/* 基础样式重置 */
* {
    box-sizing: border-box;
}

body {
    margin: 0;
    padding: 10px;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
}

/* 头部样式 */
.header-div {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    margin: 0 auto 20px auto;
    padding: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    max-width: 1200px;
    overflow: hidden;
}

/* 导航栏样式 */
.navbar {
    width: 100%;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 60px;
    position: relative;
}

.nav-menu {
    display: flex;
    gap: 4px;
    flex-wrap: nowrap;
    align-items: center;
    justify-content: center;
    width: 100%;
    position: relative;
}

.nav-link {
    color: white;
    text-decoration: none;
    padding: 4px 1px;
    background-color: rgba(255, 255, 255, 0.15);
    border-radius: 12px;
    transition: all 0.3s ease;
    font-size: 0.75rem;
    white-space: nowrap;
    flex: 1;
    text-align: center;
    min-width: 0;
    display: block;
}

.nav-link:hover {
    background-color: rgba(255, 255, 255, 0.25);
    transform: translateY(-1px);
}

/* 汉堡菜单按钮样式 */
.nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-around;
    width: 30px;
    height: 30px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 1001;
}

/* PC端隐藏关闭按钮和菜单头部 */
.nav-close-btn {
    display: none;
}

.nav-menu-header {
    display: none;
}

.hamburger {
    width: 25px;
    height: 3px;
    background-color: white;
    border-radius: 2px;
    transition: all 0.3s ease;
    transform-origin: center;
}

.nav-toggle-active .hamburger:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle-active .hamburger:nth-child(2) {
    opacity: 0;
}

.nav-toggle-active .hamburger:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* 移动端菜单遮罩层 */
.nav-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 999;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    display: none;
}

.nav-overlay-active {
    opacity: 1;
    visibility: visible;
    display: block;
}


.header-title {
    margin: 20px 0;
    font-size: 2rem;
    font-weight: 700;
    text-align: center;
    padding: 0 20px;
}

/* 主内容区域 */
.main-div {
    display: flex;
    gap: 20px;
    max-width: 1200px;
    margin: 0 auto;
}

.frame-div {
    flex: 1;
    background: white;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    overflow: hidden;
}

.frame-top {
    padding: 15px;
    background-color: #f8f9fa;
    border-bottom: 1px solid #e9ecef;
}

.frame-center {
    min-height: 300px;
    padding: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

/* 文件上传区域 */
.file-label {
    display: inline-block;
    padding: 10px 20px;
    background-color: #007bff;
    color: white;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s ease;
    font-weight: 500;
}

.file-label:hover {
    background-color: #0056b3;
}

#fileBtn {
    display: none;
}

/* 控制区域 */
.controls-group {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-bottom: 15px;
}

.range-label {
    font-weight: 500;
    color: #495057;
}

#rangeInput {
    width: 100%;
    height: 6px;
    border-radius: 3px;
    background: #ddd;
    outline: none;
    -webkit-appearance: none;
}

#rangeInput::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: #007bff;
    cursor: pointer;
}

#rangeInput::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: #007bff;
    cursor: pointer;
    border: none;
}

.download-btn {
    width: 100%;
    padding: 12px 20px;
    background-color: #28a745;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    font-weight: 500;
    transition: background-color 0.3s ease;
}

.download-btn:hover {
    background-color: #218838;
}

.download-btn:disabled {
    background-color: #6c757d;
    cursor: not-allowed;
}

/* 图片样式 */
img {
    max-width: 100%;
    max-height: 400px;
    height: auto;
    border-radius: 5px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

/* 占位符文本 */
.placeholder-text {
    color: #6c757d;
    font-style: italic;
    text-align: center;
    padding: 40px 20px;
}

/* 语言切换链接 */
center {
    margin-top: 20px;
    padding: 20px;
}

center a {
    color: #007bff;
    text-decoration: none;
    margin: 0 10px;
    padding: 5px 10px;
    border-radius: 3px;
    transition: background-color 0.3s ease;
}

center a:hover {
    background-color: #e9ecef;
}

/* 响应式设计 */
@media screen and (max-width: 1024px) {
    .nav-menu {
        gap: 3px;
    }
    
