:root {
  --blue: #3182f6;
  --blue-weak: #e8f1ff;
  --blue-press: #1b64da;
  --green: #11b87a;
  --green-weak: #e6f7f0;
  --red: #f04452;
  --red-weak: #fde9eb;
  --amber: #f59f00;
  --amber-weak: #fff4e0;
  --ink: #191f28;
  --ink-2: #4e5968;
  --ink-3: #8b95a1;
  --line: #eef0f3;
  --bg: #f2f4f6;
  --card: #ffffff;
  --radius: 16px;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.04), 0 4px 16px rgba(0, 0, 0, 0.04);
  --maxw: 480px;
}

* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html, body { margin: 0; padding: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Pretendard",
    "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.5;
  letter-spacing: -0.01em;
}

.app {
  max-width: var(--maxw);
  margin: 0 auto;
  min-height: 100vh;
  background: var(--bg);
  display: flex;
  flex-direction: column;
  position: relative;
}

/* ---- Top bar ---- */
.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  gap: 4px;
  height: 52px;
  padding: 0 8px;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.topbar__back {
  border: 0;
  background: none;
  font-size: 30px;
  line-height: 1;
  color: var(--ink);
  width: 40px;
  height: 40px;
  cursor: pointer;
}
.topbar__title { font-size: 17px; font-weight: 700; margin: 0; }
.topbar__spacer { flex: 1; }

/* ---- Screen ---- */
.screen {
  flex: 1;
  padding: 16px 20px calc(88px + env(safe-area-inset-bottom));
  overflow-y: auto;
}

/* ---- Tab bar ---- */
.tabbar {
  position: fixed;
  left: 50%;
  transform: translateX(-50%);
  bottom: 0;
  width: 100%;
  max-width: var(--maxw);
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: saturate(180%) blur(12px);
  border-top: 1px solid var(--line);
  padding-bottom: env(safe-area-inset-bottom);
  z-index: 20;
}
.tab {
  border: 0;
  background: none;
  padding: 8px 0 10px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3px;
  font-size: 11px;
  font-weight: 600;
  color: var(--ink-3);
  cursor: pointer;
}
.tab__ico { display: inline-flex; line-height: 1; }
.tab__ico svg { width: 23px; height: 23px; }
.tab.is-active { color: var(--blue); }

/* Lucide icon in a soft-blue rounded square (used in cards / quick links) */
.iconbox {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: 14px;
  background: #eff6ff;
  color: #2563eb;
}
.iconbox svg { width: 28px; height: 28px; }
.iconbox--sm { width: 38px; height: 38px; border-radius: 11px; }
.iconbox--sm svg { width: 22px; height: 22px; }

/* ---- Cards & generic ---- */
.card {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px;
  margin-bottom: 14px;
}
.card__head {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
}
.card__ico { font-size: 18px; }
.card__title { font-size: 16px; font-weight: 700; margin: 0; }
.card__sub { font-size: 13px; color: var(--ink-3); margin: 2px 0 0; }

.hero {
  padding: 14px 2px 8px;
}
.hero h2 {
  font-size: 25px;
  font-weight: 800;
  line-height: 1.36;
  margin: 4px 0 8px;
  letter-spacing: -0.025em;
  word-break: keep-all;
}
.hero p { color: var(--ink-3); margin: 0 0 8px; font-size: 14px; word-break: keep-all; }
.hero--icon { display: flex; align-items: center; gap: 14px; padding-bottom: 8px; }
.hero--icon h2 { margin: 0 0 2px; }
.hero--icon p { margin: 0; }

/* Inputs */
.textarea {
  width: 100%;
  min-height: 150px;
  border: 1.5px solid var(--line);
  border-radius: 14px;
  padding: 14px;
  font: inherit;
  font-size: 15px;
  resize: vertical;
  background: var(--card);
  color: var(--ink);
  outline: none;
  transition: border-color 0.15s;
}
.textarea:focus { border-color: var(--blue); }

/* Toss-style input card: white card wrapping a borderless textarea + footer action */
.field-card {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 6px 6px 4px;
}
.textarea--bare {
  border: 0;
  background: transparent;
  border-radius: 12px;
  min-height: 132px;
  padding: 12px 12px 4px;
  transition: none;
}
.textarea--bare:focus { border: 0; }
.field-card .thumbs { padding: 4px 8px 0; }
.field-card__foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 2px 4px;
}
.linkbtn {
  border: 0;
  background: none;
  font: inherit;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--ink-2);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 9px 10px;
  border-radius: 10px;
}
.linkbtn svg { width: 19px; height: 19px; color: var(--blue); }
.linkbtn b { color: var(--blue); }
.linkbtn:active { background: var(--bg); }
.linkbtn:disabled { opacity: 0.5; cursor: default; }

