:root {
  --bg: #f4f8f4;
  --panel: #ffffff;
  --panel-2: #eef4ee;
  --border: #d7e3d9;
  --text: #14201a;
  --muted: #4e5e54;
  --accent: #1f9d55;        /* เขียว (สีหลัก) */
  --accent-soft: #e4f5ea;   /* เขียวอ่อน */
  --accent-2: #f57c1f;      /* ส้ม (สีรอง) */
  --accent-2-soft: #fdeede; /* ส้มอ่อน */
  --user: #1f9d55;
  --radius: 14px;
  font-synthesis: none;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: "Segoe UI", "Sarabun", system-ui, -apple-system, sans-serif;
  font-size: 18px;
  line-height: 1.7;
}

.app {
  max-width: 860px;
  margin: 0 auto;
  height: 100dvh;
  display: flex;
  flex-direction: column;
}

/* ---- Topbar ---- */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 18px;
  border-bottom: 1px solid var(--border);
}
.brand { display: flex; align-items: center; gap: 12px; }
.topbar-actions { display: flex; gap: 8px; align-items: center; }
.logo { font-size: 28px; }
.title { font-weight: 700; font-size: 18px; }
.subtitle { color: var(--muted); font-size: 12.5px; }
.reset {
  background: var(--panel-2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 7px 14px;
  cursor: pointer;
  font-size: 13px;
}
.reset:hover { border-color: var(--accent); }

/* ---- Chat ---- */
.chat {
  flex: 1;
  min-height: 0; /* สำคัญ: ให้กล่องแชทเลื่อนในตัวเอง ไม่ดันช่องพิมพ์หลุดจอ */
  overflow-y: auto;
  padding: 22px 18px;
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.welcome { text-align: center; margin: auto 0; color: var(--muted); }
.welcome h1 { color: var(--text); margin: 0 0 8px; font-size: 26px; }
.welcome p { max-width: 520px; margin: 0 auto 22px; }
.suggestions { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; }
.chip {
  background: var(--panel);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 999px;
  padding: 9px 15px;
  font-size: 13.5px;
  cursor: pointer;
}
.chip:hover { border-color: var(--accent); background: var(--accent-soft); }

/* ---- Messages ---- */
.msg { display: flex; flex-direction: column; gap: 5px; max-width: 100%; }
.msg.user { align-items: flex-end; }
.msg .who { font-size: 12px; color: var(--muted); padding: 0 4px; }
.bubble {
  padding: 12px 15px;
  border-radius: var(--radius);
  white-space: pre-wrap;
  word-wrap: break-word;
  max-width: 85%;
}
.msg.user .bubble {
  background: var(--user);
  color: #fff;
  border-bottom-right-radius: 4px;
}
.msg.assistant .bubble {
  background: var(--panel);
  border: 1px solid var(--border);
  border-bottom-left-radius: 4px;
}
.bubble.thinking { color: var(--muted); font-style: italic; }
.bubble strong, .bubble b { font-weight: 700; color: var(--text); }
.bubble hr { border: none; border-top: 1px solid var(--border); margin: 9px 0; }
.mdtable { border-collapse: collapse; width: 100%; margin: 8px 0; font-size: 15px; display: block; overflow-x: auto; }
.mdtable th, .mdtable td { border: 1px solid var(--border); padding: 7px 10px; text-align: left; vertical-align: top; }
.mdtable th { background: var(--accent-soft); font-weight: 700; }
.mdtable tr:nth-child(even) td { background: rgba(31, 157, 85, 0.04); }

.cursor::after {
  content: "▋";
  animation: blink 1s steps(2) infinite;
  color: var(--accent);
}
@keyframes blink { 50% { opacity: 0; } }

/* ---- Composer ---- */
.composer {
  display: flex;
  gap: 10px;
  padding: 14px 18px 18px;
  border-top: 1px solid var(--border);
  align-items: flex-end;
}
#input {
  flex: 1;
  resize: none;
  max-height: 180px;
  background: var(--panel);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 12px 14px;
  font: inherit;
  outline: none;
}
#input:focus { border-color: var(--accent); }
#send {
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 50%;
  width: 44px;
  height: 44px;
  font-size: 18px;
  cursor: pointer;
  flex: none;
}
#send:disabled { opacity: 0.5; cursor: default; }

.error { color: #d64545; font-size: 13.5px; padding: 0 4px; }

/* ---- Chapter 1 form ---- */
a.reset { text-decoration: none; display: inline-flex; align-items: center; }
.ch1form { display: flex; flex-direction: column; gap: 6px; max-width: 720px; margin: 0 auto; width: 100%; }
.ch1form .hint {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 17px;
  color: var(--muted);
  font-size: 15.5px;
  line-height: 1.75;
  margin: 0 0 10px;
}
.ch1form code { background: var(--panel-2); padding: 1px 5px; border-radius: 5px; }
.ch1form label { font-size: 16.5px; font-weight: 600; margin-top: 14px; }
.req { color: #d64545; }
.opt { color: var(--muted); font-weight: normal; font-size: 14px; }
.ch1form input, .ch1form textarea {
  background: var(--panel);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 13px 16px;
  font: inherit;
  outline: none;
  resize: vertical;
}
.ch1form input:focus, .ch1form textarea:focus { border-color: var(--accent); }
.genbtn {
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 10px;
  padding: 14px 22px;
  font: inherit;
  font-size: 17px;
  font-weight: 600;
  cursor: pointer;
  margin-top: 16px;
}
.genbtn:disabled { opacity: 0.5; cursor: default; }

