/* ========================================
   学生管理系统 — 简约白 · 樱花飘落 · 柔和美
   设计规范：
     色板  → #FAFAFA 底, #FFF 卡片, #FADADD 点缀, #333 文字
     字体  → Inter / SF Pro / PingFang SC, 300-500 weight
     圆角  → 8/12/16px
     间距  → 8/16/24/32/48px
     阴影  → 0 4px 12px rgba(0,0,0,.04)
     动效  → cubic-bezier(.4,0,.2,1), 300ms
   ======================================== */

:root {
    --bg:          #FAFAFA;
    --bg-alt:      #F5F5F5;
    --surface:     #FFFFFF;
    --line:        #EEEEEE;
    --line-strong: #E0E0E0;
    --pink:        #FADADD;
    --pink-deep:   #FAD0D0;
    --pink-hover:  #F5C2C7;
    --pink-tint:   #FFF0F0;
    --text:        #333333;
    --text-mid:    #666666;
    --text-soft:   #999999;
    --ok:          #6BA88A;
    --warn:        #C9A227;
    --danger:      #C97C7C;

    /* 辅助点缀（增加层次，用量克制） */
    --lilac:       #E8DFF5;
    --lilac-deep:  #D9CCEF;
    --mint:        #DFF0E8;
    --cream:       #FDF6EC;
    --sky:         #DFEBF7;

    --r-sm: 8px;
    --r-md: 12px;
    --r-lg: 16px;
    --r-xl: 22px;
    --shadow:       0 4px 12px rgba(0,0,0,.04);
    --shadow-hover: 0 6px 20px rgba(0,0,0,.06);
    --sp-1: 8px; --sp-2: 16px; --sp-3: 24px; --sp-4: 32px; --sp-5: 48px;
    --ease: cubic-bezier(.4,0,.2,1);
    --dur: .3s;
    --font: "Inter", -apple-system, "SF Pro Text", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* { margin:0; padding:0; box-sizing:border-box; }
html { -webkit-font-smoothing: antialiased; }
body {
    font-family: var(--font);
    font-weight: 400;
    background: var(--bg);
    color: var(--text);
    line-height: 1.65;
    min-height: 100vh;
    position: relative;
}

/* 柔和渐变光晕 — 让白底有呼吸感与层次 */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    z-index: 0;
    pointer-events: none;
    background:
        radial-gradient(ellipse 60% 45% at 12% 8%,  rgba(250,218,221,.42) 0%, transparent 62%),
        radial-gradient(ellipse 50% 40% at 88% 12%, rgba(232,223,245,.38) 0%, transparent 60%),
        radial-gradient(ellipse 65% 50% at 78% 88%, rgba(223,235,247,.32) 0%, transparent 62%),
        radial-gradient(ellipse 45% 35% at 20% 92%, rgba(253,246,236,.45) 0%, transparent 60%);
}
a { color: var(--text); text-decoration: none; transition: color var(--dur) var(--ease); }
a:hover { color: var(--pink-hover); }
h1,h2,h3 { font-weight: 500; }

/* 键盘可达性：仅键盘聚焦时显示描边 */
a:focus-visible,
button:focus-visible,
.btn:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
    outline: 2px solid var(--pink-hover);
    outline-offset: 2px;
}

/* --- 樱花画布 --- */
#sakura-canvas {
    position: fixed; inset: 0; width: 100%; height: 100%;
    pointer-events: none; z-index: 1;
    opacity: 0; transition: opacity 1.2s var(--ease);
}
#sakura-canvas.ready { opacity: 1; }

