/* 真境挑战页 - 各主题独立样式 */

/* ========== 身份入口卡片（问题解决者 / 企业 / 导师） ========== */
.identity-cards-section {
    padding: 48px 0 56px;
    background: #e8e8e8;
}

.identity-cards-wrap {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    box-sizing: border-box;
}

.identity-card {
    background: #fff;
    border-radius: 8px;
    padding: 0;
    box-shadow: 0 1px 3px rgba(0,0,0,0.08);
    border: 1px solid #ddd;
    border-top: 4px solid var(--identity-accent);
    display: flex;
    flex-direction: column;
    text-align: left;
    transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.identity-card:hover {
    box-shadow: 0 6px 20px rgba(0,0,0,0.12);
    transform: translateY(-2px);
}

.identity-card-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    padding: 24px 24px 0;
}

.identity-card-title {
    font-size: 22px;
    font-weight: 700;
    color: #333;
    margin: 0;
}

.identity-card-icon {
    color: #555;
    flex-shrink: 0;
}

.identity-card-solvers .identity-card-icon { color: #0d9488; }
.identity-card-companies .identity-card-icon { color: #16a34a; }
.identity-card-mentors .identity-card-icon { color: #dc2626; }

.identity-card-cta {
    font-size: 16px;
    font-weight: 600;
    color: var(--identity-accent);
    margin: 12px 24px 16px;
    padding: 0;
}

.identity-card-list {
    list-style: none;
    margin: 0 24px 20px;
    padding: 0;
    flex: 1;
}

.identity-card-list li {
    position: relative;
    padding: 6px 0 6px 18px;
    font-size: 14px;
    color: #444;
    line-height: 1.5;
}

.identity-card-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 12px;
    width: 5px;
    height: 5px;
    border-radius: 50%;
    background: #888;
}

.identity-card-link {
    display: inline-block;
    font-size: 14px;
    font-weight: 600;
    color: #444;
    text-decoration: none;
    padding: 16px 24px 24px;
    transition: color 0.2s;
}

.identity-card-link:hover {
    color: #111;
}

.identity-card-arrow {
    color: var(--identity-accent);
    margin-left: 2px;
}

.identity-card-solvers {
    --identity-accent: #0d9488;
}

.identity-card-companies {
    --identity-accent: #16a34a;
}

.identity-card-mentors {
    --identity-accent: #dc2626;
}

@media (max-width: 900px) {
    .identity-cards-wrap {
        grid-template-columns: 1fr;
    }
}

/* ========== 页面级 ========== */
.challenge-sections .container.container-wide {
    max-width: 1100px;
    width: 100%;
    margin: 0 auto;
    padding: 0 24px;
    box-sizing: border-box;
}

.challenge-sections {
    padding: 32px 0 72px;
}

/* 锚点导航 */
.challenge-nav-anchors {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 12px 20px;
    margin-bottom: 48px;
    padding: 16px 20px;
    background: var(--light-gray);
    border-radius: 16px;
    box-shadow: inset 0 1px 0 rgba(255,255,255,0.8);
}

.challenge-nav-anchors a {
    color: var(--deep-space-blue);
    text-decoration: none;
    font-weight: 600;
    font-size: 14px;
    padding: 8px 16px;
    border-radius: 999px;
    transition: background 0.2s, color 0.2s;
}

.challenge-nav-anchors a:hover {
    background: var(--deep-space-blue);
    color: white;
}

.challenge-nav-anchors a:focus-visible {
    outline: 2px solid var(--starlight-gold);
    outline-offset: 2px;
}

/* 主题区块通用 */
.challenge-theme {
    margin-bottom: 56px;
    padding: 32px 28px 36px;
    border-radius: 20px;
    scroll-margin-top: 120px;
}

.challenge-theme:last-child {
    margin-bottom: 0;
}

.challenge-theme-header {
    margin-bottom: 24px;
}

.challenge-theme-label {
    display: inline-block;
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    margin-bottom: 8px;
}

.challenge-theme h2 {
    font-size: 24px;
    margin-bottom: 12px;
    font-weight: 700;
}

.challenge-theme-lead {
    font-size: 15px;
    line-height: 1.7;
    color: var(--dark-gray);
    max-width: 720px;
}

.challenge-theme-body {
    margin-top: 20px;
}

.challenge-theme-highlights {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 20px;
}

