/* =========================================================
   الجدول الدوري التفاعلي — نظام التصميم
   الاتجاه: "دفتر مختبر علمي" — ورق مخطط، حبر كثيف، وميض نحاسي
   كخيوط أداة قياس قديمة، بطاقات عناصر أشبه ببطاقات طيفية.
   ========================================================= */

:root{
  /* ألوان */
  --bg: #EFF3F1;
  --bg-grid: rgba(19,31,42,.055);
  --surface: #FFFFFF;
  --surface-2: #F6F8F7;
  --surface-3: #EAEFEC;
  --ink: #16213A;
  --ink-soft: #34445C;
  --ink-muted: #647082;
  --border: #D7DFDC;
  --border-strong: #B9C4C0;
  --accent: #C08635;
  --accent-dark: #8F5F1F;
  --accent-2: #2F6F5E;
  --accent-2-dark: #1F4C40;
  --danger: #B0452F;
  --radius-sm: 6px;
  --radius: 12px;
  --radius-lg: 20px;
  --shadow-sm: 0 1px 3px rgba(19,31,42,.08);
  --shadow: 0 6px 24px rgba(19,31,42,.10);
  --shadow-lg: 0 20px 60px rgba(19,31,42,.20);

  --font-display: 'Amiri', 'Traditional Arabic', serif;
  --font-body: 'IBM Plex Sans Arabic', 'Segoe UI', Tahoma, sans-serif;
  --font-mono: 'IBM Plex Mono', 'Courier New', monospace;

  --header-h: 68px;
}

[data-theme="dark"]{
  --bg: #10151C;
  --bg-grid: rgba(255,255,255,.045);
  --surface: #171E27;
  --surface-2: #1D2530;
  --surface-3: #232C38;
  --ink: #EAEFF4;
  --ink-soft: #C4CDD9;
  --ink-muted: #8A97A6;
  --border: #2B3543;
  --border-strong: #3B4756;
  --accent: #D9A15C;
  --accent-dark: #F0B979;
  --accent-2: #57B39D;
  --accent-2-dark: #7ED0BB;
  --shadow-sm: 0 1px 3px rgba(0,0,0,.3);
  --shadow: 0 6px 24px rgba(0,0,0,.35);
  --shadow-lg: 0 20px 60px rgba(0,0,0,.5);
}

*,*::before,*::after{ box-sizing:border-box; }
html{ scroll-behavior:smooth; scroll-padding-top: 90px; }
@media (prefers-reduced-motion: reduce){
  html{ scroll-behavior:auto; }
  *,*::before,*::after{ animation-duration:.001ms !important; animation-iteration-count:1 !important; transition-duration:.001ms !important; scroll-behavior:auto !important; }
}

body{
  margin:0;
  background:
    linear-gradient(var(--bg-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--bg-grid) 1px, transparent 1px),
    var(--bg);
  background-size: 28px 28px, 28px 28px, auto;
  color:var(--ink);
  font-family:var(--font-body);
  line-height:1.7;
  -webkit-font-smoothing:antialiased;
}

h1,h2,h3,h4{ font-family:var(--font-display); color:var(--ink); margin:0 0 .5em; line-height:1.3; }
p{ margin:0 0 1em; color:var(--ink-soft); }
a{ color:inherit; }
.container{ max-width:1280px; margin:0 auto; padding:0 24px; }
img{ max-width:100%; display:block; }
button{ font-family:inherit; }

.skip-link{
  position:absolute; right:-999px; top:0; background:var(--accent); color:#fff; padding:10px 16px;
  z-index:999; border-radius:0 0 0 8px;
}
.skip-link:focus{ right:0; }

