3s ease infinite;
    color: #ffffff;
    border: none;
    border-radius: 16px;
    padding: 18px 48px;
    font-size: 18px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    display: inline-flex;
    align-items: center;
    gap: 12px;
    min-width: 200px;
    justify-content: center;
    position: relative;
    overflow: hidden;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
}

@keyframes buttonGradient {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}



.convert-btn:active:not(:disabled) {
    transform: translateY(-1px) scale(1.02);
}

.download-btn:active:not(:disabled) {
    transform: translateY(-1px) scale(1.02);
}

.download-btn:disabled {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.2), rgba(255, 255, 255, 0.1));
    color: rgba(255, 255, 255, 0.5);
    cursor: not-allowed;
    box-shadow: none;
    transform: none;
}

.convert-btn.success {
    animation: bounce 0.6s ease, glow 1s ease;
}

.download-btn.success {
    animation: bounce 0.6s ease, glow 1s ease;
}

/* 底部样式 */
.footer {
    background: rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(20px);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding: 40px 0;
    margin-top: 80px;
}

.footer-content {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 30px;
    font-size: 15px;
    color: rgba(255, 255, 255, 0.7);
    font-weight: 400;
    flex-wrap: wrap;
}

.beian-info {
    display: flex;
    align-items: center;
    gap: 8px;
}

.beian-link {
    display: inline-flex;
    align-items: center;
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: all 0.3s ease;
    font-weight: 500;
    font-size: 14px;
    padding: 4px 12px;
    border-radius: 20px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.beian-link:hover {
    color: #ffffff;
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.2);
    text-shadow: 0 2px 5px rgba(255, 255, 255, 0.3);
    transform: translateY(-1px);
}

.privacy-link {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: all 0.3s ease;
    font-weight: 500;
}

.privacy-link:hover {
    color: #ffffff;
    text-shadow: 0 2px 5px rgba(255, 255, 255, 0.3);
}

/* 提示气泡 */
.toast {
    position: fixed;
    top: 30px;
    left: 50%;
    transform: translateX(-50%) translateY(-100px);
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(20px);
    color: #FFFFFF;
    padding: 16px 32px;
    border-radius: 12px;
    font-size: 15px;
    font-weight: 600;
    z-index: 1000;
    opacity: 0;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    pointer-events: none;
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.toast.show {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
}

.toast.success {
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.9), rgba(5, 150, 105, 0.9));
    border-color: rgba(16, 185, 129, 0.3);
}

.toast.error {
    background: linear-gradient(135deg, rgba(239, 68, 68, 0.9), rgba(220, 38, 38, 0.9));
    border-color: rgba(239, 68, 68, 0.3);
}

.toast.warning {
    background: linear-gradient(135deg, rgba(245, 158, 11, 0.9), rgba(217, 119, 6, 0.9));
    border-color: rgba(245, 158, 11, 0.3);
}

/* 动画效果 */
@keyframes bounce {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-4px);
    }
}

@keyframes twinkle {
    0%, 100% {
        opacity: 1;
        transform: scale(1);
    }
    50% {
        opacity: 0.5;
        transform: scale(0.8);
    }
}

@keyframes shimmer {
    0% {
        transform: translateX(-100%);
    }
    100% {
        transform: translateX(200%);
    }
}

@keyframes glow {
    0%, 100% {
        box-shadow: 0 12px 30px rgba(139, 92, 246, 0.4);
    }
    50% {
        box-shadow: 0 12px 40px rgba(139, 92, 246, 0.6);
    }
}

/* 功能介绍卡片 */
.features-intro {
    margin: 80px 0;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 40px;
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
}

.intro-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(20px);
    border-radius: 24px;
    padding: 40px 30px;
    text-align: center;
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    position: relative;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.intro-card::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
    transition: all 0.8s ease;
    opacity: 0;
}

.intro-card:hover::before {
    opacity: 1;
}

.intro-card:hover {
    transform: translateY(-12px) scale(1.02);
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.3);
    border-color: rgba(255, 255, 255, 0.4);
}

.intro-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 25px;
    background: linear-gradient(135deg, #667eea, #764ba2, #f093fb);
    background-size: 200% 200%;
    animation: iconGradient 4s ease infinite;
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 32px;
    color: white;
    transition: all 0.5s ease;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.3);
}