.input {
  width: 100%;
  border: 1.5px solid var(--line);
  border-radius: 12px;
  padding: 12px 14px;
  font: inherit;
  font-size: 15px;
  outline: none;
  background: var(--card);
}
.input:focus { border-color: var(--blue); }

/* Photo upload */
.upload__add {
  margin-top: 10px;
  width: 100%;
  border: 1.5px dashed #c9d6e8;
  background: var(--card);
  color: var(--ink-2);
  border-radius: 14px;
  padding: 13px;
  font: inherit;
  font-size: 14.5px;
  font-weight: 600;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}
.upload__add svg { width: 20px; height: 20px; color: var(--blue); }
.upload__add b { color: var(--blue); }
.upload__add:disabled { opacity: 0.5; cursor: default; }
.thumbs { display: grid; grid-template-columns: repeat(5, 1fr); gap: 8px; margin-top: 10px; }
.thumbs:empty { display: none; }
.thumb { position: relative; aspect-ratio: 1; border-radius: 12px; overflow: hidden; background: var(--bg); }
.thumb img { width: 100%; height: 100%; object-fit: cover; display: block; }
.thumb__rm {
  position: absolute; top: 3px; right: 3px; width: 20px; height: 20px;
  border: 0; border-radius: 50%; background: rgba(25, 31, 40, 0.72); color: #fff;
  font-size: 14px; line-height: 1; cursor: pointer; padding: 0;
  display: flex; align-items: center; justify-content: center;
}

/* Segmented control */
.seg-label { font-size: 13px; font-weight: 600; color: var(--ink-2); margin: 14px 2px 7px; }
.seg {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}
.seg button {
  flex: 1;
  min-width: fit-content;
  border: 1.5px solid var(--line);
  background: var(--card);
  color: var(--ink-2);
  border-radius: 999px;
  padding: 9px 12px;
  font-size: 13.5px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.12s;
  white-space: nowrap;
}
.seg button.is-on {
  background: var(--blue-weak);
  border-color: var(--blue);
  color: var(--blue-press);
}

/* Buttons */
.btn {
  width: 100%;
  border: 0;
  border-radius: 14px;
  padding: 15px;
  font-size: 16px;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.08s, background 0.12s;
  font-family: inherit;
}
.btn:active { transform: scale(0.985); }
.btn--primary { background: var(--blue); color: #fff; box-shadow: 0 6px 16px rgba(49, 130, 246, 0.24); }
.btn--primary:active { background: var(--blue-press); }
.btn--primary:disabled { background: #c9d3e0; box-shadow: none; cursor: default; }
.btn--ghost { background: var(--bg); color: var(--ink-2); }
.btn--sm { padding: 10px 14px; font-size: 14px; width: auto; border-radius: 10px; }
.btn--lg { padding: 17px; font-size: 16.5px; font-weight: 800; border-radius: 15px; }
.btn-row { display: flex; gap: 8px; margin-top: 12px; }

/* Chips & pills */
.pill {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 11.5px;
  font-weight: 700;
  padding: 3px 9px;
  border-radius: 999px;
  background: var(--bg);
  color: var(--ink-2);
}
.pill--easy { background: var(--green-weak); color: var(--green); }
.pill--natural { background: var(--blue-weak); color: var(--blue-press); }
.pill--adv { background: var(--amber-weak); color: var(--amber); }