:focus-visible{ outline:3px solid var(--accent-2); outline-offset:2px; }

/* =============== أزرار عامة =============== */
.btn{
  display:inline-flex; align-items:center; gap:8px; padding:12px 24px; border-radius:999px;
  font-weight:600; font-size:.95rem; text-decoration:none; border:1.5px solid transparent; cursor:pointer;
  transition: transform .15s ease, box-shadow .15s ease, background .15s ease;
}
.btn:hover{ transform:translateY(-1px); }
.btn-primary{ background:var(--ink); color:#fff; box-shadow:var(--shadow-sm); }
.btn-primary:hover{ background:var(--accent-dark); }
.btn-ghost{ background:transparent; border-color:var(--border-strong); color:var(--ink); }
.btn-ghost:hover{ background:var(--surface-2); }

/* =============== الترويسة =============== */
.site-header{
  position:sticky; top:0; z-index:60; height:var(--header-h);
  background:color-mix(in srgb, var(--surface) 88%, transparent);
  backdrop-filter:blur(10px); border-bottom:1px solid var(--border);
}
.header-inner{ height:100%; display:flex; align-items:center; justify-content:space-between; gap:20px; }
.brand{ display:flex; align-items:center; gap:10px; text-decoration:none; color:var(--ink); }
.brand-mark{ color:var(--accent); display:flex; }
.brand-mark svg{ animation: spin 18s linear infinite; }
@media (prefers-reduced-motion: reduce){ .brand-mark svg{ animation:none; } }
@keyframes spin{ to{ transform:rotate(360deg); } }
.brand-text{ display:flex; flex-direction:column; line-height:1.15; }
.brand-text strong{ font-family:var(--font-display); font-size:1.15rem; }
.brand-text em{ font-style:normal; font-size:.7rem; color:var(--ink-muted); letter-spacing:.02em; }

.main-nav .nav-list{ display:flex; gap:28px; list-style:none; margin:0; padding:0; }
.main-nav .nav-list a{ text-decoration:none; color:var(--ink-soft); font-weight:500; font-size:.95rem; position:relative; padding:6px 0; }
.main-nav .nav-list a::after{ content:""; position:absolute; bottom:0; right:0; width:0; height:2px; background:var(--accent); transition:width .2s; }
.main-nav .nav-list a:hover::after{ width:100%; }
.nav-toggle{ display:none; background:none; border:none; cursor:pointer; padding:8px; flex-direction:column; gap:5px; }
.nav-toggle span{ width:22px; height:2px; background:var(--ink); display:block; }

.icon-btn{
  width:40px; height:40px; border-radius:50%; border:1px solid var(--border); background:var(--surface);
  display:flex; align-items:center; justify-content:center; cursor:pointer; color:var(--ink-soft);
}
.icon-btn:hover{ color:var(--accent); border-color:var(--accent); }

/* =============== Hero =============== */
.hero{ position:relative; padding:64px 0 56px; overflow:hidden; }
.hero-inner{ display:grid; grid-template-columns:1.15fr .85fr; gap:40px; align-items:center; }
.eyebrow{
  font-family:var(--font-mono); text-transform:uppercase; letter-spacing:.08em; font-size:.78rem;
  color:var(--accent-2); margin:0 0 10px; font-weight:600;
}
[data-theme="dark"] .eyebrow{ color:var(--accent-2-dark); }
.hero-copy h1{ font-size:clamp(2rem, 4vw, 3.1rem); margin-bottom:.4em; }
.hero-accent{ color:var(--accent); }
.hero-lede{ font-size:1.08rem; max-width:56ch; }
.hero-actions{ display:flex; gap:14px; margin:24px 0 34px; flex-wrap:wrap; }
.hero-stats{ display:flex; gap:34px; flex-wrap:wrap; margin:0; }
.hero-stats dt{ font-family:var(--font-mono); font-size:1.7rem; font-weight:600; color:var(--ink); }
.hero-stats dd{ margin:0; font-size:.82rem; color:var(--ink-muted); }

