* {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
      -webkit-tap-highlight-color: transparent;
    }

    html, body {
      font-family: var(--font-sans);
      font-size: var(--fs-sm);
      font-weight: var(--fw-medium);
    }

    b, strong {
      font-weight: var(--fw-bold);
    }

    h1, h2, h3 {
      font-family: var(--font-serif);
      font-weight: var(--fw-bold);
      color: var(--text-primary);
      letter-spacing: -0.02em;
    }
    h1 { font-size: var(--fs-xl); line-height: 1.15; }
    h2 { font-size: var(--fs-lg); line-height: 1.2; }
    h3 { font-size: var(--fs-md); line-height: 1.25; }


    button, input, select, textarea, option, optgroup, ::placeholder {
      font-family: var(--font-sans) !important;
      font-weight: var(--fw-medium);
    }

    input, select, textarea {
      background: var(--card-inner);
      border: 1px solid var(--card-border);
      color: var(--text-primary);
      border-radius: 10px;
      font-size: var(--fs-base);
      outline: none;
      transition: border-color 0.15s ease, box-shadow 0.15s ease;
    }

    input:focus, select:focus, textarea:focus {
      border-color: var(--text-accent);
    }

    input::placeholder, textarea::placeholder {
      color: var(--text-secondary);
      opacity: 0.8;
    }

    html {
      width: 100%;
      max-width: 100%;
      overflow-x: hidden;
    }

    body {
      background: var(--bg);
      font-family: var(--font-sans);
      color: var(--text-primary);
      width: 100%;
      max-width: 100%;
      min-height: 100vh;
      overflow-x: hidden;
      position: relative;
      padding-bottom: 96px;
      -webkit-font-smoothing: antialiased;
      font-variant-numeric: tabular-nums;
    }

    /* Master Top Header */
    header.app-top-header {
      position: sticky;
      top: 0;
      padding-top: max(14px, env(safe-area-inset-top, 14px));
      padding-bottom: 12px;
      padding-left: max(20px, env(safe-area-inset-left, 20px));
      padding-right: max(20px, env(safe-area-inset-right, 20px));
      background: var(--header-bg);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border-bottom: 1px solid var(--card-border-subtle);
      display: flex;
      justify-content: space-between;
      align-items: center;
      z-index: 50;
      width: 100%;
    }

    .brand-title {
      font-size: var(--fs-xl);
      font-weight: var(--fw-bold);
      letter-spacing: -0.02em;
      color: var(--text-primary);
    }

    .header-actions {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .header-icon-btn {
      background: none;
      border: none;
      color: var(--text-primary);
      width: 36px;
      height: 36px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
    }

    .avatar-pill {
      width: 34px;
      height: 34px;
      border-radius: 50%;
      background: #FFFFFF;
      border: 1.5px solid var(--text-accent);
      color: var(--text-accent);
      font-weight: var(--fw-bold);
      font-size: var(--fs-base);
      display: flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
    }

    /* Base Viewport Container */
    .view-viewport {
      width: 100%;
      max-width: 480px;
      min-width: 0;
      overflow-x: hidden;
      box-sizing: border-box;
      margin: 0 auto;
      padding: 16px 16px 120px;
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    /* ============================================================== */
    /* UNIVERSAL CANOPY BUTTON DESIGN SYSTEM (CENTRAL STANDARD)        */
    /* ============================================================== */
    button {
      font-family: var(--font-sans);
      -webkit-appearance: none;
      appearance: none;
      border: none;
      outline: none;
      box-sizing: border-box;
      cursor: pointer;
      -webkit-tap-highlight-color: transparent;
    }

    .pill-btn, .hub-tab-btn, .canopy-btn, .btn, .btn-neutral, .btn-secondary, .btn-water {
      font-family: var(--font-sans) !important;
      font-size: var(--fs-sm);
      font-weight: var(--fw-bold);
      border-radius: 10px !important;
      padding: 8px 14px;
      background: var(--card-inner);
      color: var(--text-primary);
      border: 1px solid var(--card-border) !important;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      transition: all 0.15s ease;
      line-height: 1.2;
      box-shadow: 0 1px 3px rgba(0, 0, 0, 0.03);
    }

    .pill-btn:hover, .hub-tab-btn:hover, .canopy-btn:hover, .btn-neutral:hover {
      background: var(--card-bg);
      border-color: var(--text-accent) !important;
    }

    .pill-btn:active, .hub-tab-btn:active, .canopy-btn:active, .btn-neutral:active {
      transform: scale(0.97);
    }

    /* Active states for tabs, layout toggles, and theme selectors */
    .pill-btn.active, .hub-tab-btn.active, .canopy-btn.active, .btn-neutral.active {
      background: var(--btn-accent-bg) !important;
      color: var(--btn-accent-text, #FFFFFF) !important;
      border-color: var(--btn-accent-bg) !important;
      box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2) !important;
    }

    .btn-accent {
      background: var(--btn-accent-bg) !important;
      color: var(--btn-accent-text, #FFFFFF) !important;
      border: 1px solid var(--btn-accent-bg) !important;
      border-radius: 10px !important;
    }

    /* Danger / Action Pill Buttons (Remove Friend, Decline, Delete) */
    button[onclick*="handleRemoveFriend"], 
    button[onclick*="handleDeclineFriend"], 
    button[onclick*="handleDelete"], 
    .btn-danger-sm {
      background: rgba(239, 68, 68, 0.08) !important;
      color: #f87171 !important;
      border: 1px solid rgba(239, 68, 68, 0.25) !important;
      border-radius: 8px !important;
      font-weight: var(--fw-bold) !important;
      padding: 4px 10px !important;
      font-size: var(--fs-xs) !important;
    }