/*
 * 暗色主题基础样式
 * 毛玻璃导航栏、流动背景、按钮、卡片、Footer
 * 各站点通过 :root 变量覆盖调色板
 */

body {
    font-family: var(--font-body);
    line-height: 1.7;
    color: #e2e8f0;
    background: var(--bg-page, #0f172a);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

/* 优雅的淡入效果 */
body > * {
    animation: fadeIn 0.4s ease-out;
}

/* 流动渐变背景（颜色通过 --mesh-bg 覆盖）+ 边缘压暗，制造景深 */
body::before {
    content: '';
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: var(--mesh-bg,
        radial-gradient(ellipse at 20% 50%, rgba(99,102,241,0.12) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 20%, rgba(139,92,246,0.08) 0%, transparent 50%),
        radial-gradient(ellipse at 40% 80%, rgba(6,182,212,0.08) 0%, transparent 50%)),
        radial-gradient(120% 90% at 50% 0%, transparent 55%, rgba(0,0,0,0.45) 100%);
    animation: meshFloat 20s ease-in-out infinite alternate;
    z-index: -2;
    pointer-events: none;
}

/* 点阵网格 + 颗粒纹理（触感层） */
body::after {
    content: '';
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background-image: var(--grain),
        radial-gradient(rgba(255,255,255,0.035) 1px, transparent 1px);
    background-size: 180px 180px, 40px 40px;
    opacity: 0.5;
    mix-blend-mode: overlay;
    z-index: -1;
    pointer-events: none;
}

/* 全站精致滚动条 */
html { scrollbar-color: rgba(255,255,255,0.22) transparent; scrollbar-width: thin; }
::-webkit-scrollbar { width: 11px; height: 11px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, rgba(129,140,248,0.45), rgba(139,92,246,0.35));
    border-radius: 999px;
    border: 3px solid transparent;
    background-clip: padding-box;
}
::-webkit-scrollbar-thumb:hover { background: linear-gradient(180deg, rgba(129,140,248,0.7), rgba(139,92,246,0.55)); background-clip: padding-box; }

@keyframes meshFloat {
    0%   { transform: scale(1) translate(0, 0); }
    33%  { transform: scale(1.05) translate(-2%, 1%); }
    66%  { transform: scale(0.98) translate(1%, -2%); }
    100% { transform: scale(1.02) translate(-1%, 1%); }
}

/* 毛玻璃导航栏：底边发丝 + 顶边内高光（类选择器：裸 header{} 会污染页内 <header>，见 CLAUDE.md 陷阱 26） */
.site-header {
    background: var(--bg-header, rgba(15, 23, 42, 0.8));
    backdrop-filter: blur(20px) saturate(140%);
    -webkit-backdrop-filter: blur(20px) saturate(140%);
    border-bottom: 1px solid var(--hairline);
    box-shadow: inset 0 1px 0 var(--surface-hi), 0 8px 30px -18px rgba(0,0,0,0.6);
    color: white;
    padding: 0.8rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.6rem;
    font-weight: 700;
    background: var(--grad-text);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-decoration: none;
}

nav ul {
    display: flex;
    list-style: none;
    gap: 0.5rem;
}

nav a {
    color: rgba(255,255,255,0.85);
    text-decoration: none;
    transition: color var(--transition-fast), transform var(--transition-fast);
    padding: 0.55rem 0.9rem;
    font-size: 1rem;
    position: relative;
    border-radius: var(--radius-sm);
    min-height: 44px;
    display: inline-flex;
    align-items: center;
}

nav a::after {
    content: '';
    position: absolute;
    bottom: 0; left: 50%; right: 50%;
    height: 2px;
    background: var(--grad-btn);
    transition: left var(--transition-base), right var(--transition-base);
    border-radius: 1px;
}

nav a:hover { color: var(--text-heading, #e0e7ff); }
nav a:hover::after { left: 0; right: 0; }

