:root {
    --primary-color: #2A2F4D;
    --secondary-color: #4FD1C5;
    --accent-color: #667EEA;

    --bs-blue: #0d6efd;
    --bs-indigo: #6610f2;
    --bs-purple: #6f42c1;
    --bs-pink: #d63384;
    --bs-red: #dc3545;
    --bs-orange: #fd7e14;
    --bs-yellow: #ffc107;
    --bs-green: #198754;
    --bs-teal: #20c997;
    --bs-cyan: #0dcaf0;
    --bs-white: #fff;
    --bs-gray: #6c757d;
    --bs-gray-dark: #343a40;
    --bs-gray-100: #f8f9fa;
    --bs-gray-200: #e9ecef;
    --bs-gray-300: #dee2e6;
    --bs-gray-400: #ced4da;
    --bs-gray-500: #adb5bd;
    --bs-gray-600: #6c757d;
    --bs-gray-700: #495057;
    --bs-gray-800: #343a40;
    --bs-gray-900: #212529;
    --bs-primary: #0d6efd;
    --bs-secondary: #6c757d;
    --bs-success: #198754;
    --bs-info: #0dcaf0;
    --bs-warning: #ffc107;
    --bs-danger: #dc3545;
    --bs-light: #f8f9fa;
    --bs-dark: #212529;
    --bs-primary-rgb: 13,110,253;
    --bs-secondary-rgb: 108,117,125;
    --bs-success-rgb: 25,135,84;
    --bs-info-rgb: 13,202,240;
    --bs-warning-rgb: 255,193,7;
    --bs-danger-rgb: 220,53,69;
    --bs-light-rgb: 248,249,250;
    --bs-dark-rgb: 33,37,41;
    --bs-white-rgb: 255,255,255;
    --bs-black-rgb: 0,0,0;
    --bs-body-color-rgb: 33,37,41;
    --bs-body-bg-rgb: 255,255,255;
    --bs-font-sans-serif: system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,"Noto Sans","Liberation Sans",sans-serif,"Apple Color Emoji","Segoe UI Emoji","Segoe UI Symbol","Noto Color Emoji";
    --bs-font-monospace: SFMono-Regular,Menlo,Monaco,Consolas,"Liberation Mono","Courier New",monospace;
    --bs-gradient: linear-gradient(180deg, rgba(255, 255, 255, 0.15), rgba(255, 255, 255, 0));
    --bs-body-font-family: var(--bs-font-sans-serif);
    --bs-body-font-size: 1rem;
    --bs-body-font-weight: 400;
    --bs-body-line-height: 1.5;
    --bs-body-color: #212529;
    --bs-body-bg: #fff
}

body {
    font-family: 'Helvetica Neue', system-ui, sans-serif;
    line-height: 1.6;
}

@media (min-width: 768px) {
    .container {
        width: 100%;
    }
}
@media (min-width:1200px){.container{width:100%;max-width: 1920px;}}

/* 视差滚动效果 */
.course-overview::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 120%;
    background: linear-gradient(45deg, #2A2F4D 0%, #4A5568 100%);
    transform: translateZ(10px);
    z-index: -1;
}

/* 课程概览3D效果 */
.course-overview .row {
    transform-style: preserve-3d;
    transform: translateZ(20px);
    transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}



/* 学习路径页面专属样式 */
.course-overview img {
    border: 3px solid var(--bs-primary);
    box-shadow: 0 0.5rem 1rem rgba(0, 123, 255, 0.15);
}

.timeline-item:nth-child(2) { animation-delay: 0.3s; }


.timeline-item:nth-child(3) { animation-delay: 0.6s; }


.timeline-item:nth-child(4) { animation-delay: 0.9s; }

.video-card {
    border-radius: 8px;
    overflow: hidden;
    transform-style: preserve-3d;
    transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    perspective: 1200px;
}



.video-card:hover {
    transform: scale(1.05) rotateZ(2deg);
    box-shadow: 0 10px 30px rgba(79, 209, 197, 0.3);
}



.video-card::before {
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    background: linear-gradient(45deg, rgba(255,255,255,0.1), transparent);
    backface-visibility: hidden;
}