/* Example block */
.ex { padding: 12px 0; border-bottom: 1px solid var(--line); }
.ex:last-child { border-bottom: 0; padding-bottom: 0; }
.ex__line { display: flex; gap: 8px; align-items: baseline; margin: 4px 0; }
.ex__en { font-size: 15px; font-weight: 600; flex: 1; }
.ex__ko { color: var(--ink-2); font-size: 13.5px; margin: 6px 0 0; }
/* Korean line: hangul + romanization, with a speaker button */
.ex__kr { flex: 1; min-width: 0; }
.ex__krtext { font-size: 15px; font-weight: 600; }
.ex__roman { display: block; font-size: 12px; color: var(--ink-3); margin-top: 1px; font-style: italic; line-height: 1.3; }
.speak {
  flex: none; border: 0; background: var(--blue-weak); color: var(--blue);
  width: 30px; height: 30px; border-radius: 9px; cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center; align-self: center; padding: 0;
}
.speak svg { width: 17px; height: 17px; }
.speak:active { transform: scale(0.92); }
/* Key words & Grammar chips */
.ex__kw-wrap { margin-top: 10px; display: flex; flex-direction: column; gap: 6px; }
.ex__chips-row { display: flex; align-items: flex-start; gap: 8px; flex-wrap: wrap; }
.ex__chips-label {
  font-size: 11px; font-weight: 700; color: var(--ink-3); text-transform: uppercase;
  letter-spacing: 0.04em; white-space: nowrap; margin-top: 5px; min-width: 64px;
}
.ex__chips { display: flex; flex-wrap: wrap; gap: 5px; }
.kw-chip {
  border: 0; cursor: pointer; font-family: inherit;
  display: inline-flex; align-items: center; gap: 4px;
  padding: 4px 9px; border-radius: 999px;
  background: var(--bg); transition: background 0.1s;
}
.kw-chip__w { font-size: 13px; font-weight: 700; color: var(--ink); }
.kw-chip__sep { font-size: 11px; color: var(--ink-3); }
.kw-chip__m { font-size: 12px; color: var(--ink-2); }
.kw-chip__plus {
  font-size: 13px; font-weight: 700; color: var(--ink-3);
  margin-left: 2px; line-height: 1;
}
.kw-chip.is-active .kw-chip__plus { color: var(--blue); }
.kw-chip--gr { background: #FFF4E0; }
.kw-chip--gr .kw-chip__w { color: #92400E; }
.kw-chip--gr .kw-chip__m { color: #92400E; opacity: 0.75; }
.ex__chips-hint {
  font-size: 12px; color: var(--blue); font-weight: 600;
  margin-top: 4px; display: flex; align-items: center; gap: 4px;
}
.ex__chips-hint::before { content: "👆"; font-size: 13px; }
.kw-chip.is-active { background: var(--blue-weak); }
.kw-chip.is-active .kw-chip__w { color: var(--blue-press); }
.kw-chip.is-active .kw-chip__sep,
.kw-chip.is-active .kw-chip__m { color: var(--blue); }
.kw-chip--gr.is-active { background: var(--amber-weak); }
.kw-chip--gr.is-active .kw-chip__w { color: var(--amber); }

.kw-detail {
  background: var(--card);
  border: 1.5px solid var(--line);
  border-radius: 12px;
  padding: 10px 12px;
  margin-top: 2px;
}
.kw-detail__word { font-size: 16px; font-weight: 800; color: var(--ink); display: flex; align-items: baseline; gap: 8px; }
.kw-detail__pattern { font-size: 15px; font-weight: 800; color: #92400E; }
.kw-detail__roman { font-size: 12px; font-weight: 400; color: var(--ink-3); font-style: italic; }
.kw-detail__meaning { font-size: 13.5px; color: var(--ink-2); margin-top: 4px; }
.kw-detail__note { font-size: 12.5px; color: var(--ink-3); margin-top: 6px; line-height: 1.5; }
.kw-detail__ex { font-size: 12.5px; color: var(--ink-2); margin-top: 6px; line-height: 1.5; border-top: 1px solid var(--line); padding-top: 6px; }

.ex__when {
  margin-top: 8px;
  background: #F3F7FF;
  border-radius: 10px;
  padding: 9px 11px;
  font-size: 12.5px;
  color: var(--ink-2);
}
.ex__when-title { font-weight: 700; color: var(--blue); }

/* Synonyms table */
.syn { display: grid; grid-template-columns: 1fr 1fr 1.1fr; gap: 1px; background: var(--line); border-radius: 12px; overflow: hidden; }
.syn > div { background: var(--card); padding: 9px 10px; font-size: 13px; }
.syn .syn__h { background: var(--bg); font-weight: 700; color: var(--ink-2); font-size: 12px; }
.syn .syn__w { font-weight: 700; }
.syn .syn__n { color: var(--ink-2); }
.syn__roman { display: block; font-size: 11px; color: var(--ink-3); font-style: italic; font-weight: 400; margin-top: 1px; }

/* Summary list */
.sumlist { margin: 0; padding-left: 0; list-style: none; }
.sumlist li {
  display: flex; gap: 9px; padding: 7px 0; font-size: 14.5px; align-items: flex-start;
}
.sumlist li::before {
  content: ""; flex: none; width: 6px; height: 6px; border-radius: 50%;
  background: var(--blue); margin-top: 9px;
}
.byuse { margin-top: 10px; display: grid; gap: 7px; }
.byuse div { font-size: 13px; color: var(--ink-2); }
.byuse b { color: var(--ink); }