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

/* 认证组件（导航栏登录/注册/用户下拉） */
.auth-section { display: flex; align-items: center; position: relative; gap: 10px; }
.auth-section .btn-login {
    background: transparent;
    color: rgba(255,255,255,0.85);
    border: 1px solid rgba(255,255,255,0.2);
    padding: 10px 20px;
    min-height: 44px;
    border-radius: 22px;
    text-decoration: none;
    font-size: 14px;
    transition: all var(--transition-base);
    display: inline-flex;
    align-items: center;
}
.auth-section .btn-login:hover {
    background: rgba(255,255,255,0.1);
    border-color: rgba(129,140,248,0.5);
    transform: translateY(-1px);
}
.auth-section .btn-register {
    display: inline-flex;
    align-items: center;
    background: var(--grad-btn);
    color: white;
    border: none;
    padding: 10px 20px;
    min-height: 44px;
    border-radius: 22px;
    text-decoration: none;
    font-size: 14px;
    margin-left: 10px;
    transition: all var(--transition-base);
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.2);
}
.auth-section .btn-register:hover {
    box-shadow: var(--shadow-btn);
    transform: translateY(-1px);
}
.auth-section .user-dropdown-btn {
    display: flex; align-items: center; gap: 8px;
    padding: 6px 16px;
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: 20px;
    background: rgba(255,255,255,0.08);
    cursor: pointer;
    transition: all var(--transition-base);
    color: white;
}
.auth-section .user-dropdown-btn:hover {
    background: rgba(255,255,255,0.15);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}
.auth-section .user-name { color: white; font-size: 14px; }
.auth-section .dropdown-arrow { width: 12px; height: 12px; fill: white; transition: transform var(--transition-base); }
.auth-section .dropdown-menu {
    position: absolute;
    top: calc(100% + 10px); right: 0;
    min-width: 200px;
    background: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    max-height: 70vh;
    overflow-y: auto;
    z-index: 1001;
    padding: 8px 0;
    animation: fadeInScale 0.2s ease-out;
}
.auth-section .dropdown-item {
    padding: 7px 20px; color: #f1f5ff;
    text-decoration: none; display: block;
    transition: all var(--transition-fast);
    border-radius: var(--radius-sm);
    margin: 2px 8px;
}
.auth-section .dropdown-item:hover {
    background: rgba(99,102,241,0.15);
    transform: translateX(2px);
}
.auth-section .dropdown-label {
    padding: 4px 20px 2px; font-size: 11px; color: #94a3b8;
    text-transform: uppercase; letter-spacing: 0.5px; pointer-events: none;
    font-weight: 600;
}
.auth-section .dropdown-divider { height: 1px; background: rgba(255,255,255,0.08); margin: 4px 0; }
.auth-section .btn-logout-dropdown {
    width: 100%; text-align: left; background: none; border: none;
    color: #f87171; cursor: pointer; font-size: 14px; padding: 12px 20px;
    transition: all var(--transition-fast);
    border-radius: var(--radius-sm);
    margin: 2px 8px;
}
.auth-section .btn-logout-dropdown:hover {
    background: rgba(239, 68, 68, 0.1);
    transform: translateX(2px);
}

/* ===== 统一导航下拉菜单 ===== */
.submenu { position: relative; }
.submenu-content {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    background: rgba(22, 30, 48, 0.98);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    min-width: 180px;
    max-height: 70vh;
    overflow-y: auto;
    z-index: 1000;
    border-radius: var(--radius-lg);
    border: 1px solid var(--glass-border);
    padding: 6px 0;
    animation: fadeInScale 0.2s ease-out;
}
.submenu-content a {
    display: block;
    padding: 10px 18px;
    color: #f1f5ff;
    text-decoration: none;
    transition: all var(--transition-fast);
    border-radius: var(--radius-sm);
    margin: 2px 8px;
}
.submenu-content a:hover {
    background: rgba(99,102,241,0.12);
    transform: translateX(3px);
}
.submenu:hover .submenu-content,
.submenu:focus-within .submenu-content {
    display: block;
}

/* ===== 统一卡片组件：实体叠层 + 顶边高光，悬停带品牌辉光 ===== */
.card, .glass-card {
    background:
        linear-gradient(180deg, rgba(255,255,255,0.05), rgba(255,255,255,0.01) 30%, transparent 60%),
        var(--glass-bg);
    backdrop-filter: blur(var(--glass-blur)) saturate(130%);
    -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(130%);
    border: 1px solid var(--hairline);
    border-radius: var(--radius-lg);
    box-shadow: inset 0 1px 0 var(--surface-hi), 0 10px 30px -22px rgba(0,0,0,0.7);
    padding: var(--space-6);
    transition: transform var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
    position: relative;
    overflow: hidden;
}
.card:hover, .glass-card:hover {
    transform: translateY(-5px);
    box-shadow: inset 0 1px 0 var(--surface-hi), 0 18px 40px -20px var(--c-glow, rgba(99,102,241,0.5)), 0 8px 20px -16px rgba(0,0,0,0.8);
    border-color: var(--hairline-strong);
}
.card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 3px;
    background: var(--grad-btn);
    opacity: 0;
    transition: opacity var(--transition-base);
}
.card:hover::before {
    opacity: 1;
}

