/**
 * 全国手帐漂流计划 · 数字档案馆样式
 * 设计原则：文学感、人文档案、旧书桌氛围
 * 字体：16-18px正文，行距1.9-2.15，不压缩字体
 */

/* ========================================
   CSS Variables
   ======================================== */
:root {
    /* 色彩系统 - 暖纸张体系 */
    --drift-color-bg: #F4EFE4;
    --drift-color-bg-warm: #EEE6D7;
    --drift-color-bg-paper: #E5DCCB;
    --drift-color-text: #302820;
    --drift-color-text-secondary: #70665B;
    --drift-color-text-muted: #8B7B6B;
    --drift-color-accent: #8B7355;
    --drift-color-accent-light: #C79643;
    --drift-color-border: #D4C8B8;
    --drift-color-shadow: rgba(48, 40, 32, 0.12);

    /* 字体系统 */
    --drift-font-serif: 'Noto Serif SC', 'Source Han Serif SC', 'SimSun', serif;
    --drift-font-sans: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'PingFang SC', sans-serif;

    /* 字号系统 */
    --drift-text-xs: 11px;
    --drift-text-sm: 13px;
    --drift-text-base: 16px;
    --drift-text-lg: 18px;
    --drift-text-xl: 22px;
    --drift-text-2xl: 28px;
    --drift-text-3xl: 36px;

    /* 间距系统 */
    --drift-space-1: 4px;
    --drift-space-2: 8px;
    --drift-space-3: 12px;
    --drift-space-4: 16px;
    --drift-space-5: 24px;
    --drift-space-6: 32px;
    --drift-space-8: 48px;
    --drift-space-10: 64px;
    --drift-space-12: 96px;

    /* 圆角 */
    --drift-radius-sm: 4px;
    --drift-radius-md: 8px;
    --drift-radius-lg: 12px;

    /* 过渡 */
    --drift-transition-fast: 150ms ease;
    --drift-transition-base: 280ms ease;
    --drift-transition-slow: 420ms ease;

    /* 阴影 */
    --drift-shadow-sm: 0 1px 3px var(--drift-color-shadow);
    --drift-shadow-md: 0 4px 12px var(--drift-color-shadow);
    --drift-shadow-lg: 0 8px 32px var(--drift-color-shadow);

    /* Z-index */
    --drift-z-base: 1;
    --drift-z-modal: 100;
    --drift-z-lightbox: 200;
}

/* ========================================
   Base Reset & Global Styles
   ======================================== */
.drift-archive-page {
    min-height: 100vh;
    background-color: var(--drift-color-bg);
    color: var(--drift-color-text);
    font-family: var(--drift-font-serif);
    font-size: var(--drift-text-base);
    line-height: 1.9;
    letter-spacing: 0.02em;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.drift-archive-page *,
.drift-archive-page *::before,
.drift-archive-page *::after {
    box-sizing: border-box;
}

/* ========================================
   Loading Overlay
   ======================================== */
.drift-loading {
    position: fixed;
    inset: 0;
    background: var(--drift-color-bg);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    transition: opacity var(--drift-transition-slow);
}

.drift-loading.is-hidden {
    opacity: 0;
    pointer-events: none;
}

.drift-loading__inner {
    text-align: center;
}

.drift-loading__book {
    width: 60px;
    height: 80px;
    margin: 0 auto var(--drift-space-5);
    background: linear-gradient(135deg, var(--drift-color-bg-paper) 0%, var(--drift-color-bg-warm) 100%);
    border-radius: 2px 6px 6px 2px;
    position: relative;
    box-shadow: var(--drift-shadow-md);
    animation: bookFloat 2s ease-in-out infinite;
}

.drift-loading__book::before {
    content: '';
    position: absolute;
    left: 4px;
    top: 8px;
    bottom: 8px;
    width: 2px;
    background: var(--drift-color-accent);
    opacity: 0.4;
}

.drift-loading__text {
    color: var(--drift-color-text-secondary);
    font-size: var(--drift-text-sm);
    animation: textPulse 1.5s ease-in-out infinite;
}

@keyframes bookFloat {
    0%, 100% { transform: translateY(0) rotate(-2deg); }
    50% { transform: translateY(-8px) rotate(2deg); }
}

@keyframes textPulse {
    0%, 100% { opacity: 0.6; }
    50% { opacity: 1; }
}

/* ========================================
   Container
   ======================================== */
.drift-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--drift-space-5);
}