@keyframes iconGradient {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

.intro-card:hover .intro-icon {
    transform: scale(1.15) rotate(8deg);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.4);
}

.intro-title {
    font-size: 22px;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 16px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

.intro-description {
    font-size: 16px;
    color: rgba(255, 255, 255, 0.8);
    line-height: 1.7;
    margin-bottom: 20px;
}

.intro-formats {
    margin-top: 20px;
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    justify-content: center;
}

.format-badge {
    background: rgba(255, 255, 255, 0.2);
    color: #ffffff;
    padding: 4px 10px;
    border-radius: 25px;
    font-size: 11px;
    font-weight: 600;
    border: 1px solid rgba(255, 255, 255, 0.3);
    transition: all 0.4s ease;
    backdrop-filter: blur(10px);
}

.format-badge:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: scale(1.08);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

/* 移动端性能优化 - 激进版本 */
@media (max-width: 768px) {
    /* 禁用所有复杂动画效果 */
    .logo-text {
        animation: none !important;
    }
    
    .upload-pulse {
        animation: none !important;
    }
    
    .btn-shockwave {
        animation: none !important;
    }
    
    .intro-card::before {
        display: none;
    }
    
    .intro-icon {
        animation: none !important;
    }
    
    .format-btn::before {
        display: none;
    }
    
    .convert-btn, .download-btn {
        animation: none !important;
    }
    
    /* 核心功能区激进优化 - 解决黑色过渡问题 */
    .processing-hub {
        backdrop-filter: none !important;
        background: rgba(255, 255, 255, 0.15) !important;
        box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2) !important;
        transition: none !important;
    }
    
    .processing-hub::before {
        display: none !important;
    }
    
    .processing-hub::after {
        display: none !important;
    }
    
    .upload-area {
        backdrop-filter: none !important;
        background: rgba(255, 255, 255, 0.1) !important;
        transition: none !important;
    }
    
    .upload-area:hover {
        transform: none !important;
        box-shadow: none !important;
        background: rgba(255, 255, 255, 0.12) !important;
    }
    
    .format-btn {
        backdrop-filter: none !important;
        transition: all 0.2s ease !important;
    }
    
    .format-btn:hover {
        transform: none !important;
        box-shadow: none !important;
    }
    
    /* 禁用滚动动画以提升性能 */
    .fade-in:not(.visible),
    .slide-up:not(.visible) {
        opacity: 1 !important;
        transform: none !important;
        transition: none !important;
        animation: none !important;
    }
    
    .fade-in.visible,
    .slide-up.visible {
        opacity: 1 !important;
        transform: none !important;
        visibility: visible !important;
    }
    
    /* 强制核心功能区立即显示 */
    .processing-hub {
        opacity: 1 !important;
        visibility: visible !important;
        display: grid !important;
        transform: none !important;
    }
    
    .upload-zone,
    .output-zone,
    .conversion-arrow {
        opacity: 1 !important;
        visibility: visible !important;
    }
    
    .announcement-icon {
        animation: none !important;
    }
    
    .intro-card:hover {
        transform: none !important;
        box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15) !important;
    }
    
    .chip:hover {
        transform: none !important;
    }
    
    /* 优化背景性能 */
    body {
        background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
        background-attachment: fixed;
    }
    
    /* 简化按钮效果 */
    .convert-btn:hover:not(:disabled),
    .download-btn:hover:not(:disabled) {
        transform: none !important;
        animation: none !important;
    }
    
    /* 移除所有will-change以减少GPU负担 */
    * {
        will-change: auto !important;
    }
    
    /* 禁用复杂的阴影和光晕 */
    .upload-icon {
        filter: none !important;
        animation: none !important;
    }
    
    /* 强制GPU加速关键元素 */
    .processing-hub,
    .upload-area,
    .format-btn {
        transform: translateZ(0);
        backface-visibility: hidden;
        perspective: 1000px;
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 0 16px;
    }
    
    .header-content {
        padding: 16px 0;
    }
    
    .logo-text {
        font-size: 20px;
    }
    
    .nav {
        gap: 20px;
    }
    
    .nav-link {
        font-size: 14px;
    }
    
    .main {
        padding: 40px 0;
    }
    
    .hero-title {
        font-size: 24px;
    }
    
    .hero-subtitle {
        font-size: 14px;
    }
    
    .feature-card {
        padding: 35px 20px;
    }
    
    .features-intro {
        grid-template-columns: 1fr;
        gap: 20px;
        margin: 40px 0;
    }
    
