.plank-test-page {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: #000000;
    display: none;
    flex-direction: column;
    min-height: 100vh;
    z-index: 10;
}

.plank-test-page.active { 
    display: flex; 
}

.plank-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 1.5rem 1rem;
    z-index: 10;
    flex-shrink: 0;
}
.plank-header-left { display: flex; gap: 0.75rem; align-items: center; }
.plank-btn {
    background: #151515;
    border: 3px solid #5d2500;
    border-radius: 1rem;
    color: #FF6600;
    padding: 2rem 3rem;
    font-size: 2rem;
    cursor: pointer;
    font-family: 'HarmonyOS_Sans_SC_Regular', Arial, sans-serif;
    min-width: 15rem;
    min-height: 5rem;
}
.plank-header-right { display: flex; gap: 0.75rem; align-items: center; }
.plank-small-btn {
    background: #151515;
    border: 3px solid #5d2500;
    border-radius: 1rem;
    color: #FF6600;
    min-height: 5rem;
    min-width: 5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    cursor: pointer;
    font-family: 'HarmonyOS_Sans_SC_Regular', Arial, sans-serif;
    padding: 2rem 3rem;
}
.plank-test-content { display: flex; flex-direction: column; align-items: center; padding: 2rem 1.5rem; }
.plank-timer-header { display: flex; justify-content: space-between; align-items: center; width: 100%; padding: 0 6rem;}
.plank-test-timer-underline { width: 55rem; height: 2px; background-color: #272727; position: relative; }
.plank-timer-label { color: #ffffff; font-size: 1.8rem; font-family: 'HarmonyOS_Sans_SC_Regular', Arial, sans-serif; margin-bottom: 1rem;}
#plankImageDiv {
    position: relative;
    width: 100%;
    height: 26rem; /* 放大整体高度 */
    display: flex;
    justify-content: center;
    align-items: flex-start;
    margin-top: 8rem;
}
.plank-bg-center, .plank-fill-layer {
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60rem;
    height: 30rem;
}

.plank-fill-layer {
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    height: 100%;
    background: linear-gradient(to top, #763104, #ff6600);
    transition: height 0.25s ease;
}
.plank-text-overlay {
    position: absolute;
    left: 0; right: 0; top: 0; bottom: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    pointer-events: none;
}
.plank-count-number { color: #ffffff; font-size:20rem; font-family: 'Morganite-Black-2', Arial, sans-serif; line-height: 1; margin-top: 6rem; }
.plank-count-label { color: #ffffff; font-size: 4rem; font-family: 'HarmonyOS_Sans_SC_Regular', Arial, sans-serif; margin-top: 0.4rem; }

/* 重心显示区域样式 */
.center-of-gravity-container {
    display: flex;
    justify-content: center;
    gap: 0;
    margin-top: 10rem;
    width: 100%;
    height: 3rem;
}

.center-of-gravity-left,
.center-of-gravity-right {
    flex: 1;
    max-width: 16rem;
    height: 3rem;
    background-color: #272727;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #000000;
    font-size: 2rem;
    font-family: 'HarmonyOS_Sans_SC_Bold', Arial, sans-serif;
    cursor: pointer;
    transition: background-color 0.3s ease;
    margin: 0.2rem;
}

.center-of-gravity-left {
    border-radius: 1.5rem 0 0 1.5rem; /* 左侧圆角 */
}

.center-of-gravity-right {
    border-radius: 0 1.5rem 1.5rem 0; /* 右侧圆角 */
}

.center-of-gravity-left.active,
.center-of-gravity-right.active {
    background-color: #FF6600;
}

/* 身体示意图 */
.plank-body-visual {
    position: relative;
    width: 40rem;
    height: 16rem;
    margin: 4rem auto 0;
    padding: 2rem 3rem;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #151515;
    border-radius: 1rem;
}

.plank-body-segment {
    position: absolute;
    top: 50%;
    left: 70%;
    width: 100%;
    height: 100%;
    transform: translate(-50%, -50%);
    display: flex;
    align-items: center;
    justify-content: center;
    pointer-events: none;
}

.plank-body-head {
    z-index: 2;
}

.plank-body-leg {
    z-index: 1;
}

.plank-body-segment img {
    display: block;
    width: 18rem;
    height: auto;
    transform-origin:6%;
    transform: rotate(-90deg);
    transition: transform 0.3s ease;
}

.plank-body-leg img {
    transform: scaleX(-1) rotate(-90deg);
}

/* 左右两侧旋转80°的虚线（初始为垂直，然后分别向左向右旋转80°） */
.plank-dashed-line {
    position: absolute;
    top: 88%;
    left: 50%;
    width: 2px;
    height: 12rem;
    transform-origin: 50% 0;
    pointer-events: none;
    z-index: 0;
}

.plank-dashed-line::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border-left: 2px dashed #FF6600;
    opacity: 0.6;
}

.plank-dashed-line-left {
    transform: translate(-50%, -50%) rotate(100deg);
    margin-left: -1rem;
}

.plank-dashed-line-right {
    transform: translate(-50%, -50%) rotate(275deg);
    margin-left: 1rem;
}

.plank-body-labels {
    width: 40rem;
    margin: 1.5rem auto 0;
    display: flex;
    justify-content: space-between;
    color: #ffffff;
    font-family: 'HarmonyOS_Sans_SC_Regular', Arial, sans-serif;
    font-size: 1.6rem;
    text-transform: capitalize;
    letter-spacing: 0.1rem;
}

.plank-angle-display {
    width: 40rem;
    margin: 1.5rem auto 0;
    display: flex;
    justify-content: space-between;
    gap: 2rem;
}

.plank-angle-item {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.plank-angle-label {
    color: #ffffff;
    font-family: 'HarmonyOS_Sans_SC_Regular', Arial, sans-serif;
    font-size: 1.4rem;
    opacity: 0.8;
}

.plank-angle-value {
    color: #FF6600;
    font-family: 'HarmonyOS_Sans_SC_Bold', Arial, sans-serif;
    font-size: 2rem;
}

.plank-height-display {
    width: 40rem;
    margin: 1.5rem auto 0;
    display: flex;
    justify-content: space-between;
    gap: 2rem;
}

.plank-height-item {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.plank-height-label {
    color: #ffffff;
    font-family: 'HarmonyOS_Sans_SC_Regular', Arial, sans-serif;
    font-size: 1.4rem;
    opacity: 0.8;
}

.plank-height-value {
    color: #FF6600;
    font-family: 'HarmonyOS_Sans_SC_Bold', Arial, sans-serif;
    font-size: 2rem;
}