/* /css/main.css */

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/* 1. المتغيرات المركزية والتصميم المعماري (:root Design Tokens)              */
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:root {
  /* لوحة الألوان الأساسية ونظام التباين الصارم */
  --bg-main: #0b0f19;
  --bg-surface: #111827;
  --bg-surface-elevated: #1f293d;
  --bg-surface-hover: #2d3748;
  
  --border-subtle: #1f2937;
  --border-focus: #3b82f6;
  --border-active: rgba(59, 130, 246, 0.4);

  --text-primary: #f9fafb;
  --text-secondary: #9ca3af;
  --text-muted: #6b7280;
  
  --accent-brand: #3b82f6;
  --accent-brand-hover: #2563eb;
  --accent-success: #10b981;
  --accent-danger: #ef4444;

  /* المقياس المطاطي للأبعاد والخطوط بتابع clamp */
  --font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans Arabic", "Almarai", sans-serif;
  --font-size-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.8125rem);
  --font-size-sm: clamp(0.8438rem, 0.8rem + 0.22vw, 0.9375rem);
  --font-size-base: clamp(0.9375rem, 0.9rem + 0.25vw, 1.0625rem);
  --font-size-lg: clamp(1.125rem, 1.05rem + 0.38vw, 1.3125rem);
  --font-size-xl: clamp(1.375rem, 1.25rem + 0.63vw, 1.75rem);

  /* القياسات الحركية والتخطيط الهيكلي */
  --header-block-size: clamp(3.75rem, 7vh, 4.25rem);
  --dock-block-size: clamp(4.5rem, 8.5vh, 5.25rem);
  --nav-block-size: clamp(3.75rem, 7vh, 4.25rem);
  --border-radius-sm: 0.5rem;
  --border-radius-md: 0.75rem;
  --border-radius-lg: 1rem;
  --border-radius-full: 9999px;

  /* ثوابت سلاسة الإطارات الفائقة (120fps Transitions) */
  --ease-out-quint: cubic-bezier(0.22, 1, 0.36, 1);
  --transition-fast: 150ms var(--ease-out-quint);
  --transition-normal: 250ms var(--ease-out-quint);
}

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/* 2. تصفير البيئة، قفل الجذر، واحتواء الحواف (Viewport Containment)         */
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*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

/* قفل تمرير الجذر ومنع ارتداد السحب على مستوى الهيكل العام */
html,
body {
  inline-size: 100%;
  block-size: 100%;
  block-size: 100dvh;
  overflow: hidden;
  overscroll-behavior: none;
  background-color: var(--bg-main);
  color: var(--text-primary);
  font-family: var(--font-family);
  line-height: 1.5;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

/* فرض إخفاء الرموز بقاعدة قسرية لمنع الحجز الهيكلي الفارغ */
svg[hidden] {
  display: none !important;
}

.icon {
  inline-size: 1.25rem;
  block-size: 1.25rem;
  flex-shrink: 0;
  pointer-events: none;
}

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/* 3. حاوية التطبيق المركزية ومراعاة الحواف الآمنة للهواتف                    */
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.app-root {
  inline-size: 100%;
  block-size: 100%;
  max-inline-size: 48rem; /* محاذاة مركزية ممتازة للأجهزة اللوحية والشاشات العريضة */
  margin-inline: auto;
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
  /* ضبط الحواف الآمنة (Notch & Home Indicator) */
  padding-block-start: env(safe-area-inset-top, 0px);
  padding-inline-end: env(safe-area-inset-right, 0px);
  padding-inline-start: env(safe-area-inset-left, 0px);
}

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/* 4. ترويسة التطبيق العليا (App Header)                                      */
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.app-header {
  block-size: var(--header-block-size);
  inline-size: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-inline: 1.25rem;
  background-color: rgba(11, 15, 25, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-block-end: 1px solid var(--border-subtle);
  z-index: 30;
  flex-shrink: 0;
}

.header-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.brand-title {
  font-size: var(--font-size-lg);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