/* ========================================
   Header
   ======================================== */
.drift-header {
    padding: var(--drift-space-8) 0 var(--drift-space-6);
    text-align: center;
    border-bottom: 1px solid var(--drift-color-border);
}

.drift-header__back {
    display: inline-flex;
    align-items: center;
    gap: var(--drift-space-2);
    color: var(--drift-color-text-secondary);
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-sm);
    text-decoration: none;
    transition: color var(--drift-transition-fast);
    margin-bottom: var(--drift-space-6);
}

.drift-header__back:hover {
    color: var(--drift-color-accent);
}

.drift-header__title {
    font-size: var(--drift-text-3xl);
    font-weight: 600;
    letter-spacing: 0.1em;
    margin: 0 0 var(--drift-space-4);
    color: var(--drift-color-text);
}

.drift-header__subtitle {
    display: flex;
    flex-direction: column;
    gap: var(--drift-space-1);
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-sm);
    color: var(--drift-color-text-muted);
    letter-spacing: 0.05em;
}

/* ========================================
   Hero Section
   ======================================== */
.drift-hero {
    position: relative;
    height: 400px;
    margin: var(--drift-space-8) 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

.drift-hero__canvas {
    position: absolute;
    inset: 0;
    z-index: 0;
}

.drift-hero__canvas canvas {
    width: 100%;
    height: 100%;
}

.drift-hero__content {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: var(--drift-space-6);
}

.drift-hero__motto {
    font-size: var(--drift-text-xl);
    color: var(--drift-color-text);
    margin: 0 0 var(--drift-space-6);
    text-shadow: 0 1px 2px rgba(255,255,255,0.8);
}

.drift-hero__hint {
    position: absolute;
    bottom: var(--drift-space-4);
    left: 0;
    right: 0;
    display: flex;
    justify-content: center;
    gap: var(--drift-space-6);
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-xs);
    color: var(--drift-color-text-muted);
    opacity: 0.7;
}

/* ========================================
   Buttons
   ======================================== */
.drift-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--drift-space-2);
    padding: var(--drift-space-3) var(--drift-space-5);
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-base);
    font-weight: 500;
    border: none;
    border-radius: var(--drift-radius-md);
    cursor: pointer;
    transition: all var(--drift-transition-base);
    text-decoration: none;
}

.drift-btn--primary {
    background: var(--drift-color-accent);
    color: #fff;
    box-shadow: var(--drift-shadow-md);
}

.drift-btn--primary:hover {
    background: #7A6548;
    transform: translateY(-2px);
    box-shadow: var(--drift-shadow-lg);
}

.drift-btn--secondary {
    background: var(--drift-color-bg-warm);
    color: var(--drift-color-text);
    border: 1px solid var(--drift-color-border);
}

.drift-btn--secondary:hover {
    background: var(--drift-color-bg-paper);
}

.drift-btn--ghost {
    background: transparent;
    color: var(--drift-color-text-secondary);
}

.drift-btn--ghost:hover {
    background: var(--drift-color-bg-warm);
    color: var(--drift-color-text);
}

.drift-btn--open {
    padding: var(--drift-space-4) var(--drift-space-8);
    font-size: var(--drift-text-lg);
}

/* ========================================
   Stats Section
   ======================================== */
.drift-stats {
    padding: var(--drift-space-8) 0;
    border-bottom: 1px solid var(--drift-color-border);
}

.drift-stats__inner {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--drift-space-5);
}

.drift-stat {
    text-align: center;
    padding: var(--drift-space-5);
    background: var(--drift-color-bg-warm);
    border-radius: var(--drift-radius-md);
}

.drift-stat__number {
    display: block;
    font-size: var(--drift-text-3xl);
    font-weight: 600;
    color: var(--drift-color-accent);
    line-height: 1.2;
    margin-bottom: var(--drift-space-2);
}

.drift-stat__label {
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-sm);
    color: var(--drift-color-text-secondary);
}

/* ========================================
   Section Common Styles
   ======================================== */
.drift-section__header {
    text-align: center;
    margin-bottom: var(--drift-space-8);
}

.drift-section__title {
    font-size: var(--drift-text-2xl);
    font-weight: 600;
    margin: 0 0 var(--drift-space-2);
}