/* --- 导航栏 --- */
.nav-bar {
    position: sticky; top: 0; z-index: 100;
    background: rgba(255,255,255,.68);
    backdrop-filter: saturate(180%) blur(22px);
    -webkit-backdrop-filter: saturate(180%) blur(22px);
    border-bottom: 1px solid rgba(0,0,0,.045);
    box-shadow: 0 1px 12px rgba(0,0,0,.02);
}
.nav-inner {
    max-width: 1180px; margin: 0 auto; padding: 0 var(--sp-3);
    height: 64px; display: flex; align-items: center; justify-content: space-between;
}
.nav-brand { font-size: 17px; font-weight: 300; letter-spacing: .08em; color: var(--text); }
.nav-brand:hover { color: var(--text); }
.nav-links { display: flex; align-items: center; gap: var(--sp-3); }
.nav-links a { font-size: 14px; color: var(--text-mid); position: relative; padding: 6px 2px; }
.nav-links a:hover { color: var(--text); }
.nav-links a::after {
    content: ''; position: absolute; left:0; right:0; bottom:0;
    height: 1.5px; background: var(--pink-deep);
    transform: scaleX(0); transition: transform var(--dur) var(--ease);
}
.nav-links a:hover::after { transform: scaleX(1); }

/* --- 主内容 --- */
.main-content {
    position: relative; z-index: 2;
    max-width: 1180px; margin: 0 auto; padding: var(--sp-5) var(--sp-3);
    min-height: calc(100vh - 64px - 72px);
}

/* --- 卡片（毛玻璃 + 顶部渐变细线） --- */
.card {
    position: relative;
    background: rgba(255,255,255,.72);
    backdrop-filter: blur(18px) saturate(150%);
    -webkit-backdrop-filter: blur(18px) saturate(150%);
    border: 1px solid rgba(255,255,255,.85);
    border-radius: var(--r-xl);
    padding: var(--sp-4);
    margin-bottom: var(--sp-3);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: box-shadow var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.card::before {
    content: '';
    position: absolute; top: 0; left: 0; right: 0; height: 2px;
    background: linear-gradient(90deg, var(--pink-deep), var(--lilac-deep), var(--sky));
    opacity: 0;
    transition: opacity var(--dur) var(--ease);
}
.card:hover { box-shadow: var(--shadow-hover); }
.card:hover::before { opacity: .85; }

.card-title {
    font-size: 15px; font-weight: 500; margin-bottom: var(--sp-3);
    display: flex; align-items: center; gap: 10px; letter-spacing: .02em;
}
.card-title::before {
    content: ''; width: 3px; height: 15px; border-radius: 2px;
    background: linear-gradient(180deg, var(--pink-hover), var(--lilac-deep));
}

/* --- 按钮 --- */
.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 6px;
    padding: 10px 20px; border: 1px solid transparent; border-radius: var(--r-sm);
    font-family: var(--font); font-size: 14px; font-weight: 400;
    color: var(--text); cursor: pointer; transition: all var(--dur) var(--ease); white-space: nowrap;
}
.btn-primary {
    background: linear-gradient(135deg, #FBE0E3, #F6CBD2);
    box-shadow: 0 2px 8px rgba(245,194,199,.35);
}
.btn-primary:hover {
    background: linear-gradient(135deg, #F8D2D7, #F1BCC5);
    color: var(--text);
    box-shadow: 0 4px 14px rgba(245,194,199,.5);
    transform: translateY(-1px);
}
.btn-outline {
    background: rgba(255,255,255,.7);
    backdrop-filter: blur(8px);
    border-color: var(--line-strong);
}
.btn-outline:hover {
    background: var(--pink-tint); border-color: var(--pink-deep); color: var(--text);
    transform: translateY(-1px);
}
.btn-red { background: rgba(255,255,255,.7); border-color: #EBD3D3; color: var(--danger); }
.btn-red:hover { background: #FDF4F4; border-color: var(--danger); }
.btn-sm { padding: 6px 14px; font-size: 13px; border-radius: 6px; }
.btn:disabled { opacity: .4; cursor: not-allowed; }

/* --- 表单 --- */
.form-group { margin-bottom: var(--sp-3); }
.form-group label { display: block; margin-bottom: var(--sp-1); font-size: 13px; color: var(--text-mid); }
.form-control {
    width: 100%; padding: 11px 14px; border: 1px solid var(--line-strong);
    border-radius: var(--r-sm); font-family: var(--font); font-size: 14px;
    color: var(--text); background: var(--surface); transition: all var(--dur) var(--ease);
}
.form-control:focus { outline: none; border-color: var(--pink-deep); box-shadow: 0 0 0 3px rgba(250,208,208,.25); }
.form-control::placeholder { color: var(--text-soft); }
textarea.form-control { resize: vertical; line-height: 1.6; }
.form-row { display: flex; gap: var(--sp-2); flex-wrap: wrap; }
.form-row > .form-group { flex: 1; min-width: 180px; }

