/* مرجع التكييف والتدفئة في الكويت — التنسيق العام */
:root {
  --primary: #0b5e6e;
  --primary-dark: #083e49;
  --primary-light: #e0f2f5;
  --accent: #e8a13d;
  --accent-dark: #b97a1e;
  --bg: #f4f7f8;
  --card: #ffffff;
  --text: #1e2a2e;
  --text-soft: #51666c;
  --border: #dde7e9;
  --danger: #c0392b;
  --danger-bg: #fdecea;
  --warn-bg: #fdf6e3;
  --ok: #1e8e5a;
  --ok-bg: #e8f7f0;
  --info-bg: #e8f1fb;
  --info: #2563a8;
  --radius: 14px;
  --sidebar-w: 280px;
  --shadow: 0 1px 3px rgba(8, 62, 73, .08), 0 4px 16px rgba(8, 62, 73, .06);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Tajawal", "Segoe UI", Tahoma, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.8;
  font-size: 16.5px;
}

/* ===== الهيكل العام ===== */
.layout { display: flex; min-height: 100vh; }

.sidebar {
  width: var(--sidebar-w);
  background: linear-gradient(180deg, var(--primary-dark), var(--primary));
  color: #fff;
  position: fixed;
  inset-block: 0;
  inset-inline-start: 0;
  overflow-y: auto;
  z-index: 50;
  padding-bottom: 40px;
  scrollbar-width: thin;
}

.sidebar .brand {
  padding: 22px 20px 14px;
  border-bottom: 1px solid rgba(255,255,255,.15);
}
.sidebar .brand h1 { font-size: 1.15rem; margin: 0 0 4px; color: #fff; }
.sidebar .brand p { margin: 0; font-size: .78rem; color: rgba(255,255,255,.7); }

.sidebar .group-title {
  font-size: .72rem;
  letter-spacing: .5px;
  color: var(--accent);
  padding: 18px 20px 6px;
  text-transform: uppercase;
  font-weight: 700;
}

.sidebar a {
  display: flex;
  align-items: center;
  gap: 10px;
  color: rgba(255,255,255,.88);
  text-decoration: none;
  padding: 9px 20px;
  font-size: .92rem;
  border-inline-start: 3px solid transparent;
  transition: background .15s;
}
.sidebar a:hover { background: rgba(255,255,255,.1); }
.sidebar a.active {
  background: rgba(255,255,255,.14);
  border-inline-start-color: var(--accent);
  font-weight: 700;
  color: #fff;
}
.sidebar a .ico { width: 22px; text-align: center; flex: none; }

.main {
  margin-inline-start: var(--sidebar-w);
  flex: 1;
  min-width: 0;
  padding: 32px clamp(18px, 4vw, 56px) 80px;
  max-width: 1150px;
}

/* شريط علوي للموبايل */
.topbar {
  display: none;
  position: sticky; top: 0; z-index: 60;
  background: var(--primary-dark);
  color: #fff;
  padding: 12px 16px;
  align-items: center;
  justify-content: space-between;
}
.topbar button {
  background: none; border: 1px solid rgba(255,255,255,.4);
  color: #fff; font-size: 1.2rem; border-radius: 8px;
  padding: 4px 12px; cursor: pointer;
}
.topbar .t-title { font-weight: 700; font-size: 1rem; }

@media (max-width: 980px) {
  .sidebar { transform: translateX(100%); transition: transform .25s; }
  [dir="ltr"] .sidebar { transform: translateX(-100%); }
  .sidebar.open { transform: translateX(0); }
  .main { margin-inline-start: 0; padding-top: 18px; }
  .topbar { display: flex; }
}

/* ===== العناوين والنصوص ===== */
.page-head { margin-bottom: 26px; }
.page-head h1 {
  font-size: clamp(1.5rem, 3vw, 2.1rem);
  color: var(--primary-dark);
  margin: 0 0 8px;
}
.page-head .lead { color: var(--text-soft); font-size: 1.05rem; margin: 0; max-width: 75ch; }

h2 {
  color: var(--primary-dark);
  font-size: 1.35rem;
  margin: 38px 0 14px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--primary-light);
}
h2::before { content: "◆ "; color: var(--accent); font-size: .8em; }
h3 { color: var(--primary); font-size: 1.12rem; margin: 26px 0 10px; }
h4 { color: var(--text); font-size: 1rem; margin: 18px 0 8px; }

p { margin: 0 0 12px; max-width: 85ch; }
ul, ol { padding-inline-start: 24px; margin: 0 0 14px; }
li { margin-bottom: 6px; }
li::marker { color: var(--accent-dark); }
strong { color: var(--primary-dark); }