.brand-badge {
  font-size: var(--font-size-xs);
  font-weight: 500;
  padding-block: 0.125rem;
  padding-inline: 0.5rem;
  border-radius: var(--border-radius-full);
  background-color: rgba(16, 185, 129, 0.15);
  color: var(--accent-success);
  border: 1px solid rgba(16, 185, 129, 0.25);
}

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/* 5. واجهة البحث السريع                                                      */
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.search-container {
  padding-block: 0.75rem;
  padding-inline: 1.25rem;
  background-color: var(--bg-surface);
  border-block-end: 1px solid var(--border-subtle);
  z-index: 25;
}

.search-container[hidden] {
  display: none !important;
}

.search-input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.search-icon {
  position: absolute;
  inset-inline-start: 0.875rem;
  color: var(--text-muted);
}

.search-input {
  inline-size: 100%;
  block-size: 2.75rem;
  padding-inline-start: 2.75rem;
  padding-inline-end: 2.75rem;
  background-color: var(--bg-main);
  border: 1px solid var(--border-subtle);
  border-radius: var(--border-radius-md);
  color: var(--text-primary);
  font-family: inherit;
  font-size: var(--font-size-sm);
  outline: none;
  transition: border-color var(--transition-fast);
}

.search-input:focus {
  border-color: var(--border-focus);
}

.search-clear {
  position: absolute;
  inset-inline-end: 0.5rem;
  display: none;
}

.search-input:not(:placeholder-shown) ~ .search-clear {
  display: flex;
}

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/* 6. المنفذ الرئيسي وإدارة التمرير المقيدة (Main Viewport)                    */
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.main-viewport {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
  overscroll-behavior-y: contain;
  -webkit-overflow-scrolling: touch;
  padding-inline: 1.25rem;
  padding-block-start: 1rem;
  /* هامش أمان سفلي ديناميكي لحماية المحتوى من الحجب خلف المشغل والشريط وقفل لوحة المفاتيح */
  padding-block-end: calc(var(--dock-block-size) + var(--nav-block-size) + env(safe-area-inset-bottom, 0px) + 2rem);
  scroll-padding-block-end: calc(var(--dock-block-size) + var(--nav-block-size) + env(safe-area-inset-bottom, 0px) + 2rem);
}

.view-panel {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.view-panel[hidden] {
  display: none !important;
}

.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block-end: 0.5rem;
}

.section-title {
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--text-secondary);
}

.section-counter {
  font-size: var(--font-size-xs);
  color: var(--text-muted);
}

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/* 7. قائمة المواد الصوتية وعزل الأداء (Content-Visibility Engine)             */
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.tracks-list {
  display: flex;
  flex-direction: column;
  gap: 0.625rem;
}

.track-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block: 0.75rem;
  padding-inline: 1rem;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--border-radius-md);
  /* تسريع التمرير عبر حجز الأبعاد وعزل التخطيط المعماري للقوائم الطويلة */
  content-visibility: auto;
  contain-intrinsic-size: auto 4.75rem;
  touch-action: manipulation;
  transition: transform var(--transition-fast), background-color var(--transition-fast), border-color var(--transition-fast);
}

.track-item:active {
  transform: scale(0.985);
  background-color: var(--bg-surface-hover);
}

.track-item.is-playing {
  border-color: var(--border-active);
  background-color: rgba(59, 130, 246, 0.08);
}

.track-info {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  overflow: hidden;
}

.track-name {
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.track-meta {
  font-size: var(--font-size-xs);
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.track-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-shrink: 0;
}

/* -------------------------------------------------------------------------- */
/* 8. المشغل الصوتي الأحادي العائم (Singleton Audio Dock)                     */
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.audio-dock {
  position: absolute;
  inset-inline: 1rem;
  inset-block-end: calc(var(--nav-block-size) + env(safe-area-inset-bottom, 0px) + 0.5rem);
  block-size: var(--dock-block-size);
  background-color: rgba(17, 24, 39, 0.95);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--border-radius-lg);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.45);
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding-inline: 1rem;
  z-index: 40;
  touch-action: manipulation;
  will-change: transform;
  transform: translateZ(0);
}

/* مسار شريط السحب الزمني */
.dock-scrubber-wrapper {
  inline-size: 100%;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-block-end: 0.375rem;
}