.drift-section__desc {
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-sm);
    color: var(--drift-color-text-muted);
    margin: 0;
}

/* ========================================
   Route Section
   ======================================== */
.drift-route {
    padding: var(--drift-space-10) 0;
    border-bottom: 1px solid var(--drift-color-border);
}

.drift-route__timeline {
    max-width: 600px;
    margin: 0 auto;
    padding: var(--drift-space-4) 0;
}

.drift-timeline-item {
    position: relative;
    padding: var(--drift-space-4);
    margin-bottom: var(--drift-space-5);
    background: var(--drift-color-bg-warm);
    border-radius: var(--drift-radius-md);
    transition: all var(--drift-transition-base);
    width: 80%;
}

.drift-timeline-item:nth-child(odd) {
    margin-right: auto;
    margin-left: 0;
}

.drift-timeline-item:nth-child(even) {
    margin-left: auto;
    margin-right: 0;
}

.drift-timeline-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.drift-timeline-item:last-child {
    margin-bottom: 0;
}

.drift-timeline-item__city {
    font-size: var(--drift-text-lg);
    font-weight: 600;
    color: var(--drift-color-text);
    margin: 0 0 var(--drift-space-1);
}

.drift-timeline-item__reader {
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-sm);
    color: var(--drift-color-text-secondary);
    margin: 0 0 var(--drift-space-1);
}

.drift-timeline-item__date {
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-xs);
    color: var(--drift-color-text-muted);
}

.drift-timeline-item__note {
    font-size: var(--drift-text-sm);
    color: var(--drift-color-text-muted);
    margin: var(--drift-space-2) 0 0;
    font-style: italic;
}

/* ========================================
   Archive List Section
   ======================================== */
.drift-archives {
    padding: var(--drift-space-10) 0;
    border-bottom: 1px solid var(--drift-color-border);
}

.drift-archives__list {
    display: grid;
    gap: var(--drift-space-5);
    margin-bottom: var(--drift-space-6);
}

.drift-archive-card {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: var(--drift-space-5);
    padding: var(--drift-space-5);
    background: var(--drift-color-bg-warm);
    border-radius: var(--drift-radius-md);
    cursor: pointer;
    transition: all var(--drift-transition-base);
    text-align: left;
    border: none;
    width: 100%;
    font-family: inherit;
    font-size: inherit;
}

.drift-archive-card:hover {
    background: var(--drift-color-bg-paper);
    transform: translateX(4px);
    box-shadow: var(--drift-shadow-sm);
}

.drift-archive-card__number {
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-xs);
    color: var(--drift-color-text-muted);
    background: var(--drift-color-bg-paper);
    padding: var(--drift-space-1) var(--drift-space-2);
    border-radius: var(--drift-radius-sm);
    height: fit-content;
}

.drift-archive-card__content {
    min-width: 0;
}

.drift-archive-card__title {
    font-size: var(--drift-text-lg);
    font-weight: 600;
    color: var(--drift-color-text);
    margin: 0 0 var(--drift-space-2);
    line-height: 1.4;
}

.drift-archive-card__meta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--drift-space-3);
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-sm);
    color: var(--drift-color-text-secondary);
    margin-bottom: var(--drift-space-3);
}

.drift-archive-card__meta-item {
    display: flex;
    align-items: center;
    gap: var(--drift-space-1);
}

.drift-archive-card__excerpt {
    font-size: var(--drift-text-sm);
    color: var(--drift-color-text-muted);
    line-height: 1.7;
    margin: 0;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.drift-archive-card__photos {
    display: flex;
    gap: var(--drift-space-2);
    margin-top: var(--drift-space-3);
}

.drift-archive-card__photo-thumb {
    width: 48px;
    height: 48px;
    object-fit: cover;
    border-radius: var(--drift-radius-sm);
    opacity: 0.8;
    transition: opacity var(--drift-transition-fast);
}

.drift-archive-card__photo-thumb:hover {
    opacity: 1;
}

.drift-archives__empty {
    text-align: center;
    padding: var(--drift-space-10);
    color: var(--drift-color-text-muted);
}

.drift-archives__pagination {
    display: flex;
    justify-content: center;
}

/* ========================================
   Footer
   ======================================== */
.drift-footer {
    padding: var(--drift-space-10) 0;
    text-align: center;
}