.hero-visual{
  aspect-ratio:1/1; border-radius:var(--radius-lg); position:relative;
  background:
    radial-gradient(circle at 30% 30%, color-mix(in srgb, var(--accent) 18%, transparent), transparent 60%),
    repeating-linear-gradient(0deg, var(--bg-grid) 0 1px, transparent 1px 26px),
    repeating-linear-gradient(90deg, var(--bg-grid) 0 1px, transparent 1px 26px),
    var(--surface);
  border:1px solid var(--border);
  box-shadow:var(--shadow);
}
.hero-visual::before{
  white-space:pre; position:absolute; inset:0; display:flex; align-items:center; justify-content:center;
  text-align:center; font-family:var(--font-mono); color:var(--ink-muted); opacity:.5; font-size:.85rem; letter-spacing:.15em; padding:20px;
}

.hero-legend{
  position:absolute; inset:0; display:flex; align-items:center; justify-content:center; z-index:2; padding:20px;
}
.hero-element-key{
  max-width:400px; height:auto; border-radius:var(--radius); box-shadow:var(--shadow);
  transition:transform .2s ease;
}
.hero-element-key:hover{ transform:scale(1.03); }

@media (max-width: 980px){
  .hero-legend{ position:relative; }
}

/* =============== المقدمة =============== */
.intro-section{ padding:40px 0 70px; }
.intro-grid{ display:grid; grid-template-columns:repeat(3,1fr); gap:24px; }
.intro-card{
  background:var(--surface); border:1px solid var(--border); border-radius:var(--radius);
  padding:26px 24px; box-shadow:var(--shadow-sm); position:relative;
}
.intro-num{
  font-family:var(--font-mono); color:var(--accent); font-weight:600; font-size:.85rem;
  display:inline-block; margin-bottom:10px;
}
.intro-card h2{ font-size:1.25rem; }
.intro-card p{ font-size:.95rem; }

/* =============== قسم الجدول =============== */
.table-section{ padding:20px 0 80px; }
.section-head{ display:flex; justify-content:space-between; align-items:flex-end; gap:20px; margin-bottom:22px; flex-wrap:wrap; }
.section-head h2{ font-size:2rem; margin:0; }
.section-lede{ max-width:70ch; }

.view-toggle{ display:flex; background:var(--surface-2); border:1px solid var(--border); border-radius:999px; padding:4px; }
.toggle-btn{
  border:none; background:transparent; padding:8px 18px; border-radius:999px; cursor:pointer; font-size:.85rem;
  color:var(--ink-muted); font-weight:600;
}
.toggle-btn.active{ background:var(--ink); color:#fff; }

.controls-bar{ display:flex; gap:14px; flex-wrap:wrap; margin-bottom:14px; align-items:center; }
.search-wrap{
  flex:1 1 320px; display:flex; align-items:center; gap:10px; background:var(--surface); border:1.5px solid var(--border);
  border-radius:999px; padding:10px 18px; box-shadow:var(--shadow-sm);
}
.search-wrap svg{ color:var(--ink-muted); flex-shrink:0; }
.search-wrap input{
  border:none; outline:none; background:transparent; flex:1; font-family:var(--font-body); font-size:.95rem; color:var(--ink);
}
.search-count{ font-family:var(--font-mono); font-size:.78rem; color:var(--accent-2); white-space:nowrap; }

.filter-controls{ display:flex; gap:10px; flex-wrap:wrap; }
.filter-controls select{
  padding:10px 14px; border-radius:6px; border:1.5px solid var(--border); background:var(--surface); color:var(--ink-soft);
  font-family:var(--font-body); font-size:.85rem; cursor:pointer;
}
.btn-reset{
  padding:10px 16px; border-radius:999px; border:1.5px dashed var(--border-strong); background:transparent;
  color:var(--ink-muted); font-size:.85rem; cursor:pointer;
}
.btn-reset:hover{ color:var(--danger); border-color:var(--danger); }

