/* HomeworkMint (homeworkmint.com) — plain CSS, mobile-first */
:root {
  --bg: #f7f8fc; --card: #fff; --text: #1d2433; --muted: #5f6b80; --line: #e3e7ef;
  --brand: #0f9f74; --brand-2: #0b7d5c; --ok: #0f9d58; --warn: #d97706; --err: #c62828;
  --radius: 14px; --shadow: 0 2px 10px rgba(20, 30, 60, .06);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; font: 16px/1.55 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; color: var(--text); background: var(--bg); }
.wrap { max-width: 980px; margin: 0 auto; padding: 0 18px; }
section { padding: 36px 0; }
h1 { font-size: clamp(1.9rem, 6vw, 3rem); line-height: 1.15; margin: 0 0 14px; }
h2 { font-size: 1.6rem; margin: 0 0 16px; display: flex; flex-wrap: wrap; align-items: center; gap: 10px; }
h3 { margin: 6px 0; }
a { color: var(--brand); }
code { background: #eef0f7; padding: 1px 5px; border-radius: 4px; }
.muted { color: var(--muted); } .small { font-size: .88rem; }

/* nav */
.nav { position: sticky; top: 0; z-index: 10; background: rgba(255,255,255,.92); backdrop-filter: blur(8px); border-bottom: 1px solid var(--line); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; gap: 10px; min-height: 58px; flex-wrap: wrap; }
.logo { font-weight: 800; font-size: 1.2rem; text-decoration: none; color: var(--text); display: flex; align-items: center; gap: 8px; }
nav { display: flex; gap: 14px; flex-wrap: wrap; }
nav a { text-decoration: none; color: var(--muted); font-weight: 500; font-size: .95rem; }
nav a:hover { color: var(--brand); }

/* hero */
.hero { background: linear-gradient(135deg, #eef0ff, #f6efff); padding: 64px 0 52px; border-bottom: 1px solid var(--line); }
.accent { background: linear-gradient(90deg, var(--brand), var(--brand-2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.lead { font-size: 1.15rem; max-width: 640px; color: #364052; }
.cta { display: flex; gap: 12px; flex-wrap: wrap; margin: 22px 0 10px; }

/* buttons */
.btn { display: inline-block; border: 1px solid var(--line); background: #fff; color: var(--text); padding: 11px 18px; border-radius: 10px; font: inherit; font-weight: 600; cursor: pointer; text-decoration: none; white-space: nowrap; }
.btn:hover { border-color: var(--brand); }
.btn.primary { background: var(--brand); border-color: var(--brand); color: #fff; }
.btn.primary:hover { background: #4338ca; }
.link { background: none; border: 0; color: var(--brand); cursor: pointer; font: inherit; padding: 0; text-decoration: underline; }

/* cards & grids */
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow); }
.grid3, .grid2 { display: grid; gap: 16px; grid-template-columns: 1fr; }
@media (min-width: 720px) { .grid3 { grid-template-columns: repeat(3, 1fr); } .grid2 { grid-template-columns: repeat(2, 1fr); } }
.num { width: 34px; height: 34px; border-radius: 50%; background: var(--brand); color: #fff; display: grid; place-items: center; font-weight: 700; }

/* tools */
.tabs { display: flex; gap: 6px; overflow-x: auto; margin-bottom: 12px; padding-bottom: 2px; }
.tab { border: 1px solid var(--line); background: #fff; padding: 9px 14px; border-radius: 999px; font: inherit; font-weight: 600; color: var(--muted); cursor: pointer; white-space: nowrap; }
.tab.active { background: var(--brand); border-color: var(--brand); color: #fff; }
.row { display: flex; gap: 10px; flex-wrap: wrap; align-items: flex-end; margin: 8px 0; }
.row label { display: flex; flex-direction: column; font-size: .88rem; color: var(--muted); gap: 4px; }
label { font-weight: 600; }
input, select, textarea { font: inherit; padding: 10px 12px; border: 1px solid #cfd6e4; border-radius: 10px; background: #fff; color: var(--text); min-width: 0; }
input:focus, select:focus, textarea:focus { outline: 2px solid #9fe3c9; border-color: var(--brand); }
#expr-in { flex: 1 1 260px; font-family: ui-monospace, Menlo, Consolas, monospace; }
.row input[type=number] { width: 110px; }
#fa, #fb { width: 130px; }
textarea { width: 100%; resize: vertical; margin-top: 8px; }
.examples { font-size: .88rem; color: var(--muted); display: flex; flex-wrap: wrap; gap: 6px; align-items: center; margin-top: 6px; }
.examples button { border: 1px dashed #c8cee0; background: #fafbff; border-radius: 8px; padding: 4px 8px; font: inherit; font-size: .85rem; cursor: pointer; color: var(--text); }
.out:empty { display: none; }
.out { margin-top: 14px; }
.answer { font-size: 1.35rem; font-weight: 700; background: #eefaf3; border: 1px solid #bfe8d0; color: #0b5d36; padding: 12px 14px; border-radius: 10px; word-break: break-word; }
.steps { margin: 12px 0 0; padding-left: 22px; font-family: ui-monospace, Menlo, Consolas, monospace; font-size: .93rem; }
.steps li { padding: 3px 0; }
.err { background: #fdecec; border: 1px solid #f4c2c2; color: var(--err); padding: 10px 14px; border-radius: 10px; }
.label-row { display: flex; justify-content: space-between; gap: 10px; flex-wrap: wrap; }