.card-title, .glass-card h3 {
    color: var(--text-heading, #e0e7ff);
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--space-3);
}

.card-text, .glass-card p {
    color: #b0c4d3;
    line-height: 1.75;
    margin-bottom: var(--space-4);
}

/* ===== 统一按钮样式 ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: 12px 24px;
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: all var(--transition-base);
    border: none;
    position: relative;
    overflow: hidden;
    min-height: 48px;
}

.btn-primary {
    background: var(--grad-btn);
    color: white;
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.25);
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.4);
}
.btn-primary:active {
    transform: translateY(0);
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.3);
}
.btn-primary:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.btn-secondary {
    background: rgba(255,255,255,0.08);
    color: white;
    border: 1px solid rgba(255,255,255,0.2);
}
.btn-secondary:hover {
    background: rgba(255,255,255,0.15);
    border-color: rgba(129,140,248,0.5);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}
.btn-secondary:active {
    transform: translateY(0);
}

.btn-ghost {
    background: transparent;
    color: var(--text-heading, #e0e7ff);
    border: 1px solid transparent;
}
.btn-ghost:hover {
    background: rgba(255,255,255,0.08);
    border-color: rgba(255,255,255,0.15);
}

/* 按钮涟漪效果 */
.btn::after {
    content: '';
    position: absolute;
    top: 50%; left: 50%;
    width: 0; height: 0;
    border-radius: 50%;
    background: rgba(255,255,255,0.3);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}
.btn:active::after {
    width: 300px;
    height: 300px;
}

/* ===== 表单元素 ===== */
input[type="text"],
input[type="email"],
input[type="password"],
input[type="number"],
textarea,
select {
    width: 100%;
    padding: 12px 16px;
    background: var(--form-input-bg);
    border: 1px solid var(--form-input-border);
    border-radius: var(--radius-md);
    color: inherit;
    font-size: 0.95rem;
    transition: all var(--transition-base);
    font-family: inherit;
}

input:focus,
textarea:focus,
select:focus {
    outline: none;
    border-color: var(--c-primary, #6366f1);
    background: var(--form-input-bg-focus);
    box-shadow: 0 0 0 3px rgba(99,102,241,0.1);
}

input::placeholder,
textarea::placeholder {
    color: inherit;
    opacity: 0.65;
}

select option {
    background: #1e293b;
    color: var(--form-text);
}

input:disabled,
textarea:disabled,
select:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    background: rgba(255,255,255,0.03);
}

/* 验证状态 */
input.is-valid,
textarea.is-valid {
    border-color: #10b981;
}
input.is-invalid,
textarea.is-invalid {
    border-color: #ef4444;
}

.form-label {
    display: block;
    color: var(--form-label);
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: var(--space-2);
}

.form-help {
    color: var(--form-help);
    font-size: 0.95rem;
    margin-top: var(--space-1);
}

/* ===== 空状态 ===== */
.empty-state {
    text-align: center;
    padding: var(--space-12) var(--space-6);
    color: #64748b;
}

.empty-state-icon {
    font-size: 4rem;
    margin-bottom: var(--space-4);
    opacity: 0.5;
}

.empty-state-title {
    color: #94a3b8;
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--space-2);
}

.empty-state-text {
    color: #64748b;
    font-size: 0.95rem;
    margin-bottom: var(--space-6);
    max-width: 400px;
    margin-left: auto;
    margin-right: auto;
}

/* ===== 加载状态 ===== */
.loading-spinner {
    display: inline-block;
    width: 24px;
    height: 24px;
    border: 3px solid rgba(99,102,241,0.2);
    border-top-color: var(--c-primary, #6366f1);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.skeleton {
    background: linear-gradient(
        90deg,
        rgba(255,255,255,0.05) 0%,
        rgba(255,255,255,0.1) 50%,
        rgba(255,255,255,0.05) 100%
    );
    background-size: 200% 100%;
    animation: skeleton-loading 1.5s ease-in-out infinite;
    border-radius: var(--radius-sm);
}

@keyframes skeleton-loading {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