.resources-download .list-group-item {
    transition: all 0.3s ease;
    border-left: 3px solid transparent;
}



.resources-download .list-group-item:hover {
    border-left-color: var(--bs-primary);
    padding-left: 1.5rem;
}



.resources-download .list-group-item::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    height: 2px;
    width: 0%;
    background: var(--bs-primary);
    transition: width 1s ease;
}

.resources-download .list-group-item:hover::after {
    width: 80%;
}

@keyframes progressPulse {
    0% { opacity: 0.8; }
    50% { opacity: 0.4; }
    100% { opacity: 0.8; }
}

.progress-indicator {
    position: relative;
    height: 4px;
    background: rgba(0,123,255,0.1);
    overflow: hidden;
}

.progress-indicator::before {
    content: '';
    position: absolute;
    width: 60%;
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    animation: progressPulse 1.5s infinite ease-in-out;
}





/* 导航栏美化 */
.ai-navbar {
    background: linear-gradient(135deg, #2A2F4D, #667EEA);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}


.nav-link {
    position: relative;
    padding: 0.5rem 1rem !important;
    transition: all 0.3s;
}

@keyframes slideInDown {
    from {
        transform: translateY(-100%);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

@keyframes slideOutUp {
    from {
        transform: translateY(0);
        opacity: 1;
    }
    to {
        transform: translateY(-100%);
        opacity: 0;
    }
}

.news-card {
    transition: transform 0.3s ease;
    /* 关键属性：固定背景图高度，宽度按比例自适应 */
    background-size: 100% auto!important;
    /* 背景居中显示（可选） */
    background-position: center;
    /* 防止背景重复 */
    background-repeat: no-repeat;
}

.news-card.slide-in {
    animation: slideInDown 0.3s ease-out;
}

.news-card.slide-out {
    animation: slideOutUp 0.3s ease-out;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: white;
    transition: width 0.3s;
}

.video-card {
    border-radius: 8px;
    overflow: hidden;
    transform-style: preserve-3d;
    transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    perspective: 1200px;
}

.video-card:hover {
    transform: translateZ(30px) rotateX(5deg) rotateY(-5deg);
    box-shadow: 0 20px 40px rgba(79, 209, 197, 0.3);
}

.video-card::before {
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    background: linear-gradient(45deg, rgba(255,255,255,0.1), transparent);
    backface-visibility: hidden;
}

.nav-link:hover::after {
    width: 70%;
}

.resources-download .list-group-item {
    transition: all 0.3s ease;
    border-left: 3px solid transparent;
}

.resources-download .list-group-item:hover {
    border-left-color: var(--bs-primary);
    padding-left: 1.5rem;
}

.resources-download .list-group-item::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    height: 2px;
    width: 0%;
    background: var(--bs-primary);
    transition: width 1s ease;
}

.resources-download .list-group-item:hover::after {
    width: 80%;
}

@keyframes progressPulse {
    0% { opacity: 0.8; }
    50% { opacity: 0.4; }
    100% { opacity: 0.8; }
}

.progress-indicator {
    position: relative;
    height: 4px;
    background: rgba(0,123,255,0.1);
    overflow: hidden;
}

.progress-indicator::before {
    content: '';
    position: absolute;
    width: 60%;
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    animation: progressPulse 1.5s infinite ease-in-out;
}


/* Banner区美化 */
.main-banner {
    background: linear-gradient(rgb(213 103 21), rgb(49 157 98)), url(https://dify360.com/uploads/20250317/36a40a8….jpg) center / cover no-repeat;
    display: flex;
    align-items: center;
    padding: 0px 0px;
    margin-bottom: 20px;
    /* clip-path: polygon(0 0, 100% 0, 100% 90%, 0% 100%); */
}

.banner-title {
    font-size: 2.5rem;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

@media screen and (max-width: 768px) {
    .main-banner {
        padding-top: 30px;
        margin-bottom: 0px;
    }
    .banner-title{
        font-size: 1.5rem;
    }

}


/* 卡片动效 */
.feature-card {
    transition: transform 0.3s ease-out, box-shadow 0.3s linear;
    will-change: transform;
    border: none;
    border-radius: 15px;
    overflow: hidden;
    position: relative;
    z-index: 1;
    box-shadow: 0 2px 6px rgba(0,0,0,0.08);
}

