/* ==========================================================================
   ROOM-Acoustics Web - Global Design System & Variables
   Modern Material Design with iOS Theme Parity
   ========================================================================== */

:root {
  /* Brand Colors */
  --color-primary: #007AFF;
  --color-primary-hover: #0062cc;
  --color-primary-light: rgba(0, 122, 255, 0.12);
  --color-secondary: #5856D6;
  --color-accent: #34C759;
  
  /* Status Colors */
  --color-success: #34C759;
  --color-warning: #FF9500;
  --color-danger: #FF3B30;
  --color-info: #5AC8FA;

  /* Acoustic Specific Colors */
  --color-axial: #007AFF;
  --color-tangential: #AF52DE;
  --color-oblique: #FF9500;
  --color-target: #34C759;

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: "SF Mono", Menlo, Monaco, Consolas, "Courier New", monospace;
  
  /* Spacing */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;

  /* Radii */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s ease;
}

/* Light Theme (Default) */
[data-theme="light"], :root {
  --color-bg: #F2F2F7;
  --color-surface: #FFFFFF;
  --color-surface-elevated: #FFFFFF;
  --color-surface-secondary: #F8F9FA;
  --color-surface-tertiary: #E5E5EA;
  --color-border: rgba(60, 60, 67, 0.14);
  --color-border-subtle: rgba(60, 60, 67, 0.08);
  
  --color-text-primary: #1C1C1E;
  --color-text-secondary: #8E8E93;
  --color-text-tertiary: #AEAEB2;
  --color-text-inverse: #FFFFFF;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.12);
  --shadow-glow: 0 0 16px rgba(0, 122, 255, 0.25);
}

/* Dark Theme */
[data-theme="dark"] {
  --color-bg: #000000;
  --color-surface: #1C1C1E;
  --color-surface-elevated: #2C2C2E;
  --color-surface-secondary: #2C2C2E;
  --color-surface-tertiary: #3A3A3C;
  --color-border: rgba(255, 255, 255, 0.14);
  --color-border-subtle: rgba(255, 255, 255, 0.08);

  --color-text-primary: #FFFFFF;
  --color-text-secondary: #8E8E93;
  --color-text-tertiary: #636366;
  --color-text-inverse: #1C1C1E;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 10px 36px rgba(0, 0, 0, 0.5);
  --shadow-glow: 0 0 20px rgba(0, 122, 255, 0.4);
}

/* Base Reset */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

html, body {
  width: 100%;
  height: 100%;
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text-primary);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  user-select: none;
}

#app {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  position: relative;
}

/* Global Header Bar */
.app-header {
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-md) var(--space-lg);
  background: var(--color-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border-subtle);
  transition: background var(--transition-normal);
}

.header-left, .header-right {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.header-title {
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.header-title .title-badge {
  font-size: 0.7rem;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  background: var(--color-primary-light);
  color: var(--color-primary);
  text-transform: uppercase;
}

/* Header Language Selector Dropdown */
.header-lang-wrapper {
  position: relative;
  display: inline-flex;
  align-items: center;
  background: var(--color-surface);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-full);
  padding: 4px 10px 4px 8px;
  transition: all var(--transition-fast);
  box-shadow: var(--shadow-sm);
}

.header-lang-wrapper:hover {
  border-color: var(--color-primary);
  background: var(--color-surface-elevated);
}

.header-lang-icon {
  font-size: 0.95rem;
  margin-right: 4px;
  user-select: none;
  pointer-events: none;
}

.header-lang-select {
  appearance: none;
  -webkit-appearance: none;
  background: transparent;
  border: none;
  outline: none;
  color: var(--color-text-primary);
  font-family: var(--font-sans);
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  padding-right: 14px;
  background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%238E8E93' stroke-width='2.5' stroke-linecap='round' stroke-linejoin='round'%3e%3cpolyline points='6 9 12 15 18 9'%3e%3c/polyline%3e%3c/svg%3e");
  background-repeat: no-repeat;
  background-position: right center;
  background-size: 10px;
}

.header-lang-select option {
  background-color: var(--color-surface-elevated);
  color: var(--color-text-primary);
  font-size: 0.9rem;
}

@media (max-width: 520px) {
  .header-lang-wrapper {
    padding: 3px 6px 3px 6px;
  }
  .header-lang-select {
    font-size: 0.76rem;
    max-width: 90px;
  }
  .header-title span:first-child {
    font-size: 1.1rem;
  }
}


/* View Container */
.main-content {
  flex: 1;
  padding: var(--space-md) var(--space-lg) var(--space-xl);
  overflow-y: auto;
}

/* Utility classes */
.flex { display: flex; }
.flex-col { display: flex; flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.gap-lg { gap: var(--space-lg); }
.text-center { text-align: center; }
.text-muted { color: var(--color-text-secondary); }
.font-mono { font-family: var(--font-mono); }