:root {
    --page-background: #ffffff;
    --soft-background: #f7f8fa;
    --border: #e9edf3;
    --timeline: #e9edf2;
    --text: #303642;
    --muted: #8d96a5;
    --blue: #3b82f6;
    --blue-soft: #eaf2ff;
    --add: #4b8df8;
    --add-background: #eef5ff;
    --optimize: #e89020;
    --optimize-background: #fff6e8;
    --repair: #48b978;
    --repair-background: #ecfbf2;
    --content-width: 1450px;
}

* {
    box-sizing: border-box;
}

html {
    min-width: 320px;
    background: var(--page-background);
    color: var(--text);
    font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", Arial, sans-serif;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
}

body {
    min-height: 100vh;
    margin: 0;
    background: var(--page-background);
}

button,
input {
    font: inherit;
}

button,
a,
input {
    -webkit-tap-highlight-color: transparent;
}

button:focus-visible,
a:focus-visible,
input:focus-visible {
    outline: 3px solid rgba(59, 130, 246, 0.22);
    outline-offset: 2px;
}

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.page-header {
    border-top: 7px solid #f5f6f8;
    border-bottom: 1px solid var(--border);
    background: rgba(255, 255, 255, 0.98);
}

.header-shell,
.content-toolbar,
.timeline {
    width: min(calc(100% - 80px), var(--content-width));
    margin-inline: auto;
}

.header-shell {
    padding: 28px 0 18px;
}

.header-topline {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 40px;
}

.heading-group {
    display: flex;
    align-items: baseline;
    min-width: 0;
    gap: 16px;
}

.heading-group h1 {
    margin: 0;
    color: #252b35;
    font-size: clamp(30px, 2.5vw, 42px);
    font-weight: 720;
    line-height: 1.2;
    letter-spacing: -0.03em;
}

.heading-subtitle {
    color: #6f7886;
    font-size: 18px;
    white-space: nowrap;
}

.platform-domain {
    color: var(--muted);
    font-size: 14px;
    text-decoration: none;
    white-space: nowrap;
}

.platform-domain:hover {
    color: var(--blue);
}

.search-form {
    display: flex;
    flex: 0 1 470px;
    min-width: 320px;
    gap: 12px;
}

.search-form input {
    width: 100%;
    min-width: 0;
    height: 46px;
    padding: 0 16px;
    color: var(--text);
    background: #ffffff;
    border: 1px solid #dfe5ed;
    border-radius: 7px;
    transition: border-color 160ms ease, box-shadow 160ms ease;
}

.search-form input::placeholder {
    color: #a0a8b5;
}

.search-form input:hover,
.search-form input:focus {
    border-color: #91b7f8;
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.08);
}

.search-form button {
    flex: 0 0 92px;
    height: 46px;
    color: #ffffff;
    font-weight: 600;
    background: var(--blue);
    border: 0;
    border-radius: 7px;
    cursor: pointer;
    transition: background 160ms ease, transform 160ms ease;
}

.search-form button:hover {
    background: #2f73dd;
}

.search-form button:active {
    transform: translateY(1px);
}

.header-controls {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
    margin-top: 26px;
}

.platform-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
}

.platform-tab {
    min-height: 44px;
    padding: 0 24px;
    color: #555f6e;
    font-size: 16px;
    font-weight: 560;
    background: #f3f4f6;
    border: 1px solid transparent;
    border-radius: 7px;
    cursor: pointer;
    transition: color 160ms ease, background 160ms ease, border-color 160ms ease;
}

.platform-tab:hover {
    color: var(--blue);
    border-color: #cfe0fb;
}

.platform-tab.is-active {
    color: #2d73df;
    background: var(--blue-soft);
    border-color: #d7e5fb;
}

.record-summary {
    margin: 0;
    color: #7d8795;
    font-size: 15px;
    white-space: nowrap;
}

.page-main {
    min-height: calc(100vh - 190px);
    overflow: hidden;
}

.content-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
    min-height: 68px;
    border-bottom: 1px solid #f0f2f5;
}

.type-filters {
    display: flex;
    gap: 8px;
}

.type-filter {
    min-width: 54px;
    height: 32px;
    padding: 0 12px;
    color: #788290;
    font-size: 14px;
    background: #ffffff;
    border: 1px solid #e2e6ec;
    border-radius: 999px;
    cursor: pointer;
}

.type-filter:hover,
.type-filter.is-active {
    color: var(--blue);
    background: #f2f7ff;
    border-color: #bcd4fb;
}