/* 学习路径页面专属样式 */


.feature-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 12px rgba(0,0,0,0.08);
}

/* 特色标签 */
.hot-badge {
    position: absolute;
    top: -7px;
    right: -7px;
    background: var(--badge-bg);
    color: var(--badge-color);
    padding: 6px 12px;
    border-radius: 10px;
    font-size: 0.8rem;
}


/* 进度条美化 */
.progress {
    height: 8px;
    border-radius: 4px;
}

.h-150 {
    height: 150px;
}

.h-180 {
    height: 180px;
}

.h-200 {
    height: 200px;
}

.h-230 {
    height: 230px;
}

/*bootstrap相关*/
.bs-flex{
    display: flex;
}
.justify-content-start {
    justify-content: flex-start!important
}

.justify-content-end {
    justify-content: flex-end!important
}

.justify-content-center {
    justify-content: center!important
}

.justify-content-between {
    justify-content: space-between!important
}

.justify-content-around {
    justify-content: space-around!important
}

.justify-content-evenly {
    justify-content: space-evenly!important
}

.align-items-start {
    align-items: flex-start!important
}

.align-items-end {
    align-items: flex-end!important
}

.align-items-center {
    align-items: center!important
}

.align-items-baseline {
    align-items: baseline!important
}

.align-items-stretch {
    align-items: stretch!important
}

.align-content-start {
    align-content: flex-start!important
}

.align-content-end {
    align-content: flex-end!important
}

.align-content-center {
    align-content: center!important
}

.align-content-between {
    align-content: space-between!important
}

.align-content-around {
    align-content: space-around!important
}

.align-content-stretch {
    align-content: stretch!important
}

.align-self-auto {
    align-self: auto!important
}

.align-self-start {
    align-self: flex-start!important
}

.align-self-end {
    align-self: flex-end!important
}

.align-self-center {
    align-self: center!important
}

.align-self-baseline {
    align-self: baseline!important
}

.align-self-stretch {
    align-self: stretch!important
}


.bg-primary {
    --bs-bg-opacity: 1;
    background-color: rgba(var(--bs-primary-rgb),var(--bs-bg-opacity))!important
}

.bg-secondary {
    --bs-bg-opacity: 1;
    background-color: rgba(var(--bs-secondary-rgb),var(--bs-bg-opacity))!important
}

.bg-success {
    --bs-bg-opacity: 1;
    background-color: rgba(var(--bs-success-rgb),var(--bs-bg-opacity))!important
}

.bg-info {
    --bs-bg-opacity: 1;
    background-color: rgba(var(--bs-info-rgb),var(--bs-bg-opacity))!important
}

.bg-warning {
    --bs-bg-opacity: 1;
    background-color: rgba(var(--bs-warning-rgb),var(--bs-bg-opacity))!important
}

.bg-danger {
    --bs-bg-opacity: 1;
    background-color: rgba(var(--bs-danger-rgb),var(--bs-bg-opacity))!important
}

.bg-light {
    --bs-bg-opacity: 1;
    background-color: rgba(var(--bs-light-rgb),var(--bs-bg-opacity))!important
}

.bg-dark {
    --bs-bg-opacity: 1;
    background-color: rgba(var(--bs-dark-rgb),var(--bs-bg-opacity))!important
}

.bg-black {
    --bs-bg-opacity: 1;
    background-color: rgba(var(--bs-black-rgb),var(--bs-bg-opacity))!important
}

.bg-white {
    --bs-bg-opacity: 1;
    background-color: rgba(var(--bs-white-rgb),var(--bs-bg-opacity))!important
}

.bg-body {
    --bs-bg-opacity: 1;
    background-color: rgba(var(--bs-body-bg-rgb),var(--bs-bg-opacity))!important
}

.bg-transparent {
    --bs-bg-opacity: 1;
    background-color: transparent!important
}