.quick-row{ display:flex; gap:10px; align-items:center; margin-bottom:20px; flex-wrap:wrap; }
.chip-btn{
  display:inline-flex; align-items:center; gap:7px; padding:8px 16px; border-radius:999px; border:1px solid var(--border);
  background:var(--surface); color:var(--ink-soft); font-size:.83rem; cursor:pointer; font-weight:500;
}
.chip-btn:hover{ border-color:var(--accent); color:var(--accent-dark); }
.chip-btn[aria-pressed="true"]{ background:var(--accent); color:#fff; border-color:var(--accent); }
.results-summary{ margin-inline-start:auto; font-family:var(--font-mono); font-size:.8rem; color:var(--ink-muted); }

/* دليل الألوان — بنية هرمية */
.legend{ display:flex; flex-direction:row; gap:14px; margin-bottom:22px; }

.legend-group{
  border:1.5px solid var(--border); border-radius:var(--radius); padding:14px 16px;
  background:var(--surface); box-shadow:var(--shadow-sm); transition:opacity .15s;
}
.legend-group.dim{ opacity:.3; }
.legend-group-title{
  font-family:var(--font-mono); font-size:.72rem; font-weight:700; text-transform:uppercase;
  letter-spacing:.06em; color:var(--accent-2); margin-bottom:10px;
}
[data-theme="dark"] .legend-group-title{ color:var(--accent-2-dark); }

.legend-subgroups{ display:flex; flex-wrap:wrap; gap:10px; }
.legend-subgroup{
  flex:1 1 200px; border:1px solid var(--border); border-radius:8px;
  padding:10px 12px; background:var(--surface-2); transition:opacity .15s;
}
.legend-subgroup.dim{ opacity:.3; }
.legend-subgroup-title{
  font-size:.7rem; font-weight:600; color:var(--ink-muted); margin-bottom:8px;
  padding-bottom:5px; border-bottom:1px dashed var(--border);
}

.legend-group-items{ display:flex; flex-wrap:wrap; gap:6px; }

.legend-group-btn{
  display:inline-block; margin-bottom:10px; padding:5px 14px; border-radius:999px;
  border:1.5px solid var(--accent-2); background:transparent; color:var(--accent-2);
  font-size:.72rem; font-weight:600; cursor:pointer; transition:all .15s;
}
.legend-group-btn:hover{ background:var(--accent-2); color:#fff; }
.legend-group-btn.dim{ opacity:.3; border-color:var(--border); color:var(--ink-muted); }

.legend-item{
  display:inline-flex; align-items:center; gap:7px; padding:5px 11px; border-radius:999px; font-size:.73rem;
  border:1px solid var(--border); background:var(--surface); cursor:pointer; color:var(--ink-soft); font-weight:500;
  transition:opacity .15s;
}
.legend-item .swatch{ width:10px; height:10px; border-radius:3px; flex-shrink:0; }
.legend-item.dim{ opacity:.3; }

@media (max-width: 760px){
  .legend-subgroups{ flex-direction:column; }
  .legend-subgroup{ flex:none; }
}

/* =============== شبكة الجدول الدوري =============== */
.table-scroll{ overflow-x:auto; padding-bottom:14px; -webkit-overflow-scrolling:touch; }
.periodic-grid{
  display:grid;
  grid-template-columns: repeat(18, minmax(58px, 1fr));
  grid-auto-rows: minmax(58px, auto);
  gap:4px;
  min-width:1100px;
}
.periodic-grid.compact{ grid-template-columns: repeat(18, minmax(38px, 1fr)); gap:3px; }

.el-tile{
  border-radius:7px; border:1px solid transparent; cursor:pointer; position:relative; overflow:hidden;
  display:flex; flex-direction:column; justify-content:center; padding:4px 6px;
  background:var(--tile-bg, var(--surface-3)); color:var(--tile-text, var(--ink));
  transition: transform .12s ease, box-shadow .12s ease, z-index 0s;
  text-align:right;
}
.el-tile:hover, .el-tile:focus-visible{
  transform:scale(1.12); z-index:5; box-shadow:var(--shadow-lg); border-color:rgba(0,0,0,.15);
}
.el-tile:active{ transform:scale(1.05); }
.el-tile .num{ font-family:var(--font-mono); font-size:.62rem; opacity:.85; }
.el-tile .sym{ font-family:var(--font-mono); font-weight:600; font-size:1.05rem; line-height:1.1; }
.el-tile .nameAr{ font-size:.58rem; line-height:1.15; white-space:nowrap; overflow:hidden; text-overflow:ellipsis; }
.el-tile .mass{ font-size:.5rem; font-family:var(--font-mono); opacity:.75; }
.periodic-grid.compact .el-tile .nameAr,
.periodic-grid.compact .el-tile .mass{ display:none; }
.periodic-grid.compact .el-tile .sym{ font-size:.85rem; }

