html {
    --reasoning-bg: rgba(255, 255, 255, 0.3);
    --reasoning-border: rgba(0, 0, 0, 0.08);
    --reasoning-title-color: rgba(0, 0, 0, 0.7);
    --reasoning-title-done-color: rgba(0, 0, 0, 0.5);
    --reasoning-icon-opacity: 0.7;
    --reasoning-icon-done-opacity: 0.5;
    --reasoning-content-color: rgba(0, 0, 0, 0.5);
    --reasoning-scrollbar-thumb: rgba(0, 0, 0, 0.5);
    --reasoning-scrollbar-shadow: 0 0 0 0.5px rgba(255, 255, 255, 0.1),
        0 0 0 0.5px rgba(255, 255, 255, 0.1),
        0 0 0 0.5px inset rgba(0, 0, 0, 0.05),
        0 0 0 0.5px rgba(0, 0, 0, 0.05);
    --reasoning-title-shimmer: rgba(0, 0, 0, 0.15);
    --reasoning-header-expanded-bg: rgba(248, 248, 248, 0.95);
    --reasoning-chevron-hover-bg: rgba(0, 0, 0, 0.1);
    --reasoning-chevron-active-bg: rgba(0, 0, 0, 0.2);
}

html.dark {
    --reasoning-bg: rgba(0, 0, 0, 0.15);
    --reasoning-border: rgba(255, 255, 255, 0.1);
    --reasoning-title-color: rgba(255, 255, 255, 0.5);
    --reasoning-title-done-color: rgba(255, 255, 255, 0.5);
    --reasoning-icon-opacity: 1;
    --reasoning-icon-done-opacity: 1;
    --reasoning-icon-color: rgba(151, 151, 151, 1);
    --reasoning-content-color: rgba(255, 255, 255, 0.5);
    --reasoning-scrollbar-thumb: rgba(255, 255, 255, 0.3);
    --reasoning-scrollbar-shadow: 0 0 0 0.5px rgba(0, 0, 0, 0.1),
        0 0 0 0.5px rgba(0, 0, 0, 0.1),
        0 0 0 0.5px inset rgba(255, 255, 255, 0.05),
        0 0 0 0.5px rgba(255, 255, 255, 0.05);
    --reasoning-title-shimmer: rgba(255, 255, 255, 0.15);
    --reasoning-header-expanded-bg: rgba(24, 24, 24, 0.95);
    --reasoning-chevron-hover-bg: rgba(255, 255, 255, 0.1);
    --reasoning-chevron-active-bg: rgba(255, 255, 255, 0.05);
}

/* Reasoning - 深度思考块 */

.reasoning-block {
    margin: 4px 0 8px;
    border-radius: 10px;
    border: 1px solid var(--reasoning-border);
    background: var(--reasoning-bg);
    overflow: hidden;
    width: 100%;
}

.reasoning-block--compact {
    width: fit-content;
}

.reasoning-block--done .reasoning-block__title {
    color: var(--reasoning-title-done-color);
}

.reasoning-block__icon-wrapper,
.reasoning-block__chevron {
    opacity: var(--reasoning-icon-opacity);
}

.reasoning-block--done .reasoning-block__icon-wrapper,
.reasoning-block--done .reasoning-block__chevron {
    opacity: var(--reasoning-icon-done-opacity);
}

html.dark .reasoning-block__icon-wrapper,
html.dark .reasoning-block__chevron {
    color: var(--reasoning-icon-color);
}

/* ===== 标题栏 ===== */
.reasoning-block__header {
    display: flex;
    align-items: center;
    padding: 8px 12px;
    cursor: pointer;
    user-select: none;
    gap: 0;
    background: transparent;
}

/* deepthink 图标容器 */
.reasoning-block__icon-wrapper {
    position: relative;
    flex-shrink: 0;
    width: 24px;
    height: 24px;
    margin-right: 4px;
}

/* 动画 WebP 图标（思考中）和静态 SVG（完成）：绝对定位居中 */
.reasoning-block__icon-anim,
.reasoning-block__icon {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    transition: opacity 300ms ease;
}

.reasoning-block__icon-anim {
    width: 100%;
    height: 100%;
    object-fit: contain;
    opacity: 1;
}

.reasoning-block__icon {
    opacity: 0;
}

/* 思考完成：动图淡出，静态图淡入 */
.reasoning-block--done .reasoning-block__icon-anim {
    opacity: 0;
}

.reasoning-block--done .reasoning-block__icon {
    opacity: var(--reasoning-icon-done-opacity);
}

/* 标题文字 */
.reasoning-block__title {
    flex: 1;
    font-family: SourceHanSansSC-Normal, sans-serif;
    font-size: var(--uosai-font-size-base);
    font-weight: 400;
    font-style: normal;
    color: var(--reasoning-title-color);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* 折叠/展开按钮 */
.reasoning-block__chevron {
    flex-shrink: 0;
    margin-left: 14px;
}

.reasoning-block__chevron:hover {
    background: var(--reasoning-chevron-hover-bg);
}

.reasoning-block__chevron:active {
    background: var(--reasoning-chevron-active-bg);
}

