/* ===================================================================
   GPA Calculator — styles
   Base/layout · Extended features (semester · charts · predict) · Ad popup
   =================================================================== */

/* ============ Base & layout ============ */
:root {
  --paper: #f1e9da;
  --paper-2: #e8dec9;
  --card: #fbf6ec;
  --ink: #221f1a;
  --ink-soft: #5b5246;
  --ink-faint: #8a7f6e;
  --line: rgba(34, 31, 26, 0.16);
  --line-strong: rgba(34, 31, 26, 0.4);
  --accent: #b8341f; /* registrar red / con dấu */
  --accent-deep: #8c2415;
  --gold: #a8782a;
  --teal: #1f5b53;
  --shadow: 18px 22px 0 rgba(34, 31, 26, 0.08);
  --grade-a: #2c6b41;
  --grade-b: #284a78;
  --grade-c: #8f6618;
  --grade-d: #a8501c;
  --grade-f: #a32418;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
html { scroll-behavior: smooth; }

body {
  font-family: "Be Vietnam Pro", system-ui, sans-serif;
  color: var(--ink);
  line-height: 1.6;
  min-height: 100dvh;
  padding: 36px 22px 80px;
  background-color: var(--paper);
  background-image:
    linear-gradient(rgba(34, 31, 26, 0.045) 1px, transparent 1px),
    radial-gradient(circle at 18% 12%, rgba(184, 52, 31, 0.06), transparent 40%),
    radial-gradient(circle at 85% 8%, rgba(168, 120, 42, 0.08), transparent 45%);
  background-size: 100% 30px, 100% 100%, 100% 100%;
  -webkit-font-smoothing: antialiased;
}
/* paper grain */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  opacity: 0.5;
  mix-blend-mode: multiply;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.04'/%3E%3C/svg%3E");
}

.sheet {
  position: relative;
  z-index: 1;
  max-width: 1080px;
  margin: 0 auto;
  background: var(--card);
  border: 1.5px solid var(--ink);
  box-shadow: var(--shadow);
}

/* ---------------- Masthead ---------------- */
.masthead {
  padding: 34px 44px 30px;
  border-bottom: 3px double var(--ink);
  position: relative;
}
.masthead .eyebrow {
  display: flex;
  align-items: center;
  gap: 14px;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.32em;
  text-transform: uppercase;
  color: var(--ink-soft);
}
.masthead .eyebrow::before,
.masthead .eyebrow::after {
  content: "";
  height: 1px;
  background: var(--line-strong);
}
.masthead .eyebrow::after { flex: 1; }
.masthead .eyebrow .star { color: var(--accent); }

.masthead h1 {
  font-family: "Fraunces", serif;
  font-optical-sizing: auto;
  font-weight: 600;
  font-size: clamp(2.6rem, 7vw, 4.6rem);
  line-height: 0.96;
  letter-spacing: -0.02em;
  margin: 16px 0 14px;
}
.masthead h1 em {
  font-style: italic;
  font-weight: 500;
  color: var(--accent);
}
.masthead .lead {
  max-width: 560px;
  font-size: 1.02rem;
  color: var(--ink-soft);
}
.masthead .filed {
  position: absolute;
  top: 30px;
  right: 44px;
  text-align: right;
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-faint);
  line-height: 1.7;
}
.stamp {
  display: inline-block;
  margin-top: 6px;
  padding: 5px 12px;
  font-family: "Fraunces", serif;
  font-style: italic;
  font-size: 0.82rem;
  letter-spacing: 0.05em;
  color: var(--accent);
  border: 2px solid var(--accent);
  border-radius: 4px;
  transform: rotate(-5deg);
  opacity: 0.85;
}

.body-pad { padding: 36px 44px 46px; }

/* ---------------- Toolbar ---------------- */
.toolbar {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 18px;
}
.toolbar h2,
.results h2 {
  font-family: "Fraunces", serif;
  font-weight: 600;
  font-size: 1.6rem;
  letter-spacing: -0.01em;
}
.toolbar h2 .count {
  font-family: "Be Vietnam Pro", sans-serif;
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-left: 10px;
  vertical-align: middle;
}

