:root {
    --paper-white:  #fbf9ef;
    --paper-blue:   #c6e0f3;
    --paper-pink:   #fbd1db;
    --paper-yellow: #fcf2c7;
    --paper-green:  #c7e8d4;
    --line:         rgba(45, 90, 140, 0.40);
    --line-soft:    rgba(45, 90, 140, 0.22);
    --ink:          rgba(0, 0, 0, 0.86);
    --ink-soft:     rgba(0, 0, 0, 0.50);
    --ink-faint:    rgba(0, 0, 0, 0.30);
    --bg:           #ecebe6;
    --surface:      #ffffff;
    --shadow-1:     0 1px 2px rgba(0,0,0,0.05), 0 1px 3px rgba(0,0,0,0.05);
    --shadow-2:     0 6px 18px rgba(0,0,0,0.08), 0 1px 4px rgba(0,0,0,0.06);
}

* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "Inter", "Segoe UI", system-ui, sans-serif;
    -webkit-font-smoothing: antialiased;
    background: var(--bg);
    color: var(--ink);
    font-size: 15px;
    line-height: 1.4;
}
button { font: inherit; }

/* ===== App layout ===== */

.app {
    display: flex;
    flex-direction: column;
    height: 100vh;
    height: 100dvh;
}

.app-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 24px;
    background: var(--surface);
    border-bottom: 1px solid rgba(0,0,0,0.07);
    position: sticky;
    top: 0;
    z-index: 5;
    flex-shrink: 0;
}
.app-header h1 {
    margin: 0;
    font-size: 18px;
    font-weight: 800;
    letter-spacing: -0.01em;
}
.icon-btn {
    background: transparent;
    border: 1px solid rgba(0,0,0,0.14);
    color: var(--ink);
    border-radius: 8px;
    padding: 7px 14px;
    cursor: pointer;
    font-size: 13px;
    font-weight: 600;
    transition: background 0.12s, border-color 0.12s;
}
.icon-btn:hover { background: rgba(0,0,0,0.04); border-color: rgba(0,0,0,0.25); }

.app-error {
    color: #a00;
    font-size: 12px;
    padding: 6px 24px;
    background: rgba(180,0,0,0.07);
}

/* ===== Cards grid ===== */

.cards-grid {
    flex: 1;
    overflow-y: auto;
    padding: 24px;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 20px;
    align-content: start;
}

/* ===== The card itself ===== */

.card {
    border-radius: 10px;
    box-shadow: var(--shadow-2);
    padding: 18px 22px 18px;
    background-color: var(--paper-yellow);
    position: relative;
}

.card-slot { position: relative; }
.card-slot.dragging { opacity: 0.45; }

.card-drag-handle {
    position: absolute;
    top: 8px;
    right: 10px;
    color: var(--ink-faint);
    cursor: grab;
    font-size: 13px;
    letter-spacing: -1px;
    user-select: none;
    padding: 2px 4px;
    border-radius: 4px;
    line-height: 1;
    opacity: 0;
    transition: opacity 0.15s;
}
.card:hover .card-drag-handle { opacity: 1; }
.card-drag-handle:hover { background: rgba(0,0,0,0.06); color: var(--ink-soft); }
.card-drag-handle:active { cursor: grabbing; }
@media (max-width: 700px) {
    .card-drag-handle { opacity: 0.5; }   /* always visible on touch */
}
.card.color-white  { background-color: var(--paper-white); }
.card.color-blue   { background-color: var(--paper-blue); }
.card.color-pink   { background-color: var(--paper-pink); }
.card.color-yellow { background-color: var(--paper-yellow); }
.card.color-green  { background-color: var(--paper-green); }

.card-title {
    font-size: 24px;
    font-weight: 800;
    border: none;
    background: transparent;
    width: 100%;
    outline: none;
    color: var(--ink);
    margin: 0 0 6px;
    letter-spacing: -0.01em;
    font-family: inherit;
}
.card-title::placeholder { color: var(--ink-faint); font-weight: 700; }
.card-divider {
    border: none;
    border-top: 1px solid var(--line);
    margin: 0 0 14px;
}