.highlight-tag {
    display: inline-block;
    padding: 6px 14px;
    border-radius: 999px;
    font-size: 13px;
    font-weight: 500;
}

.challenge-theme-note {
    margin-top: 20px;
    font-size: 13px;
    color: var(--dark-gray);
    opacity: 0.9;
}

/* ========== 通用：各主题挑战项目列表（ESG/公益/年度/大赛） ========== */
.challenge-list-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;
    margin: 28px 0 16px;
    padding-bottom: 8px;
    border-bottom: 2px solid rgba(0,0,0,0.08);
}

.challenge-list-header .theme-challenge-list-title,
.challenge-list-header .tech-challenge-list-title {
    margin: 0;
    padding-bottom: 0;
    border-bottom: none;
}

.challenge-list-more {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 8px 18px;
    font-size: 14px;
    font-weight: 600;
    color: var(--deep-space-blue);
    background: rgba(62, 146, 204, 0.12);
    border: 1px solid rgba(62, 146, 204, 0.4);
    border-radius: 8px;
    text-decoration: none;
    transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.challenge-list-more:hover {
    background: var(--light-blue);
    color: white;
    border-color: var(--light-blue);
}

.theme-challenge-list-title {
    font-size: 18px;
    font-weight: 700;
    margin: 28px 0 16px;
    padding-bottom: 8px;
    border-bottom: 2px solid rgba(0,0,0,0.08);
}

.theme-challenge-list {
    margin-bottom: 24px;
}

/* 真境挑战卡片使用项目页 student-list-card 样式，以下为各主题配色覆盖 */
/* ESG 主题 - 绿色系 */
.challenge-theme-esg .challenge-list-header { border-bottom-color: rgba(76, 175, 80, 0.4); }
.challenge-theme-esg .theme-challenge-list-title { color: #1b5e20; }
.challenge-theme-esg .challenge-list-more { color: #2e7d32; background: rgba(76, 175, 80, 0.12); border-color: rgba(76, 175, 80, 0.4); }
.challenge-theme-esg .challenge-list-more:hover { background: #2e7d32; color: white; border-color: #2e7d32; }
.challenge-theme-esg .student-list-card { border-color: rgba(76, 175, 80, 0.25); }
.challenge-theme-esg .student-list-card .card-tag { background: rgba(76, 175, 80, 0.15); color: #2e7d32; border-color: rgba(76, 175, 80, 0.3); }
.challenge-theme-esg .student-list-card .card-title { color: #1b5e20; }
.challenge-theme-esg .student-list-card .card-link-detail { color: #2e7d32; border-color: #2e7d32; }
.challenge-theme-esg .student-list-card .card-link-detail:hover { background: rgba(76, 175, 80, 0.1); }
.challenge-theme-esg .student-list-card .card-link-study {
    background: linear-gradient(135deg, #4CAF50 0%, #2E7D32 100%);
    color: #fff;
    box-shadow: 0 2px 8px rgba(76, 175, 80, 0.3);
}
.challenge-theme-esg .student-list-card .card-link-study:hover {
    background: linear-gradient(135deg, #43A047 0%, #1B5E20 100%);
}

/* 公益主题卡片 */
.challenge-theme-charity .challenge-list-header { border-bottom-color: rgba(255, 152, 0, 0.4); }
.challenge-theme-charity .theme-challenge-list-title { color: #bf360c; }
.challenge-theme-charity .challenge-list-more { color: #e65100; background: rgba(255, 152, 0, 0.15); border-color: rgba(255, 152, 0, 0.4); }
.challenge-theme-charity .challenge-list-more:hover { background: #e65100; color: white; border-color: #e65100; }
.challenge-theme-charity .student-list-card { border-color: rgba(255, 152, 0, 0.3); }
.challenge-theme-charity .student-list-card .card-tag { background: rgba(255, 152, 0, 0.15); color: #e65100; border-color: rgba(255, 152, 0, 0.3); }
.challenge-theme-charity .student-list-card .card-title { color: #bf360c; }
.challenge-theme-charity .student-list-card .card-link-detail { color: #e65100; border-color: #e65100; }
.challenge-theme-charity .student-list-card .card-link-detail:hover { background: rgba(255, 152, 0, 0.1); }
.challenge-theme-charity .student-list-card .card-link-study {
    background: linear-gradient(135deg, #ff9800 0%, #e65100 100%);
    color: #fff;
    box-shadow: 0 2px 8px rgba(230, 81, 0, 0.3);
}
.challenge-theme-charity .student-list-card .card-link-study:hover {
    background: linear-gradient(135deg, #f57c00 0%, #bf360c 100%);
}

