/* ===========================================================
   Deutsche Lernen — общий стиль (статическая версия, без сборки)
   Подключается на каждой странице: <link rel="stylesheet" href="styles.css">
   ===========================================================

   ШРИФТЫ: используется системный набор (никаких внешних CDN).
   Хотите свой шрифт — положите файлы в /fonts и раскомментируйте:

   @font-face {
     font-family: 'Inter';
     src: url('fonts/Inter-Regular.woff2') format('woff2');
     font-weight: 400; font-display: swap;
   }
   ...затем добавьте 'Inter' в начало --font-base.
*/

:root {
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --pad-sm: 12px;
  --pad-md: 20px;
  --pad-lg: 32px;
  --font-base: system-ui, -apple-system, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;

  /* Палитра — светлая (по умолчанию, тёплая молочная) */
  --bg: #F5F5F0;
  --bg-elev: #FBFAF5;
  --bg-sunk: #EFEEE8;
  --border: #E2E1D8;
  --border-strong: #C9C7BB;
  --text: #1A1A1A;
  --text-muted: #5A5A55;
  --text-dim: #8A8A82;

  --accent: #C9A227;
  --accent-strong: #B08A12;
  --accent-soft: #F5E9B8;
  --accent-bg: #FAF1CC;

  --danger: #C20A0A;
  --danger-soft: #F8D7D7;
  --success: #2E7D4F;
  --success-soft: #D9EBDF;

  --btn-bg: #3D3B34;
  --btn-fg: #F7F6F1;

  --shadow-sm: 0 1px 2px rgba(20,20,16,0.04);
  --shadow-md: 0 2px 8px rgba(20,20,16,0.06), 0 1px 2px rgba(20,20,16,0.04);
  --shadow-lg: 0 8px 24px rgba(20,20,16,0.08), 0 2px 6px rgba(20,20,16,0.04);
}

[data-theme="dark"] {
  --bg: #14130F;
  --bg-elev: #1C1B17;
  --bg-sunk: #0F0E0B;
  --border: #2C2A24;
  --border-strong: #3A3830;
  --text: #F0EFE8;
  --text-muted: #A6A49B;
  --text-dim: #6E6C64;

  --accent: #E5BC3C;
  --accent-strong: #FFCE00;
  --accent-soft: #4A3A0F;
  --accent-bg: #2E2616;

  --danger: #E64545;
  --danger-soft: #3A1A1A;
  --success: #5DBA82;
  --success-soft: #1A2E22;

  --btn-bg: #EAE8DF;
  --btn-fg: #1A1A1A;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.4);
  --shadow-md: 0 2px 8px rgba(0,0,0,0.4), 0 1px 2px rgba(0,0,0,0.3);
  --shadow-lg: 0 8px 24px rgba(0,0,0,0.5), 0 2px 6px rgba(0,0,0,0.3);
}

/* Reset */
*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: var(--font-base);
  background: var(--bg);
  color: var(--text);
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  transition: background-color .2s ease, color .2s ease;
}
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }
img, svg { display: block; max-width: 100%; }
input, textarea { font-family: inherit; }

/* ---------- Layout helpers ---------- */
.wrap { max-width: 760px; margin: 0 auto; padding: 0 20px; }
.stack { display: flex; flex-direction: column; }
.row { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.muted { color: var(--text-muted); }
.dim { color: var(--text-dim); }
.crumb { font-size: 12px; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; color: var(--text-dim); }
.hidden { display: none !important; }

/* ---------- App header ---------- */
.app-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: saturate(140%) blur(10px);
  -webkit-backdrop-filter: saturate(140%) blur(10px);
  border-bottom: 1px solid var(--border);
}
.app-header-inner {
  max-width: 980px; margin: 0 auto; padding: 12px 20px;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.app-logo { display: flex; align-items: center; gap: 10px; }
.app-logo img { width: 44px; height: 44px; border-radius: 50%; }
.header-actions { display: flex; align-items: center; gap: 8px; }
.icon-btn {
  width: 40px; height: 40px; flex-shrink: 0;
  border: 1px solid var(--border); border-radius: var(--radius-sm);
  background: var(--bg-elev); color: var(--text);
  display: inline-flex; align-items: center; justify-content: center;
  transition: background .15s, border-color .15s;
}
.icon-btn:hover { background: var(--bg-sunk); }
.lang-pill { font-size: 12px; font-weight: 700; letter-spacing: .04em; padding: 9px 12px; border-radius: var(--radius-sm); border: 1px solid var(--border); background: var(--bg-elev); color: var(--text-muted); }