/* Quiz */
.quiz__q { font-size: 15.5px; font-weight: 600; margin: 0 0 12px; }
.quiz__opts { display: grid; gap: 8px; }
.quiz__opt {
  text-align: left; border: 1.5px solid var(--line); background: var(--card);
  border-radius: 12px; padding: 12px 14px; font: inherit; font-size: 14.5px; cursor: pointer;
}
.quiz__opt.is-correct { border-color: var(--green); background: var(--green-weak); color: var(--green); font-weight: 700; }
.quiz__opt.is-wrong { border-color: var(--red); background: var(--red-weak); color: var(--red); font-weight: 700; }
.quiz__feedback { margin-top: 12px; font-size: 13.5px; padding: 11px 13px; border-radius: 12px; }
.quiz__feedback.ok { background: var(--green-weak); color: var(--green); }
.quiz__feedback.no { background: var(--red-weak); color: var(--red); }
.quiz__feedback small { display: block; color: var(--ink-2); margin-top: 4px; font-weight: 500; }
.quiz__progress { font-size: 13px; color: var(--ink-3); font-weight: 600; margin-bottom: 10px; }

/* Flashcard */
.flash {
  perspective: 1200px;
  height: 360px;
  margin-bottom: 12px;
  cursor: pointer;
}
.flash__inner {
  position: relative; width: 100%; height: 100%;
  transition: transform 0.45s; transform-style: preserve-3d;
}
.flash.is-flipped .flash__inner { transform: rotateY(180deg); }
.flash__face {
  position: absolute; inset: 0; backface-visibility: hidden;
  border-radius: 28px;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  padding: 24px 20px; text-align: center; overflow: hidden;
}
.flash__front {
  background: var(--card);
  border: 1px solid #EEF1F5;
  box-shadow: 0 12px 32px rgba(15, 23, 42, 0.06);
}
.flash__back {
  background: var(--blue); color: #fff; transform: rotateY(180deg);
  justify-content: center;
}
.flash__front .flash__big { font-size: 28px; font-weight: 800; }
.flash__roman { font-size: 14px; color: var(--ink-3); font-style: italic; margin-top: 4px; }
.flash__hint { font-size: 12px; color: var(--ink-3); margin-top: 16px; }

/* Flash header */
.flash__header { text-align: center; margin-bottom: 10px; }
.flash__title { font-size: 14px; font-weight: 700; color: var(--ink-2); margin-bottom: 7px; }
.flash__prog-bar { height: 4px; background: var(--line); border-radius: 999px; overflow: hidden; margin: 0 2px 6px; }
.flash__prog-fill { height: 100%; background: var(--blue); border-radius: 999px; transition: width 0.35s ease; }
.flash__counter { font-size: 12px; color: var(--ink-3); font-weight: 600; }

/* POS badge */
.flash__pos {
  font-size: 11px; font-weight: 700; padding: 3px 10px; border-radius: 999px;
  background: var(--blue-weak); color: var(--blue-press); margin-bottom: 10px;
}

/* Listen button */
.flash__listen {
  display: inline-flex; align-items: center; gap: 6px;
  background: var(--blue-weak); color: var(--blue);
  padding: 8px 16px; border-radius: 999px;
  font-size: 13px; font-weight: 700; font-family: inherit;
  margin-top: 14px; width: auto; border: 0; cursor: pointer;
}
.flash__listen svg { width: 15px; height: 15px; }

/* Back card */
.flash__back-word { font-size: 18px; font-weight: 800; opacity: 0.88; }
.flash__back-roman { display: block; font-size: 12px; font-weight: 400; font-style: italic; opacity: 0.65; margin-top: 2px; }
.flash__meaning { font-size: 24px; font-weight: 800; margin: 10px 0 12px; }
.flash__ex-block {
  border-top: 1px solid rgba(255,255,255,0.2);
  padding-top: 10px; width: 100%; text-align: center;
}
.flash__ex-label { font-size: 10px; font-weight: 700; opacity: 0.65; text-transform: uppercase; letter-spacing: 0.06em; margin-bottom: 4px; }
.flash__ex-kr { font-size: 14px; font-weight: 600; }
.flash__ex-en { font-size: 12.5px; opacity: 0.78; margin-top: 2px; }
.flash__kws { display: flex; flex-wrap: wrap; gap: 5px; justify-content: center; margin-top: 10px; }
.flash__kw {
  display: inline-flex; align-items: center; gap: 3px;
  background: rgba(255,255,255,0.15); border-radius: 999px; padding: 3px 9px; font-size: 11.5px;
}
.flash__kw-w { font-weight: 700; }
.flash__kw-sep { opacity: 0.55; font-size: 10px; }
.flash__kw-m { opacity: 0.82; }