/* ===== 内容区 ===== */

/* 思考中：高度随内容增长，最高 192px，内容向上滚动 */
.reasoning-block__body--thinking {
    max-height: 152px;
    overflow-y: auto;
    overflow-x: hidden;
    overscroll-behavior: contain;
    background: transparent;
    margin-right: 3px;
}

.reasoning-block__body--thinking::-webkit-scrollbar {
    width: 4px;
}

.reasoning-block__body--thinking::-webkit-scrollbar-thumb {
    height: 71px;
    border-radius: 4px;
    background-color: var(--reasoning-scrollbar-thumb);
    box-shadow: var(--reasoning-scrollbar-shadow);
}

.reasoning-block__body--thinking::-webkit-scrollbar-track {
    background: transparent;
}

/* 全部展开：向下无限展开；自带完整底半圈边框（方案A：边框下放给 header + body） */
.reasoning-block__body--full {
    overflow-y: visible;
    overflow-x: hidden;
    background: transparent;
    border: 1px solid var(--reasoning-border);
    border-top: none;
    border-radius: 0 0 10px 10px;
}

/* 展开状态：移除 block 自身边框与 overflow:hidden，让 sticky 生效；
   边框由 header（顶半圈）与 body--full（底半圈）各自承担 */
.reasoning-block--expanded {
    overflow: visible;
    border: none;
    position: relative;
}

/* 展开状态标题栏：吸附在滚动容器可视区顶部，直到整个块滚出视野 */
.reasoning-block--expanded .reasoning-block__header {
    position: sticky;
    top: 0;
    z-index: 2;
    border: 1px solid var(--reasoning-border);
    border-bottom: none;
    border-radius: 10px 10px 0 0;
    background: var(--reasoning-header-expanded-bg);
    backdrop-filter: blur(8px);
}

/* sticky 释放瞬间（block 下边追上 header 底部，header 即将随 block 整体上移）
   给 header 补一条带圆角的下框线，让"只剩 header 一条"的瞬间呈完整胶囊封口 */
.reasoning-block--expanded.reasoning-block--released .reasoning-block__header {
    border-bottom: 1px solid var(--reasoning-border);
    border-bottom-left-radius: 10px;
    border-bottom-right-radius: 10px;
}

/* 用伪元素填补 header 两个顶部圆角的 cutout 区域，
   挡住 body 的左右竖线在滚动超出时从圆角外透出。
   radial-gradient 以圆角中心为原点，半径外实心（涂掉竖线），半径内透明（保留圆角弧线）。
   仅在 --stuck 时启用，避免未吸附时覆盖透明切角；-1px 偏移抵消 header 的 1px 边框
   （absolute 定位参照 padding-box，向外扩 1px 才能对齐 border-box 角 & border-radius 弧心）。 */
.reasoning-block--expanded.reasoning-block--stuck .reasoning-block__header::before,
.reasoning-block--expanded.reasoning-block--stuck .reasoning-block__header::after {
    content: "";
    position: absolute;
    top: -1px;
    width: 10px;
    height: 10px;
    pointer-events: none;
}

.reasoning-block--expanded.reasoning-block--stuck .reasoning-block__header::before {
    left: -1px;
    background: radial-gradient(circle at 100% 100%,
            transparent 10px,
            var(--reasoning-header-expanded-bg) 10px);
}

.reasoning-block--expanded.reasoning-block--stuck .reasoning-block__header::after {
    right: -1px;
    background: radial-gradient(circle at 0% 100%,
            transparent 10px,
            var(--reasoning-header-expanded-bg) 10px);
}

/* ===== 思考中动画 ===== */

/* 图标动画由 animated WebP 实现（圆点脉冲 + 旋转），文字流光保留 CSS */

/* 文字流光：0%-40% 流动 */
@keyframes reasoning-shimmer {
    0%   { background-position: 100% 0; }
    40%  { background-position: 0% 0; }
    100% { background-position: 0% 0; }
}

.reasoning-block:not(.reasoning-block--done) .reasoning-block__title {
    flex: none;
    width: fit-content;
    background: linear-gradient(
        90deg,
        var(--reasoning-title-color) 0%,
        var(--reasoning-title-color) 40%,
        var(--reasoning-title-shimmer) 47%,
        var(--reasoning-title-shimmer) 53%,
        var(--reasoning-title-color) 60%,
        var(--reasoning-title-color) 100%
    );
    background-size: 300% 100%;
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: reasoning-shimmer 2.5s linear infinite;
}


/* 标题收缩后，chevron 靠 auto margin 右对齐 */
.reasoning-block:not(.reasoning-block--done) .reasoning-block__chevron {
    margin-left: auto;
}

/* 思考文本 */
.reasoning-block__content {
    padding: 0 20px 10px;
    font-family: SourceHanSansSC-Normal, sans-serif;
    font-size: var(--uosai-font-size-sm);
    line-height: var(--uosai-line-height-extra-relaxed);
    font-weight: 400;
    font-style: normal;
    color: var(--reasoning-content-color);
    white-space: pre-wrap;
    word-break: break-word;
}