    .nav-link {
        padding: 3px 5px;
        font-size: 0.7rem;
    }
}

/* PC端导航菜单样式重置 */
@media screen and (min-width: 769px) {
    .nav-menu {
        position: static;
        left: auto;
        width: 100%;
        height: auto;
        background: transparent;
        flex-direction: row;
        justify-content: center;
        align-items: center;
        padding: 0;
        gap: 4px;
        box-shadow: none;
        overflow: visible;
    }
    
    .nav-link {
        padding: 4px 1px;
        font-size: 0.75rem;
        border-radius: 12px;
        text-align: center;
        flex: 1;
        min-width: 0;
        background-color: rgba(255, 255, 255, 0.15);
        color: white;
        border: none;
        margin-bottom: 0;
        transition: all 0.3s ease;
        box-shadow: none;
        font-weight: normal;
        display: block;
        text-decoration: none;
    }
    
    .nav-link:hover {
        background-color: rgba(255, 255, 255, 0.25);
        transform: translateY(-1px);
        color: white;
        box-shadow: none;
    }
    
    .nav-close-btn {
        display: none !important;
    }
    
    .nav-menu-header {
        display: none !important;
    }
}

/* 统一为所有页面的导航项添加图标（无需改各页面HTML） */
.nav-link::before {
    display: inline-block;
    margin-right: 0; /* 与文字紧贴 */
    font-size: 16px;
    line-height: 1;
}
.nav-link[href$="index.html"]::before { content: "🧩"; }
.nav-link[href$="crop.html"]::before { content: "✂️"; }
.nav-link[href$="convert.html"]::before { content: "🗂️"; }
.nav-link[href$="icon.html"]::before { content: "🧩"; }
.nav-link[href$="compress.html"]::before { content: "🗜️"; }
.nav-link[href$="blank.html"]::before { content: "🌓"; }
.nav-link[href$="watermark.html"]::before { content: "💧"; }
.nav-link[href$="removewm.html"]::before { content: "🧼"; }
.nav-link[href$="nine.html"]::before { content: "⊞"; color: #007bff; }
.nav-link[href$="text.html"]::before { content: "🔤"; }
.nav-link[href$="join.html"]::before { content: "🧱"; }
.nav-link[href$="textToimage.html"]::before { content: "🖊️"; }
.nav-link[href$="corner.html"]::before { content: "◻️"; }
.nav-link[href$="expand.html"]::before { content: "🔍"; }
.nav-link[href$="old.html"]::before { content: "🖼️"; }
.nav-link[href$="bg.html"]::before { content: "🎨"; }
.nav-link[href$="removebg.html"]::before { content: "🪄"; }
.nav-link[href$="changebg.html"]::before { content: "🌄"; }

/* 底部统一版权（所有页面生效） */
body::after {
    content: "Copyright © Chuandao AI";
    display: block;
    text-align: center;
    color: #999;
    font-size: 14px;
    margin-top: 20px;
    padding: 10px 0;
}

@media screen and (max-width: 768px) {
    body {
        padding: 5px;
    }
    
    .header-div {
        margin: 0 auto 15px auto;
    }
    
    .nav-container {
        padding: 0 15px;
        height: 50px;
        justify-content: space-between;
    }
    
    /* 显示汉堡菜单按钮 */
    .nav-toggle {
        display: flex;
    }
    
    /* 隐藏PC端菜单 */
    .nav-menu {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        width: 320px;
        height: 100vh;
        background: #ffffff;
        flex-direction: column;
        justify-content: flex-start;
        align-items: stretch;
        padding: 0;
        gap: 0;
        z-index: 10001;
        box-shadow: 2px 0 10px rgba(0, 0, 0, 0.1);
        overflow-y: auto;
        -webkit-overflow-scrolling: touch;
        transform: translateX(-100%);
        transition: transform .25s ease;
    }
    /* 防止父级裁剪/新层叠上下文导致抽屉被遮挡 */
    .header-div, .navbar, .nav-container { overflow: visible !important; }
    .header-div, .navbar, .nav-container { transform: none !important; -webkit-transform: none !important; }
    .header-div, .navbar, .nav-container { contain: unset !important; }
    
