/* style.css —— 论文批改系统全局样式(浅色/深色自适应) */

:root {
  color-scheme: light dark;

  --bg: #f6f6f4;
  --surface: #ffffff;
  --surface-2: #fbfbfa;
  --ink: #1f2328;
  --ink-soft: #4b5563;
  --muted: #6b7280;
  --line: #e3e4e8;
  --line-strong: #cfd1d7;
  --accent: #2563eb;
  --accent-soft: #e8effd;
  --ok: #15803d;
  --ok-soft: #e7f5ec;
  --warn: #b45309;
  --warn-soft: #fdf3e3;
  --danger: #b42318;
  --danger-soft: #fdeceb;
  --mark: #fff2a8;

  --radius: 10px;
  --radius-sm: 6px;
  --shadow: 0 1px 2px rgba(16, 24, 40, .05), 0 1px 3px rgba(16, 24, 40, .06);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #15171b;
    --surface: #1d2025;
    --surface-2: #22262c;
    --ink: #e7e9ec;
    --ink-soft: #b9bec6;
    --muted: #8b929c;
    --line: #2c3138;
    --line-strong: #3a4048;
    --accent: #6ea0ff;
    --accent-soft: #1e2a44;
    --ok: #6ee7a0;
    --ok-soft: #16301f;
    --warn: #f0b264;
    --warn-soft: #33260f;
    --danger: #ff8b80;
    --danger-soft: #3a1c19;
    --mark: #6b5c14;
    --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 1px 3px rgba(0, 0, 0, .35);
  }
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: system-ui, -apple-system, "PingFang SC", "Hiragino Sans GB",
               "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  font-size: 15px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 { margin: 0; font-weight: 600; line-height: 1.35; }
h1 { font-size: 1.35rem; }
h2 { font-size: 1.1rem; }
h3 { font-size: 1rem; }
p { margin: 0; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ---------------------------------------------------------------- 布局 */

.app-shell { min-height: 100vh; display: flex; flex-direction: column; }

.topbar {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: .7rem 1.4rem;
  background: var(--surface);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 20;
}
.topbar .brand { font-weight: 650; letter-spacing: .2px; }
.topbar .brand small { color: var(--muted); font-weight: 400; margin-left: .45rem; font-size: .8rem; }
.topbar .spacer { flex: 1; }
.topbar .who { color: var(--muted); font-size: .85rem; }

.page {
  flex: 1;
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  padding: 1.6rem 1.4rem 3rem;
}
.page.narrow { max-width: 760px; }

/* ---------------------------------------------------------------- 组件 */

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.1rem 1.2rem;
}
.card + .card { margin-top: 1rem; }
.card-head {
  display: flex; align-items: center; gap: .75rem;
  margin-bottom: .85rem;
}
.card-head .spacer { flex: 1; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .35rem;
  padding: .42rem .85rem;
  font: inherit; font-size: .875rem;
  color: var(--ink);
  background: var(--surface);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  cursor: pointer;
  white-space: nowrap;
  transition: background .12s ease, border-color .12s ease;
}
.btn:hover:not(:disabled) { background: var(--surface-2); border-color: var(--muted); }
.btn:disabled { opacity: .5; cursor: not-allowed; }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.primary:hover:not(:disabled) { filter: brightness(1.08); background: var(--accent); }
.btn.ghost { border-color: transparent; background: transparent; color: var(--muted); }
.btn.ghost:hover:not(:disabled) { background: var(--surface-2); color: var(--ink); }
.btn.danger { color: var(--danger); border-color: var(--danger); background: transparent; }
.btn.danger:hover:not(:disabled) { background: var(--danger-soft); }
.btn.sm { padding: .22rem .55rem; font-size: .8rem; }

.input, .textarea, .select {
  width: 100%;
  padding: .5rem .7rem;
  font: inherit;
  color: var(--ink);
  background: var(--surface);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
}
.input:focus, .textarea:focus, .select:focus {
  outline: 2px solid var(--accent);
  outline-offset: -1px;
  border-color: var(--accent);
}
.textarea { resize: vertical; min-height: 220px; line-height: 1.8; }

.field { margin-bottom: .9rem; }
.field > label { display: block; font-size: .82rem; color: var(--muted); margin-bottom: .3rem; }

.tag {
  display: inline-flex; align-items: center; gap: .3rem;
  padding: .1rem .5rem;
  font-size: .76rem;
  border-radius: 999px;
  border: 1px solid var(--line-strong);
  color: var(--ink-soft);
  background: var(--surface-2);
  white-space: nowrap;
}
.tag.accent { color: var(--accent); border-color: var(--accent); background: var(--accent-soft); }
.tag.ok { color: var(--ok); border-color: var(--ok); background: var(--ok-soft); }
.tag.warn { color: var(--warn); border-color: var(--warn); background: var(--warn-soft); }
.tag.danger { color: var(--danger); border-color: var(--danger); background: var(--danger-soft); }

.muted { color: var(--muted); }
.small { font-size: .82rem; }
.mono { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; }
.row { display: flex; align-items: center; gap: .6rem; flex-wrap: wrap; }
.stack > * + * { margin-top: .75rem; }