/* ===== البطاقات والشبكات ===== */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 22px;
  box-shadow: var(--shadow);
  margin-bottom: 18px;
}
.card h3:first-child, .card h2:first-child { margin-top: 0; }

.grid { display: grid; gap: 16px; margin: 16px 0; }
.grid.cols-2 { grid-template-columns: repeat(auto-fit, minmax(290px, 1fr)); }
.grid.cols-3 { grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); }

/* ===== الجداول ===== */
.table-wrap { overflow-x: auto; margin: 14px 0 20px; border-radius: 10px; border: 1px solid var(--border); }
table { border-collapse: collapse; width: 100%; background: #fff; font-size: .92rem; }
th {
  background: var(--primary);
  color: #fff;
  padding: 10px 12px;
  text-align: start;
  font-weight: 700;
  white-space: nowrap;
}
td { padding: 9px 12px; border-top: 1px solid var(--border); vertical-align: top; }
tbody tr:nth-child(even) { background: #f7fafb; }
tbody tr:hover { background: var(--primary-light); }
td.num, th.num { direction: ltr; text-align: end; white-space: nowrap; }

/* ===== صناديق التنبيه ===== */
.note, .warn, .danger, .ok-box {
  border-radius: 10px;
  padding: 14px 16px;
  margin: 14px 0;
  border-inline-start: 4px solid;
  font-size: .95rem;
}
.note { background: var(--info-bg); border-color: var(--info); }
.warn { background: var(--warn-bg); border-color: var(--accent-dark); }
.danger { background: var(--danger-bg); border-color: var(--danger); }
.ok-box { background: var(--ok-bg); border-color: var(--ok); }
.note b:first-child, .warn b:first-child, .danger b:first-child, .ok-box b:first-child { display: inline-block; margin-inline-end: 4px; }

/* ===== الشارات ===== */
.badge {
  display: inline-block;
  padding: 2px 10px;
  border-radius: 999px;
  font-size: .76rem;
  font-weight: 700;
  background: var(--primary-light);
  color: var(--primary-dark);
  margin-inline-end: 4px;
  white-space: nowrap;
}
.badge.gold { background: #fdf2dd; color: var(--accent-dark); }
.badge.red { background: var(--danger-bg); color: var(--danger); }
.badge.green { background: var(--ok-bg); color: var(--ok); }

/* ===== أكورديون ===== */
details {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 10px;
  margin-bottom: 10px;
  overflow: hidden;
}
details summary {
  cursor: pointer;
  padding: 13px 18px;
  font-weight: 700;
  color: var(--primary-dark);
  background: #fbfdfe;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 8px;
}
details summary::before { content: "▸"; color: var(--accent); transition: transform .2s; }
details[open] summary::before { transform: rotate(90deg); }
details summary:hover { background: var(--primary-light); }
details .d-body { padding: 6px 18px 16px; border-top: 1px solid var(--border); }

/* ===== التبويبات داخل الصفحة ===== */
.tabs { display: flex; flex-wrap: wrap; gap: 8px; margin: 18px 0 0; }
.tabs button {
  border: 1px solid var(--border);
  background: #fff;
  border-radius: 999px;
  padding: 8px 18px;
  font-family: inherit;
  font-size: .92rem;
  cursor: pointer;
  color: var(--text-soft);
  font-weight: 700;
}
.tabs button.active { background: var(--primary); color: #fff; border-color: var(--primary); }
.tab-panel { display: none; padding-top: 16px; }
.tab-panel.active { display: block; }

/* ===== الحاسبات والنماذج ===== */
.calc {
  background: linear-gradient(135deg, #fbfdfe, var(--primary-light));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
  margin: 18px 0;
}
.calc h3 { margin-top: 0; }
.calc .row { display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); gap: 14px; margin-bottom: 14px; }
.calc label { display: block; font-size: .85rem; font-weight: 700; color: var(--text-soft); margin-bottom: 4px; }
.calc input, .calc select {
  width: 100%;
  padding: 9px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-family: inherit;
  font-size: .95rem;
  background: #fff;
}
.calc input:focus, .calc select:focus { outline: 2px solid var(--primary); border-color: var(--primary); }
.calc .result {
  background: var(--primary-dark);
  color: #fff;
  border-radius: 10px;
  padding: 16px 18px;
  font-size: 1.02rem;
  margin-top: 6px;
}
.calc .result b { color: var(--accent); font-size: 1.25em; }
.calc .result small { color: rgba(255,255,255,.75); display: block; margin-top: 6px; }
button.btn {
  background: var(--accent);
  color: var(--primary-dark);
  border: none;
  border-radius: 8px;
  padding: 10px 26px;
  font-family: inherit;
  font-weight: 700;
  font-size: .98rem;
  cursor: pointer;
}
button.btn:hover { background: var(--accent-dark); color: #fff; }