#addSubjectBtn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 12px 22px;
  background: var(--ink);
  color: var(--paper);
  border: 1.5px solid var(--ink);
  font-family: inherit;
  font-size: 0.92rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  cursor: pointer;
  border-radius: 2px;
  box-shadow: 4px 4px 0 var(--accent);
  transition: transform 0.16s ease, box-shadow 0.16s ease, background 0.16s ease;
}
#addSubjectBtn .plus {
  font-family: "Fraunces", serif;
  font-size: 1.25em;
  line-height: 0;
}
#addSubjectBtn:hover {
  transform: translate(-2px, -2px);
  box-shadow: 7px 7px 0 var(--accent);
  background: var(--accent-deep);
  border-color: var(--accent-deep);
}
#addSubjectBtn:active {
  transform: translate(2px, 2px);
  box-shadow: 1px 1px 0 var(--accent);
}

/* ---------------- Ledger table ---------------- */
.table-container {
  width: 100%;
  overflow-x: auto;
  border-top: 2px solid var(--ink);
  border-bottom: 2px solid var(--ink);
}
table {
  width: 100%;
  border-collapse: collapse;
  min-width: 740px;
  font-variant-numeric: tabular-nums;
}
thead th {
  text-align: left;
  padding: 12px 16px;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-soft);
  border-bottom: 1.5px solid var(--ink);
  white-space: nowrap;
}
thead th:nth-child(n + 2):nth-child(-n + 6) { text-align: center; }
tbody td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--line);
  color: var(--ink);
  font-size: 0.95rem;
}
tbody td:nth-child(n + 2):nth-child(-n + 6) {
  text-align: center;
  font-feature-settings: "tnum";
}
tbody tr:last-child td { border-bottom: none; }
tbody td:first-child {
  font-family: "Fraunces", serif;
  font-weight: 500;
  font-size: 1.02rem;
}
tbody tr { transition: background 0.14s ease; }
tbody tr:hover { background: rgba(184, 52, 31, 0.05); }
.score10 { font-weight: 700; }

/* grade token */
.grade {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 40px;
  height: 28px;
  padding: 0 8px;
  font-family: "Fraunces", serif;
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--g, var(--ink));
  border: 1.5px solid var(--g, var(--ink));
  border-radius: 3px;
  background: color-mix(in srgb, var(--g) 9%, transparent);
}
.grade-a { --g: var(--grade-a); }
.grade-b { --g: var(--grade-b); }
.grade-c { --g: var(--grade-c); }
.grade-d { --g: var(--grade-d); }
.grade-f { --g: var(--grade-f); }

td.actions { white-space: nowrap; text-align: right; }
td.actions button {
  margin-left: 8px;
  padding: 7px 12px;
  font-family: inherit;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  cursor: pointer;
  background: transparent;
  border: 1.5px solid var(--line-strong);
  border-radius: 2px;
  color: var(--ink-soft);
  transition: all 0.14s ease;
}
.edit-btn:hover { border-color: var(--teal); color: var(--teal); }
.delete-btn:hover { border-color: var(--accent); color: var(--accent); }
.empty-row td {
  text-align: center !important;
  padding: 48px 20px;
  color: var(--ink-faint);
  font-family: "Fraunces", serif;
  font-style: italic;
  font-size: 1.1rem;
}

/* ---------------- Results ---------------- */
.results {
  margin-top: 48px;
  padding-top: 30px;
  border-top: 3px double var(--ink);
}
.results h2 { margin-bottom: 24px; }
.transcript {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 40px;
  align-items: center;
}