.time-readout {
  font-size: var(--font-size-xs);
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
  min-inline-size: 2.5rem;
  text-align: center;
}

.seek-slider {
  flex: 1;
  -webkit-appearance: none;
  appearance: none;
  background: transparent;
  cursor: pointer;
  block-size: 1.25rem;
}

.seek-slider:focus {
  outline: none;
}

/* مقبض ومسار شريط التمرير على متصفحات WebKit */
.seek-slider::-webkit-slider-runnable-track {
  inline-size: 100%;
  block-size: 0.25rem;
  background-color: var(--border-subtle);
  border-radius: var(--border-radius-full);
}

.seek-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  block-size: 0.75rem;
  inline-size: 0.75rem;
  border-radius: var(--border-radius-full);
  background-color: var(--accent-brand);
  margin-block-start: -0.25rem;
  transition: transform var(--transition-fast);
}

.seek-slider:active::-webkit-slider-thumb {
  transform: scale(1.3);
}

/* مقبض ومسار شريط التمرير على Firefox */
.seek-slider::-moz-range-track {
  inline-size: 100%;
  block-size: 0.25rem;
  background-color: var(--border-subtle);
  border-radius: var(--border-radius-full);
}

.seek-slider::-moz-range-thumb {
  block-size: 0.75rem;
  inline-size: 0.75rem;
  border: none;
  border-radius: var(--border-radius-full);
  background-color: var(--accent-brand);
  transition: transform var(--transition-fast);
}

.dock-controls-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.dock-track-details {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  max-inline-size: 60%;
}

.dock-title {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.dock-artist {
  font-size: var(--font-size-xs);
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.dock-buttons {
  display: flex;
  align-items: center;
  gap: 0.375rem;
}

/* -------------------------------------------------------------------------- */
/* 9. شريط التنقل السفلي للهواتف (Bottom Navigation)                           */
/* -------------------------------------------------------------------------- */
.bottom-navigation {
  position: absolute;
  inset-inline: 0;
  inset-block-end: 0;
  block-size: calc(var(--nav-block-size) + env(safe-area-inset-bottom, 0px));
  padding-block-end: env(safe-area-inset-bottom, 0px);
  background-color: rgba(11, 15, 25, 0.95);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-block-start: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-around;
  z-index: 50;
}

.nav-tab {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.25rem;
  block-size: 100%;
  color: var(--text-muted);
  background: transparent;
  border: none;
  cursor: pointer;
  touch-action: manipulation;
  transition: color var(--transition-fast);
}

.nav-tab.active {
  color: var(--accent-brand);
}

.nav-label {
  font-size: var(--font-size-xs);
  font-weight: 500;
}

/* -------------------------------------------------------------------------- */
/* 10. الأزرار العامة والتفاعلية اللمسية (Buttons Engine)                     */
/* -------------------------------------------------------------------------- */
.btn-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  inline-size: 2.5rem;
  block-size: 2.5rem;
  border-radius: var(--border-radius-full);
  background: transparent;
  color: var(--text-secondary);
  border: none;
  cursor: pointer;
  touch-action: manipulation;
  transition: background-color var(--transition-fast), color var(--transition-fast), transform var(--transition-fast);
  text-decoration: none;
}

.btn-icon:hover {
  background-color: var(--bg-surface-hover);
  color: var(--text-primary);
}

.btn-icon:active {
  transform: scale(0.92);
}

.btn-control {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  inline-size: 2.25rem;
  block-size: 2.25rem;
  border-radius: var(--border-radius-full);
  background: transparent;
  color: var(--text-primary);
  border: none;
  cursor: pointer;
  touch-action: manipulation;
  transition: transform var(--transition-fast), background-color var(--transition-fast);
}

.btn-control:active {
  transform: scale(0.9);
}

.btn-primary-play {
  inline-size: 2.75rem;
  block-size: 2.75rem;
  background-color: var(--accent-brand);
  color: #ffffff;
}

.btn-primary-play:hover {
  background-color: var(--accent-brand-hover);
}

.btn-primary-play:active {
  transform: scale(0.92);
}