/* ===== مخططات نصية / أكواد ===== */
.diagram {
  background: #0d2b33;
  color: #d7f0ec;
  border-radius: 10px;
  padding: 18px;
  overflow-x: auto;
  font-family: "Courier New", monospace;
  font-size: .85rem;
  line-height: 1.6;
  direction: ltr;
  text-align: left;
  white-space: pre;
}
code {
  background: var(--primary-light);
  border-radius: 5px;
  padding: 1px 7px;
  font-size: .88em;
  color: var(--primary-dark);
  direction: ltr;
  display: inline-block;
}

/* لوحة بيانات تجريبية */
.nameplate {
  border: 2px solid #888;
  background: repeating-linear-gradient(45deg, #f2f2f0, #f2f2f0 12px, #ededeb 12px, #ededeb 24px);
  border-radius: 8px;
  padding: 18px;
  max-width: 560px;
  font-family: "Courier New", monospace;
  direction: ltr;
  text-align: left;
  font-size: .85rem;
  margin: 14px 0;
}
.nameplate h4 { text-align: center; margin: 0 0 10px; font-family: inherit; }
.nameplate table { background: transparent; font-size: .82rem; }
.nameplate td { border: 1px solid #aaa; padding: 4px 8px; }

/* ===== بطاقات الإحصاء ===== */
.stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 14px; margin: 18px 0; }
.stat {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  text-align: center;
  box-shadow: var(--shadow);
}
.stat .v { font-size: 1.6rem; font-weight: 800; color: var(--primary); }
.stat .l { font-size: .82rem; color: var(--text-soft); }

/* روابط داخل المحتوى */
.main a { color: var(--info); font-weight: 600; }
.main a:hover { color: var(--primary-dark); }

footer.site-footer {
  margin-top: 50px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
  color: var(--text-soft);
  font-size: .85rem;
}

/* ===== الأشكال والمخططات SVG ===== */
figure.fig {
  margin: 18px 0;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 18px 10px;
  box-shadow: var(--shadow);
}
figure.fig svg { width: 100%; height: auto; display: block; }
figure.fig img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 10px;
  object-fit: cover;
}
figure.fig.fig-photo img {
  max-height: 520px;
  object-position: center 45%;
}
figure.fig.fig-photo--window {
  max-width: 640px;
  margin-inline: auto;
}
figure.fig.fig-photo--window img {
  max-height: 320px;
  object-fit: cover;
  object-position: center 40%;
}
figure.fig figcaption {
  text-align: center;
  font-size: .85rem;
  color: var(--text-soft);
  margin-top: 10px;
  font-weight: 600;
}
.svg-label { font-family: "Tajawal", sans-serif; font-weight: 700; }
.svg-sub { font-family: "Tajawal", sans-serif; }

/* ===== بحث القائمة الجانبية ===== */
.nav-search { padding: 12px 16px 4px; }
.nav-search input {
  width: 100%;
  padding: 9px 12px;
  border: 1px solid rgba(255,255,255,.25);
  background: rgba(255,255,255,.1);
  color: #fff;
  border-radius: 8px;
  font-family: inherit;
  font-size: .88rem;
}
.nav-search input::placeholder { color: rgba(255,255,255,.6); }
.nav-search input:focus { outline: 2px solid var(--accent); }
.sidebar a.hidden-by-search { display: none; }
.sidebar .group-title.hidden-by-search { display: none; }

/* ===== أزرار عائمة: طباعة + أعلى ===== */
.fab-stack {
  position: fixed;
  inset-block-end: 22px;
  inset-inline-start: 22px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  z-index: 40;
}
.fab {
  width: 46px; height: 46px;
  border-radius: 50%;
  border: none;
  background: var(--primary);
  color: #fff;
  font-size: 1.2rem;
  cursor: pointer;
  box-shadow: 0 4px 14px rgba(8,62,73,.3);
  display: flex; align-items: center; justify-content: center;
  transition: transform .15s, background .15s, opacity .2s;
}
.fab:hover { background: var(--accent); color: var(--primary-dark); transform: translateY(-2px); }
.fab.hidden { opacity: 0; pointer-events: none; }
@media (max-width: 980px) { .fab-stack { inset-block-end: 16px; inset-inline-start: 12px; } }