/* 年度终极主题卡片 */
.challenge-theme-annual .challenge-list-header { border-bottom-color: rgba(103, 58, 183, 0.4); }
.challenge-theme-annual .theme-challenge-list-title { color: #4527a0; }
.challenge-theme-annual .challenge-list-more { color: #5e35b1; background: rgba(103, 58, 183, 0.12); border-color: rgba(103, 58, 183, 0.4); }
.challenge-theme-annual .challenge-list-more:hover { background: #5e35b1; color: white; border-color: #5e35b1; }
.challenge-theme-annual .student-list-card { border-color: rgba(103, 58, 183, 0.3); }
.challenge-theme-annual .student-list-card .card-tag { background: rgba(103, 58, 183, 0.15); color: #5e35b1; border-color: rgba(103, 58, 183, 0.3); }
.challenge-theme-annual .student-list-card .card-title { color: #4527a0; }
.challenge-theme-annual .student-list-card .card-link-detail { color: #5e35b1; border-color: #5e35b1; }
.challenge-theme-annual .student-list-card .card-link-detail:hover { background: rgba(103, 58, 183, 0.1); }
.challenge-theme-annual .student-list-card .card-link-study {
    background: linear-gradient(135deg, #7e57c2 0%, #5e35b1 100%);
    color: #fff;
    box-shadow: 0 2px 8px rgba(94, 53, 177, 0.3);
}
.challenge-theme-annual .student-list-card .card-link-study:hover {
    background: linear-gradient(135deg, #673ab7 0%, #4527a0 100%);
}

/* 真境大赛主题卡片（深色底）- 增强对比度 */
.challenge-theme-competition .challenge-list-header { border-bottom-color: rgba(255, 215, 0, 0.5); }
.challenge-theme-competition .theme-challenge-list-title { color: #ffd700; }
.challenge-theme-competition .theme-challenge-list-title.competition-challenge-list-title { color: #fff; }
.challenge-theme-competition .challenge-list-more {
    color: #1b263b;
    background: #ffd700;
    border-color: #e6b800;
}
.challenge-theme-competition .challenge-list-more:hover {
    background: #fff;
    color: #1b263b;
    border-color: #e6b800;
}
.challenge-theme-competition .student-list-card { border-color: rgba(255, 215, 0, 0.3); }
.challenge-theme-competition .student-list-card .card-tag {
    background: rgba(255, 193, 7, 0.35);
    color: #b8860b;
    border-color: rgba(184, 134, 11, 0.5);
}
.challenge-theme-competition .student-list-card .card-title { color: #1b263b; }
.challenge-theme-competition .student-list-card .card-tag.tag-alt {
    background: rgba(0,0,0,0.06);
    color: #4a5568;
    border-color: rgba(0,0,0,0.1);
}
.challenge-theme-competition .student-list-card .card-link-detail {
    color: #b8860b;
    border-color: #b8860b;
}
.challenge-theme-competition .student-list-card .card-link-detail:hover {
    background: rgba(255, 193, 7, 0.2);
    color: #8b6914;
}
.challenge-theme-competition .student-list-card .card-link-study {
    background: linear-gradient(135deg, #ffd700 0%, #e6b800 100%);
    color: #1b263b;
    box-shadow: 0 2px 8px rgba(255, 215, 0, 0.4);
    font-weight: 600;
}
.challenge-theme-competition .student-list-card .card-link-study:hover {
    background: linear-gradient(135deg, #fff 0%, #f5e6a3 100%);
}

/* ========== ESG/CSR：绿色可持续、三柱视觉 ========== */
.challenge-theme-esg {
    background: linear-gradient(160deg, #e8f5e9 0%, #f1f8e9 45%, #fff 100%);
    border: 1px solid rgba(76, 175, 80, 0.25);
    box-shadow: 0 8px 32px rgba(56, 142, 60, 0.12);
}

.challenge-theme-esg .challenge-theme-label {
    color: #2e7d32;
}

.challenge-theme-esg h2 {
    color: #1b5e20;
}

.challenge-theme-esg .esg-pillars {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-top: 24px;
}

.challenge-theme-esg .esg-pillar {
    text-align: center;
    padding: 24px 16px;
    border-radius: 16px;
    position: relative;
    overflow: hidden;
}