.banner {
  padding: .6rem .8rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line-strong);
  font-size: .875rem;
}
.banner.error { color: var(--danger); background: var(--danger-soft); border-color: var(--danger); }
.banner.info { color: var(--accent); background: var(--accent-soft); border-color: var(--accent); }
.banner.ok { color: var(--ok); background: var(--ok-soft); border-color: var(--ok); }

.empty {
  padding: 2.6rem 1rem;
  text-align: center;
  color: var(--muted);
  border: 1px dashed var(--line-strong);
  border-radius: var(--radius);
  font-size: .9rem;
}

table.list { width: 100%; border-collapse: collapse; }
table.list th, table.list td {
  text-align: left; padding: .6rem .5rem;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}
table.list th { font-size: .8rem; color: var(--muted); font-weight: 500; }
table.list tbody tr:hover { background: var(--surface-2); }
table.list td.actions { white-space: nowrap; text-align: right; }

/* ---------------------------------------------------------------- 论文正文与批注 */

/* 两栏:左侧正文,右侧批注侧边栏 —— 视觉上明确「原文」与「批改」是分离的 */
.review-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 340px;
  gap: 1.1rem;
  align-items: start;
}
@media (max-width: 900px) {
  .review-layout { grid-template-columns: minmax(0, 1fr); }
}

.paper-meta {
  display: flex; align-items: center; gap: .6rem; flex-wrap: wrap;
  padding-bottom: .8rem; margin-bottom: .9rem;
  border-bottom: 1px solid var(--line);
}

/* 正文段落。label 明确标出这是「学生原文」,不可被批注改写 */
.paragraph {
  position: relative;
  padding: .55rem .75rem;
  border-left: 3px solid transparent;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}
.paragraph + .paragraph { margin-top: .4rem; }
.paragraph:hover { background: var(--surface-2); }
.paragraph.has-annotation { border-left-color: var(--accent); background: var(--accent-soft); }
/* 教师正在把批注挂到这一段上(尚未提交) */
.paragraph.is-target {
  border-left-color: var(--warn);
  background: var(--warn-soft);
  outline: 1px dashed var(--warn);
  outline-offset: -1px;
}
.paragraph .para-index {
  position: absolute; left: -2.2rem; top: .6rem;
  font-size: .72rem; color: var(--muted);
  font-variant-numeric: tabular-nums;
  user-select: none;
}
.paragraph .para-text { white-space: pre-wrap; word-break: break-word; }

.readonly-note {
  display: flex; align-items: center; gap: .4rem;
  font-size: .78rem; color: var(--muted);
  margin-bottom: .5rem;
}

.side { position: sticky; top: 4.2rem; }
.annotation {
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius-sm);
  background: var(--surface);
  padding: .6rem .7rem;
}
.annotation + .annotation { margin-top: .6rem; }
.annotation.is-resolved { border-left-color: var(--ok); opacity: .78; }
.annotation.is-ignored { border-left-color: var(--muted); opacity: .6; }
.annotation .head { display: flex; align-items: center; gap: .45rem; margin-bottom: .3rem; }
.annotation .head .spacer { flex: 1; }
.annotation .quote {
  font-size: .8rem; color: var(--muted);
  border-left: 2px solid var(--line-strong);
  padding-left: .5rem; margin: .35rem 0;
  white-space: pre-wrap; word-break: break-word;
}
.annotation .comment { white-space: pre-wrap; word-break: break-word; }

.diff-view { display: grid; gap: .5rem; }
.diff-block {
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: .5rem .7rem;
  font-size: .9rem;
  white-space: pre-wrap;
  word-break: break-word;
}
.diff-block.added { background: var(--ok-soft); border-color: var(--ok); }
.diff-block.removed { background: var(--danger-soft); border-color: var(--danger); }
.diff-block.same { color: var(--muted); }

.timeline { border-left: 2px solid var(--line); padding-left: 1rem; }
.timeline .item { position: relative; padding-bottom: 1rem; }
.timeline .item::before {
  content: ''; position: absolute; left: -1.42rem; top: .5rem;
  width: 9px; height: 9px; border-radius: 50%;
  background: var(--surface); border: 2px solid var(--line-strong);
}
.timeline .item.current::before { background: var(--accent); border-color: var(--accent); }

/* ---------------------------------------------------------------- 登录页 */

.login-wrap {
  min-height: 100vh;
  display: flex; align-items: center; justify-content: center;
  padding: 2rem 1rem;
}
.login-box { width: 100%; max-width: 420px; }
.login-box .brandline { text-align: center; margin-bottom: 1.2rem; }
.login-box .brandline h1 { font-size: 1.5rem; }
.login-box .brandline p { color: var(--muted); font-size: .88rem; margin-top: .3rem; }

.demo-accounts {
  margin-top: 1rem;
  border-top: 1px dashed var(--line-strong);
  padding-top: .8rem;
}
.demo-accounts .chips { display: flex; flex-wrap: wrap; gap: .4rem; margin-top: .5rem; }