.bg-opacity-10 {
    --bs-bg-opacity: 0.1
}

.bg-opacity-25 {
    --bs-bg-opacity: 0.25
}

.bg-opacity-50 {
    --bs-bg-opacity: 0.5
}

.bg-opacity-75 {
    --bs-bg-opacity: 0.75
}

.bg-opacity-100 {
    --bs-bg-opacity: 1
}

.bg-gradient {
    background-image: var(--bs-gradient)!important
}


.text-start {
    text-align: left!important
}

.text-end {
    text-align: right!important
}

.text-center {
    text-align: center!important
}

.text-decoration-none {
    text-decoration: none!important
}

.text-decoration-underline {
    text-decoration: underline!important
}

.text-decoration-line-through {
    text-decoration: line-through!important
}

.text-lowercase {
    text-transform: lowercase!important
}

.text-uppercase {
    text-transform: uppercase!important
}

.text-capitalize {
    text-transform: capitalize!important
}

.text-wrap {
    white-space: normal!important
}

.text-nowrap {
    white-space: nowrap!important
}

.text-break {
    word-wrap: break-word!important;
    word-break: break-word!important
}

.text-primary {
    --bs-text-opacity: 1;
    color: rgba(var(--bs-primary-rgb),var(--bs-text-opacity))!important
}

.text-secondary {
    --bs-text-opacity: 1;
    color: rgba(var(--bs-secondary-rgb),var(--bs-text-opacity))!important
}

.text-success {
    --bs-text-opacity: 1;
    color: rgba(var(--bs-success-rgb),var(--bs-text-opacity))!important
}

.text-info {
    --bs-text-opacity: 1;
    color: rgba(var(--bs-info-rgb),var(--bs-text-opacity))!important
}

.text-warning {
    --bs-text-opacity: 1;
    color: rgba(var(--bs-warning-rgb),var(--bs-text-opacity))!important
}

.text-danger {
    --bs-text-opacity: 1;
    color: rgba(var(--bs-danger-rgb),var(--bs-text-opacity))!important
}

.text-light {
    --bs-text-opacity: 1;
    color: rgba(var(--bs-light-rgb),var(--bs-text-opacity))!important
}

.text-dark {
    --bs-text-opacity: 1;
    color: rgba(var(--bs-dark-rgb),var(--bs-text-opacity))!important
}

.text-black {
    --bs-text-opacity: 1;
    color: rgba(var(--bs-black-rgb),var(--bs-text-opacity))!important
}

.text-white {
    --bs-text-opacity: 1;
    padding-bottom: 30px;
}

.text-body {
    --bs-text-opacity: 1;
    color: rgba(var(--bs-body-color-rgb),var(--bs-text-opacity))!important
}

.text-muted {
    --bs-text-opacity: 1;
    color: #6c757d!important
}

.text-black-50 {
    --bs-text-opacity: 1;
    color: rgba(0,0,0,.5)!important
}

.text-white-50 {
    --bs-text-opacity: 1;
    color: rgba(255,255,255,.5)!important
}

.text-reset {
    --bs-text-opacity: 1;
    color: inherit!important
}

.text-opacity-25 {
    --bs-text-opacity: 0.25
}

.text-opacity-50 {
    --bs-text-opacity: 0.5
}

.text-opacity-75 {
    --bs-text-opacity: 0.75
}

.text-opacity-100 {
    --bs-text-opacity: 1
}


.fs-1 {
    font-size: calc(1.375rem + 1.5vw)!important
}

.fs-2 {
    font-size: calc(1.325rem + .9vw)!important
}

.fs-3 {
    font-size: calc(1.3rem + .6vw)!important
}

.fs-4 {
    font-size: calc(1.275rem + .3vw)!important
}

.fs-5 {
    font-size: 1.25rem!important
}

.fs-6 {
    font-size: 1rem!important
}

.fst-italic {
    font-style: italic!important
}

.fst-normal {
    font-style: normal!important
}

.fw-light {
    font-weight: 300!important
}

.fw-lighter {
    font-weight: lighter!important
}

.fw-normal {
    font-weight: 400!important
}

.fw-bold {
    font-weight: 700!important
}

.fw-bolder {
    font-weight: bolder!important
}

.lh-1 {
    line-height: 1!important
}

.lh-sm {
    line-height: 1.25!important
}

.lh-base {
    line-height: 1.5!important
}

.lh-lg {
    line-height: 2!important
}