.el-tile.dimmed{ opacity:.18; pointer-events:none; }
.el-tile.fav-marked::after{
  content:"★"; position:absolute; top:2px; left:3px; font-size:.6rem; color:#fff; text-shadow:0 0 2px rgba(0,0,0,.5);
}
.el-tile.ghost{
  background:var(--surface-2) !important; color:var(--ink-muted) !important; display:flex; align-items:center; justify-content:center;
  font-family:var(--font-mono); font-size:.62rem; text-align:center; cursor:pointer; border:1px dashed var(--border-strong);
}
.el-placeholder{ visibility:hidden; }

.table-hint{ font-size:.82rem; color:var(--ink-muted); margin-top:10px; }

/* =============== لوحة/درج تفاصيل العنصر =============== */
.drawer-overlay{
  position:fixed; inset:0; background:rgba(10,14,20,.5); backdrop-filter:blur(2px); z-index:80;
  opacity:0; pointer-events:none; transition:opacity .25s ease;
}
.drawer-overlay.open{ opacity:1; pointer-events:auto; }
.element-drawer{
  position:fixed; top:0; bottom:0; left:0; width:min(560px, 100vw); max-width:100vw;
  background:var(--surface); z-index:90; box-shadow:var(--shadow-lg); overflow-y:auto;
  transform:translateX(-105%); transition:transform .3s cubic-bezier(.2,.9,.3,1);
}
.element-drawer.open{ transform:translateX(0); }
.drawer-close{
  position:sticky; top:14px; float:left; margin:14px; z-index:2; width:38px; height:38px; border-radius:50%;
  border:1px solid var(--border); background:var(--surface); cursor:pointer; display:flex; align-items:center; justify-content:center;
  color:var(--ink-soft);
}
.drawer-close:hover{ color:var(--danger); border-color:var(--danger); }
.drawer-content{ padding:20px 26px 60px; }

.dr-head{ display:flex; align-items:flex-start; gap:18px; margin-bottom:20px; }
.dr-tile{
  width:84px; height:84px; border-radius:14px; flex-shrink:0; display:flex; flex-direction:column;
  align-items:center; justify-content:center; box-shadow:var(--shadow-sm);
}
.dr-tile .sym{ font-family:var(--font-mono); font-size:1.9rem; font-weight:700; }
.dr-tile .num{ font-family:var(--font-mono); font-size:.7rem; opacity:.85; }
.dr-titles{ padding-top:4px; flex:1; }
.dr-titles h2{ font-size:1.55rem; margin-bottom:2px; }
.dr-titles .en{ font-family:var(--font-mono); color:var(--ink-muted); font-size:.9rem; }
.dr-badges{ display:flex; gap:6px; margin-top:8px; flex-wrap:wrap; }
.dr-badge{ font-size:.7rem; padding:4px 10px; border-radius:999px; background:var(--surface-2); border:1px solid var(--border); color:var(--ink-soft); }
.dr-badge.radioactive{ background:color-mix(in srgb, var(--danger) 14%, transparent); color:var(--danger); border-color:transparent; }
.dr-fav{
  border:1.5px solid var(--border); background:var(--surface); border-radius:999px; padding:8px 14px; cursor:pointer;
  font-size:.8rem; display:flex; gap:6px; align-items:center; color:var(--ink-soft);
}
.dr-fav[aria-pressed="true"]{ background:var(--accent); color:#fff; border-color:var(--accent); }