/* GPA gauge / seal */
.seal { position: relative; width: 240px; height: 240px; }
.seal svg { width: 100%; height: 100%; transform: rotate(-90deg); }
.gauge-track {
  fill: none;
  stroke: var(--paper-2);
  stroke-width: 13;
}
.gauge-fill {
  fill: none;
  stroke: var(--accent);
  stroke-width: 13;
  stroke-linecap: round;
  transition: stroke-dashoffset 1.3s cubic-bezier(0.16, 1, 0.3, 1);
}
.seal-center {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
}
.seal-center .cap {
  font-size: 0.66rem;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--ink-faint);
}
.seal-center #gpa4 {
  font-family: "Fraunces", serif;
  font-weight: 600;
  font-size: 3.6rem;
  line-height: 1;
  margin: 2px 0;
  letter-spacing: -0.02em;
}
.seal-center .scale {
  font-family: "Fraunces", serif;
  font-style: italic;
  font-size: 0.95rem;
  color: var(--ink-soft);
}
.seal .ring-deco {
  position: absolute;
  inset: 28px;
  border: 1px dashed var(--line-strong);
  border-radius: 50%;
  pointer-events: none;
}

.ledger-lines { display: flex; flex-direction: column; }
.ledger-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding: 16px 4px;
  border-bottom: 1px solid var(--line);
}
.ledger-row:first-child { padding-top: 0; }
.ledger-row .k {
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-soft);
  white-space: nowrap;
}
.ledger-row .dots {
  flex: 1;
  border-bottom: 1px dotted var(--line-strong);
  transform: translateY(-4px);
}
.ledger-row .v {
  font-family: "Fraunces", serif;
  font-weight: 600;
  font-size: 1.7rem;
  line-height: 1;
  font-variant-numeric: tabular-nums;
}
.ledger-row .v.rank { color: var(--accent); font-style: italic; }

.colophon {
  margin-top: 34px;
  padding: 20px 24px;
  background: var(--paper);
  border: 1px solid var(--line);
  border-left: 4px solid var(--accent);
  font-size: 0.9rem;
  color: var(--ink-soft);
  line-height: 1.75;
}
.colophon a {
  color: var(--accent-deep);
  font-weight: 600;
  text-decoration: none;
  border-bottom: 1px solid currentColor;
}
.colophon a:hover { color: var(--accent); }

/* ---------------- Modal ---------------- */
.modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 1000;
  overflow: auto;
  background: rgba(34, 31, 26, 0.4);
  backdrop-filter: blur(3px);
  animation: fade 0.2s ease-out;
}
@keyframes fade { from { opacity: 0; } to { opacity: 1; } }
.modal-content {
  position: relative;
  background: var(--card);
  margin: 7vh auto;
  padding: 38px 36px 34px;
  width: 92%;
  max-width: 520px;
  border: 1.5px solid var(--ink);
  box-shadow: 14px 16px 0 rgba(34, 31, 26, 0.15);
  animation: pop 0.32s cubic-bezier(0.16, 1, 0.3, 1);
}
@keyframes pop {
  from { transform: translateY(18px) rotate(-0.4deg); opacity: 0; }
  to { transform: translateY(0) rotate(0); opacity: 1; }
}
#modalTitle {
  font-family: "Fraunces", serif;
  font-weight: 600;
  font-size: 1.7rem;
  margin-bottom: 6px;
  padding-right: 30px;
}
.modal-content .sub {
  font-size: 0.8rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-faint);
  border-bottom: 1px solid var(--line);
  padding-bottom: 18px;
  margin-bottom: 22px;
}
.close-button {
  position: absolute;
  top: 26px;
  right: 30px;
  font-family: "Fraunces", serif;
  font-size: 30px;
  line-height: 1;
  color: var(--ink-faint);
  cursor: pointer;
  transition: color 0.15s ease, transform 0.15s ease;
}
.close-button:hover { color: var(--accent); transform: rotate(90deg); }