.skeleton-text {
    height: 1rem;
    margin-bottom: var(--space-2);
}

.skeleton-title {
    height: 1.5rem;
    width: 60%;
    margin-bottom: var(--space-3);
}

.skeleton-card {
    height: 200px;
    border-radius: var(--radius-lg);
}

/* ===== 排版优化 ===== */
h1, h2, h3, h4, h5, h6 {
    color: var(--text-heading, #e0e7ff);
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: var(--space-4);
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: var(--display-tracking);
}

h2 {
    font-size: 2rem;
    letter-spacing: var(--display-tracking);
}

/* 展示级标题用宋体，立人文质感；正文仍黑体保证可读 */
h1, h2, .display {
    font-family: var(--font-display);
    font-weight: 700;
}

/* 眉题（eyebrow）：小号、宽字距、品牌色，制造排版层级 */
.kicker {
    display: inline-flex;
    align-items: center;
    gap: 0.5em;
    font-family: var(--font-body);
    font-size: 0.74rem;
    font-weight: 600;
    letter-spacing: var(--kicker-tracking);
    text-transform: uppercase;
    color: var(--c-primary, #818cf8);
    padding: 0.4em 0.95em;
    border: 1px solid var(--hairline);
    border-radius: var(--radius-full);
    background: var(--surface-1);
    box-shadow: inset 0 1px 0 var(--surface-hi);
}

/* 统一版块头：眉题 + 标题 + 导语，居左或居中由 .center 控制 */
.section-head { margin-bottom: clamp(2rem, 4vw, 3.2rem); }
.section-head.center { text-align: center; }
.section-head .kicker { margin-bottom: 1rem; }
.section-head h2 { font-size: clamp(1.7rem, 3.4vw, 2.6rem); line-height: 1.2; margin-bottom: 0.7rem; }
.section-head p { color: var(--ui-muted, #94a3b8); font-size: 1.02rem; max-width: 62ch; line-height: 1.75; }
.section-head.center p { margin-left: auto; margin-right: auto; }

h3 {
    font-size: 1.5rem;
}

h4 {
    font-size: 1.25rem;
}

h5 {
    font-size: 1.125rem;
}

h6 {
    font-size: 1rem;
}

p {
    margin-bottom: var(--space-4);
    line-height: 1.7;
}

/* 链接样式 */
a {
    color: var(--c-primary, #6366f1);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--c-primary-dark, #4f46e5);
}

/* 代码样式 */
code {
    background: rgba(99,102,241,0.1);
    color: #c7d2fe;
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    font-family: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;
    font-size: 0.875em;
}

pre {
    background: rgba(15, 23, 42, 0.8);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius-md);
    padding: var(--space-4);
    overflow-x: auto;
    margin-bottom: var(--space-4);
}

pre code {
    background: none;
    padding: 0;
    color: #e2e8f0;
}

/* 引用块 */
blockquote {
    border-left: 4px solid var(--c-primary, #6366f1);
    padding-left: var(--space-4);
    margin: var(--space-6) 0;
    color: #94a3b8;
    font-style: italic;
}

/* 列表样式 */
ul, ol {
    margin-bottom: var(--space-4);
    padding-left: var(--space-6);
}

li {
    margin-bottom: var(--space-2);
    line-height: 1.7;
}

/* 分割线 */
hr {
    border: none;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.15), transparent);
    margin: var(--space-8) 0;
}

/* 强调文本 */
strong, b {
    color: var(--text-heading, #e0e7ff);
    font-weight: 600;
}

em, i {
    font-style: italic;
}

small {
    font-size: 0.875em;
    color: #94a3b8;
}

/* 徽章 */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 4px 12px;
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.02em;
}

.badge-primary {
    background: rgba(99,102,241,0.15);
    color: #818cf8;
}

.badge-success {
    background: rgba(16,185,129,0.15);
    color: #34d399;
}

.badge-warning {
    background: rgba(245,158,11,0.15);
    color: #fbbf24;
}

.badge-danger {
    background: rgba(239,68,68,0.15);
    color: #f87171;
}

/* 工具提示 */
.tooltip {
    position: relative;
    display: inline-block;
}

.tooltip::after {
    content: attr(data-tooltip);
    position: absolute;
    bottom: calc(100% + 8px);
    left: 50%;
    transform: translateX(-50%);
    background: rgba(15, 23, 42, 0.95);
    color: #e2e8f0;
    padding: 6px 12px;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-fast);
    z-index: 1000;
}