.challenge-theme-esg .esg-pillar::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
}

.challenge-theme-esg .esg-e {
    background: linear-gradient(180deg, #e8f5e9 0%, #fff 100%);
    border: 1px solid rgba(76, 175, 80, 0.3);
}

.challenge-theme-esg .esg-e::before {
    background: linear-gradient(90deg, #2e7d32, #66bb6a);
}

.challenge-theme-esg .esg-s {
    background: linear-gradient(180deg, #e3f2fd 0%, #fff 100%);
    border: 1px solid rgba(33, 150, 243, 0.3);
}

.challenge-theme-esg .esg-s::before {
    background: linear-gradient(90deg, #1565c0, #42a5f5);
}

.challenge-theme-esg .esg-g {
    background: linear-gradient(180deg, #fff3e0 0%, #fff 100%);
    border: 1px solid rgba(239, 108, 0, 0.3);
}

.challenge-theme-esg .esg-g::before {
    background: linear-gradient(90deg, #e65100, #ff9800);
}

.challenge-theme-esg .esg-pillar-letter {
    display: inline-block;
    width: 48px;
    height: 48px;
    line-height: 48px;
    border-radius: 50%;
    font-size: 22px;
    font-weight: 800;
    color: #fff;
    margin-bottom: 12px;
}

.challenge-theme-esg .esg-e .esg-pillar-letter {
    background: linear-gradient(135deg, #2e7d32, #66bb6a);
    box-shadow: 0 4px 12px rgba(46, 125, 50, 0.4);
}

.challenge-theme-esg .esg-s .esg-pillar-letter {
    background: linear-gradient(135deg, #1565c0, #42a5f5);
    box-shadow: 0 4px 12px rgba(21, 101, 192, 0.4);
}

.challenge-theme-esg .esg-g .esg-pillar-letter {
    background: linear-gradient(135deg, #e65100, #ff9800);
    box-shadow: 0 4px 12px rgba(230, 81, 0, 0.4);
}

.challenge-theme-esg .esg-pillar h3 {
    font-size: 16px;
    color: var(--deep-space-blue);
    margin-bottom: 8px;
}

.challenge-theme-esg .esg-pillar p {
    font-size: 13px;
    color: var(--dark-gray);
    line-height: 1.5;
}

.challenge-theme-esg .highlight-tag {
    background: rgba(76, 175, 80, 0.2);
    color: #2e7d32;
    border: 1px solid rgba(76, 175, 80, 0.4);
}

@media (max-width: 640px) {
    .challenge-theme-esg .esg-pillars {
        grid-template-columns: 1fr;
    }
}

/* ========== 科技创新：流程线、科技蓝 ========== */
.challenge-theme-tech {
    background: linear-gradient(165deg, #e3f2fd 0%, #e8eaf6 40%, #fff 100%);
    border: 1px solid rgba(30, 58, 138, 0.2);
    box-shadow: 0 8px 32px rgba(10, 36, 99, 0.1);
}

.challenge-theme-tech .challenge-theme-label {
    color: var(--dark-blue);
}

.challenge-theme-tech h2 {
    color: var(--deep-space-blue);
}

.challenge-theme-tech .tech-flow {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    gap: 8px 4px;
    margin-top: 28px;
    padding: 24px 16px;
    background: rgba(255,255,255,0.7);
    border-radius: 16px;
    border: 1px dashed rgba(62, 146, 204, 0.4);
}

.challenge-theme-tech .tech-flow-step {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 18px;
    background: linear-gradient(135deg, var(--deep-space-blue), var(--light-blue));
    color: white;
    border-radius: 12px;
    font-size: 14px;
    font-weight: 600;
    box-shadow: 0 4px 14px rgba(10, 36, 99, 0.3);
}

.challenge-theme-tech .tech-step-num {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
    background: rgba(255,255,255,0.25);
    border-radius: 50%;
    font-size: 12px;
}

.challenge-theme-tech .tech-flow-arrow {
    color: var(--light-blue);
    font-size: 18px;
    font-weight: bold;
    opacity: 0.8;
}

.challenge-theme-tech .highlight-tag,
.challenge-theme-tech .tech-tags .highlight-tag {
    background: rgba(62, 146, 204, 0.2);
    color: var(--dark-blue);
    border: 1px solid rgba(62, 146, 204, 0.4);
}