/* ---------- Cards ---------- */
.card {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}
.card-pad { padding: var(--pad-lg); }
.card-link { display: flex; align-items: center; gap: 16px; padding: var(--pad-md) var(--pad-lg); transition: border-color .15s, background .15s; }
.card-link:hover { border-color: var(--border-strong); background: var(--bg-sunk); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 10px 18px; border-radius: var(--radius-sm);
  font-size: 14px; font-weight: 600; border: 1px solid transparent;
  transition: background .15s, border-color .15s, transform .1s, color .15s;
  white-space: nowrap;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--btn-bg); color: var(--btn-fg); }
.btn-primary:hover { background: var(--accent-strong); color: #1A1A1A; }
.btn-ghost { background: transparent; border-color: var(--border-strong); color: var(--text); }
.btn-ghost:hover { background: var(--bg-sunk); }
.btn-block { width: 100%; }
.btn-lg { padding: 14px 24px; font-size: 15px; }
.btn-sm { padding: 6px 12px; font-size: 13px; }
.btn:disabled { opacity: .5; cursor: default; }

/* ---------- Tags ---------- */
.tag {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 4px 10px; border-radius: 999px;
  background: var(--bg-sunk); border: 1px solid var(--border);
  font-size: 12px; font-weight: 600; color: var(--text-muted);
}
.tag-level { background: var(--accent-bg); border-color: var(--accent-soft); color: var(--accent-strong); }

/* ---------- Breadcrumb ---------- */
.breadcrumb { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; font-size: 13px; padding: 16px 0 4px; }
.breadcrumb a, .breadcrumb span.bc-item {
  color: var(--text-muted); background: var(--bg-sunk);
  border: 1px solid var(--border); padding: 5px 12px; border-radius: var(--radius-sm);
  transition: color .15s, background .15s, border-color .15s;
}
.breadcrumb a:hover { color: var(--text); background: var(--accent-bg); border-color: var(--accent); }
.breadcrumb .bc-current { color: var(--accent-strong); background: var(--accent-bg); border-color: var(--accent-soft); }
.breadcrumb .bc-sep { color: var(--text-dim); }

/* ---------- Expandable menu (главная) ---------- */
.home-stage { max-width: 476px; margin: 24px auto 60px; display: flex; flex-direction: column; gap: 14px; }
.expand .head {
  width: 100%; text-align: left; display: flex; align-items: center; gap: 16px;
  padding: var(--pad-md) var(--pad-lg); background: transparent;
}
.expand .head h3 { margin: 0; font-size: 24px; line-height: 1.15; flex: 1; }
.chev { color: var(--text-muted); flex-shrink: 0; transition: transform .25s ease; }
.expand.open .chev { transform: rotate(180deg); }
.expand .body { display: grid; grid-template-rows: 0fr; transition: grid-template-rows .32s cubic-bezier(.4,0,.2,1); }
.expand.open .body { grid-template-rows: 1fr; }
.expand .body-inner { overflow: hidden; }
.submenu { display: flex; flex-direction: column; padding: 2px var(--pad-lg) var(--pad-md); }
.submenu a {
  display: block; padding: 11px 14px; margin-left: 32px;
  border-radius: var(--radius-sm); font-size: 18px; font-weight: 600;
  transition: background .15s, color .15s;
}
.submenu a:hover { background: var(--accent-bg); color: var(--accent-strong); }

/* ---------- Generic field ---------- */
.field-input {
  width: 100%; padding: 12px 14px; font-size: 16px;
  color: var(--text); background: var(--bg);
  border: 1px solid var(--border-strong); border-radius: var(--radius-sm);
  outline: none; transition: border-color .15s, box-shadow .15s;
}
.field-input::placeholder { color: var(--text-dim); }
.field-input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }

/* ---------- Search bar (словарь) ---------- */
.search-bar { display: inline-flex; align-items: center; gap: 6px; border: 1px solid var(--border-strong); background: var(--bg); border-radius: 999px; padding: 5px 5px 5px 18px; max-width: 100%; }
.search-bar input { border: none; outline: none; background: transparent; font-size: 16px; color: var(--text); padding: 6px 0; min-width: 160px; flex: 1; }
.search-go { flex-shrink: 0; width: 40px; height: 40px; border-radius: 50%; display: inline-flex; align-items: center; justify-content: center; background: var(--text); color: var(--bg); }
.circle-btn { width: 46px; height: 46px; border-radius: 50%; flex-shrink: 0; display: inline-flex; align-items: center; justify-content: center; transition: background .15s, opacity .15s; }
.circle-add { border: 1.5px solid var(--success); color: var(--success); }
.circle-add:enabled:hover { background: var(--success-soft); }
.circle-remove { border: 1.5px solid var(--danger); color: var(--danger); }
.circle-remove:enabled:hover { background: var(--danger-soft); }
.circle-btn:disabled { opacity: .32; cursor: default; }