.tooltip:hover::after {
    opacity: 1;
}

/* 进度条 */
.progress-bar {
    height: 8px;
    background: rgba(255,255,255,0.1);
    border-radius: var(--radius-full);
    overflow: hidden;
    margin: var(--space-3) 0;
}

.progress-bar-fill {
    height: 100%;
    background: var(--grad-btn);
    border-radius: var(--radius-full);
    transition: width var(--transition-slow);
    position: relative;
}

.progress-bar-fill::after {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: linear-gradient(
        90deg,
        transparent,
        rgba(255,255,255,0.3),
        transparent
    );
    animation: progress-shine 2s ease-in-out infinite;
}

@keyframes progress-shine {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}
/* 自定义滚动条 */
.submenu-content::-webkit-scrollbar { width: 6px; }
.submenu-content::-webkit-scrollbar-track { background: rgba(255,255,255,0.05); border-radius: 3px; }
.submenu-content::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.2); border-radius: 3px; }
.submenu-content::-webkit-scrollbar-thumb:hover { background: rgba(255,255,255,0.3); }
/* 下拉链接 */
.submenu-content a {
    color: rgba(255,255,255,0.8);
    padding: 10px 16px;
    display: block;
    font-size: 0.9rem;
    text-decoration: none;
    white-space: nowrap;
    min-height: 0;              /* 重置 nav a 的 44px 触控下限——下拉项不需要，否则 AI工具多列面板被撑高触发滚动条 */
    transition: background 0.15s;
}
.submenu-content a:hover {
    background: rgba(99,102,241,0.15);
    color: #c7d2fe;
}
.submenu-content a::after { display: none; }
/* 下拉显隐/布局规则的唯一来源（hover + focus-within 对等，点击/键盘聚焦也能展开）。
   ⚠️ 站点 CSS 勿再写 .submenu 显隐覆写——高特异性重复规则曾把 AI工具 4 列面板压成单列
   （subdomain-common.css 旧 .header-content .submenu:focus-within{display:block}，见 CLAUDE.md 陷阱 27） */
.submenu:hover > .submenu-content,
.submenu:focus-within > .submenu-content { display: block; }

/* 频道下拉双列 */
.channels-submenu .submenu-content {
    min-width: 380px;
    display: none;
    grid-template-columns: 1fr 1fr;
}
.channels-submenu:hover > .submenu-content,
.channels-submenu:focus-within > .submenu-content { display: grid; }

/* AI工具 下拉分组面板（分栏布局：全高展示、正常屏幕不出内部滚动条；
   覆盖基类 70vh 上限——仅当视口比菜单还矮时才兜底滚动，避免第三栏 15+ 链接在笔记本屏触发竖向滚动条） */
.tools-submenu .submenu-content {
    min-width: 640px;
    max-width: 94vw;
    left: 50%;
    transform: translateX(-50%);
    display: none;
    flex-wrap: wrap;
    gap: 0 4px;
    padding: 6px 6px 8px;
    max-height: calc(100vh - 72px);
    overflow-y: auto;
}
.tools-submenu:hover > .submenu-content,
.tools-submenu:focus-within > .submenu-content { display: flex; }
/* 更多 下拉分组面板（分栏布局同 AI工具；面板右对齐触发项，防末位菜单撑出视口右缘） */
.more-submenu .submenu-content {
    min-width: 680px;
    max-width: 94vw;
    left: auto;
    right: 0;
    display: none;
    flex-wrap: wrap;
    gap: 0 4px;
    padding: 6px 6px 8px;
    max-height: calc(100vh - 72px);
    overflow-y: auto;
}
.more-submenu:hover > .submenu-content,
.more-submenu:focus-within > .submenu-content { display: flex; }
/* 分栏列/组标签/链接样式：AI工具与「更多」两个分栏面板共享 */
.tools-submenu .mega-col,
.more-submenu .mega-col {
    flex: 1 1 150px;
    min-width: 150px;
    padding: 2px 6px;
}
.tools-submenu .mega-col + .mega-col,
.more-submenu .mega-col + .mega-col { border-left: 1px solid rgba(255,255,255,0.06); }
.tools-submenu .nav-group-label,
.more-submenu .nav-group-label {
    font-size: 0.68rem;
    font-weight: 600;
    color: rgba(255,255,255,0.7);
    letter-spacing: 0.04em;
    padding: 6px 10px 2px;
}
.tools-submenu .nav-group-label.nav-group-mt,
.more-submenu .nav-group-label.nav-group-mt { margin-top: 4px; }
.tools-submenu .submenu-content a,
.more-submenu .submenu-content a {
    margin: 1px 4px;
    padding: 6px 10px;
    font-size: 0.85rem;
    line-height: 1.25;
    white-space: nowrap;
}
.nav-tag {
    font-size: 0.62rem;
    background: rgba(16,185,129,0.15);
    padding: 1px 6px;
    border-radius: 4px;
    margin-left: 3px;
}
.nav-hl-amber { color: #fbbf24 !important; }
.nav-hl-green { color: #34d399 !important; }
.nav-hl-blue  { color: #60a5fa !important; }
.nav-hl-indigo{ color: #818cf8 !important; }
.nav-hl-pink  { color: #f472b6 !important; }
.nav-hl-violet{ color: #a78bfa !important; }
.nav-hl-red   { color: #fca5a5 !important; font-weight: 600; }
.tools-submenu .nav-hl-amber,
.more-submenu .nav-hl-amber { font-weight: 500; }