/* 科技创新主题 - 企业发起挑战项目列表 */
.challenge-theme-tech .challenge-list-header { border-bottom-color: rgba(62, 146, 204, 0.4); }
.challenge-theme-tech .challenge-list-header .tech-challenge-list-title { color: var(--deep-space-blue); }
.challenge-theme-tech .challenge-list-more { color: var(--dark-blue); background: rgba(62, 146, 204, 0.12); border-color: rgba(62, 146, 204, 0.4); }
.challenge-theme-tech .challenge-list-more:hover { background: var(--light-blue); color: white; border-color: var(--light-blue); }
.challenge-theme-tech .student-list-card { border-color: rgba(62, 146, 204, 0.25); }

.tech-challenge-list-title {
    font-size: 18px;
    font-weight: 700;
    color: var(--deep-space-blue);
    margin: 0;
    padding-bottom: 0;
    border-bottom: none;
}

.tech-challenge-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
    margin-bottom: 24px;
}

.tech-challenge-card {
    background: rgba(255, 255, 255, 0.9);
    border: 1px solid rgba(62, 146, 204, 0.3);
    border-radius: 14px;
    padding: 20px;
    box-shadow: 0 4px 14px rgba(10, 36, 99, 0.08);
    transition: box-shadow 0.25s ease, transform 0.25s ease;
}

.tech-challenge-card:not(.challenge-card-bg):hover {
    box-shadow: 0 8px 24px rgba(10, 36, 99, 0.15);
    transform: translateY(-2px);
}

.tech-challenge-enterprise {
    display: inline-block;
    font-size: 12px;
    font-weight: 700;
    color: var(--light-blue);
    text-transform: uppercase;
    letter-spacing: 0.04em;
    margin-bottom: 8px;
}

.tech-challenge-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--deep-space-blue);
    margin-bottom: 10px;
    line-height: 1.35;
}

.tech-challenge-desc {
    font-size: 13px;
    color: var(--dark-gray);
    line-height: 1.55;
    margin-bottom: 12px;
}

.tech-challenge-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-bottom: 14px;
}

.tech-challenge-tags span {
    font-size: 11px;
    padding: 4px 10px;
    background: rgba(62, 146, 204, 0.15);
    color: var(--dark-blue);
    border-radius: 999px;
}

.tech-challenge-cta {
    display: inline-block;
    font-size: 13px;
    font-weight: 600;
    color: var(--light-blue);
    text-decoration: none;
    transition: color 0.2s ease;
}

.tech-challenge-cta:hover {
    color: var(--deep-space-blue);
}

@media (max-width: 700px) {
    .challenge-theme-tech .tech-flow-arrow {
        display: none;
    }
    .challenge-theme-tech .tech-flow {
        flex-direction: column;
        gap: 12px;
    }
}

/* ========== 公益挑战：一次作业多次打榜、温暖公益风 ========== */
.challenge-theme-charity {
    background: linear-gradient(160deg, #fff8e1 0%, #ffecb3 30%, #fff 100%);
    border: 1px solid rgba(255, 152, 0, 0.25);
    box-shadow: 0 8px 32px rgba(245, 124, 0, 0.08);
}

.challenge-theme-charity .challenge-theme-label {
    color: #e65100;
}

.challenge-theme-charity h2 {
    color: #bf360c;
}

.challenge-theme-charity .charity-slogan {
    text-align: center;
    margin: 28px 0 24px;
    padding: 20px 24px;
    background: linear-gradient(135deg, #ff9800, #ff5722);
    border-radius: 16px;
    box-shadow: 0 6px 20px rgba(255, 87, 34, 0.35);
}

.challenge-theme-charity .charity-slogan-text {
    font-size: 20px;
    font-weight: 800;
    color: #fff;
    letter-spacing: 0.04em;
    text-shadow: 0 1px 2px rgba(0,0,0,0.15);
}

.challenge-theme-charity .charity-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.challenge-theme-charity .charity-list li {
    position: relative;
    padding: 14px 20px 14px 44px;
    margin-bottom: 10px;
    background: rgba(255,255,255,0.85);
    border-radius: 12px;
    border-left: 4px solid #ff9800;
    font-size: 14px;
    color: var(--dark-gray);
    line-height: 1.5;
}

.challenge-theme-charity .charity-list li::before {
    content: '♥';
    position: absolute;
    left: 18px;
    color: #ff5722;
    font-size: 16px;
}