/* --- 提示 --- */
.alert { padding: 12px 16px; border-radius: var(--r-sm); margin-bottom: var(--sp-3); font-size: 14px; border: 1px solid; }
.alert-error { background: #FDF4F4; border-color: #F0DADA; color: var(--danger); }
.alert-success { background: #F3F9F5; border-color: #D9EBE0; color: var(--ok); }

/* --- 徽章 --- */
.badge { display:inline-block; padding:3px 10px; border-radius:999px; font-size:12px; background:var(--bg-alt); color:var(--text-mid); }
.badge-pink { background: var(--pink-tint); color: #B5757D; }
.badge-ok   { background: #F3F9F5; color: var(--ok); }
.badge-warn { background: #FCF8EC; color: var(--warn); }
.badge-red  { background: #FDF4F4; color: var(--danger); }

/* --- 页脚 --- */
.footer { position: relative; z-index: 2; text-align: center; padding: var(--sp-3); color: var(--text-soft); font-size: 13px; border-top: 1px solid var(--line); }

/* --- Hero --- */
.hero {
    position: relative; z-index: 2;
    text-align: center;
    padding: 72px var(--sp-3) var(--sp-5);
}
/* 背后柔光晕 */
.hero::before {
    content: '';
    position: absolute;
    top: 10%; left: 50%; transform: translateX(-50%);
    width: min(560px, 88%); height: 260px;
    background: radial-gradient(ellipse at center, rgba(250,218,221,.5) 0%, rgba(232,223,245,.28) 45%, transparent 72%);
    filter: blur(28px);
    z-index: -1;
    pointer-events: none;
}
.hero .eyebrow {
    display: inline-block;
    font-size: 12px; font-weight: 400; letter-spacing: .22em;
    text-transform: uppercase;
    color: var(--text-soft);
    padding: 6px 16px;
    border: 1px solid rgba(250,208,208,.7);
    border-radius: 999px;
    background: rgba(255,255,255,.6);
    backdrop-filter: blur(8px);
    margin-bottom: var(--sp-3);
}
.hero h1 {
    font-size: clamp(30px, 5.5vw, 50px);
    font-weight: 200;
    letter-spacing: .14em;
    line-height: 1.25;
    margin-bottom: var(--sp-2);
}
/* 标题下的细渐变分隔 */
.hero .divider {
    width: 64px; height: 2px; margin: var(--sp-2) auto var(--sp-3);
    border-radius: 2px;
    background: linear-gradient(90deg, transparent, var(--pink-hover), var(--lilac-deep), transparent);
}
.hero .lead {
    font-size: clamp(14px, 2vw, 17px);
    font-weight: 300; color: var(--text-mid);
    margin-bottom: var(--sp-4); letter-spacing: .06em;
}
.hero-actions { display: flex; gap: var(--sp-2); justify-content: center; flex-wrap: wrap; }

/* --- 登录 --- */
.auth-container { position: relative; z-index: 2; display: flex; align-items: center; justify-content: center; min-height: calc(100vh - 64px); padding: var(--sp-3); }
.auth-card { background: var(--surface); border-radius: var(--r-lg); box-shadow: var(--shadow); padding: var(--sp-5) var(--sp-4); width: 100%; max-width: 400px; }
.auth-card h2 { font-size: 22px; font-weight: 300; letter-spacing: .06em; text-align: center; margin-bottom: var(--sp-1); }
.auth-card .auth-sub { text-align: center; font-size: 13px; color: var(--text-soft); margin-bottom: var(--sp-4); }
.auth-foot { text-align: center; margin-top: var(--sp-3); font-size: 13px; color: var(--text-soft); }