@media (max-width: 768px) {
    .channels-submenu .submenu-content {
        min-width: 280px;
        grid-template-columns: 1fr;
    }
    .channels-submenu:hover > .submenu-content { display: block; }
}

/* 渐变按钮：内高光 + 悬停高光扫过 */
.btn {
    display: inline-block;
    background: var(--grad-btn);
    color: white;
    padding: 14px 32px;
    text-decoration: none;
    border-radius: var(--radius-btn);
    border: 1px solid rgba(255,255,255,0.18);
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    letter-spacing: 0.01em;
    transition: transform 0.25s cubic-bezier(.34,1.56,.64,1), box-shadow 0.25s, filter 0.25s;
    box-shadow: var(--shadow-btn), inset 0 1px 0 rgba(255,255,255,0.28), inset 0 -1px 0 rgba(0,0,0,0.18);
    position: relative;
    overflow: hidden;
}

.btn::after {
    content: '';
    position: absolute;
    top: 0; left: -120%;
    width: 60%; height: 100%;
    background: linear-gradient(100deg, transparent, rgba(255,255,255,0.35), transparent);
    transform: skewX(-20deg);
    transition: left 0.6s ease;
    pointer-events: none;
}

.btn:hover {
    transform: translateY(-2px);
    filter: saturate(1.1);
    box-shadow: 0 10px 30px var(--c-glow, rgba(99,102,241,0.5)), inset 0 1px 0 rgba(255,255,255,0.32);
}
.btn:hover::after { left: 130%; }
.btn:active { transform: translateY(0); }

/* 渐变标题 */
.section-title {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 3rem;
    background: var(--grad-text);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 700;
}

/* Footer */
footer {
    background: var(--bg-footer, rgba(15, 23, 42, 0.5));
    border-top: 1px solid var(--glass-border);
    color: #94a3b8;
    text-align: center;
    padding: 2rem 0;
    margin-top: 3rem;
}
footer p { color: #94a3b8; }

/* ===== 滚动揭示动效：默认隐藏，JS 进入视口时加 .in ===== */
[data-reveal] {
    opacity: 0;
    transform: translateY(26px);
    transition: opacity 0.7s cubic-bezier(0.22, 0.61, 0.36, 1), transform 0.7s cubic-bezier(0.22, 0.61, 0.36, 1);
    transition-delay: var(--reveal-delay, 0s);
    will-change: opacity, transform;
}
[data-reveal].in { opacity: 1; transform: none; }

/* 缓入视差辉光（用于首屏装饰） */
@keyframes floaty {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-12px); }
}
.floaty { animation: floaty 6s ease-in-out infinite; }

/* 响应式 */
@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
    }
    nav ul {
        margin-top: 0.8rem;
        justify-content: center;
        flex-wrap: wrap;
    }
    nav li {
        margin: 0;
    }
}

/* ====== 移动端导航：汉堡菜单 + 侧滑抽屉 ====== */

.hamburger-btn {
    position: relative;
    z-index: 1010;
    display: none;
    background: none;
    border: none;
    color: white;
    font-size: 24px;
    cursor: pointer;
    padding: 10px 14px;
    min-height: 44px;
    min-width: 44px;
    border-radius: 8px;
    transition: background 0.2s;
    line-height: 1;
}
.hamburger-btn:hover { background: rgba(255,255,255,0.1); }
.hamburger-btn span {
    display: block;
    width: 22px;
    height: 2px;
    background: white;
    margin: 5px 0;
    transition: all 0.3s;
    border-radius: 1px;
}