.dr-image-wrap{
  margin-bottom:22px; border-radius:var(--radius); overflow:hidden;
  border:1px solid var(--border); box-shadow:var(--shadow-sm); background:var(--surface-2);
}
.dr-image{
  width:100%; height:auto; display:block; max-height:300px; object-fit:cover;
}

.dr-summary{ font-size:.98rem; margin-bottom:22px; }

.dr-section{ margin-bottom:26px; }
.dr-section h3{
  font-family:var(--font-mono); font-size:.78rem; text-transform:uppercase; letter-spacing:.06em; color:var(--accent-2);
  border-bottom:1px solid var(--border); padding-bottom:8px; margin-bottom:12px; font-weight:600;
}
[data-theme="dark"] .dr-section h3{ color:var(--accent-2-dark); }

.dr-facts{ display:grid; grid-template-columns:1fr 1fr; gap:10px 16px; }
.dr-fact{ font-size:.85rem; }
.dr-fact dt{ color:var(--ink-muted); font-size:.72rem; margin-bottom:2px; }
.dr-fact dd{ margin:0; font-weight:600; font-family:var(--font-mono); font-size:.88rem; }

.dr-uses{ list-style:none; padding:0; margin:0; display:flex; flex-direction:column; gap:8px; }
.dr-uses li{
  font-size:.88rem; padding:9px 12px; background:var(--surface-2); border-radius:8px; border-inline-start:3px solid var(--accent);
  color:var(--ink-soft);
}

.dr-history{ font-size:.88rem; }
.dr-history table{ width:100%; border-collapse:collapse; font-size:.85rem; }
.dr-history td{ padding:6px 4px; border-bottom:1px dashed var(--border); }
.dr-history td:first-child{ color:var(--ink-muted); width:40%; }

/* =============== الاتجاهات =============== */
.trends-section{ padding:60px 0; background:var(--surface-2); border-top:1px solid var(--border); border-bottom:1px solid var(--border); }
.trends-tabs, .tools-tabs{ display:flex; gap:8px; flex-wrap:wrap; margin:18px 0 20px; }
.trend-tab, .tool-tab{
  padding:10px 20px; border-radius:999px; border:1.5px solid var(--border); background:var(--surface); cursor:pointer;
  font-size:.88rem; color:var(--ink-soft); font-weight:500;
}
.trend-tab.active, .tool-tab.active{ background:var(--ink); color:#fff; border-color:var(--ink); }
.trend-chart-wrap{ background:var(--surface); border:1px solid var(--border); border-radius:var(--radius); padding:20px; box-shadow:var(--shadow-sm); }
#trendChart{ width:100%; height:auto; display:block; }
.trend-note{ margin:12px 0 0; font-size:.85rem; color:var(--ink-muted); }

/* =============== أدوات التعلم =============== */
.tools-section{ padding:60px 0; }
.tool-panel{ display:none; }
.tool-panel.active{ display:block; }

.quiz-box{
  background:var(--surface); border:1px solid var(--border); border-radius:var(--radius-lg); padding:36px;
  max-width:640px; margin:0 auto; box-shadow:var(--shadow-sm); text-align:center;
}
.quiz-start h3, .quiz-result h3{ font-size:1.4rem; }
.quiz-active{ text-align:right; }
.quiz-progress{ height:6px; background:var(--surface-3); border-radius:99px; overflow:hidden; margin-bottom:14px; }
.quiz-progress-bar{ height:100%; background:var(--accent-2); width:10%; transition:width .3s; }
.quiz-meta{ font-family:var(--font-mono); font-size:.82rem; color:var(--ink-muted); }
.quiz-options{ display:grid; grid-template-columns:1fr 1fr; gap:10px; margin-top:16px; }
.quiz-opt{
  padding:14px; border-radius:10px; border:1.5px solid var(--border); background:var(--surface-2); cursor:pointer;
  font-size:.95rem; text-align:center; font-weight:500; color:var(--ink);
}
.quiz-opt:hover{ border-color:var(--accent); }
.quiz-opt.correct{ background:color-mix(in srgb, #3f9765 22%, var(--surface)); border-color:#3f9765; }
.quiz-opt.wrong{ background:color-mix(in srgb, var(--danger) 18%, var(--surface)); border-color:var(--danger); }
.quiz-opt[disabled]{ cursor:default; }