#subjectForm .grid2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
#subjectForm div { margin-bottom: 16px; }
#subjectForm .grid2 > div { margin-bottom: 0; }
#subjectForm label {
  display: block;
  margin-bottom: 6px;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--ink-soft);
}
#subjectForm input[type="text"],
#subjectForm input[type="number"],
#subjectForm select {
  width: 100%;
  padding: 12px 14px;
  background: var(--paper);
  border: none;
  border-bottom: 1.5px solid var(--line-strong);
  font-family: inherit;
  font-size: 1rem;
  color: var(--ink);
  transition: border-color 0.15s ease, background 0.15s ease;
}
#subjectForm select { cursor: pointer; }
#subjectForm input::placeholder { color: var(--ink-faint); }
#subjectForm input:focus,
#subjectForm select:focus {
  outline: none;
  background: #fff;
  border-bottom-color: var(--accent);
}
#subjectForm input[type="number"] { appearance: textfield; }
#subjectForm input[type="number"]::-webkit-outer-spin-button,
#subjectForm input[type="number"]::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}
.form-actions { display: flex; gap: 12px; margin-top: 28px; }
#subjectForm button {
  flex: 1;
  padding: 13px 18px;
  font-family: inherit;
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  cursor: pointer;
  border-radius: 2px;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}
#subjectForm button[type="submit"] {
  background: var(--accent);
  color: var(--paper);
  border: 1.5px solid var(--accent);
  box-shadow: 4px 4px 0 var(--ink);
}
#subjectForm button[type="submit"]:hover {
  transform: translate(-2px, -2px);
  box-shadow: 6px 6px 0 var(--ink);
  background: var(--accent-deep);
}
#subjectForm button[type="button"] {
  background: transparent;
  color: var(--ink-soft);
  border: 1.5px solid var(--line-strong);
}
#subjectForm button[type="button"]:hover { border-color: var(--ink); color: var(--ink); }

/* ---------------- Entrance animation ---------------- */
.reveal {
  opacity: 0;
  transform: translateY(16px);
  animation: rise 0.7s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
@keyframes rise { to { opacity: 1; transform: translateY(0); } }

@media (prefers-reduced-motion: reduce) {
  *, *::before { animation: none !important; transition: none !important; }
  .reveal { opacity: 1; transform: none; }
}

/* ---------------- Responsive ---------------- */
@media (max-width: 820px) {
  .masthead, .body-pad { padding-left: 26px; padding-right: 26px; }
  .masthead .filed { display: none; }
  .transcript { grid-template-columns: 1fr; justify-items: center; gap: 30px; }
  .ledger-lines { width: 100%; }
  .toolbar { flex-direction: column; align-items: stretch; }
  #addSubjectBtn { justify-content: center; }
}
@media (max-width: 560px) {
  body { padding: 18px 12px 50px; }
  .masthead, .body-pad { padding-left: 18px; padding-right: 18px; }
  .modal-content { padding: 28px 22px; }
  #subjectForm .grid2 { grid-template-columns: 1fr; gap: 0; }
  #subjectForm .grid2 > div { margin-bottom: 16px; }
}

/* ============ Extended features (semester · charts · predict · export) ============ */
/* secondary action toolbar */
.data-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: -2px 0 22px;
}
.btn-ghost {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 9px 15px;
  background: var(--paper);
  color: var(--ink-soft);
  border: 1.5px solid var(--line-strong);
  border-radius: 2px;
  font-family: inherit;
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: transform 0.14s ease, box-shadow 0.14s ease,
    border-color 0.14s ease, color 0.14s ease, background 0.14s ease;
}
.btn-ghost:hover {
  color: var(--ink);
  border-color: var(--ink);
  transform: translate(-1px, -1px);
  box-shadow: 3px 3px 0 var(--accent);
}
.btn-ghost:active { transform: translate(1px, 1px); box-shadow: none; }
.btn-ghost .ic { font-size: 1.05em; line-height: 0; }

/* semester group header inside the ledger table */
tr.sem-head td {
  background: var(--paper-2);
  border-top: 2px solid var(--ink) !important;
  border-bottom: 1.5px solid var(--ink) !important;
  padding: 10px 16px !important;
  text-align: left !important;
}
tr.sem-head .sem-head-inner {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  flex-wrap: wrap;
}
tr.sem-head .sem-name {
  font-family: "Fraunces", serif;
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: -0.01em;
}
tr.sem-head .sem-meta {
  font-size: 0.74rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--ink-soft);
}
tr.sem-head .sem-meta b { color: var(--accent-deep); font-weight: 700; }
tr.sem-head .sem-meta { margin-left: auto; }
tr.sem-head .sem-actions {
  display: flex;
  gap: 8px;
  flex-shrink: 0;
}
tr.sem-head .sem-btn {
  padding: 5px 11px;
  font-family: inherit;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  cursor: pointer;
  background: transparent;
  border: 1.5px solid var(--line-strong);
  border-radius: 2px;
  color: var(--ink-soft);
  transition: all 0.14s ease;
}
tr.sem-head .sem-btn.sem-add:hover { border-color: var(--teal); color: var(--teal); }
tr.sem-head .sem-btn.sem-del:hover { border-color: var(--accent); color: var(--accent); }