.mobile-nav-overlay {
    display: none;
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(0,0,0,0.6);
    /* 层叠契约：必须 < .site-header(z:100)。抽屉 nav 在 header 内，被
       sticky 层叠上下文困在 z=100；遮罩若 >=100 会盖住整个抽屉，致
       下拉项文字蒙黑看不清（2026-08-24 修复；回归源于 7月8日
       bf6a345 把 header 从 1000 降到 100 未同步遮罩） */
    z-index: 90;
    opacity: 0;
    transition: opacity 0.3s;
    pointer-events: none;
}
.mobile-nav-overlay.active { display: block; opacity: 1; pointer-events: none; }

/* 移动端关闭按钮默认隐藏，仅在 768px 以下显示 */
.mobile-nav-close {
    display: none;
}

@media (max-width: 768px) {
    .hamburger-btn { display: block; }
    .site-header { padding: 0 !important; }
    .site-header .header-content { min-height: 44px; }
    .header-content {
        flex-direction: row !important;
        flex-wrap: nowrap !important;
        justify-content: space-between !important;
        align-items: center !important;
        padding: 0 12px !important;
    }
    .logo { font-size: 1.2rem !important; }
    nav {
        position: fixed;
        top: 0;
        right: 0;
        width: 280px;
        height: 100vh;
        background: rgba(15, 23, 42, 0.98);
        backdrop-filter: blur(20px);
        -webkit-backdrop-filter: blur(20px);
        z-index: 200;
        overflow-y: auto;
        padding: 60px 0 20px;
        border-left: 1px solid rgba(255,255,255,0.08);
        /* 关闭态留在视口内(right:0)，用 clip-path+visibility 隐藏抽屉：
           旧写法 right:-300px 会把 fixed 盒推到 ICB 之外，撑出移动端横向滚动；
           也不能在根元素加 overflow-x:hidden/clip（实测会破坏 sticky 顶栏）。
           visibility:hidden 顺带把离屏链接移出 Tab 顺序，改善可访问性。 */
        clip-path: inset(0 0 0 100%);
        visibility: hidden;
        pointer-events: none;
        transition: clip-path 0.3s ease, visibility 0s linear 0.3s;
    }
    nav.mobile-nav-open {
        clip-path: inset(0 0 0 0);
        visibility: visible;
        pointer-events: auto;
        transition: clip-path 0.3s ease, visibility 0s;
    }
    nav ul {
        flex-direction: column !important;
        gap: 0 !important;
        margin-top: 0 !important;
        flex-wrap: nowrap !important;
        justify-content: flex-start !important;
    }
    nav li { margin: 0 !important; border-bottom: 1px solid rgba(255,255,255,0.05); }
    nav a { display: block; padding: 14px 24px !important; font-size: 15px !important; }
    nav a::after { display: none !important; }
    .submenu-content {
        position: static !important;
        background: rgba(15, 23, 42, 0.5) !important;
        backdrop-filter: none !important;
        border: none !important;
        border-radius: 0 !important;
        box-shadow: none !important;
        min-width: auto !important;
        max-height: none !important;
        display: none !important;
        /* AI工具大面板桌面端靠 left:50%+translateX(-50%) 居中；position:static 只废掉 left，
           transform 不清则整个面板左移自身宽度一半、左半链接裁出抽屉且滚不回来（"显示不全"主因） */
        transform: none !important;
        left: auto !important;
    }
    .submenu.open .submenu-content { display: block !important; }
    .submenu-content a { padding: 10px 40px !important; font-size: 14px !important; }
    .channels-submenu .submenu-content {
        grid-template-columns: 1fr !important;
        display: none !important;
    }
    .channels-submenu.open .submenu-content { display: block !important; }
    .mobile-nav-close {
        display: block;
        position: absolute;
        top: 12px;
        right: 12px;
        background: rgba(255,255,255,0.1);
        border: none;
        color: white;
        font-size: 24px;
        cursor: pointer;
        padding: 10px 14px;
        min-width: 44px;
        min-height: 44px;
        line-height: 1;
        border-radius: 8px;
        z-index: 10;
    }
    .auth-section { margin-top: 0 !important; }
    body { padding-bottom: 0; }
}

