/* ==========================================================================
   现代加载动效样式
   ========================================================================== */

/* 基础加载器变量 */
:root {
    --loader-primary: #4285f4;
    --loader-secondary: #667eea;
    --loader-accent: #764ba2;
    --loader-size-sm: 16px;
    --loader-size-md: 24px;
    --loader-size-lg: 32px;
    --loader-size-xl: 48px;
}

/* ==========================================================================
   旋转类加载器
   ========================================================================== */

/* 经典旋转加载器 - 改进版 */
.loader-spin {
    display: inline-block;
    width: var(--loader-size-md);
    height: var(--loader-size-md);
    border: 3px solid rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    border-top: 3px solid var(--loader-primary);
    animation: spin 0.8s cubic-bezier(0.68, -0.55, 0.265, 1.55) infinite;
}

/* 渐变旋转加载器 */
.loader-gradient-spin {
    display: inline-block;
    width: var(--loader-size-md);
    height: var(--loader-size-md);
    border-radius: 50%;
    border: 3px solid transparent;
    border-top: 3px solid var(--loader-primary);
    border-right: 3px solid var(--loader-secondary);
    animation: spin 1s linear infinite;
    position: relative;
}

/* 双环旋转加载器 */
.loader-double-ring {
    display: inline-block;
    width: var(--loader-size-md);
    height: var(--loader-size-md);
    position: relative;
}

.loader-double-ring::before,
.loader-double-ring::after {
    content: '';
    position: absolute;
    border-radius: 50%;
    border: 2px solid transparent;
    border-top: 2px solid var(--loader-primary);
    animation: spin 1s linear infinite;
}

.loader-double-ring::before {
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
}

.loader-double-ring::after {
    width: 70%;
    height: 70%;
    top: 15%;
    left: 15%;
    border-top-color: var(--loader-secondary);
    animation-direction: reverse;
    animation-duration: 0.7s;
}

/* ==========================================================================
   脉冲类加载器
   ========================================================================== */

/* 脉冲圆点 */
.loader-pulse {
    display: inline-block;
    width: var(--loader-size-md);
    height: var(--loader-size-md);
    background: var(--loader-primary);
    border-radius: 50%;
    animation: pulse-scale 1.5s ease-in-out infinite;
}

/* 三点脉冲 */
.loader-dots {
    display: inline-flex;
    gap: 4px;
    align-items: center;
}

.loader-dots::before,
.loader-dots::after,
.loader-dots {
    content: '';
    width: 8px;
    height: 8px;
    background: var(--loader-primary);
    border-radius: 50%;
    animation: pulse-opacity 1.4s ease-in-out infinite;
}

.loader-dots::before {
    animation-delay: -0.32s;
}

.loader-dots::after {
    animation-delay: 0.32s;
}

/* 波浪脉冲 */
.loader-wave {
    display: inline-flex;
    gap: 2px;
    align-items: flex-end;
    height: var(--loader-size-md);
}

.loader-wave span {
    display: block;
    width: 3px;
    height: 100%;
    background: var(--loader-primary);
    border-radius: 2px;
    animation: wave-scale 1.2s ease-in-out infinite;
}

.loader-wave span:nth-child(2) { animation-delay: 0.1s; }
.loader-wave span:nth-child(3) { animation-delay: 0.2s; }
.loader-wave span:nth-child(4) { animation-delay: 0.3s; }
.loader-wave span:nth-child(5) { animation-delay: 0.4s; }

/* ==========================================================================
   进度条类加载器
   ========================================================================== */

/* 渐变进度条 */
.loader-progress {
    width: 200px;
    height: 4px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 2px;
    overflow: hidden;
    position: relative;
}

.loader-progress::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, var(--loader-primary), var(--loader-secondary), transparent);
    animation: progress-slide 2s ease-in-out infinite;
}

/* 脉冲进度条 */
.loader-progress-pulse {
    width: 200px;
    height: 4px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 2px;
    overflow: hidden;
    position: relative;
}

.loader-progress-pulse::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, var(--loader-primary), var(--loader-secondary));
    border-radius: 2px;
    animation: progress-pulse 2s ease-in-out infinite;
}

/* ==========================================================================
   特效类加载器
   ========================================================================== */

/* 粒子效果 */
.loader-particles {
    display: inline-block;
    width: var(--loader-size-lg);
    height: var(--loader-size-lg);
    position: relative;
}

.loader-particles::before,
.loader-particles::after {
    content: '';
    position: absolute;
    width: 8px;
    height: 8px;
    background: var(--loader-primary);
    border-radius: 50%;
    animation: particles-orbit 2s linear infinite;
}

.loader-particles::before {
    top: 0;
    left: 50%;
    transform: translateX(-50%);
}

.loader-particles::after {
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    animation-delay: 1s;
    background: var(--loader-secondary);
}