.flashcard-box{ max-width:420px; margin:0 auto; text-align:center; }
.flashcard{ perspective:1200px; height:260px; cursor:pointer; }
.flashcard-inner{
  position:relative; width:100%; height:100%; transition:transform .5s; transform-style:preserve-3d;
}
.flashcard.flipped .flashcard-inner{ transform:rotateY(180deg); }
.flashcard-face{
  position:absolute; inset:0; backface-visibility:hidden; border-radius:var(--radius-lg); display:flex; flex-direction:column;
  align-items:center; justify-content:center; box-shadow:var(--shadow); border:1px solid var(--border); padding:20px;
}
.flashcard-front{ background:var(--surface); }
.flashcard-front .sym{ font-family:var(--font-mono); font-size:3.2rem; font-weight:700; }
.flashcard-front .num{ font-family:var(--font-mono); color:var(--ink-muted); }
.flashcard-back{ background:var(--ink); color:#fff; transform:rotateY(180deg); text-align:right; overflow-y:auto; }
.flashcard-back h4{ color:#fff; margin-bottom:6px; }
.flashcard-back p{ color:#cfd8e3; font-size:.85rem; margin:4px 0; }
.flashcard-controls{ display:flex; justify-content:center; gap:10px; margin-top:18px; }
.flash-hint{ font-size:.8rem; color:var(--ink-muted); margin-top:10px; }

.compare-box{ max-width:900px; margin:0 auto; }
.compare-pickers{ display:flex; align-items:center; gap:16px; justify-content:center; margin-bottom:20px; flex-wrap:wrap; }
.compare-pickers select{
  padding:12px 18px; border-radius:10px; border:1.5px solid var(--border); background:var(--surface); font-size:1rem; min-width:220px;
}
.vs{ font-family:var(--font-mono); color:var(--ink-muted); font-weight:600; }
.compare-table-wrap{ overflow-x:auto; }
.compare-table{ width:100%; border-collapse:collapse; background:var(--surface); border-radius:var(--radius); overflow:hidden; box-shadow:var(--shadow-sm); }
.compare-table th, .compare-table td{ padding:12px 16px; border-bottom:1px solid var(--border); font-size:.9rem; text-align:center; }
.compare-table th{ background:var(--surface-2); font-family:var(--font-mono); font-size:.78rem; color:var(--ink-muted); text-transform:uppercase; }
.compare-table td:first-child{ text-align:right; color:var(--ink-muted); font-size:.82rem; }

/* =============== المسرد =============== */
.glossary-section{ padding:60px 0; }
.glossary-grid{ display:grid; grid-template-columns:repeat(auto-fill, minmax(260px,1fr)); gap:16px; margin-top:20px; }
.glossary-item{ background:var(--surface); border:1px solid var(--border); border-radius:var(--radius); padding:18px 20px; box-shadow:var(--shadow-sm); }
.glossary-item h4{ font-size:1.02rem; margin-bottom:2px; }
.glossary-item .en{ font-family:var(--font-mono); font-size:.72rem; color:var(--ink-muted); margin-bottom:8px; display:block; }
.glossary-item p{ font-size:.85rem; margin:0; }

/* =============== حول =============== */
.about-section{ padding:60px 0 80px; }
.about-grid{ display:grid; grid-template-columns:1.4fr .9fr; gap:40px; }
.about-grid h2{ font-size:1.7rem; }
.ref-card{ background:var(--surface); border:1px solid var(--border); border-radius:var(--radius); padding:24px; box-shadow:var(--shadow-sm); }
.ref-card ul{ padding-inline-start:20px; margin:0; }
.ref-card li{ font-size:.88rem; color:var(--ink-soft); margin-bottom:8px; }