/* ===== Tasks ===== */

.tasks { display: flex; flex-direction: column; }

.task-row {
    display: flex;
    align-items: center;
    gap: 10px;
    height: 32px;
    cursor: text;
    border-bottom: 1px solid var(--line);
}
.task-row .checkbox {
    width: 16px;
    height: 16px;
    border: 1.5px solid rgba(0,0,0,0.4);
    border-radius: 3px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    background: rgba(255,255,255,0.4);
    transition: background 0.1s, border-color 0.1s;
}
.task-row .checkbox:hover { border-color: rgba(0,0,0,0.6); }
.task-row .checkbox.checked {
    background: rgba(0,0,0,0.75);
    border-color: rgba(0,0,0,0.75);
    color: white;
    font-size: 11px;
    font-weight: 800;
}
.task-row input[type="text"] {
    flex: 1;
    border: none;
    background: transparent;
    outline: none;
    font-size: 16px;
    line-height: 1.2;
    color: var(--ink);
    height: 100%;
    padding: 0;
    font-family: inherit;
    min-width: 0;     /* allow shrinking */
}
.task-row input[type="text"]::placeholder { color: var(--ink-faint); }
.task-row.done input[type="text"] {
    text-decoration: line-through;
    color: var(--ink-soft);
}
.task-row .task-remove {
    border: none;
    background: transparent;
    color: var(--ink-faint);
    cursor: pointer;
    opacity: 0;
    width: 22px;
    height: 22px;
    border-radius: 4px;
    font-size: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: opacity 0.1s, background 0.1s, color 0.1s;
    flex-shrink: 0;
}
.task-row .task-remove:hover { background: rgba(0,0,0,0.06); color: var(--ink-soft); }
.task-row:hover .task-remove { opacity: 1; }

.add-task {
    background: transparent;
    border: none;
    color: var(--ink-faint);
    cursor: pointer;
    padding: 0;
    margin-top: 2px;
    font-size: 11px;
    align-self: flex-start;
    line-height: 1.6;
}
.add-task:hover { color: var(--ink-soft); }

/* ===== Card footer (color picker + delete) ===== */

.card-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: 22px;
    padding-top: 16px;
    border-top: 1px solid rgba(0,0,0,0.08);
}
.color-picker { display: flex; gap: 8px; }
.color-swatch {
    width: 24px; height: 24px; border-radius: 50%;
    cursor: pointer;
    border: 1px solid rgba(0,0,0,0.18);
    transition: transform 0.1s;
}
.color-swatch:hover { transform: scale(1.1); }
.color-swatch.selected {
    outline: 2px solid var(--ink);
    outline-offset: 2px;
}
.color-swatch.white  { background: var(--paper-white); }
.color-swatch.blue   { background: var(--paper-blue); }
.color-swatch.pink   { background: var(--paper-pink); }
.color-swatch.yellow { background: var(--paper-yellow); }
.color-swatch.green  { background: var(--paper-green); }

.delete-card {
    background: transparent;
    border: none;
    color: var(--ink-faint);
    cursor: pointer;
    padding: 6px 10px;
    border-radius: 6px;
    font-size: 13px;
}
.delete-card:hover { background: rgba(180,0,0,0.08); color: rgba(180,0,0,0.85); }

/* ===== Empty / login states ===== */

.empty-state {
    margin: auto;
    color: var(--ink-soft);
    text-align: center;
    padding: 40px;
}

.token-prompt {
    margin: auto;
    max-width: 360px;
    padding: 32px;
    background: var(--surface);
    border-radius: 12px;
    box-shadow: var(--shadow-2);
}
.token-prompt h2 { margin: 0 0 8px; font-size: 18px; font-weight: 700; }
.token-prompt p { margin: 0 0 16px; color: var(--ink-soft); font-size: 13px; }
.token-prompt input {
    width: 100%;
    font-size: 16px;
    padding: 10px 12px;
    border: 1px solid rgba(0,0,0,0.18);
    border-radius: 8px;
    outline: none;
    font-family: inherit;
}
.token-prompt input:focus { border-color: var(--ink); }
.token-prompt button {
    margin-top: 12px;
    width: 100%;
    padding: 10px;
    background: var(--ink);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
}
.token-prompt button:hover { opacity: 0.9; }

/* ===== Mobile ===== */

@media (max-width: 700px) {
    .app-header { padding: 12px 16px; }
    .cards-grid {
        padding: 16px;
        gap: 14px;
        grid-template-columns: 1fr;
    }
    .card { padding: 16px 18px; }
    .card-title { font-size: 20px; }
    .task-row { height: 36px; }
    .task-row .checkbox { width: 20px; height: 20px; }
    .task-row .task-remove { opacity: 1; width: 28px; height: 28px; font-size: 18px; }
}