/* 呼吸效果 */
.loader-breathe {
    display: inline-block;
    width: var(--loader-size-md);
    height: var(--loader-size-md);
    background: radial-gradient(circle, var(--loader-primary), var(--loader-secondary));
    border-radius: 50%;
    animation: breathe 2s ease-in-out infinite;
}

/* 液体效果 */
.loader-liquid {
    display: inline-block;
    width: var(--loader-size-lg);
    height: var(--loader-size-lg);
    border-radius: 50%;
    background: linear-gradient(45deg, var(--loader-primary), var(--loader-secondary));
    position: relative;
    overflow: hidden;
}

.loader-liquid::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 120%;
    height: 120%;
    background: radial-gradient(circle, rgba(255,255,255,0.3), transparent 70%);
    border-radius: 50%;
    animation: liquid-wave 3s ease-in-out infinite;
    transform: translate(-50%, -50%);
}

/* ==========================================================================
   组合加载器
   ========================================================================== */

/* 加载容器 */
.loading-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 16px;
    padding: 40px 20px;
    text-align: center;
}

.loading-text {
    color: #ccc;
    font-size: 14px;
    font-weight: 500;
    margin: 0;
}

.loading-subtitle {
    color: #888;
    font-size: 12px;
    margin: 0;
    animation: pulse-opacity 2s ease-in-out infinite;
}

/* 卡片加载状态 */
.card-loading {
    background: #1a1a1a;
    border: 1px solid #333;
    border-radius: 12px;
    padding: 24px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.card-loading::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.05), transparent);
    animation: shimmer 2s ease-in-out infinite;
}

/* ==========================================================================
   尺寸变体
   ========================================================================== */

/* 小尺寸 */
.loader-sm {
    width: var(--loader-size-sm) !important;
    height: var(--loader-size-sm) !important;
}

.loader-sm::before,
.loader-sm::after {
    border-width: 2px;
}

/* 大尺寸 */
.loader-lg {
    width: var(--loader-size-lg) !important;
    height: var(--loader-size-lg) !important;
}

.loader-lg::before,
.loader-lg::after {
    border-width: 4px;
}

/* 超大尺寸 */
.loader-xl {
    width: var(--loader-size-xl) !important;
    height: var(--loader-size-xl) !important;
}

.loader-xl::before,
.loader-xl::after {
    border-width: 5px;
}

/* ==========================================================================
   动画定义
   ========================================================================== */

@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

@keyframes pulse-scale {
    0%, 100% { transform: scale(1); opacity: 1; }
    50% { transform: scale(1.2); opacity: 0.7; }
}

@keyframes pulse-opacity {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.3; }
}

@keyframes wave-scale {
    0%, 100% { transform: scaleY(0.3); }
    50% { transform: scaleY(1); }
}

@keyframes progress-slide {
    0% { left: -100%; }
    100% { left: 100%; }
}

@keyframes progress-pulse {
    0%, 100% { opacity: 1; transform: scaleX(1); }
    50% { opacity: 0.7; transform: scaleX(0.8); }
}

@keyframes particles-orbit {
    0% { transform: translateX(-50%) rotate(0deg) translateY(-16px) rotate(0deg); }
    100% { transform: translateX(-50%) rotate(360deg) translateY(-16px) rotate(-360deg); }
}

@keyframes breathe {
    0%, 100% { transform: scale(1); opacity: 1; }
    50% { transform: scale(1.1); opacity: 0.8; }
}

@keyframes liquid-wave {
    0%, 100% { transform: translate(-50%, -50%) rotate(0deg); }
    50% { transform: translate(-50%, -50%) rotate(180deg); }
}

@keyframes shimmer {
    0% { left: -100%; }
    100% { left: 100%; }
}

/* ==========================================================================
   响应式适配
   ========================================================================== */

@media (max-width: 768px) {
    .loading-container {
        padding: 30px 15px;
        gap: 12px;
    }
    
    .loading-text {
        font-size: 13px;
    }
    
    .loading-subtitle {
        font-size: 11px;
    }
    
    .loader-progress,
    .loader-progress-pulse {
        width: 150px;
    }
}

@media (max-width: 480px) {
    .loading-container {
        padding: 20px 10px;
        gap: 10px;
    }
    
    .loader-progress,
    .loader-progress-pulse {
        width: 120px;
    }
}

/* ==========================================================================
   深色主题优化
   ========================================================================== */

@media (prefers-color-scheme: dark) {
    :root {
        --loader-primary: #5a9cfc;
        --loader-secondary: #7c3aed;
        --loader-accent: #8b5cf6;
    }
}

/* ==========================================================================
   减少动画偏好
   ========================================================================== */

@media (prefers-reduced-motion: reduce) {
    .loader-spin,
    .loader-gradient-spin,
    .loader-double-ring,
    .loader-pulse,
    .loader-dots,
    .loader-wave,
    .loader-progress,
    .loader-progress-pulse,
    .loader-particles,
    .loader-breathe,
    .loader-liquid,
    .card-loading {
        animation: none;
    }
    
    .loader-pulse {
        opacity: 0.7;
    }
}