    .header-title {
        font-size: 1.5rem;
        margin: 15px 0;
    }
    
    .main-div {
        flex-direction: column;
        gap: 15px;
    }
    
    .frame-center {
        min-height: 250px;
    }
    
    .controls-group {
        flex-direction: row;
        align-items: center;
        gap: 15px;
    }
    
    .range-label {
        white-space: nowrap;
        min-width: 120px;
    }
    
    #rangeInput {
        flex: 1;
    }
}

@media screen and (max-width: 480px) {
    .header-div {
        padding: 0;
    }
    
    .nav-container {
        padding: 0 10px;
        height: 45px;
    }
    
    .nav-menu {
        width: 90%;
        max-width: 320px;
    }
    
    .nav-menu-title {
        padding: 16px;
        font-size: 1rem;
    }
    
    .nav-link {
        padding: 16px 18px;
        font-size: 0.95rem;
    }
    
    .header-title {
        font-size: 1.3rem;
        margin: 12px 0;
        padding: 0 15px;
    }
    
    .frame-top {
        padding: 10px;
    }
    
    .frame-center {
        min-height: 200px;
        padding: 10px;
    }
    
    .controls-group {
        flex-direction: column;
        align-items: stretch;
    }
    
    .range-label {
        min-width: auto;
    }
    
    .file-label, .download-btn {
        padding: 12px 16px;
        font-size: 14px;
    }
}


/* 移动端菜单样式 - 当菜单激活时显示 */
@media screen and (max-width: 768px) {
    /* 使用 html 锁定滚动，避免影响内部 fixed 容器滚动 */
    
    html.menu-open {
        overflow: hidden !important;
    }
    .nav-menu-active {
        display: block !important;
        position: fixed !important;
        top: 0 !important;
        left: 0 !important;
        width: 320px !important;
        height: calc(100vh - 48px) !important;
        background: #ffffff !important;
        padding: 0 !important;
        z-index: 10001 !important;
        box-shadow: 2px 0 10px rgba(0, 0, 0, 0.1) !important;
        overflow-y: auto !important;
        overflow-x: hidden !important;
        overflow-x: hidden !important;
        -webkit-overflow-scrolling: touch !important;
        transform: translateX(0) !important;
        touch-action: pan-y !important;
        overscroll-behavior: contain !important;
    }
    
    .nav-menu-active .nav-menu-title {
        padding: 20px;
        background: #f8f9fa;
        color: #333;
        font-size: 1.1rem;
        font-weight: 600;
        text-align: center;
        margin: 0;
        border-bottom: 2px solid #e9ecef;
    }
    
    .nav-menu-active .nav-link {
        padding: 16px 20px;
        font-size: 1rem;
        border-radius: 0;
        text-align: left;
        flex: none;
        min-width: auto;
        background-color: white;
        color: #333;
        border-bottom: 1px solid #f0f0f0;
        margin: 0;
        transition: background-color 0.2s ease;
        box-shadow: none;
        font-weight: 500;
        display: block;
        text-decoration: none;
        width: 100%;
        box-sizing: border-box;
        min-height: 50px;
        line-height: 1.2;
    }
    /* 确保移动端菜单显示图标，并与文字保持间距 */
    .nav-menu-active .nav-link::before {
        display: inline-block;
        font-size: 16px;
        margin-right: 8px;
    }
    
    .nav-menu-active .nav-link[href$="nine.html"]::before {
        color: #007bff;
    }
    
    .nav-menu-active .nav-link:hover {
        background-color: #f8f9fa;
        color: #007bff;
    }
    
    .nav-menu-active .nav-link:active {
        background-color: #e9ecef;
        color: #0056b3;
    }
    
    /* 确保遮罩层在移动端正确显示 */
    .nav-overlay-active {
        display: block !important;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: rgba(0, 0, 0, 0.5);
        z-index: 10000;
    }
}

/* 大屏幕优化 */
@media screen and (min-width: 1200px) {
    .main-div {
        gap: 30px;
    }
    
    .frame-center {
        min-height: 400px;
    }
}

/* 与 index.html 保持一致的桌面端宽度策略 */
@media screen and (min-width: 1025px) {
    html, body { min-width: 1600px; }
    .header-div, .nav-container, .main-div, .main-container { max-width: none !important; }
}