td.sem-empty {
  text-align: center !important;
  padding: 22px 16px !important;
  color: var(--ink-faint);
  font-family: "Fraunces", serif;
  font-style: italic;
  font-size: 0.98rem;
}
.sem-empty-add {
  font-family: "Be Vietnam Pro", sans-serif;
  font-style: normal;
  font-size: 0.84rem;
  font-weight: 600;
  color: var(--accent-deep);
  background: none;
  border: none;
  border-bottom: 1px solid currentColor;
  cursor: pointer;
  padding: 0;
}
.sem-empty-add:hover { color: var(--accent); }

/* toolbar: group the two "add" buttons */
.toolbar-actions {
  display: flex;
  gap: 10px;
  align-items: center;
  flex-wrap: wrap;
}
#addSemesterBtn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 20px;
  background: var(--paper);
  color: var(--ink);
  border: 1.5px solid var(--ink);
  font-family: inherit;
  font-size: 0.92rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  cursor: pointer;
  border-radius: 2px;
  box-shadow: 4px 4px 0 var(--ink-soft);
  transition: transform 0.16s ease, box-shadow 0.16s ease, background 0.16s ease;
}
#addSemesterBtn .plus { font-family: "Fraunces", serif; font-size: 1.2em; line-height: 0; }
#addSemesterBtn:hover {
  transform: translate(-2px, -2px);
  box-shadow: 7px 7px 0 var(--ink-soft);
  background: var(--paper-2);
}
#addSemesterBtn:active {
  transform: translate(2px, 2px);
  box-shadow: 1px 1px 0 var(--ink-soft);
}

/* analytics + tools shared section chrome */
.analytics,
.tools {
  margin-top: 48px;
  padding-top: 30px;
  border-top: 3px double var(--ink);
}
.analytics h2,
.tools h2 {
  font-family: "Fraunces", serif;
  font-weight: 600;
  font-size: 1.6rem;
  letter-spacing: -0.01em;
  margin-bottom: 6px;
}
.section-note {
  font-size: 0.92rem;
  color: var(--ink-soft);
  margin-bottom: 24px;
  max-width: 620px;
}

.sem-cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(168px, 1fr));
  gap: 14px;
  margin-bottom: 34px;
}
.sem-card {
  padding: 15px 18px;
  background: var(--paper);
  border: 1px solid var(--line);
  border-left: 4px solid var(--accent);
}
.sem-card.cumulative { border-left-color: var(--teal); background: var(--paper-2); }
.sem-card .lbl {
  font-size: 0.7rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-faint);
}
.sem-card .big {
  font-family: "Fraunces", serif;
  font-weight: 600;
  font-size: 1.95rem;
  line-height: 1.1;
  margin: 4px 0 2px;
  font-variant-numeric: tabular-nums;
}
.sem-card .sub { font-size: 0.78rem; color: var(--ink-soft); }

.charts {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 26px;
}
.chart-box {
  padding: 20px 22px;
  background: var(--paper);
  border: 1px solid var(--line);
}
.chart-box h3 {
  font-family: "Fraunces", serif;
  font-weight: 600;
  font-size: 1.05rem;
  margin-bottom: 12px;
}
.chart-box svg { width: 100%; height: auto; display: block; }
.chart-empty {
  color: var(--ink-faint);
  font-style: italic;
  font-family: "Fraunces", serif;
  padding: 26px 0;
  text-align: center;
}