/* --- 统计网格 --- */
.stat-grid {
    position: relative; z-index: 2;
    display: grid; grid-template-columns: repeat(auto-fit, minmax(200px,1fr));
    gap: var(--sp-3); margin-bottom: var(--sp-3);
}
.stat-card {
    position: relative;
    background: rgba(255,255,255,.75);
    backdrop-filter: blur(18px) saturate(150%);
    -webkit-backdrop-filter: blur(18px) saturate(150%);
    border: 1px solid rgba(255,255,255,.9);
    border-radius: var(--r-xl);
    padding: var(--sp-3);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: all var(--dur) var(--ease);
}
/* 左上角柔色斑 */
.stat-card::after {
    content: '';
    position: absolute; top: -30px; right: -30px;
    width: 100px; height: 100px; border-radius: 50%;
    background: radial-gradient(circle, rgba(250,218,221,.55), transparent 70%);
    transition: transform var(--dur) var(--ease);
}
.stat-card:nth-child(2)::after { background: radial-gradient(circle, rgba(232,223,245,.55), transparent 70%); }
.stat-card:nth-child(3)::after { background: radial-gradient(circle, rgba(223,235,247,.55), transparent 70%); }
.stat-card:nth-child(4)::after { background: radial-gradient(circle, rgba(223,240,232,.55), transparent 70%); }
.stat-card:hover { box-shadow: var(--shadow-hover); transform: translateY(-3px); }
.stat-card:hover::after { transform: scale(1.35); }
.stat-card .num {
    position: relative;
    font-size: 34px; font-weight: 200; line-height: 1.15; letter-spacing: -.02em;
}
.stat-card .label {
    position: relative;
    font-size: 13px; color: var(--text-soft); margin-top: 6px; letter-spacing: .04em;
}

/* --- 列表项 --- */
.list-item {
    display: block; background: var(--surface); border-radius: var(--r-md); padding: var(--sp-3);
    margin-bottom: var(--sp-2); box-shadow: var(--shadow); transition: all var(--dur) var(--ease);
}
.list-item:hover { box-shadow: var(--shadow-hover); background: var(--pink-tint); color: var(--text); }
.list-item .li-title { font-size: 15px; font-weight: 500; margin-bottom: 4px; }
.list-item .li-meta { font-size: 12px; color: var(--text-soft); display: flex; gap: var(--sp-2); flex-wrap: wrap; }
.list-item .li-desc { font-size: 13px; color: var(--text-mid); margin-top: var(--sp-1); }

/* --- 数据表格 --- */
.data-table { width: 100%; border-collapse: collapse; font-size: 13px; }
.data-table th {
    text-align: left; padding: 10px 12px; font-weight: 500; font-size: 12px;
    color: var(--text-mid); border-bottom: 1px solid var(--line-strong);
    background: var(--bg-alt); text-transform: uppercase; letter-spacing: .03em;
}
.data-table td { padding: 10px 12px; border-bottom: 1px solid var(--line); color: var(--text); }
.data-table tr:hover td { background: var(--pink-tint); }
.actions { display: flex; gap: 6px; flex-wrap: wrap; }

/* --- 空态 --- */
.empty { text-align: center; padding: var(--sp-5); color: var(--text-soft); font-size: 14px; }

/* --- 资料卡（整卡可点，键盘可达） --- */
a.res-card { display: block; color: inherit; }
a.res-card:hover { color: inherit; transform: translateY(-2px); }
a.res-card h3 { transition: color var(--dur) var(--ease); }
a.res-card:hover h3 { color: var(--pink-hover); }
a.res-card:focus-visible {
    outline: 2px solid var(--pink-hover);
    outline-offset: 3px;
}

/* --- 导航品牌（含 logo） --- */
.nav-brand { display: inline-flex; align-items: center; }