    .intro-card {
        padding: 25px 20px;
    }
    
    .processing-hub {
        grid-template-columns: 1fr;
        gap: 30px;
        padding: 40px 20px;
    }
    
    .conversion-arrow {
        transform: rotate(90deg);
        margin: 20px 0;
    }
    
    .format-selector {
        flex-direction: column;
        align-items: center;
    }
    
    .format-btn {
        width: 100%;
        max-width: 200px;
    }
    
    .download-btn {
        padding: 16px 40px;
        font-size: 18px;
    }
    
    .upload-area {
        padding: 30px 16px;
    }
    
    .format-section {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }
    
    .select-wrapper {
        width: 100%;
    }
    
    .footer-content {
        flex-direction: column;
        gap: 12px;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 22px;
    }
    
    .upload-icon {
        font-size: 40px;
    }
    
    .upload-area {
        padding: 24px 12px;
    }
}

/* 滚动性能优化 */
/* 懒加载图片样式 */
img[loading="lazy"] {
    opacity: 0;
    transition: opacity 0.3s ease;
}

img.loaded {
    opacity: 1;
}

img.error {
    opacity: 0.5;
    filter: grayscale(100%);
}

/* 滚动动画元素 */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.4s ease-out, transform 0.4s ease-out;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

.slide-up {
    opacity: 0;
    transform: translateY(50px);
    transition: opacity 0.5s ease-out, transform 0.5s ease-out;
}

.slide-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* 桌面端专用样式 */
@media (min-width: 769px) {
    /* 确保logo立即显示 */
    .logo-image {
        opacity: 1 !important;
        visibility: visible !important;
        transition: none !important;
    }
    
    /* 优化桌面端动画速度 */
    .fade-in {
        transition: opacity 0.3s ease-out, transform 0.3s ease-out;
    }
    
    .slide-up {
        transition: opacity 0.4s ease-out, transform 0.4s ease-out;
    }
    
    /* 立即显示关键元素，避免白色过渡 */
    .header,
    .announcement-bar,
    .hero-title,
    .hero-subtitle {
        opacity: 1 !important;
        visibility: visible !important;
        transform: none !important;
    }
    
    /* 核心功能区立即显示 */
    .processing-hub {
        opacity: 1 !important;
        visibility: visible !important;
        transform: none !important;
        animation: none !important;
    }
    
    /* 优化动画性能 */
    .fade-in.visible,
    .slide-up.visible {
        opacity: 1 !important;
        visibility: visible !important;
        transform: translateY(0) !important;
    }
}

/* 滚动性能优化 - 减少重绘和重排 */
.processing-hub,
.intro-card,
.upload-area,
.format-btn,
.convert-btn,
.download-btn {
    will-change: transform;
    contain: layout style paint;
}

/* 移动端滚动优化 */
@media (max-width: 768px) {
    /* 禁用复杂动画以提升滚动性能 */
    .processing-hub::before,
    .processing-hub::after {
        animation: none !important;
    }
    
    .intro-card::before {
        display: none;
    }
    
    /* 优化滚动容器 */
    body {
        -webkit-overflow-scrolling: touch;
        overscroll-behavior: contain;
    }
    
    /* 减少阴影效果 */
    .intro-card,
    .upload-area,
    .processing-hub {
        box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    }
    
    /* 简化过渡效果 */
    .intro-card,
    .upload-area,
    .format-btn,
    .convert-btn,
    .download-btn {
        transition: all 0.2s ease;
    }
}

/* 视差滚动效果（仅桌面端） */
@media (min-width: 769px) {
    [data-parallax] {
        transition: transform 0.1s linear;
    }
}

/* 预加载关键资源 */
.preload-critical {
    contain: strict;
    overflow: hidden;
    position: relative;
}

.preload-critical::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: inherit;
    z-index: 1;
    pointer-events: none;
}

.preload-critical.loaded::after {
    display: none;
}

/* 滚动条样式优化 */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.1);
}

::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.3);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.5);
}

/* 移动端滚动条隐藏 */
@media (max-width: 768px) {
    ::-webkit-scrollbar {
        display: none;
    }
    
    html, body {
        scrollbar-width: none;
        -ms-overflow-style: none;
    }
}