/* ===== مسار التنقل (breadcrumb) وبطاقات التنقل بين الصفحات ===== */
.crumb { font-size: .82rem; color: var(--text-soft); margin-bottom: 6px; }
.crumb a { color: var(--info); }
.page-nav {
  display: flex; justify-content: space-between; gap: 12px;
  margin-top: 40px; flex-wrap: wrap;
}
.page-nav a {
  flex: 1 1 220px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 18px;
  background: var(--card);
  text-decoration: none;
  box-shadow: var(--shadow);
  transition: border-color .15s, transform .15s;
}
.page-nav a:hover { border-color: var(--primary); transform: translateY(-2px); }
.page-nav .dir { font-size: .75rem; color: var(--accent-dark); font-weight: 700; }
.page-nav .ttl { color: var(--primary-dark); font-weight: 700; display: block; margin-top: 2px; }
.page-nav a.next { text-align: end; }

/* ===== شريط تقدم القراءة ===== */
#reading-progress {
  position: fixed; inset-block-start: 0; inset-inline-start: 0;
  height: 3px; width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--accent-dark));
  z-index: 100; transition: width .1s;
}

/* ===== الهيرو في الرئيسية ===== */
.hero {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary));
  color: #fff;
  border-radius: var(--radius);
  padding: 32px clamp(20px,4vw,44px);
  margin-bottom: 26px;
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: 20px;
  align-items: center;
}
.hero h1 { color: #fff; margin: 0 0 10px; font-size: clamp(1.6rem,3vw,2.3rem); }
.hero p { color: rgba(255,255,255,.88); margin: 0; max-width: 60ch; }
.hero svg { width: 100%; height: auto; }
@media (max-width: 760px){ .hero { grid-template-columns: 1fr; } .hero .hero-art { display: none; } }


/* ===== الوضع الداكن (زر تبديل + احترام إعداد النظام) ===== */
:root[data-theme="dark"] {
  --bg: #0e1719;
  --card: #17242a;
  --text: #e7eef0;
  --text-soft: #a3b4ba;
  --border: #28383e;
  --primary-light: #1c3036;
  --info-bg: #15262f;
  --warn-bg: #2a2517;
  --danger-bg: #2e1a17;
  --ok-bg: #142a20;
}
/* العناوين تحتاج لوناً فاتحاً لأن primary-dark غامق */
[data-theme="dark"] .page-head h1,
[data-theme="dark"] h2,
[data-theme="dark"] h3,
[data-theme="dark"] h4 { color: #6fcad9; }
[data-theme="dark"] h2 { border-bottom-color: #284750; }
[data-theme="dark"] strong { color: #d8e6e9; }

/* خلفيات فاتحة مثبّتة سابقاً → تصبح داكنة */
[data-theme="dark"] tbody tr:nth-child(even) { background: #1b282e; }
[data-theme="dark"] tbody tr:hover { background: #21353c; }
[data-theme="dark"] .calc { background: linear-gradient(135deg, #16242a, #1a2f37); }
[data-theme="dark"] details summary { background: #16242a; }
[data-theme="dark"] details summary:hover { background: #1d2f36; }
[data-theme="dark"] .tabs button { background: #17242a; color: var(--text-soft); }
[data-theme="dark"] table { background: var(--card); }
[data-theme="dark"] th { background: #0e4a57; }

/* روابط المحتوى أوضح على الداكن */
[data-theme="dark"] .main a { color: #6cb6ef; }
[data-theme="dark"] .main a:hover { color: #9fd8ec; }
[data-theme="dark"] .badge { background: #1c3036; color: #9fd8e2; }
[data-theme="dark"] .badge.gold { background: #3a2c14; color: #f0c478; }
[data-theme="dark"] code { background: #1c3036; color: #9fd8e2; }

/* المخططات ولوحة البيانات مصممة فاتحة → نُبقي خلفيتها فاتحة لتبقى مقروءة */
[data-theme="dark"] figure.fig { background: #f4f7f8; border-color: #2a3a3f; }
[data-theme="dark"] figure.fig figcaption { color: #3a4a4f; }
[data-theme="dark"] .nameplate { color: #1e2a2e; }

/* صناديق التنبيه: النص فاتح */
[data-theme="dark"] .note,
[data-theme="dark"] .warn,
[data-theme="dark"] .danger,
[data-theme="dark"] .ok-box { color: var(--text); }
[data-theme="dark"] input,
[data-theme="dark"] select { background: #11202525; color: var(--text); }

/* طباعة */
@media print {
  .sidebar, .topbar, .fab-stack, #reading-progress, .page-nav { display: none; }
  .main { margin: 0; max-width: 100%; }
  .card, details, figure.fig { box-shadow: none; break-inside: avoid; }
  details[open] .d-body, details .d-body { display: block; }
  details summary::before { display: none; }
  .tab-panel { display: block !important; }
  a { color: #000 !important; text-decoration: none; }
  body { font-size: 11pt; }
}