/* Exam attempt shell: layout, timer, question navigation and flag button. */
@layer components {
  @keyframes timer-pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.6; }
  }

  .student-attempt {
    background: oklch(var(--oklch-canvas));
    display: flex;
    flex-direction: column;
    min-block-size: 100dvh;
  }
  .student-attempt-header {
    background: oklch(var(--oklch-canvas-raised));
    border-block-end: 2px solid oklch(var(--oklch-border));
    inset-block-start: 0;
    position: sticky;
    z-index: 10;
  }
  .student-attempt-header-inner {
    align-items: center;
    display: flex;
    gap: var(--space-5);
    justify-content: flex-end;
    margin-inline: auto;
    max-inline-size: 100%;
    padding-block: var(--space-5);
    padding-inline: var(--space-5) 180px;
    position: relative;
  }
  .student-attempt-title {
    color: oklch(var(--oklch-ink-darkest));
    flex: 1;
    font-size: 1.25rem;
    font-weight: 700;
    margin-inline-end: auto;
    min-inline-size: 0;
  }

  /* Timer and pause button, pinned to the header's inline end */
  .student-attempt-timer-group {
    align-items: center;
    display: flex;
    flex-shrink: 0;
    gap: 0.5rem;
    inset-block-start: 50%;
    inset-inline-end: var(--space-5);
    position: absolute;
    transform: translateY(-50%);
    z-index: 2;
  }
  .student-pause-btn { white-space: nowrap; }

  .student-attempt-progress-bar {
    background: oklch(var(--oklch-border));
    block-size: 6px;
  }
  .student-attempt-progress-fill {
    background: linear-gradient(90deg, oklch(var(--oklch-primary)), oklch(var(--oklch-primary) / 0.8));
    block-size: 100%;
    inline-size: 100%;
    transform: scaleX(var(--progress, 0));
    transform-origin: left;
    transition: transform 400ms cubic-bezier(0.4, 0, 0.2, 1);
  }

  /* Timer. Variants only set the --timer-* properties. */
  .student-attempt-timer {
    --timer-background: oklch(var(--oklch-canvas-sunken));
    --timer-color: oklch(var(--oklch-ink-mid));

    align-items: center;
    background: var(--timer-background);
    border-radius: var(--radius-full);
    color: var(--timer-color);
    display: flex;
    flex-shrink: 0;
    font-size: 0.9375rem;
    font-weight: 700;
    gap: 0.5rem;
    padding: 0.375rem 0.875rem;
    transition: background 300ms ease, color 300ms ease;
    white-space: nowrap;
  }
  .student-attempt-timer--warning {
    --timer-background: light-dark(oklch(93% 0.06 80), var(--color-warning-surface));
    --timer-color: light-dark(oklch(45% 0.12 55), var(--color-warning-text));
  }
  .student-attempt-timer--critical {
    --timer-background: light-dark(oklch(92% 0.08 20), var(--color-danger-surface));
    --timer-color: light-dark(oklch(40% 0.18 20), var(--color-danger-text));

    animation: timer-pulse 1s ease-in-out infinite;
  }

  /* Question navigation buttons. States only set the --nav-btn-* properties. */
  .student-question-nav {
    border-block-end: 1px solid oklch(var(--oklch-border));
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    padding: var(--space-4) var(--space-5);
  }
  .student-question-nav-btn {
    --nav-btn-background: oklch(var(--oklch-canvas));
    --nav-btn-border-color: oklch(var(--oklch-border));
    --nav-btn-color: oklch(var(--oklch-ink-mid));
    --nav-btn-shadow: none;

    align-items: center;
    background: var(--nav-btn-background);
    block-size: 2.5rem;
    border: 1.5px solid var(--nav-btn-border-color);
    border-radius: var(--radius-md);
    box-shadow: var(--nav-btn-shadow);
    color: var(--nav-btn-color);
    cursor: pointer;
    display: flex;
    font-size: 0.8125rem;
    font-weight: 700;
    inline-size: 2.5rem;
    justify-content: center;
    padding: 0;
    transition: all 150ms ease;

    &:hover {
      --nav-btn-background: oklch(var(--oklch-canvas-raised));
      --nav-btn-border-color: oklch(var(--oklch-primary));
      --nav-btn-color: oklch(var(--oklch-primary));
    }
    &.answered {
      --nav-btn-background: light-dark(oklch(94% 0.06 252), var(--color-primary-tint));
      --nav-btn-border-color: oklch(var(--oklch-primary));
      --nav-btn-color: oklch(var(--oklch-primary));
    }
    &.current {
      --nav-btn-background: oklch(var(--oklch-primary));
      --nav-btn-border-color: oklch(var(--oklch-primary));
      --nav-btn-color: oklch(99% 0 0);
      --nav-btn-shadow: 0 0 0 3px oklch(var(--oklch-primary) / 0.2);
    }
    &.saved {
      --nav-btn-background: oklch(55% 0.16 150);
      --nav-btn-border-color: oklch(45% 0.16 150);
      --nav-btn-color: oklch(99% 0 0);
      --nav-btn-shadow: 0 0 0 3px oklch(55% 0.16 150 / 0.3);
    }
    &.flagged {
      position: relative;

      &::after {
        background: oklch(60% 0.19 30);
        block-size: 0.5rem;
        border: 1.5px solid oklch(var(--oklch-canvas));
        border-radius: 50%;
        content: "";
        inline-size: 0.5rem;
        inset-block-start: -3px;
        inset-inline-end: -3px;
        position: absolute;
      }
      .student-question-nav-flag {
        display: inline;
        margin-inline-end: 0.25rem;
      }
    }
  }
  .student-question-nav-flag { display: none; }

  /* In-exam question flag button. States only set the --flag-btn-* properties. */
  .question-flag-btn {
    --flag-btn-background: oklch(var(--oklch-canvas));
    --flag-btn-border-color: oklch(var(--oklch-border));
    --flag-btn-color: oklch(var(--oklch-ink-mid));

    align-items: center;
    background: var(--flag-btn-background);
    block-size: 2rem;
    border: 1.5px solid var(--flag-btn-border-color);
    border-radius: var(--radius-md);
    box-sizing: border-box;
    color: var(--flag-btn-color);
    cursor: pointer;
    display: inline-flex;
    font-size: 0.75rem;
    font-weight: 600;
    gap: 0.25rem;
    padding: 0 0.625rem;
    transition: all 150ms ease;

    &:hover {
      --flag-btn-border-color: oklch(60% 0.19 30);
      --flag-btn-color: light-dark(oklch(50% 0.19 30), oklch(75% 0.14 30));
    }
    &:disabled {
      cursor: not-allowed;
      opacity: 0.5;
    }
  }
  .question-flag-btn--active {
    --flag-btn-background: var(--flag-surface);
    --flag-btn-border-color: oklch(60% 0.19 30);
    --flag-btn-color: var(--flag-text);
  }

  /* In-exam per-question flag badge (static indicator, toggled via the Flag button) */
  .question-flag-badge {
    align-items: center;
    background: var(--flag-surface);
    border-radius: var(--radius-full);
    color: var(--flag-text);
    display: inline-flex;
    font-size: 0.75rem;
    font-weight: 600;
    gap: 0.25rem;
    padding: 0.15rem 0.5rem;
  }
  .question-flag-btn--active,
  .question-flag-badge {
    --flag-surface: light-dark(oklch(93% 0.08 30), oklch(0.30 0.07 30));
    --flag-text: light-dark(oklch(45% 0.19 30), oklch(0.82 0.12 30));
  }
}