/* ========================================
   UI Polish - 全局 UI 优化样式
   按照 UI 设计师标准完善
   ======================================== */

/* ========== 1. 全局优化 ========== */

/* 更平滑的滚动 */
html {
    scroll-behavior: smooth;
}

/* 优化字体渲染 */
body {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

/* 选中文本样式 */
::selection {
    background: rgba(99, 102, 241, 0.3);
    color: #fff;
}

::-moz-selection {
    background: rgba(99, 102, 241, 0.3);
    color: #fff;
}

/* ========== 2. 按钮优化 ========== */

/* 统一按钮基础样式 */
button {
    font-family: inherit;
    cursor: pointer;
    user-select: none;
    -webkit-tap-highlight-color: transparent;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

button:active {
    transform: scale(0.98);
}

button:disabled {
    cursor: not-allowed;
    opacity: 0.5;
}

/* 主按钮增强 */
.glass-btn.primary {
    position: relative;
    overflow: hidden;
}

.glass-btn.primary::before {
    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;
}

.glass-btn.primary:hover::before {
    width: 300px;
    height: 300px;
}

/* 图标按钮优化 */
.icon-btn {
    position: relative;
    overflow: hidden;
}

.icon-btn::after {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
    opacity: 0;
    transition: opacity 0.3s;
}

.icon-btn:hover::after {
    opacity: 1;
}

/* ========== 3. 卡片优化 ========== */

/* 卡片阴影层次 */
.card-face {
    box-shadow:
        0 1px 3px rgba(0, 0, 0, 0.12),
        0 1px 2px rgba(0, 0, 0, 0.24),
        0 10px 40px rgba(0, 0, 0, 0.3);
}

.card-face:hover {
    box-shadow:
        0 14px 28px rgba(0, 0, 0, 0.25),
        0 10px 10px rgba(0, 0, 0, 0.22),
        0 20px 60px rgba(0, 0, 0, 0.4);
}

/* 卡片内容对齐优化 */
.card-back {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    padding: 2rem;
}

.word-title {
    letter-spacing: 0.5px;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

.meaning {
    letter-spacing: 0.3px;
    line-height: 1.5;
}

.example {
    line-height: 1.7;
    letter-spacing: 0.2px;
}

/* ========== 4. 输入框优化 ========== */

input[type="text"],
input[type="password"],
textarea,
select {
    font-family: inherit;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

input:focus,
textarea:focus,
select:focus {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.2);
}

/* 搜索框增强 */
#search-input {
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

#search-input:focus {
    transform: scale(1.02);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

/* ========== 5. 模态框优化 ========== */

.modal {
    -webkit-backdrop-filter: blur(12px) saturate(180%);
    backdrop-filter: blur(12px) saturate(180%);
}

.modal.active {
    animation: modalFadeIn 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes modalFadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

.modal-content {
    animation: modalSlideUp 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

@keyframes modalSlideUp {
    from {
        opacity: 0;
        transform: translateY(30px) scale(0.95);
    }

    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

/* ========== 6. 导航优化 ========== */

.tabs-container {
    position: relative;
}

/* Tab 指示器 */
.tabs-container::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    height: 3px;
    background: var(--primary);
    border-radius: 3px 3px 0 0;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.tab-btn {
    position: relative;
    z-index: 1;
}

/* ========== 7. 加载状态 ========== */

@keyframes shimmer {
    0% {
        background-position: -1000px 0;
    }

    100% {
        background-position: 1000px 0;
    }
}

.loading-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: 1000px 100%;
    animation: shimmer 2s infinite;
}

/* ========== 8. 滚动条优化 ========== */

::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 10px;
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, var(--primary), var(--accent));
    border-radius: 10px;
    border: 2px solid rgba(255, 255, 255, 0.1);
}

::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(180deg, var(--primary-light), var(--accent));
}

/* Firefox 滚动条 */
@supports (scrollbar-width: thin) {
    * {
        scrollbar-width: thin;
        scrollbar-color: var(--primary) rgba(255, 255, 255, 0.05);
    }
}

/* ========== 9. 动画优化 ========== */

/* 淡入动画 */
@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

/* 滑入动画 */
@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 缩放动画 */
@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.9);
    }

    to {
        opacity: 1;
        transform: scale(1);
    }
}

/* 应用动画到元素 */
.fade-in {
    animation: fadeIn 0.5s ease-out;
}

.slide-in-up {
    animation: slideInUp 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.scale-in {
    animation: scaleIn 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* ========== 10. 响应式优化 ========== */

/* 移动端触摸优化 */
@media (hover: none) and (pointer: coarse) {
    button {
        min-height: 44px;
        min-width: 44px;
    }

    .card-container {
        cursor: default;
    }

    /* 移除 hover 效果 */
    .card:hover {
        transform: none;
    }
}

/* 平板优化 */
@media (min-width: 768px) and (max-width: 1024px) {
    .grid {
        grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
        gap: 2rem;
    }
}