.ch1status {
  max-width: 720px;
  margin: 16px auto 0;
  width: 100%;
  padding: 14px 16px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  font-size: 14px;
}
.ch1status.working { background: var(--accent-soft); border-color: var(--accent); }
.ch1status.error { background: #fdecec; border-color: #e79a9a; color: #c0392b; }

.ch1result { max-width: 720px; margin: 16px auto 0; width: 100%; }
.resultbar {
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
  flex-wrap: wrap;
  background: var(--panel); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 12px 15px; font-size: 13.5px; color: var(--muted);
}
.resultbar .genbtn { margin-top: 0; flex: none; }
.preview {
  background: #fbfaf7;
  color: #1c1c1c;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 30px;
  margin-top: 12px;
  font-family: "TH Sarabun New", "Sarabun", serif;
  line-height: 1.7;
}
.preview .pblock { margin: 0 0 6px; white-space: pre-wrap; }
.preview .pblock.b { font-weight: 700; }
.row2 > div { flex: 1; }

/* ---- user bar (topbar) ---- */
.userbar { display: flex; align-items: center; gap: 10px; font-size: 13px; }
.userbar a { color: var(--text); text-decoration: none; }
.userbar a:hover { color: var(--accent); }
.userbar .credits {
  background: var(--accent-2-soft); border: 1px solid var(--accent-2);
  color: #c15a10; padding: 4px 10px; border-radius: 999px; font-weight: 600;
}

/* ---- ฉากพื้นหลัง glassmorphism ขาว-เขียว (login/register) ---- */
.bg-scene {
  position: fixed; inset: -6%; z-index: 0; overflow: hidden; pointer-events: none;
  background:
    radial-gradient(1200px 800px at 18% 12%, #eafaf1 0%, transparent 60%),
    radial-gradient(1000px 800px at 85% 88%, #dff4e8 0%, transparent 60%),
    linear-gradient(160deg, #f3fbf6 0%, #e6f6ec 100%);
  transition: transform 0.3s ease-out;
}
.ribbons { position: absolute; inset: 0; width: 100%; height: 100%; filter: blur(7px); opacity: 0.5; }
.ribbons path { fill: none; stroke: url(#ilg); stroke-width: 11; stroke-linecap: round; }
.ribbons path:nth-child(2) { opacity: 0.7; }
.ribbons path:nth-child(3) { opacity: 0.45; }
.glow { position: absolute; border-radius: 50%; filter: blur(64px); opacity: 0.5; }
.gA { width: 420px; height: 420px; top: -90px; left: -70px; background: #8fe6b0; animation: floatA 16s ease-in-out infinite; }
.gB { width: 360px; height: 360px; bottom: -80px; right: -60px; background: #5fce8f; animation: floatB 20s ease-in-out infinite; }
.bubble {
  position: absolute; border-radius: 50%;
  background: radial-gradient(circle at 32% 28%,
    rgba(255,255,255,0.9), rgba(180,235,205,0.28) 42%, rgba(31,157,85,0.06) 70%, transparent 72%);
  border: 1px solid rgba(255,255,255,0.6);
  box-shadow: inset 0 0 12px rgba(255,255,255,0.5), 0 6px 16px rgba(31,157,85,0.12);
  animation: bubbleFloat ease-in-out infinite;
}
@keyframes bubbleFloat {
  0%, 100% { transform: translateY(0) scale(1); }
  50% { transform: translateY(-26px) scale(1.05); }
}
@keyframes floatA {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(18px, -22px) scale(1.06); }
}
@keyframes floatB {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(-20px, 16px) scale(1.05); }
}

/* ---- auth pages ---- */
.authwrap { position: relative; z-index: 1; min-height: 100dvh; display: flex; align-items: center; justify-content: center; padding: 20px; }
/* การ์ดกระจกเขียวโปร่งแสง */
.authbox.glass {
  background: rgba(240, 251, 244, 0.45);
  -webkit-backdrop-filter: blur(22px) saturate(170%);
  backdrop-filter: blur(22px) saturate(170%);
  border: 1px solid rgba(255, 255, 255, 0.65);
  border-radius: 26px;
  box-shadow:
    0 0 0 1px rgba(31, 157, 85, 0.12),
    0 24px 70px rgba(31, 157, 85, 0.2),
    0 0 40px rgba(120, 224, 166, 0.25),
    inset 0 1px 0 rgba(255, 255, 255, 0.7);
  transition: transform 0.15s ease-out;
  transform-style: preserve-3d;
  will-change: transform;
}