/* ---------- Auth pages ---------- */
.auth-body { min-height: 100vh; min-height: 100dvh; display: flex; flex-direction: column; }
.auth-wrap { flex: 1; display: flex; align-items: center; justify-content: center; padding: 48px 20px; }
.auth-card { width: 100%; max-width: 420px; background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius-lg); box-shadow: var(--shadow-lg); padding: 36px 34px 32px; }
.auth-brand { display: flex; flex-direction: column; align-items: center; gap: 14px; margin-bottom: 24px; }
.auth-brand img { width: 96px; height: 96px; border-radius: 50%; }
.auth-title { font-size: 24px; line-height: 1.2; text-align: center; margin: 0 0 6px; }
.auth-sub { text-align: center; color: var(--text-muted); font-size: 14.5px; margin: 0 auto 22px; max-width: 34ch; }
.field { display: flex; flex-direction: column; gap: 7px; margin-bottom: 16px; }
.field label { font-size: 12px; font-weight: 600; letter-spacing: .06em; text-transform: uppercase; color: var(--text-muted); }
.field .hint { font-size: 12px; color: var(--text-dim); letter-spacing: 0; text-transform: none; }
.field-input[aria-invalid="true"] { border-color: var(--danger); box-shadow: 0 0 0 3px var(--danger-soft); }
.auth-links { margin-top: 20px; display: flex; flex-direction: column; gap: 10px; text-align: center; font-size: 14px; }
.auth-links a { color: var(--accent-strong); font-weight: 600; }
.auth-links a:hover { text-decoration: underline; }
.auth-links .sep { height: 1px; background: var(--border); margin: 4px 0; }
.msg { margin: 4px 0 14px; font-size: 14px; line-height: 1.45; border-radius: var(--radius-sm); }
.msg:empty { display: none; }
.msg.error { color: var(--danger); background: var(--danger-soft); padding: 10px 14px; }
.msg.info { color: var(--success); background: var(--success-soft); padding: 10px 14px; }
.auth-footer { text-align: center; padding: 24px 20px 32px; color: var(--text-dim); font-size: 12.5px; }
.auth-controls { position: fixed; top: 16px; right: 16px; display: flex; gap: 8px; z-index: 60; }

/* Tabs (login/register) */
.tabs { display: flex; gap: 4px; padding: 4px; background: var(--bg-sunk); border: 1px solid var(--border); border-radius: var(--radius-sm); margin-bottom: 22px; }
.tabs button { flex: 1; padding: 9px 0; font-size: 14px; font-weight: 600; border-radius: calc(var(--radius-sm) - 2px); color: var(--text-muted); transition: background .15s, color .15s; }
.tabs button.active { background: var(--bg-elev); color: var(--text); box-shadow: var(--shadow-sm); }

/* ---------- Landing ---------- */
.landing { text-align: center; max-width: 640px; margin: 0 auto; padding: 64px 20px; }
.landing img.mark { width: 110px; height: 110px; border-radius: 50%; margin: 0 auto 28px; }
.landing h1 { font-size: clamp(32px, 6vw, 48px); line-height: 1.05; margin: 0 0 16px; letter-spacing: -0.02em; }
.landing .lede { margin: 0 auto 26px; max-width: 48ch; font-size: 17px; color: var(--text-muted); }
.landing-cta { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.landing-cta .btn { min-width: 160px; }
.features { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; margin: 32px auto 0; }

/* ---------- Grammar ---------- */
.level-tabs { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; margin: 8px 0 20px; }
.level-tabs button { padding: 10px 0; border-radius: 999px; font-size: 15px; font-weight: 700; border: 1.5px solid var(--border-strong); background: var(--bg-elev); color: var(--text); transition: all .15s; }
.level-tabs button.active { border-color: var(--accent); background: var(--accent-soft); color: var(--accent-strong); }
.topic-row { display: flex; align-items: center; gap: 14px; padding: 14px var(--pad-lg); border-bottom: 1px solid var(--border); transition: background .15s; cursor: pointer; }
.topic-row:last-child { border-bottom: none; }
.topic-row:hover { background: var(--bg-sunk); }
.topic-num { width: 34px; height: 34px; flex-shrink: 0; border-radius: var(--radius-sm); background: var(--bg-sunk); display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: 13px; color: var(--text-muted); }
.topic-row h4 { margin: 0 0 2px; font-size: 16px; font-weight: 600; }
.topic-row p { margin: 0; font-size: 13px; color: var(--text-muted); }

@media (max-width: 480px) {
  .auth-card { padding: 28px 22px 26px; }
  .landing-cta .btn { width: 100%; }
}