/* prediction tools */
.tool-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 26px;
}
.tool-card {
  padding: 24px 24px 26px;
  background: var(--paper);
  border: 1.5px solid var(--ink);
  box-shadow: 7px 8px 0 rgba(34, 31, 26, 0.07);
}
.tool-card h3 {
  font-family: "Fraunces", serif;
  font-weight: 600;
  font-size: 1.22rem;
  margin-bottom: 4px;
}
.tool-card .desc {
  font-size: 0.85rem;
  color: var(--ink-soft);
  margin-bottom: 18px;
  line-height: 1.55;
}
.tool-field { margin-bottom: 14px; }
.tool-field label {
  display: block;
  margin-bottom: 6px;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--ink-soft);
}
.tool-card input,
.tool-card select {
  width: 100%;
  padding: 11px 13px;
  background: var(--card);
  border: none;
  border-bottom: 1.5px solid var(--line-strong);
  font-family: inherit;
  font-size: 0.98rem;
  color: var(--ink);
  transition: border-color 0.15s ease, background 0.15s ease;
}
.tool-card input:focus,
.tool-card select:focus {
  outline: none;
  background: #fff;
  border-bottom-color: var(--accent);
}
.tool-card input[type="number"] { appearance: textfield; -moz-appearance: textfield; }
.tool-card .row2 { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.tool-result {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px dashed var(--line-strong);
}
.predict-list { list-style: none; display: flex; flex-direction: column; gap: 9px; }
.predict-list li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  font-size: 0.92rem;
  padding-bottom: 8px;
  border-bottom: 1px dotted var(--line);
}
.predict-list li:last-child { border-bottom: none; padding-bottom: 0; }
.predict-list .g { font-family: "Fraunces", serif; font-weight: 600; }
.predict-list .need { font-variant-numeric: tabular-nums; font-weight: 700; }
.predict-list .need.ok { color: var(--grade-a); }
.predict-list .need.no { color: var(--grade-f); }
.target-out p { font-size: 0.95rem; line-height: 1.65; margin: 0; }
.target-out .num {
  font-family: "Fraunces", serif;
  font-weight: 600;
  font-size: 1.55rem;
  color: var(--accent-deep);
}
.target-out.bad .num { color: var(--grade-f); }

/* toast */
#toast {
  position: fixed;
  left: 50%;
  bottom: 30px;
  transform: translateX(-50%) translateY(20px);
  background: var(--ink);
  color: var(--paper);
  padding: 12px 22px;
  border-radius: 3px;
  font-size: 0.9rem;
  font-weight: 500;
  box-shadow: 4px 4px 0 var(--accent);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease, transform 0.25s ease;
  z-index: 100000;
  max-width: 90vw;
  text-align: center;
}
#toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

/* modal three-column score row */
#subjectForm .grid3 {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 14px;
}
#subjectForm .grid3 > div { margin-bottom: 0; }

@media (max-width: 820px) {
  .charts,
  .tool-grid { grid-template-columns: 1fr; }
  .toolbar-actions { width: 100%; }
  .toolbar-actions > button { flex: 1; justify-content: center; }
}
@media (max-width: 560px) {
  #subjectForm .grid3 { grid-template-columns: 1fr; gap: 0; }
  #subjectForm .grid3 > div { margin-bottom: 16px; }
  .tool-card .row2 { grid-template-columns: 1fr; gap: 0; }
  .tool-card .row2 > .tool-field { margin-bottom: 14px; }
}

/* print → clean transcript */
@media print {
  body { padding: 0; background: #fff; }
  body::before { display: none; }
  .sheet { box-shadow: none; border: none; max-width: none; }
  #addSubjectBtn,
  #addSemesterBtn,
  .toolbar-actions,
  .sem-actions,
  .sem-empty-add,
  .data-actions,
  td.actions,
  .tools,
  #subjectModal,
  #mb-popup-overlay,
  #toast { display: none !important; }
  .reveal { opacity: 1 !important; transform: none !important; }
  .colophon { border: 1px solid #999; }
  .chart-box, .sem-card, .tool-card { break-inside: avoid; }
}

/* ============ Mèo Béo Studio — Ad popup ============ */
#mb-popup-overlay {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 99999;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background: rgba(34, 31, 26, 0.42);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  font-family: "Be Vietnam Pro", system-ui, sans-serif;
  color: var(--ink);
}
#mb-popup-overlay.mb-show { display: flex; animation: mbFade 0.25s ease-out; }
@keyframes mbFade { from { opacity: 0; } to { opacity: 1; } }

