/* Solvable components. Every colour, size and radius comes from tokens.css. */

.sv-icon { display: inline-block; flex: none; vertical-align: -0.2em; }

/* Logo */
.sv-logo { display: block; flex: none; }
.sv-logo-box { stroke: var(--ink); }
.sv-logo-tick { stroke: var(--pen); }
.sv-logo-swipe { fill: var(--highlight); }
.sv-logo-word { fill: var(--ink); }
.sv-logo-able { fill: var(--on-highlight); }

/* Button */
.sv-btn {
  display: inline-flex; align-items: center; gap: var(--space-2);
  min-height: 44px; padding: 0 var(--space-6);
  border-radius: var(--radius-md); border: 2px solid transparent;
  font-family: var(--font-display); font-weight: 600; font-size: 16px; line-height: 1;
  text-decoration: none; cursor: pointer; transition: transform .12s ease, background-color .12s ease;
}
.sv-btn:focus-visible { outline: 2px solid var(--pen); outline-offset: 2px; }
.sv-btn:active { transform: translateY(1px); }
.sv-btn[disabled] { cursor: not-allowed; opacity: .5; }
.sv-btn--primary { background: var(--pen); color: var(--on-pen); }
.sv-btn--primary:hover { box-shadow: 3px 3px 0 var(--ink); transform: translate(-1px, -1px); }
.sv-btn--secondary { background: transparent; color: var(--ink); border-color: var(--ink); }
.sv-btn--secondary:hover { background: var(--pen-soft); }
.sv-btn--quiet { background: transparent; color: var(--pen); padding: 0 var(--space-1); text-decoration: underline; text-underline-offset: 4px; text-decoration-thickness: 1.5px; }
@media (prefers-reduced-motion: reduce) { .sv-btn { transition: none; } .sv-btn--primary:hover, .sv-btn:active { transform: none; } }

/* Highlight: a marker swipe, slightly uneven */
.sv-highlight {
  color: var(--on-highlight); background: transparent; padding: 0 .12em; margin: 0 -.06em;
  background-image: linear-gradient(176deg, transparent 8%, var(--highlight) 9%, var(--highlight) 88%, transparent 89%);
  border-radius: var(--radius-sm); box-decoration-break: clone; -webkit-box-decoration-break: clone;
}

/* Label */
.sv-label {
  display: inline-flex; align-items: center; gap: var(--space-1);
  font-family: var(--font-mono); font-size: 12px; line-height: 16px; font-weight: 500;
  letter-spacing: .08em; text-transform: uppercase;
}
.sv-label--muted { color: var(--ink-muted); }
.sv-label--pen { color: var(--pen); }
.sv-label--solved { color: var(--solved); }

/* Margin note */
.sv-note {
  display: inline-flex; align-items: flex-start; gap: var(--space-1);
  font-family: var(--font-hand); font-size: 22px; line-height: 26px; font-weight: 500; color: var(--pen);
}
.sv-note-arrow { margin-top: 10px; }
.sv-note--right .sv-note-arrow { transform: scaleX(-1); }
.sv-note--right { flex-direction: row-reverse; }

/* Graph paper band */
.sv-graph {
  background-color: var(--paper);
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: var(--grid-cell) var(--grid-cell);
  background-position: -1px -1px;
}

/* Session card */
.sv-session {
  display: flex; flex-direction: column; gap: var(--space-2);
  padding: var(--space-6); background: var(--paper-raised); color: var(--ink);
  border: 1.5px solid var(--grid); border-radius: var(--radius-md);
}
.sv-session--next { background: var(--pen-soft); border-color: var(--pen); }
.sv-session--done { background: var(--paper); }
.sv-session-top { display: flex; align-items: center; justify-content: space-between; gap: var(--space-2); flex-wrap: wrap; }
.sv-session-done { display: inline-flex; align-items: center; gap: var(--space-1); color: var(--solved); font-family: var(--font-mono); font-size: 12px; font-weight: 500; letter-spacing: .08em; text-transform: uppercase; }
.sv-session-next { font-family: var(--font-hand); font-size: 22px; line-height: 1; color: var(--pen); transform: rotate(-3deg); }
.sv-session-title { margin: 0; font-family: var(--font-display); font-size: 22px; line-height: 28px; font-weight: 600; text-wrap: balance; }
.sv-session--done .sv-session-title { color: var(--ink-muted); }
.sv-session-reading, .sv-session-meta { margin: 0; font-family: var(--font-serif); font-size: 15px; line-height: 24px; color: var(--ink-muted); display: flex; gap: var(--space-4); flex-wrap: wrap; }
.sv-session-reading { gap: var(--space-2); color: var(--ink); flex-wrap: nowrap; }
.sv-session-meta span, .sv-session-reading { align-items: baseline; }
.sv-session-meta span { display: inline-flex; gap: var(--space-1); align-items: center; }
.sv-session-reading .sv-icon { margin-top: 4px; }
.sv-session-cta { margin-top: var(--space-2); }