.pill { font-size: .75rem; font-weight: 600; padding: 3px 10px; border-radius: 999px; background: #efeafe; color: #5b21b6; }
.pill.ok { background: #e3f6ec; color: var(--ok); }
.pill.warn { background: #fff1db; color: var(--warn); }

/* writing results */
.stats { display: grid; grid-template-columns: repeat(2, 1fr); gap: 8px; }
@media (min-width: 640px) { .stats { grid-template-columns: repeat(6, 1fr); } }
.stat { background: #f5f6fb; border-radius: 10px; padding: 10px; text-align: center; }
.stat b { display: block; font-size: 1.25rem; }
.stat span { font-size: .75rem; color: var(--muted); }
.flesch { margin: 14px 0; }
.bar { height: 10px; background: #eceff6; border-radius: 99px; overflow: hidden; margin: 6px 0; }
.bar span { display: block; height: 100%; background: linear-gradient(90deg, #f59e0b, #10b981); }
.check { border-top: 1px solid var(--line); padding: 10px 0; }
.check h4 { margin: 0; display: flex; gap: 8px; align-items: center; font-size: 1rem; }
.check ul { margin: 6px 0; padding-left: 20px; }
.check small { color: var(--muted); }

/* ad placeholder */
.ad { border: 2px dashed #b9c0d0; background: repeating-linear-gradient(45deg, #fafbfd, #fafbfd 10px, #f2f4f8 10px, #f2f4f8 20px); border-radius: 12px; min-height: 90px; display: flex; flex-direction: column; justify-content: center; align-items: center; text-align: center; padding: 14px; color: var(--muted); gap: 4px; }
.ad strong { text-transform: uppercase; letter-spacing: .08em; font-size: .8rem; }
.ad span { font-size: .85rem; }

/* pricing */
.plan { position: relative; display: flex; flex-direction: column; }
.plan ul { padding-left: 20px; flex: 1; }
.price { font-size: 2.2rem; font-weight: 800; }
.price small { font-size: 1rem; color: var(--muted); font-weight: 500; }
.featured { border: 2px solid var(--brand); }
.badge { position: absolute; top: -12px; right: 16px; background: var(--brand); color: #fff; font-size: .75rem; font-weight: 700; padding: 3px 10px; border-radius: 999px; }

.integrity { background: #fff; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); max-width: none; }
.integrity h2, .integrity p { max-width: 944px; margin-left: auto; margin-right: auto; }
footer { padding: 24px 0 40px; color: var(--muted); font-size: .88rem; text-align: center; }

@media (max-width: 520px) {
  nav { gap: 10px; } nav a { font-size: .85rem; }
  .row > .btn { width: 100%; }
  .row input[type=number], #fa, #fb { width: 100%; }
  .row label { flex: 1 1 30%; }
  .hero { padding: 40px 0 34px; }
}

/* --- v2 additions --- */
.auth-area{margin-left:8px;display:inline-flex;gap:8px;align-items:center}
.ai-box{margin-top:16px}.ai-box hr{border:0;border-top:1px solid var(--line);margin:18px 0}
.drop{border:2px dashed #b9c0d0;border-radius:12px;padding:16px;margin:10px 0;background:#fafbff}
.drop input[type=file]{position:absolute;opacity:0;width:1px;height:1px}
.drop.dragover{border-color:var(--brand);background:#eef0ff}
.preview{max-width:100%;max-height:320px;border-radius:10px;border:1px solid var(--line);margin:10px 0}
.photo-block{border-top:1px solid var(--line);margin-top:18px;padding-top:14px}
.ai-answer{white-space:pre-wrap;background:#eefaf3;border:1px solid #bfe8d0;border-radius:10px;padding:14px}
.notice{background:#fff7e6;border:1px solid #f2d492;padding:12px 14px;border-radius:10px}