@media (max-width: 480px) {
    .logo { font-size: 1.1rem !important; }
    nav { width: 260px; }
}

/* 移动端下拉菜单：JS 点击切换 .open 状态（.open 仅移动端 JS 置，桌面端走 hover，
   故以下规则实际只在窄屏生效，无需再包 media query） */
.submenu.open .submenu-content { display: block; }
.channels-submenu.open .submenu-content { display: grid; }
/* 分栏大面板移动端（AI工具 + 更多）：废弃双列——抽屉仅 260-280px，双列每列 110px、
   叠 40px 水平 padding + nowrap 把链接文字压到 ~30px 硬裁。改单列竖排 + 允许换行，
   链接全宽完整展示，列表长度交给抽屉自身滚动消化（与其他下拉的竖排范式一致） */
.tools-submenu.open .submenu-content,
.more-submenu.open .submenu-content { display: block !important; }
.tools-submenu.open .mega-col,
.more-submenu.open .mega-col { width: 100%; min-width: 0; border-left: none; padding: 4px 0; }
.tools-submenu.open .mega-col + .mega-col,
.more-submenu.open .mega-col + .mega-col { border-top: 1px solid rgba(255,255,255,0.07); margin-top: 2px; padding-top: 6px; }
.tools-submenu.open .submenu-content a,
.more-submenu.open .submenu-content a {
    display: block;
    white-space: normal;
    margin: 1px 10px;
    padding: 10px 14px 10px 22px !important;
    font-size: 13.5px !important;
    line-height: 1.4;
    border-radius: 8px;
}
.tools-submenu.open .nav-group-label,
.more-submenu.open .nav-group-label { padding: 8px 22px 3px; }

/* AI 工具结果温馨提示 */
.ai-caution-note { text-align: center; padding: 10px 16px; font-size: 0.85rem; color: rgba(255,255,255,0.55); margin-top: 12px; border-top: 1px solid rgba(255,255,255,0.08); line-height: 1.6; }

/* ===== 无障碍增强 ===== */

/* 大字模式：整体放大但不破坏布局 */
html.a11y-large-text body { font-size: 1.05rem; }
html.a11y-large-text .btn { min-height: 52px; padding: 14px 28px; font-size: 1.05rem; }
html.a11y-large-text nav a { min-height: 48px; font-size: 1.05rem; }
html.a11y-large-text .form-label { font-size: 1rem; }
html.a11y-large-text .form-help { font-size: 1rem; }
html.a11y-large-text .card-title { font-size: 1.35rem; }

/* 高对比模式：实色替代渐变文字，加深背景，加粗边框 */
html.a11y-high-contrast .logo,
html.a11y-high-contrast .section-title {
    -webkit-text-fill-color: #e0e7ff;
    background: none;
    color: #e0e7ff;
}
html.a11y-high-contrast .card,
html.a11y-high-contrast .glass-card,
html.a11y-high-contrast .service-item,
html.a11y-high-contrast .info-item {
    background: rgba(255,255,255,0.12);
    border: 1px solid rgba(255,255,255,0.25);
}
html.a11y-high-contrast .card-text,
html.a11y-high-contrast .glass-card p,
html.a11y-high-contrast .service-item p,
html.a11y-high-contrast .info-item p,
html.a11y-high-contrast footer p {
    color: #e2e8f0;
}
html.a11y-high-contrast nav a { color: #ffffff; }
html.a11y-high-contrast .btn-primary { color: #ffffff; border: 1px solid #ffffff; }
html.a11y-high-contrast .btn-secondary { color: #ffffff; border: 1px solid rgba(255,255,255,0.45); }
html.a11y-high-contrast input,
html.a11y-high-contrast textarea,
html.a11y-high-contrast select {
    border-width: 2px;
}
html.a11y-high-contrast input:focus,
html.a11y-high-contrast textarea:focus,
html.a11y-high-contrast select:focus {
    box-shadow: 0 0 0 4px rgba(99,102,241,0.35);
}
html.a11y-high-contrast *:focus-visible {
    outline: 3px solid #818cf8;
    outline-offset: 3px;
}
html.a11y-high-contrast .badge { border: 1px solid currentColor; }

/* 减少动效 */
html.a11y-reduce-motion *,
html.a11y-reduce-motion *::before,
html.a11y-reduce-motion *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
}