.mb-card {
  position: relative;
  max-width: 400px;
  width: 100%;
  padding: 34px 34px 30px;
  text-align: center;
  background: var(--card);
  border: 1.5px solid var(--ink);
  box-shadow: 14px 16px 0 rgba(34, 31, 26, 0.15);
  animation: mbPopIn 0.34s cubic-bezier(0.16, 1, 0.3, 1);
}
@keyframes mbPopIn {
  from { transform: translateY(18px) rotate(-0.5deg); opacity: 0; }
  to { transform: translateY(0) rotate(0); opacity: 1; }
}

/* corner stamp — labels it honestly as sponsored */
.mb-stamp {
  position: absolute;
  top: 18px;
  left: 22px;
  font-family: "Fraunces", serif;
  font-style: italic;
  font-size: 0.74rem;
  letter-spacing: 0.05em;
  color: var(--mb-accent);
  border: 2px solid var(--mb-accent);
  border-radius: 4px;
  padding: 3px 10px;
  transform: rotate(-5deg);
  opacity: 0.85;
}

.mb-close {
  position: absolute;
  top: 14px;
  right: 20px;
  background: none;
  border: none;
  font-family: "Fraunces", serif;
  font-size: 28px;
  line-height: 1;
  color: var(--ink-faint);
  cursor: pointer;
  z-index: 3;
  transition: color 0.15s ease, transform 0.15s ease;
}
.mb-close:hover { color: var(--mb-accent); transform: rotate(90deg); }

.mb-logo {
  width: 100px;
  height: 100px;
  margin: 12px auto 16px;
  object-fit: cover;
  padding: 5px;
}

.mb-eyebrow {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  font-size: 0.66rem;
  font-weight: 600;
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-bottom: 2px;
}
.mb-eyebrow::before,
.mb-eyebrow::after {
  content: "";
  width: 26px;
  height: 1px;
  background: var(--line-strong);
}

.mb-title {
  font-family: "Fraunces", serif;
  font-weight: 600;
  font-size: 1.68rem;
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--ink);
  margin: 8px 0 10px;
}
.mb-title em { font-style: italic; color: var(--mb-accent); }

.mb-tagline {
  font-size: 0.92rem;
  line-height: 1.6;
  color: var(--ink-soft);
  margin: 0 auto 20px;
  max-width: 300px;
}

.mb-chips {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  margin: 0 0 24px;
  padding: 18px 0 0;
  border-top: 1px solid var(--line);
}
.mb-chip {
  font-size: 0.74rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  padding: 5px 12px;
  border: 1px solid var(--line-strong);
  border-radius: 3px;
  color: var(--ink-soft);
}

.mb-cta {
  display: inline-block;
  width: 100%;
  font-family: inherit;
  font-weight: 600;
  font-size: 0.98rem;
  letter-spacing: 0.02em;
  text-decoration: none;
  color: var(--paper);
  padding: 14px 30px;
  border-radius: 2px;
  background: var(--mb-accent);
  border: 1.5px solid var(--mb-accent);
  box-shadow: 5px 5px 0 var(--ink);
  transition: transform 0.16s ease, box-shadow 0.16s ease, background 0.16s ease;
}
.mb-cta:hover {
  transform: translate(-2px, -2px);
  box-shadow: 7px 7px 0 var(--ink);
  background: var(--mb-accent-deep);
}
.mb-cta:active {
  transform: translate(2px, 2px);
  box-shadow: 2px 2px 0 var(--ink);
}

.mb-later {
  display: block;
  margin: 16px auto 0;
  background: none;
  border: none;
  font-family: inherit;
  font-size: 0.82rem;
  color: var(--ink-faint);
  cursor: pointer;
  transition: color 0.15s ease;
}
.mb-later:hover { color: var(--ink-soft); text-decoration: underline; }

@media (prefers-reduced-motion: reduce) {
  #mb-popup-overlay *, .mb-card { animation: none !important; }
}
@media (max-width: 420px) {
  .mb-card { padding: 30px 22px 26px; }
  .mb-title { font-size: 1.5rem; }
}