/* =============== التذييل =============== */
.site-footer{ background:var(--ink); color:#cfd8e3; padding:50px 0 0; }
[data-theme="dark"] .site-footer{ background:#0B0F14; }
.footer-grid{ display:grid; grid-template-columns:1.4fr 1fr 1fr; gap:30px; padding-bottom:30px; }
.footer-brand{ display:flex; gap:10px; align-items:flex-start; }
.footer-brand .brand-mark{ color:var(--accent); flex-shrink:0; }
.footer-brand p{ color:#9fb0c2; font-size:.88rem; }
.footer-links h4{ color:#fff; font-family:var(--font-body); font-size:.9rem; margin-bottom:12px; }
.footer-links ul{ list-style:none; padding:0; margin:0; display:flex; flex-direction:column; gap:8px; }
.footer-links a{ color:#9fb0c2; text-decoration:none; font-size:.86rem; }
.footer-links a:hover{ color:#fff; }
.footer-bottom{ border-top:1px solid rgba(255,255,255,.1); padding:18px 24px; }
.footer-bottom p{ margin:0; font-size:.78rem; color:#7c8ba0; text-align:center; }
.footer-attribution{ margin-top:10px !important; display:flex; align-items:center; justify-content:center; gap:6px; }
.footer-attribution a{ color:#9fb0c2; text-decoration:none; }
.footer-attribution a:hover{ color:#fff; text-decoration:underline; }
.wikimedia-icon{ width:14px; height:14px; flex-shrink:0; opacity:.7; }

/* =============== قسم التبويبات (محاكاة + مفتاح الألوان) =============== */
.info-tabs{
  display:flex; gap:4px; background:var(--surface-2); border:1px solid var(--border);
  border-radius:var(--radius); padding:6px; margin-bottom:24px; margin-top:8px;
}
.info-tab{
  flex:1; display:flex; align-items:center; justify-content:center; gap:8px;
  padding:14px 20px; border-radius:var(--radius-sm); border:none;
  background:transparent; cursor:pointer; font-family:var(--font-body);
  font-size:.92rem; font-weight:500; color:var(--ink-muted);
  transition: all .2s ease;
}
.info-tab:hover{ background:var(--surface); color:var(--ink-soft); }
.info-tab.active{ background:var(--surface); color:var(--ink); box-shadow:var(--shadow-sm); }
.info-tab svg{ flex-shrink:0; opacity:.6; }
.info-tab.active svg{ opacity:1; }
.info-panel{ display:none; }
.info-panel.active{ display:block; }

.sim-panel .section-lede{ margin:0 0 14px; font-size:.88rem; color:var(--ink-muted); }
.legend-panel{
  background:var(--surface); border:1px solid var(--border); border-radius:var(--radius);
  padding:16px 20px; margin-bottom:16px; box-shadow:var(--shadow-sm);
}

/* =============== استجابة =============== */
@media (max-width: 980px){
  .hero-inner{ grid-template-columns:1fr; }
  .hero-visual{ order:-1; max-width:340px; margin:0 auto; }
  .intro-grid{ grid-template-columns:1fr; }
  .about-grid{ grid-template-columns:1fr; }
  .footer-grid{ grid-template-columns:1fr; }
  .dr-facts{ grid-template-columns:1fr 1fr; }
}
@media (max-width: 760px){
  .nav-toggle{ display:flex; }
  .nav-list{
    position:fixed; inset-inline-end:0; top:var(--header-h); bottom:0; width:min(280px,80vw); background:var(--surface);
    flex-direction:column; padding:24px; gap:22px !important; transform:translateX(105%); transition:transform .25s;
    box-shadow:var(--shadow-lg); border-inline-start:1px solid var(--border);
  }
  .nav-list.open{ transform:translateX(0); }
  .quiz-options{ grid-template-columns:1fr; }
  .element-drawer{ width:100vw; }
  .compare-pickers select{ min-width:0; flex:1; }
}