:root {
  --ink: #1f2440; --bg: #f6f7fb; --card: #fff; --accent: #5b5bd6; --accent2: #00b3a4;
  --warn: #d64545; --muted: #6b7280; --line: #e4e6ef;
}
* { box-sizing: border-box; }
body { margin: 0; font-family: "Segoe UI", system-ui, sans-serif; color: var(--ink); background: var(--bg); }
a { color: var(--accent); }

.topbar { display: flex; align-items: center; gap: 1.5rem; padding: .8rem 1.4rem;
  background: linear-gradient(90deg, #5b5bd6, #00b3a4); color: #fff; flex-wrap: wrap; }
.topbar a { color: #fff; text-decoration: none; }
.brand { font-weight: 700; font-size: 1.15rem; }
.brand span { font-weight: 400; opacity: .9; }
.topbar nav { display: flex; gap: 1.1rem; align-items: center; margin-left: auto; flex-wrap: wrap; }
.team-chip { background: rgba(255,255,255,.2); padding: .2rem .6rem; border-radius: 999px; font-size: .85rem; }
.nav-cta { background: #fff; color: var(--accent) !important; padding: .35rem .9rem; border-radius: 999px; font-weight: 600; }
.nav-muted { opacity: .8; font-size: .85rem; }

.wrap { max-width: 920px; margin: 0 auto; padding: 1.6rem 1.2rem 3rem; }
.foot { text-align: center; color: var(--muted); padding: 2rem; font-size: .9rem; }

h1 { margin-top: 0; }
.lede { color: var(--muted); font-size: 1.05rem; }
.hint { color: var(--muted); font-size: .85rem; }
.muted { color: var(--muted); }
.error { color: var(--warn); font-weight: 600; }

.btn { background: var(--accent); color: #fff; border: 0; border-radius: 10px;
  padding: .6rem 1.1rem; font-size: 1rem; cursor: pointer; text-decoration: none; display: inline-block; }
.btn.primary { background: var(--accent2); }
.btn.ghost { background: #fff; color: var(--accent); border: 1px solid var(--accent); }
.btn.big { font-size: 1.15rem; padding: .8rem 1.6rem; }
.btn:hover { filter: brightness(1.05); }

.hero { text-align: center; padding: 2rem 0; }
.cards, .tiles { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 1rem; margin-top: 1.5rem; }
.card, .tile, .panel { background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 1.1rem 1.3rem; }
.panel { margin-bottom: 1.4rem; }
.narrow { max-width: 460px; margin: 2rem auto; }

.stack { display: flex; flex-direction: column; gap: .8rem; }
.stack label, .spre-box { display: flex; flex-direction: column; gap: .3rem; font-weight: 600; }
input, textarea, select { font: inherit; padding: .55rem .7rem; border: 1px solid var(--line);
  border-radius: 9px; width: 100%; background: #fff; }
textarea { resize: vertical; }
.row { display: flex; gap: .6rem; align-items: center; flex-wrap: wrap; margin: .8rem 0; }
.row input, .row select { flex: 1; min-width: 160px; }

.spre-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; margin: 1rem 0; }
.spre-box .tag { display: inline-block; background: var(--accent); color: #fff; font-size: .8rem;
  padding: .15rem .55rem; border-radius: 999px; align-self: flex-start; }
.output { white-space: pre-wrap; background: #f0f1fa; border-left: 4px solid var(--accent);
  padding: 1rem; border-radius: 8px; margin-top: 1rem; }
.output.err { background: #fdecec; border-color: var(--warn); }
.makebot { margin-top: 2rem; border-top: 1px dashed var(--line); padding-top: 1rem; }
.botlink { background: #e8fbf8; padding: .8rem 1rem; border-radius: 10px; margin-top: .6rem; }

.chatlog { display: flex; flex-direction: column; gap: .55rem; min-height: 280px; max-height: 55vh;
  overflow-y: auto; padding: 1rem; background: #fff; border: 1px solid var(--line); border-radius: 12px; }
.bubble { padding: .6rem .85rem; border-radius: 14px; max-width: 78%; white-space: pre-wrap; }
.bubble.user { align-self: flex-end; background: var(--accent); color: #fff; }
.bubble.bot { align-self: flex-start; background: #eef0f6; }
.bubble.flagged { background: #fdecec; }

.tile.big img { width: 100%; height: 150px; object-fit: cover; border-radius: 8px; }
.ribbon { display: inline-block; background: #fff4d6; padding: .1rem .5rem; border-radius: 6px; font-size: .8rem; margin: .2rem .2rem 0 0; }
.links a { margin-right: .8rem; }

table.scores { width: 100%; border-collapse: collapse; margin-top: .8rem; }
table.scores th, table.scores td { text-align: left; padding: .45rem .6rem; border-bottom: 1px solid var(--line); }
code.big { font-size: 1.1rem; background: #eef0f6; padding: .15rem .5rem; border-radius: 6px; letter-spacing: 1px; }

.preview-wrap { margin: .8rem 0; }
.preview-box { white-space: pre-wrap; background: #eef0f6; border: 1px dashed var(--accent);
  border-radius: 10px; padding: .8rem 1rem; min-height: 2.5rem; margin: .3rem 0 0; font-size: .95rem; }

.actions { display: flex; gap: .5rem; align-items: center; flex-wrap: wrap; }
.actions form { display: inline; margin: 0; }
.link-danger { background: none; border: 0; color: var(--warn); cursor: pointer; font: inherit; padding: 0; text-decoration: underline; }

/* Printable certificate */
.cert-body { background: #eceefb; display: flex; flex-direction: column; align-items: center; gap: 1rem; padding: 2rem 1rem; }
.cert { background: #fff; width: 100%; max-width: 760px; border: 10px solid var(--accent); border-radius: 16px;
  padding: 2.5rem 2rem; text-align: center; box-shadow: 0 10px 40px rgba(0,0,0,.12); }
.cert-emblem { letter-spacing: 3px; font-weight: 700; color: var(--accent); }
.cert h1 { font-size: 2.2rem; margin: .6rem 0 0; }
.cert-sub { color: var(--accent2); font-weight: 600; letter-spacing: 1px; margin: 0 0 1.5rem; }
.cert-awarded { color: var(--muted); margin: 1rem 0 .2rem; }
.cert-team { font-size: 1.9rem; font-weight: 700; margin: .2rem 0; }
.cert-project { font-size: 1.1rem; margin: .6rem 0; }
.cert-award { font-size: 1.05rem; margin: .2rem 0; }
.cert-date { margin-top: 1.8rem; color: var(--muted); border-top: 1px solid var(--line); display: inline-block; padding-top: .5rem; }
@media print {
  .no-print, .topbar, .foot { display: none !important; }
  .cert-body { background: #fff; padding: 0; }
  .cert { border-color: #333; box-shadow: none; }
}

@media (max-width: 620px) { .spre-grid { grid-template-columns: 1fr; } }