/* Stat line */
.sv-stat { margin: 0; display: flex; flex-direction: column; gap: var(--space-2); }
.sv-stat-figures { display: flex; align-items: center; gap: var(--space-4); flex-wrap: wrap; font-family: var(--font-mono); font-size: 32px; line-height: 40px; color: var(--ink); font-variant-numeric: tabular-nums; }
.sv-stat-figures .sv-icon { color: var(--ink-muted); }
.sv-stat-caption { font-family: var(--font-serif); font-size: 15px; line-height: 24px; color: var(--ink-muted); max-width: 46ch; }
.sv-stat-source { font-family: var(--font-mono); font-size: 12px; letter-spacing: .04em; }

/* FAQ */
.sv-faq { border-top: 1.5px solid var(--grid); color: var(--ink); }
.sv-faq:last-child { border-bottom: 1.5px solid var(--grid); }
.sv-faq summary {
  list-style: none; cursor: pointer; display: flex; justify-content: space-between; align-items: center; gap: var(--space-4);
  padding: var(--space-4) 0; font-family: var(--font-display); font-size: 18px; line-height: 24px; font-weight: 600;
}
.sv-faq summary::-webkit-details-marker { display: none; }
.sv-faq summary:focus-visible { outline: 2px solid var(--pen); outline-offset: 2px; }
.sv-faq-icon { color: var(--pen); transition: transform .15s ease; }
.sv-faq[open] .sv-faq-icon { transform: rotate(45deg); }
.sv-faq-answer { padding: 0 0 var(--space-4); font-family: var(--font-serif); font-size: 15px; line-height: 24px; color: var(--ink); max-width: 60ch; }
.sv-faq-answer p { margin: 0 0 var(--space-2); }

/* Sign-up form */
.sv-form { display: flex; flex-direction: column; gap: var(--space-4); padding: var(--space-6); background: var(--paper-raised); border: 1.5px solid var(--grid); border-radius: var(--radius-md); color: var(--ink); max-width: 480px; }
.sv-field { display: flex; flex-direction: column; gap: var(--space-1); }
.sv-field label { font-family: var(--font-mono); font-size: 12px; line-height: 16px; font-weight: 500; letter-spacing: .08em; text-transform: uppercase; color: var(--ink-muted); }
.sv-field input {
  min-height: 44px; padding: 0 var(--space-4); border: 1.5px solid var(--ink-muted); border-radius: var(--radius-md);
  background: var(--paper); color: var(--ink); font-family: var(--font-serif); font-size: 16px;
}
.sv-field input::placeholder { color: var(--ink-muted); opacity: .8; }
.sv-field input:focus-visible { outline: 2px solid var(--pen); outline-offset: 2px; border-color: var(--pen); }
.sv-form-help { margin: 0; font-family: var(--font-serif); font-size: 14px; line-height: 20px; color: var(--ink-muted); }
.sv-form-error { margin: 0; font-family: var(--font-serif); font-size: 15px; line-height: 22px; color: var(--ink); padding-left: var(--space-2); border-left: 3px solid var(--pen); }
.sv-form .sv-btn { align-self: flex-start; }
.sv-form--done { flex-direction: row; align-items: flex-start; gap: var(--space-4); }
.sv-form-tick { display: inline-flex; align-items: center; justify-content: center; width: 40px; height: 40px; border: 2px solid var(--solved); border-radius: var(--radius-md); color: var(--solved); flex: none; }
.sv-form-done-title { margin: 0 0 var(--space-1); font-family: var(--font-display); font-size: 20px; font-weight: 600; }

/* Site header */
.sv-header { display: flex; align-items: center; justify-content: space-between; gap: var(--space-4); flex-wrap: wrap; padding: var(--space-4) 0; color: var(--ink); }
.sv-header-home { display: inline-flex; border-radius: var(--radius-sm); }
.sv-header-home:focus-visible { outline: 2px solid var(--pen); outline-offset: 4px; }
.sv-header-nav { display: flex; align-items: center; gap: var(--space-6); flex-wrap: wrap; }
.sv-header-nav > a:not(.sv-btn) { color: var(--ink); font-family: var(--font-display); font-weight: 600; font-size: 15px; text-decoration: none; }
.sv-header-nav > a:not(.sv-btn):hover { text-decoration: underline; text-decoration-color: var(--highlight); text-decoration-thickness: 6px; text-underline-offset: -2px; text-decoration-skip-ink: none; }
.sv-header-nav > a:not(.sv-btn):focus-visible { outline: 2px solid var(--pen); outline-offset: 2px; }