/* 大屏优化 */
@media (min-width: 1920px) {
    .container {
        max-width: 1600px;
    }

    .grid {
        grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
        gap: 3.5rem;
    }
}

/* ========== 11. 微交互优化 ========== */

/* 按钮点击反馈 */
@keyframes buttonPress {
    0% {
        transform: scale(1);
    }

    50% {
        transform: scale(0.95);
    }

    100% {
        transform: scale(1);
    }
}

button:active:not(:disabled) {
    animation: buttonPress 0.2s ease-out;
}

/* 卡片翻转优化 */
.card.is-flipped {
    animation: cardFlip 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes cardFlip {
    0% {
        transform: rotateY(0deg);
    }

    100% {
        transform: rotateY(180deg);
    }
}

/* ========== 12. 焦点优化 ========== */

/* 自定义焦点样式 */
*:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 3px;
    border-radius: 4px;
}

/* 移除默认焦点 */
*:focus:not(:focus-visible) {
    outline: none;
}

/* ========== 13. 加载指示器 ========== */

.loading-dots {
    display: inline-flex;
    gap: 4px;
}

.loading-dots span {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: currentColor;
    animation: loadingDot 1.4s infinite ease-in-out both;
}

.loading-dots span:nth-child(1) {
    animation-delay: -0.32s;
}

.loading-dots span:nth-child(2) {
    animation-delay: -0.16s;
}

@keyframes loadingDot {

    0%,
    80%,
    100% {
        transform: scale(0);
        opacity: 0.5;
    }

    40% {
        transform: scale(1);
        opacity: 1;
    }
}

/* ========== 14. 徽章优化 ========== */

.badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 20px;
    height: 20px;
    padding: 0 6px;
    font-size: 0.7rem;
    font-weight: 700;
    line-height: 1;
    border-radius: 10px;
    animation: badgePop 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

@keyframes badgePop {
    0% {
        transform: scale(0);
    }

    100% {
        transform: scale(1);
    }
}

/* ========== 15. 工具提示优化 ========== */

[title] {
    position: relative;
}

/* 自定义 tooltip */
.tooltip {
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%) translateY(-8px);
    padding: 6px 12px;
    background: rgba(0, 0, 0, 0.9);
    color: white;
    font-size: 0.75rem;
    border-radius: 6px;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s, transform 0.2s;
    z-index: 1000;
}

.tooltip::after {
    content: '';
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    border: 4px solid transparent;
    border-top-color: rgba(0, 0, 0, 0.9);
}

*:hover>.tooltip {
    opacity: 1;
    transform: translateX(-50%) translateY(-4px);
}

/* ========== 16. 打印样式优化 ========== */

@media print {
    body {
        background: white;
        color: black;
    }

    .card-face {
        border: 1px solid #ccc;
        box-shadow: none;
        page-break-inside: avoid;
    }

    button,
    .header-actions,
    .pagination-container {
        display: none !important;
    }
}

/* ========== 17. 性能优化 ========== */

/* GPU 加速 - 已裁剪 translateZ(0) 以防破坏 3D 嵌套 */
.card,
.modal-content,
.glass-btn {
    will-change: transform;
}

/* 减少重绘 */
.card-container {
    /* contain: layout style paint; - 移除,可能导致布局问题 */
}

/* ========== 18. 暗色模式增强 ========== */

@media (prefers-color-scheme: dark) {

    /* 已经是暗色，增强对比度 */
    :root {
        --text-main: #ffffff;
        --text-muted: #a0aec0;
    }
}

/* ========== 19. 辅助类 ========== */

.text-gradient {
    background: linear-gradient(135deg, var(--primary-light), var(--accent));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.glass-effect {
    background: rgba(255, 255, 255, 0.05);
    -webkit-backdrop-filter: blur(10px);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.shadow-glow {
    box-shadow: 0 0 20px rgba(99, 102, 241, 0.3);
}

.no-select {
    user-select: none;
    -webkit-user-select: none;
}

/* ========== 20. 最终优化 ========== */

/* 优化渲染性能 */
* {
    box-sizing: border-box;
}

img,
svg {
    max-width: 100%;
    height: auto;
}

/* 防止布局偏移 */
.modal-content {
    content-visibility: auto;
}

/* .card-container 移除 content-visibility,可能导致布局问题 */


/* ========================================
   Modal Button Fixes
   ======================================== */

/* Ensure secondary buttons have proper styling */
.secondary-btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background: rgba(255, 255, 255, 0.05);
    color: #cbd5e1;
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
}

.secondary-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.2);
}

/* Cinema mode button fixes */
.cinema-controls .glass-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    white-space: nowrap;
}

.cinema-controls .glass-btn.circle {
    width: 55px;
    height: 55px;
    min-width: 55px;
    padding: 0;
}

/* Challenge modal button fixes */
.challenge-panel .secondary-btn {
    width: 100%;
    margin-top: 1rem;
}