.drift-footer__motto {
    margin: 0 0 var(--drift-space-4);
    font-style: italic;
}

.drift-footer__motto em {
    display: block;
    font-size: var(--drift-text-lg);
    color: var(--drift-color-text);
}

.drift-footer__motto span {
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-sm);
    color: var(--drift-color-text-muted);
    font-style: normal;
}

.drift-footer__credit {
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-xs);
    color: var(--drift-color-text-muted);
    margin: 0 0 var(--drift-space-4);
}

.drift-footer__link {
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-sm);
    color: var(--drift-color-accent);
    text-decoration: none;
}

.drift-footer__link:hover {
    text-decoration: underline;
}

/* ========================================
   Archive Reader Modal
   ======================================== */
.drift-reader {
    position: fixed;
    inset: 0;
    z-index: var(--drift-z-modal);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--drift-space-5);
}

.drift-reader[hidden] {
    display: none;
}

.drift-reader__backdrop {
    position: absolute;
    inset: 0;
    background: rgba(48, 40, 32, 0.85);
    backdrop-filter: blur(4px);
}

.drift-reader__container {
    position: relative;
    width: 100%;
    max-width: 1000px;
    max-height: 90vh;
    background: var(--drift-color-bg);
    border-radius: var(--drift-radius-lg);
    box-shadow: var(--drift-shadow-lg);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.drift-reader__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--drift-space-4) var(--drift-space-5);
    border-bottom: 1px solid var(--drift-color-border);
    background: var(--drift-color-bg-warm);
}

.drift-reader__meta {
    display: flex;
    align-items: center;
    gap: var(--drift-space-4);
}

.drift-reader__archive-no {
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-xs);
    color: var(--drift-color-text-muted);
    background: var(--drift-color-bg-paper);
    padding: var(--drift-space-1) var(--drift-space-2);
    border-radius: var(--drift-radius-sm);
}

.drift-reader__location {
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-sm);
    color: var(--drift-color-text-secondary);
}

.drift-reader__close {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    color: var(--drift-color-text-secondary);
    transition: all var(--drift-transition-fast);
}

.drift-reader__close:hover {
    background: var(--drift-color-bg-paper);
    color: var(--drift-color-text);
}

.drift-reader__content {
    flex: 1;
    overflow-y: auto;
    padding: var(--drift-space-6);
}

.drift-reader__nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--drift-space-4) var(--drift-space-5);
    border-top: 1px solid var(--drift-color-border);
    background: var(--drift-color-bg-warm);
}

.drift-reader__progress {
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-sm);
    color: var(--drift-color-text-secondary);
}

.drift-reader__progress-sep {
    margin: 0 var(--drift-space-2);
}

/* ========================================
   Spread View (Two-Page Layout)
   ======================================== */
.drift-spread {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--drift-space-6);
    min-height: 400px;
}

.drift-page {
    background: #FFFEF9;
    border-radius: var(--drift-radius-md);
    box-shadow: var(--drift-shadow-sm);
    padding: var(--drift-space-6);
}

.drift-page__inner {
    max-width: 100%;
}

.drift-page__title {
    font-size: var(--drift-text-2xl);
    font-weight: 600;
    line-height: 1.3;
    margin: 0 0 var(--drift-space-4);
    color: var(--drift-color-text);
}

.drift-page__author {
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-sm);
    color: var(--drift-color-text-secondary);
    margin-bottom: var(--drift-space-2);
}

.drift-page__date {
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-xs);
    color: var(--drift-color-text-muted);
    margin-bottom: var(--drift-space-5);
}

.drift-page__body {
    font-size: var(--drift-text-base);
    line-height: 2;
    color: var(--drift-color-text);
}

.drift-page__body p {
    margin: 0 0 var(--drift-space-4);
}

.drift-page__body p:last-child {
    margin-bottom: 0;
}

.drift-page__empty-text {
    color: var(--drift-color-text-muted);
    font-style: italic;
    text-align: center;
    padding: var(--drift-space-8) 0;
}

.drift-page__photos {
    display: flex;
    flex-direction: column;
    gap: var(--drift-space-4);
}

.drift-page__photo {
    width: 100%;
    border-radius: var(--drift-radius-sm);
    cursor: pointer;
    transition: transform var(--drift-transition-fast);
}

.drift-page__photo:hover {
    transform: scale(1.02);
}

.drift-page__empty-photos {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 200px;
    color: var(--drift-color-text-muted);
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-sm);
    text-align: center;
}