.challenge-theme-charity .charity-list strong {
    color: #e65100;
}

/* ========== 年度终极挑战：三角导师、证书/实习/升学 ========== */
.challenge-theme-annual {
    background: linear-gradient(160deg, #f3e5f5 0%, #ede7f6 40%, #fff 100%);
    border: 1px solid rgba(103, 58, 183, 0.25);
    box-shadow: 0 8px 32px rgba(103, 58, 183, 0.12);
}

.challenge-theme-annual .challenge-theme-label {
    color: #5e35b1;
}

.challenge-theme-annual h2 {
    color: #4527a0;
}

.challenge-theme-annual .annual-triangle {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 20px;
    margin-top: 28px;
}

.challenge-theme-annual .annual-role {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 16px 24px;
    background: white;
    border-radius: 14px;
    font-size: 15px;
    font-weight: 600;
    color: var(--deep-space-blue);
    border: 2px solid rgba(103, 58, 183, 0.3);
    box-shadow: 0 4px 14px rgba(103, 58, 183, 0.12);
}

.challenge-theme-annual .annual-role-icon {
    font-size: 24px;
}

.challenge-theme-annual .annual-cta {
    text-align: center;
    font-size: 15px;
    font-weight: 700;
    color: #5e35b1;
    margin: 20px 0 16px;
}

.challenge-theme-annual .annual-rewards {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 12px;
}

.challenge-theme-annual .annual-rewards span {
    padding: 10px 20px;
    background: linear-gradient(135deg, #7e57c2, #b39ddb);
    color: white;
    border-radius: 999px;
    font-size: 14px;
    font-weight: 600;
    box-shadow: 0 4px 12px rgba(126, 87, 194, 0.35);
}

/* ========== 真境挑战大赛：三色环、赛季制、区块链 ========== */
.challenge-theme-competition {
    background: linear-gradient(160deg, #0d1b2a 0%, #1b263b 35%, #415a77 100%);
    border: 1px solid rgba(255, 215, 0, 0.2);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.25);
    color: #e0e1dd;
}

.challenge-theme-competition .challenge-theme-label {
    color: #ffd700;
    text-shadow: 0 0 8px rgba(255, 215, 0, 0.35);
}

.challenge-theme-competition h2 {
    color: #fff;
}

.challenge-theme-competition .challenge-theme-lead {
    color: rgba(255,255,255,0.95);
}

.challenge-theme-competition .challenge-theme-body {
    margin-top: 24px;
}

.challenge-theme-competition .competition-rings {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    gap: 12px 8px;
    margin-top: 24px;
}

.challenge-theme-competition .ring {
    padding: 14px 22px;
    border-radius: 12px;
    font-size: 14px;
    font-weight: 700;
    color: #1b263b;
    min-width: 100px;
    text-align: center;
}

.challenge-theme-competition .ring-school {
    background: linear-gradient(135deg, #4ade80, #22c55e);
    box-shadow: 0 4px 14px rgba(34, 197, 94, 0.4);
}

.challenge-theme-competition .ring-enterprise {
    background: linear-gradient(135deg, #60a5fa, #3b82f6);
    box-shadow: 0 4px 14px rgba(59, 130, 246, 0.4);
}

.challenge-theme-competition .ring-university {
    background: linear-gradient(135deg, #fbbf24, #f59e0b);
    box-shadow: 0 4px 14px rgba(245, 158, 11, 0.4);
}

.challenge-theme-competition .ring-arrow {
    color: #ffd700;
    font-size: 20px;
    font-weight: bold;
}

.challenge-theme-competition .competition-rings-desc {
    text-align: center;
    font-size: 14px;
    color: #ffd700;
    margin-top: 16px;
    font-weight: 600;
}

.challenge-theme-competition .competition-features {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 20px;
}

.challenge-theme-competition .competition-feature {
    padding: 8px 16px;
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 215, 0, 0.5);
    border-radius: 999px;
    font-size: 13px;
    color: #fff;
}

.challenge-theme-competition .challenge-theme-note {
    color: rgba(255,255,255,0.95);
}

@media (max-width: 600px) {
    .challenge-theme-competition .ring-arrow {
        display: none;
    }
    .challenge-theme-competition .competition-rings {
        flex-direction: column;
    }
}

/* Hero 微调：确保角色卡片可见 */
.challenge-hero {
    overflow: visible;
}

.challenge-hero .container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

.challenge-hero h1 {
    font-size: 32px;
}

.challenge-hero p {
    font-size: 15px;
}