:root {
    --bg: #08101f;
    --panel: #111d33;
    --panel-soft: #0d182c;
    --text: #eef3ff;
    --muted: #9fb0d1;
    --line: rgba(255, 255, 255, 0.12);
    --accent: #5d9bff;
    --accent-strong: #7ab0ff;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    background: radial-gradient(circle at 20% 0%, #162846 0%, var(--bg) 45%);
    color: var(--text);
    font-family: "Inter", "PingFang SC", "Microsoft YaHei", sans-serif;
    line-height: 1.5;
}

.ai-history-page {
    width: min(1400px, 100%);
    margin: 0 auto;
    padding: 28px clamp(16px, 4vw, 40px) 52px;
    display: grid;
    gap: 20px;
}

.hero,
.controls,
.year-nav,
.timeline,
.keyword-index {
    background: rgba(12, 20, 35, 0.85);
    border: 1px solid var(--line);
    border-radius: 18px;
}

.hero {
    padding: 24px;
}

.hero h1 {
    margin: 6px 0 10px;
    font-size: clamp(1.5rem, 3.4vw, 2.2rem);
}

.hero__kicker {
    margin: 0;
    color: var(--muted);
    font-size: 0.86rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.hero__desc {
    margin: 0 0 14px;
    max-width: 920px;
    color: #d4def4;
}

.hero__stats {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.chip {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 12px;
    border-radius: 999px;
    background: rgba(93, 155, 255, 0.12);
    border: 1px solid rgba(93, 155, 255, 0.26);
}

.chip strong {
    font-size: 1rem;
    color: #e8f1ff;
}

.chip span {
    font-size: 0.86rem;
    color: #cadeff;
}

.controls {
    padding: 16px;
    display: grid;
    gap: 12px;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
}

.control {
    display: grid;
    gap: 6px;
}

.control--grow {
    grid-column: span 2;
}

.control label {
    color: var(--muted);
    font-size: 0.84rem;
}

select,
input[type="search"] {
    width: 100%;
    border-radius: 10px;
    border: 1px solid var(--line);
    background: var(--panel-soft);
    color: var(--text);
    padding: 10px 12px;
}

.year-nav {
    padding: 12px;
    display: grid;
    grid-template-columns: auto 1fr auto;
    gap: 10px;
    align-items: center;
}

.year-tabs {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    padding-bottom: 2px;
}

button {
    border-radius: 10px;
    border: 1px solid var(--line);
    background: var(--panel-soft);
    color: var(--text);
    padding: 10px 12px;
    cursor: pointer;
}

button:hover:not(:disabled) {
    border-color: rgba(122, 176, 255, 0.5);
    color: var(--accent-strong);
}

button.active {
    background: rgba(93, 155, 255, 0.2);
    border-color: rgba(93, 155, 255, 0.54);
    color: #eef5ff;
}

button:disabled {
    opacity: 0.45;
    cursor: not-allowed;
}

.timeline {
    padding: 16px;
    display: grid;
    gap: 16px;
}

.year-section {
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 12px;
    background: rgba(17, 29, 51, 0.45);
}

.year-section__title {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    margin-bottom: 10px;
    gap: 10px;
}

.year-section__title h2 {
    margin: 0;
    font-size: 1.2rem;
}

.year-section__title p {
    margin: 0;
    color: var(--muted);
    font-size: 0.9rem;
}

.event-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 10px;
}

.event-card {
    border-radius: 12px;
    border: 1px solid var(--line);
    padding: 12px;
    background: rgba(9, 17, 31, 0.8);
    display: grid;
    gap: 10px;
}

.event-card__head {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 8px;
}

.event-card__head h3 {
    margin: 0;
    font-size: 1rem;
}

.event-card__year {
    margin: 0;
    color: var(--accent-strong);
    font-size: 0.86rem;
}

.event-card__note {
    margin: 0;
    color: #d0dcf6;
    font-size: 0.92rem;
}

.meta-block {
    display: grid;
    gap: 6px;
}

.meta-title {
    margin: 0;
    color: var(--muted);
    font-size: 0.8rem;
}

.tag-list {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.tag-list span {
    padding: 4px 8px;
    border-radius: 999px;
    font-size: 0.75rem;
    background: rgba(93, 155, 255, 0.13);
    border: 1px solid rgba(93, 155, 255, 0.25);
}

.empty-state {
    margin: 0;
    padding: 18px;
    border-radius: 10px;
    color: var(--muted);
    border: 1px dashed var(--line);
    background: rgba(7, 13, 24, 0.6);
}

.keyword-index {
    padding: 16px;
    display: grid;
    gap: 16px;
}

.keyword-controls {
    display: grid;
    grid-template-columns: minmax(260px, 1fr);
    gap: 10px;
}

.section-title h2 {
    margin: 0;
}

.section-title p {
    margin: 4px 0 0;
    color: var(--muted);
}

.keyword-groups {
    display: grid;
    gap: 12px;
}

.keyword-group {
    border: 1px solid var(--line);
    border-radius: 12px;
    background: rgba(8, 15, 27, 0.75);
    padding: 12px;
    display: grid;
    gap: 10px;
}

.keyword-group h3 {
    margin: 0;
    font-size: 1rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
}

.keyword-group h3 small,
.keyword-section h4 small {
    color: var(--muted);
    font-size: 0.78rem;
    font-weight: 500;
}

.keyword-section {
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 10px;
    background: rgba(12, 23, 39, 0.6);
    padding: 10px;
    display: grid;
    gap: 8px;
}

.keyword-section h4 {
    margin: 0;
    font-size: 0.94rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
}

.keyword-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.keyword-tags span {
    display: inline-flex;
    align-items: center;
    font-size: 0.74rem;
    padding: 3px 8px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.12);
    color: #deebff;
    line-height: 1.45;
}

.keyword-tags mark {
    background: rgba(122, 176, 255, 0.35);
    color: #ffffff;
    border-radius: 4px;
    padding: 0 2px;
}

@media (max-width: 900px) {
    .control--grow {
        grid-column: span 1;
    }

    .year-nav {
        grid-template-columns: 1fr;
    }

    .year-nav > button {
        width: 100%;
    }
}