/* --- 公告行 --- */
.notice-row {
    position: relative;
    display: flex; align-items: center; justify-content: space-between; gap: var(--sp-2);
    padding: 14px var(--sp-2); margin: 0 calc(var(--sp-2) * -1);
    border-radius: var(--r-md);
    transition: all var(--dur) var(--ease);
}
.notice-row + .notice-row { border-top: 1px solid var(--line); }
.notice-row::before {
    content: '';
    position: absolute; left: 4px; top: 50%; transform: translateY(-50%);
    width: 3px; height: 0; border-radius: 2px;
    background: linear-gradient(180deg, var(--pink-hover), var(--lilac-deep));
    transition: height var(--dur) var(--ease);
}
.notice-row:hover {
    background: linear-gradient(90deg, var(--pink-tint), rgba(255,240,240,.3));
    color: var(--text);
    padding-left: 20px;
}
.notice-row:hover::before { height: 18px; }
.notice-title { font-size: 14px; color: var(--text); }
.notice-row:hover .notice-title { color: var(--text); }
.notice-date { font-size: 12px; color: var(--text-soft); flex-shrink: 0; }

/* --- 活动卡片 --- */
.activity-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: var(--sp-2);
}
.activity-card {
    position: relative;
    background: rgba(255,255,255,.6);
    border: 1px solid rgba(0,0,0,.05);
    border-radius: var(--r-lg);
    padding: var(--sp-3);
    overflow: hidden;
    transition: all var(--dur) var(--ease);
}
.activity-card::before {
    content: '';
    position: absolute; top: 0; left: 0; width: 100%; height: 3px;
    background: linear-gradient(90deg, var(--pink-deep), var(--lilac-deep));
    transform: scaleX(0); transform-origin: left;
    transition: transform var(--dur) var(--ease);
}
.activity-card:hover {
    background: rgba(255,255,255,.92);
    border-color: rgba(250,208,208,.8);
    box-shadow: var(--shadow-hover);
    transform: translateY(-3px);
}
.activity-card:hover::before { transform: scaleX(1); }
.ac-header { display: flex; align-items: flex-start; justify-content: space-between; gap: var(--sp-1); margin-bottom: var(--sp-2); }
.ac-title { font-size: 15px; font-weight: 500; line-height: 1.4; }
.ac-meta { display: flex; flex-direction: column; gap: 5px; font-size: 12px; color: var(--text-soft); }
.ac-footer { margin-top: var(--sp-2); padding-top: var(--sp-2); border-top: 1px solid var(--line); }
.ac-count { font-size: 12px; color: var(--text-mid); }

/* --- 页脚（含校徽） --- */
.site-footer {
    position: relative; z-index: 2;
    margin-top: var(--sp-5);
    padding: var(--sp-4) var(--sp-3) var(--sp-3);
    border-top: 1px solid var(--line);
    background: rgba(255,255,255,.6);
    backdrop-filter: blur(10px);
    text-align: center;
}
.footer-logos {
    display: flex; align-items: center; justify-content: center;
    gap: var(--sp-4); margin-bottom: var(--sp-3); flex-wrap: wrap;
}
.footer-logo {
    object-fit: contain;
    opacity: .82;
    transition: opacity var(--dur) var(--ease);
}
.footer-logo:hover { opacity: 1; }
.footer-text { font-size: 13px; color: var(--text-mid); margin-bottom: var(--sp-2); }
.footer-links {
    display: flex; align-items: center; justify-content: center;
    gap: var(--sp-3); flex-wrap: wrap;
}
.footer-links a { font-size: 12px; color: var(--text-soft); display: inline-flex; align-items: center; }
.footer-links a:hover { color: var(--pink-hover); }

@media (max-width: 640px) {
    .footer-logos { gap: var(--sp-2); }
    .footer-logo { height: 56px !important; width: auto !important; }
    .footer-links { flex-direction: column; gap: var(--sp-1); }
}

/* --- 响应式 --- */
@media (max-width:768px) {
    .hero h1 { font-size: 26px; }
    .main-content { padding: var(--sp-3) var(--sp-2); }
    .card { padding: var(--sp-3); }
    .nav-inner { padding:0 var(--sp-2); height:56px; }
    .nav-links { gap: var(--sp-2); }
    .form-row { flex-direction: column; gap: 0; }
}
@media (prefers-reduced-motion: reduce) {
    * { animation-duration:.01ms!important; transition-duration:.01ms!important; }
    #sakura-canvas { display: none; }
}