/* ช่องกรอกทรงแคปซูล + ไอคอน */
.field {
  display: flex; align-items: center; gap: 10px; margin-top: 12px;
  background: rgba(255, 255, 255, 0.5);
  border: 1px solid rgba(31, 157, 85, 0.3);
  border-radius: 999px; padding: 3px 18px;
  transition: border-color 0.15s, box-shadow 0.15s, background 0.15s;
}
.field:focus-within {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(31, 157, 85, 0.16);
  background: rgba(255, 255, 255, 0.72);
}
.field .ficon { width: 18px; height: 18px; color: var(--accent); flex: none; opacity: 0.85; }
.field input {
  flex: 1; background: transparent; border: none; outline: none;
  padding: 12px 0; font: inherit; color: var(--text);
}
.field input::placeholder { color: #7d9585; }

/* ปุ่มเรืองแสง (แคปซูล) */
.loginbtn {
  display: flex; align-items: center; justify-content: center; gap: 10px;
  width: 100%; margin-top: 20px; border: none; cursor: pointer;
  font: inherit; font-weight: 700; font-size: 16px; color: #fff;
  padding: 14px; border-radius: 999px;
  background: linear-gradient(135deg, #5fe094, #1f9d55);
  box-shadow: 0 10px 26px rgba(31, 157, 85, 0.42), 0 0 22px rgba(95, 224, 148, 0.55);
  transition: filter 0.15s, transform 0.1s;
}
.loginbtn:hover { filter: brightness(1.06); }
.loginbtn:active { transform: translateY(1px); }
.loginbtn:disabled { opacity: 0.6; cursor: default; }
.loginbtn svg { width: 20px; height: 20px; }
.authbox {
  width: 100%; max-width: 380px; background: var(--panel);
  border: 1px solid var(--border); border-radius: 16px; padding: 30px 26px;
}
.authlogo { font-size: 18px; font-weight: 700; margin-bottom: 6px; }
.authbox h1 { font-size: 22px; margin: 0 0 18px; }
.authbox form { display: flex; flex-direction: column; gap: 6px; }
.authbox label { font-size: 13px; margin-top: 8px; }
.authbox input {
  background: var(--panel-2); color: var(--text); border: 1px solid var(--border);
  border-radius: 10px; padding: 10px 12px; font: inherit; outline: none;
}
.authbox input:focus { border-color: var(--accent); }
.authbox .genbtn { width: 100%; }
.verifybox {
  border-radius: 10px; padding: 14px 16px; font-size: 14px; line-height: 1.6;
  margin: 0 0 14px; border: 1px solid var(--border); background: var(--panel-2);
}
.verifybox.ok { background: var(--accent-soft); border-color: var(--accent); color: #14663a; }
.verifybox.err { background: #fdecec; border-color: #e79a9a; color: #c0392b; }
.authalt { text-align: center; color: var(--muted); font-size: 13.5px; margin: 16px 0 0; }
.authalt a { color: var(--accent); }

/* ---- account & admin ---- */
.acctwrap { max-width: 760px; margin: 0 auto; width: 100%; display: flex; flex-direction: column; gap: 16px; }
.card { background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius); padding: 18px 20px; }
.card h3 { margin: 0 0 12px; font-size: 16px; }
.statgrid { display: grid; grid-template-columns: repeat(auto-fit, minmax(110px, 1fr)); gap: 12px; }
.stat { background: var(--panel-2); border: 1px solid var(--border); border-radius: 12px; padding: 14px 10px; text-align: center; }
.stat .n { font-size: 24px; font-weight: 800; color: var(--text); line-height: 1.1; }
.stat .n.green { color: var(--accent); }
.stat .n.orange { color: var(--accent-2); }
.stat .l { font-size: 12px; color: var(--muted); margin-top: 3px; }
.muted { color: var(--muted); }
.small { font-size: 15px; }
.balancecard {
  background: linear-gradient(135deg, var(--accent-2-soft), var(--panel));
  border: 1px solid var(--accent-2); border-radius: var(--radius); padding: 22px 24px;
}
.balancelabel { color: var(--muted); font-size: 14px; }
.balancebig { font-size: 34px; font-weight: 800; margin-top: 4px; color: #c15a10; }
.balancebig small { font-size: 14px; font-weight: 400; color: var(--muted); }
.listrow {
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
  padding: 9px 0; border-bottom: 1px solid var(--border);
}
.listrow:last-child { border-bottom: none; }
.minibtn { border: none; border-radius: 8px; padding: 6px 12px; cursor: pointer; font: inherit; font-size: 13px; color: #fff; }
.minibtn.ok { background: var(--accent); }
.minibtn.no { background: #d9534f; margin-inline-start: 6px; }
.minibtn:disabled { opacity: 0.5; }
.miniinput {
  width: 90px; background: var(--panel-2); color: var(--text); border: 1px solid var(--border);
  border-radius: 8px; padding: 6px 8px; font: inherit; margin-inline-end: 6px;
}