/* ========================================
   Image Lightbox
   ======================================== */
.drift-lightbox {
    position: fixed;
    inset: 0;
    z-index: var(--drift-z-lightbox);
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0, 0, 0, 0.95);
}

.drift-lightbox[hidden] {
    display: none;
}

.drift-lightbox__close {
    position: absolute;
    top: var(--drift-space-5);
    right: var(--drift-space-5);
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.1);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    color: #fff;
    transition: background var(--drift-transition-fast);
}

.drift-lightbox__close:hover {
    background: rgba(255, 255, 255, 0.2);
}

.drift-lightbox__image {
    max-width: 90vw;
    max-height: 85vh;
    object-fit: contain;
    border-radius: var(--drift-radius-md);
}

.drift-lightbox__caption {
    position: absolute;
    bottom: var(--drift-space-6);
    left: 50%;
    transform: translateX(-50%);
    font-family: var(--drift-font-sans);
    font-size: var(--drift-text-sm);
    color: rgba(255, 255, 255, 0.8);
    text-align: center;
    max-width: 600px;
}

/* ========================================
   Error & Empty States
   ======================================== */
.drift-error {
    text-align: center;
    padding: var(--drift-space-10);
    color: var(--drift-color-text-muted);
}

.drift-error__title {
    font-size: var(--drift-text-lg);
    margin: 0 0 var(--drift-space-3);
}

.drift-error__message {
    font-size: var(--drift-text-sm);
    margin: 0;
}

/* ========================================
   Responsive Design
   ======================================== */

/* Tablet */
@media (max-width: 900px) {
    .drift-stats__inner {
        grid-template-columns: repeat(2, 1fr);
    }

    .drift-spread {
        grid-template-columns: 1fr;
    }

    .drift-page--right {
        order: -1;
    }
}

/* Mobile */
@media (max-width: 640px) {
    :root {
        --drift-text-3xl: 28px;
        --drift-text-2xl: 22px;
    }

    .drift-container {
        padding: 0 var(--drift-space-4);
    }

    .drift-header {
        padding: var(--drift-space-6) 0 var(--drift-space-4);
    }

    .drift-hero {
        height: 300px;
        margin: var(--drift-space-5) 0;
    }

    .drift-hero__motto {
        font-size: var(--drift-text-base);
    }

    .drift-stats__inner {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--drift-space-3);
    }

    .drift-stat {
        padding: var(--drift-space-4);
    }

    .drift-stat__number {
        font-size: var(--drift-text-2xl);
    }

    .drift-timeline-item:nth-child(odd),
    .drift-timeline-item:nth-child(even) {
        margin: 0 0 var(--drift-space-4);
        width: 100%;
    }

    .drift-timeline-item {
        padding: var(--drift-space-3);
    }

    .drift-timeline-item::before {
        display: none;
    }

    .drift-archive-card {
        grid-template-columns: 1fr;
        gap: var(--drift-space-3);
    }

    .drift-archive-card__number {
        order: -1;
    }

    .drift-reader__container {
        max-height: 95vh;
        margin: var(--drift-space-3);
        border-radius: var(--drift-radius-md);
    }

    .drift-reader__content {
        padding: var(--drift-space-4);
    }

    .drift-page {
        padding: var(--drift-space-4);
    }

    .drift-page__title {
        font-size: var(--drift-text-xl);
    }

    .drift-reader__nav {
        padding: var(--drift-space-3) var(--drift-space-4);
    }

    .drift-hero__hint {
        display: none;
    }
}

/* ========================================
   Reduced Motion
   ======================================== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* ========================================
   Focus Styles (Accessibility)
   ======================================== */
.drift-btn:focus-visible,
.drift-archive-card:focus-visible,
.drift-reader__close:focus-visible,
.drift-lightbox__close:focus-visible {
    outline: 2px solid var(--drift-color-accent);
    outline-offset: 2px;
}

/* ========================================
   Print Styles
   ======================================== */
@media print {
    .drift-loading,
    .drift-hero__canvas,
    .drift-reader,
    .drift-lightbox {
        display: none !important;
    }

    .drift-archive-page {
        background: #fff;
        color: #000;
    }

    .drift-page {
        box-shadow: none;
        page-break-inside: avoid;
    }
}