/* preliminary.css
 * 仅用于 0-preliminary.html 的页面级组件样式
 */

/* Java 路线图：用纯 HTML/CSS 替代静态大图，提升响应式体验 */
.java-roadmap {
    margin-top: 26px;
    padding: 26px 24px 16px;
    border-radius: 22px;
    border: 1px solid rgba(138, 74, 18, 0.16);
    background:
        radial-gradient(circle at 12% 12%, rgba(208, 101, 25, 0.08), transparent 28%),
        radial-gradient(circle at 88% 88%, rgba(2, 132, 199, 0.08), transparent 24%),
        linear-gradient(180deg, #fffefb 0%, #f8f2e8 100%);
    box-shadow: 0 14px 30px rgba(74, 52, 37, 0.12);
}

.roadmap-grid {
    display: grid;
    grid-template-columns: repeat(5, minmax(130px, 1fr));
    grid-template-rows: repeat(2, auto);
    align-items: center;
    gap: 18px 28px;
}

.roadmap-node {
    position: relative;
    min-height: 92px;
    padding: 14px 14px 12px;
    border-radius: 14px;
    border: 1px solid rgba(138, 74, 18, 0.2);
    background: linear-gradient(160deg, #ffffff 0%, #f5efe4 100%);
    box-shadow: 0 8px 18px rgba(62, 45, 33, 0.10);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.roadmap-node:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 20px rgba(62, 45, 33, 0.14);
}

.roadmap-node h3 {
    margin: 0;
    font-size: 1.1em;
    color: var(--accent-color);
    line-height: 1.25;
}

.roadmap-node p {
    margin: 8px 0 0;
    font-size: 0.9em;
    line-height: 1.45;
    color: #5a4638;
}

/* 节点定位：桌面端采用双行蛇形路线 */
.roadmap-node--se { grid-column: 1; grid-row: 1 / span 2; }
.roadmap-node--web { grid-column: 2; grid-row: 1; }
.roadmap-node--jvm { grid-column: 2; grid-row: 2; }
.roadmap-node--ssm { grid-column: 3; grid-row: 1; }
.roadmap-node--concurrent { grid-column: 3; grid-row: 2; }
.roadmap-node--boot { grid-column: 4; grid-row: 1; }
.roadmap-node--nio { grid-column: 4; grid-row: 2; }
.roadmap-node--cloud { grid-column: 5; grid-row: 1 / span 2; }

/* 水平方向连接线 */
.roadmap-node--web::before,
.roadmap-node--jvm::before,
.roadmap-node--ssm::before,
.roadmap-node--concurrent::before,
.roadmap-node--boot::before,
.roadmap-node--nio::before,
.roadmap-node--cloud::before {
    content: "";
    position: absolute;
    left: -30px;
    top: 50%;
    width: 30px;
    border-top: 2px dashed rgba(208, 101, 25, 0.62);
}

/* 左侧一分二：拉长 Web/JVM 入线，让其直接从 Java SE 右侧出发 */
.roadmap-node--web::before,
.roadmap-node--jvm::before {
    left: -50px;
    width: 50px;
}

/* 节点入点的小箭头 */
.roadmap-node--web::after,
.roadmap-node--jvm::after,
.roadmap-node--ssm::after,
.roadmap-node--concurrent::after,
.roadmap-node--boot::after,
.roadmap-node--nio::after,
.roadmap-node--cloud::after {
    content: "";
    position: absolute;
    left: -8px;
    top: calc(50% - 4px);
    border-top: 4px solid transparent;
    border-bottom: 4px solid transparent;
    border-left: 6px solid rgba(208, 101, 25, 0.85);
}

/* 左侧主干节点向上/向下分叉 */
.roadmap-node--se::before,
.roadmap-node--se::after {
    /* 关闭 Java SE 额外分叉线，避免出现第三条悬空线 */
    display: none;
}

/* 右侧汇聚节点，视觉上承接上下两条路线 */
.roadmap-node--cloud {
    border-color: rgba(2, 132, 199, 0.28);
    background: linear-gradient(160deg, #fdfefe 0%, #ebf6fb 100%);
}

.roadmap-node--cloud h3 {
    color: #0b598e;
}

.roadmap-caption {
    margin: 16px 0 2px;
    font-size: 0.96em;
    color: #6b5342;
    text-align: center;
}

/* 平板与手机：切换为单列，连线改为纵向，保证可读性 */
@media (max-width: 1024px) {
    .roadmap-grid {
        grid-template-columns: 1fr;
        grid-template-rows: auto;
        gap: 14px;
    }

    .roadmap-node {
        min-height: 0;
    }

    .roadmap-node--se,
    .roadmap-node--web,
    .roadmap-node--jvm,
    .roadmap-node--ssm,
    .roadmap-node--concurrent,
    .roadmap-node--boot,
    .roadmap-node--nio,
    .roadmap-node--cloud {
        grid-column: 1;
        grid-row: auto;
    }

    .roadmap-node::before,
    .roadmap-node::after {
        display: none;
    }

    .roadmap-node + .roadmap-node {
        margin-top: 10px;
    }
}