.history-range {
    margin: 0;
    color: #a0a7b1;
    font-size: 13px;
}

.timeline {
    position: relative;
    padding: 46px 0 112px 106px;
}

.timeline::before {
    content: "";
    position: absolute;
    top: 0;
    bottom: 0;
    left: 48px;
    width: 1px;
    background: var(--timeline);
}

.release {
    position: relative;
    margin: 0 0 62px;
}

.release:last-child {
    margin-bottom: 0;
}

.release::before {
    content: "";
    position: absolute;
    top: 10px;
    left: -65px;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: var(--blue);
    box-shadow: 0 0 0 5px #ffffff;
}

.release-date {
    margin: 0;
    color: #505865;
    font-size: 25px;
    font-weight: 650;
    line-height: 1.35;
    letter-spacing: 0.01em;
}

.release-summary {
    margin: 7px 0 0;
    color: var(--muted);
    font-size: 15px;
    line-height: 1.5;
}

.change-list {
    display: grid;
    gap: 12px;
    margin: 24px 0 0;
    padding: 0;
    list-style: none;
}

.change-item {
    display: flex;
    align-items: flex-start;
    min-width: 0;
}

.change-tag {
    flex: 0 0 50px;
    min-height: 27px;
    margin: 0 22px 0 0;
    padding: 2px 6px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    font-size: 14px;
    line-height: 23px;
    white-space: nowrap;
}

.change-tag--add {
    color: var(--add);
    background: var(--add-background);
}

.change-tag--optimize {
    color: var(--optimize);
    background: var(--optimize-background);
}

.change-tag--repair {
    color: var(--repair);
    background: var(--repair-background);
}

.change-text {
    min-width: 0;
    max-width: 1060px;
    color: #434b57;
    font-size: 17px;
    line-height: 1.62;
    overflow-wrap: anywhere;
}

.empty-state {
    margin: 110px 24px;
    color: var(--muted);
    font-size: 16px;
    text-align: center;
}

@media (max-width: 980px) {
    .header-shell,
    .content-toolbar,
    .timeline {
        width: min(calc(100% - 48px), var(--content-width));
    }

    .header-topline {
        align-items: flex-start;
        flex-direction: column;
        gap: 22px;
    }

    .search-form {
        width: 100%;
        max-width: none;
        flex-basis: auto;
    }

    .header-controls {
        align-items: flex-start;
        flex-direction: column;
        gap: 16px;
    }

    .record-summary {
        white-space: normal;
    }
}

@media (max-width: 680px) {
    .header-shell,
    .content-toolbar,
    .timeline {
        width: calc(100% - 32px);
    }

    .header-shell {
        padding: 22px 0 16px;
    }

    .heading-group {
        align-items: flex-start;
        flex-wrap: wrap;
        gap: 6px 10px;
    }

    .heading-group h1 {
        flex-basis: 100%;
        font-size: 28px;
    }

    .heading-subtitle {
        font-size: 16px;
    }

    .search-form {
        min-width: 0;
        gap: 8px;
    }

    .search-form input,
    .search-form button {
        height: 44px;
    }

    .search-form button {
        flex-basis: 72px;
    }

    .platform-tabs {
        width: 100%;
        flex-direction: column;
        gap: 8px;
    }

    .platform-tab {
        width: 100%;
        text-align: left;
    }

    .content-toolbar {
        align-items: flex-start;
        flex-direction: column;
        padding: 16px 0;
        gap: 12px;
    }

    .type-filters {
        width: 100%;
        overflow-x: auto;
        padding-bottom: 2px;
    }

    .history-range {
        line-height: 1.5;
    }

    .timeline {
        padding: 36px 0 72px 40px;
    }

    .timeline::before {
        left: 8px;
    }

    .release {
        margin-bottom: 48px;
    }

    .release::before {
        top: 8px;
        left: -38px;
        width: 11px;
        height: 11px;
        box-shadow: 0 0 0 4px #ffffff;
    }

    .release-date {
        font-size: 21px;
    }

    .release-summary {
        font-size: 14px;
    }

    .change-list {
        gap: 11px;
        margin-top: 19px;
    }

    .change-tag {
        flex-basis: 43px;
        min-height: 24px;
        margin-right: 10px;
        font-size: 12px;
        line-height: 20px;
    }

    .change-text {
        font-size: 15px;
        line-height: 1.58;
    }
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        scroll-behavior: auto !important;
        transition: none !important;
    }
}