.flash__rate { display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; }
.flash__rate button {
  border: 0; border-radius: 20px; height: 64px; font-weight: 700; font-size: 15px; cursor: pointer; font-family: inherit;
}
.rate--know { background: var(--green-weak); color: var(--green); }
.rate--meh { background: var(--amber-weak); color: #B45309; }
.rate--no { background: var(--red-weak); color: var(--red); }

/* Wrong-note item */
.wrong { padding: 14px 0; border-bottom: 1px solid var(--line); }
.wrong:last-child { border-bottom: 0; }
.wrong__q { font-size: 14.5px; font-weight: 600; }
.wrong__row { font-size: 13.5px; margin-top: 5px; }
.wrong__row .k { color: var(--ink-3); font-weight: 600; margin-right: 6px; }
.wrong__bad { color: var(--red); }
.wrong__good { color: var(--green); font-weight: 700; }

/* Set list */
.setrow {
  display: flex; align-items: center; gap: 12px; padding: 14px 4px; border-bottom: 1px solid var(--line); cursor: pointer;
}
.setrow:last-child { border-bottom: 0; }
.setrow__ico { font-size: 22px; }
.setrow__body { flex: 1; min-width: 0; }
.setrow__title { font-weight: 700; font-size: 15px; }
.setrow__meta { font-size: 12.5px; color: var(--ink-3); margin-top: 2px; }
.setrow__go { display: inline-flex; color: #c4ccd6; }
.setrow__go svg { width: 20px; height: 20px; }
.day-count { font-size: 12px; font-weight: 600; color: var(--ink-3); margin-left: 2px; }

/* Misc */
.empty { text-align: center; padding: 48px 20px; color: var(--ink-3); }
.empty__ico { font-size: 40px; }
.empty p { margin: 12px 0 0; font-size: 14px; }
.section-title { font-size: 14px; font-weight: 700; color: var(--ink-2); margin: 22px 2px 8px; }
.muted { color: var(--ink-3); font-size: 13px; }
.center { text-align: center; }
.spacer-sm { height: 8px; }

/* Loading */
.loader { display: flex; flex-direction: column; align-items: center; padding: 80px 20px 0; gap: 14px; }
.loader p { color: var(--ink-2); font-size: 15px; font-weight: 700; text-align: center; }
.ld-bar-wrap {
  width: 100%; background: var(--line); border-radius: 999px; height: 8px; overflow: hidden;
}
.ld-bar {
  height: 100%; width: 0%; background: var(--blue);
  border-radius: 999px; transition: width 0.08s linear;
}
.ld-sub { font-size: 12px; color: var(--ink-3); font-weight: 500; margin-top: -4px; }

/* Quick links on home — Toss-style grouped menu list */
.menu-card {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  margin-top: 8px;
}
.menu-card button {
  width: 100%;
  border: 0;
  border-top: 1px solid var(--line);
  background: none;
  cursor: pointer;
  font-family: inherit;
  display: flex;
  align-items: center;
  gap: 13px;
  padding: 14px 16px;
  text-align: left;
}
.menu-card button:first-child { border-top: 0; }
.menu-card button:active { background: var(--bg); }
.menu-row__body { flex: 1; min-width: 0; display: flex; flex-direction: column; }
.menu-row__t { font-weight: 700; font-size: 15px; color: var(--ink); word-break: keep-all; }
.menu-row__d { font-size: 12.5px; color: var(--ink-3); margin-top: 2px; }
.menu-row__go { display: inline-flex; color: #c4ccd6; }
.menu-row__go svg { width: 20px; height: 20px; }

/* Toast */
.toast {
  position: fixed; left: 50%; bottom: 96px; transform: translateX(-50%);
  background: rgba(25, 31, 40, 0.92); color: #fff; padding: 11px 18px; border-radius: 999px;
  font-size: 13.5px; font-weight: 600; z-index: 50; max-width: 88%;
  animation: toastIn 0.2s ease;
}
@keyframes toastIn { from { opacity: 0; transform: translate(-50%, 8px); } }

/* fade-in for views */
.view { animation: fade 0.22s ease; }
@keyframes fade { from { opacity: 0; transform: translateY(6px); } }