:root {
    --bg: #0a0a0a;
    --surface: #111111;
    --surface2: #1a1a1a;
    --border: #222;
    --accent: #c8f560;
    --accent2: #60c8f5;
    --accent3: #f560c8;
    --text: #e8e8e8;
    --muted: #666;
    --danger: #f56060;
    --mono: "DM Mono", monospace;
    --sans: "Syne", sans-serif;
}
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body {
    background: var(--bg);
    color: var(--text);
    font-family: var(--sans);
    min-height: 100vh;
}

/* AUTH */
#auth-screen {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: radial-gradient(ellipse at 30% 50%, #0f1f0a 0%, var(--bg) 60%);
}
.auth-box {
    width: 380px;
    padding: 48px 40px;
    border: 1px solid var(--border);
    background: var(--surface);
}
.auth-box h1 {
    font-size: 2.4rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    color: var(--accent);
    margin-bottom: 8px;
}
.auth-box p {
    color: var(--muted);
    font-size: 0.85rem;
    margin-bottom: 32px;
    font-family: var(--mono);
}
.auth-tabs {
    display: flex;
    gap: 0;
    margin-bottom: 28px;
    border: 1px solid var(--border);
}
.auth-tab {
    flex: 1;
    padding: 10px;
    text-align: center;
    cursor: pointer;
    font-family: var(--mono);
    font-size: 0.8rem;
    color: var(--muted);
    transition: all 0.15s;
}
.auth-tab.active {
    background: var(--accent);
    color: var(--bg);
    font-weight: 500;
}

/* INPUTS */
input,
textarea,
select {
    width: 100%;
    padding: 10px 12px;
    background: var(--bg);
    border: 1px solid var(--border);
    color: var(--text);
    font-family: var(--mono);
    font-size: 0.85rem;
    outline: none;
    transition: border 0.15s;
    border-radius: 4px;
}
input:focus,
textarea:focus,
select:focus {
    border-color: var(--accent);
}
label {
    display: block;
    font-size: 0.7rem;
    font-family: var(--mono);
    color: var(--muted);
    margin-bottom: 4px;
    text-transform: uppercase;
    letter-spacing: 0.08em;
}
.field {
    margin-bottom: 16px;
}
textarea {
    resize: vertical;
    min-height: 80px;
}
select option {
    background: var(--surface2);
}

/* BUTTONS */
.btn {
    padding: 10px 20px;
    border: none;
    cursor: pointer;
    font-family: var(--mono);
    font-size: 0.82rem;
    font-weight: 500;
    transition: all 0.15s;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    border-radius: 4px;
}
.btn-primary {
    background: var(--accent);
    color: var(--bg);
}
.btn-primary:hover {
    background: #d4ff66;
}
.btn-secondary {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text);
}
.btn-secondary:hover {
    border-color: var(--accent);
    color: var(--accent);
}
.btn-danger {
    background: transparent;
    border: 1px solid var(--danger);
    color: var(--danger);
}
.btn-danger:hover {
    background: var(--danger);
    color: white;
}
.btn-sm {
    padding: 6px 12px;
    font-size: 0.75rem;
}
.btn-full {
    width: 100%;
    justify-content: center;
    padding: 13px;
}
.btn-icon {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--muted);
    font-size: 1rem;
    padding: 2px 6px;
}
.btn-icon:hover {
    color: var(--danger);
}

/* LAYOUT */
#app {
    display: none;
}
.topbar {
    position: sticky;
    top: 0;
    z-index: 100;
    height: 52px;
    border-bottom: 1px solid var(--border);
    background: var(--bg);
    display: flex;
    align-items: center;
    padding: 0 24px;
    gap: 0;
}
.topbar-brand {
    font-weight: 800;
    font-size: 1.1rem;
    color: var(--accent);
    letter-spacing: -0.02em;
    margin-right: 16px;
}
.nav-items {
    display: flex;
    flex: 1;
    gap: 4px;
    align-items: center;
    margin-left: auto;
}
.mobile-nav-toggle {
    display: none;
    cursor: pointer;
    padding: 8px;
    font-size: 1.2rem;
}
.topbar-brand { margin-right: 16px; }
.nav-item {
    padding: 0 12px;
    height: 52px;
    display: flex;
    align-items: center;
    cursor: pointer;
    font-size: 0.8rem;
    font-family: var(--mono);
    color: var(--muted);
    border-bottom: 2px solid transparent;
    transition: all 0.15s;
    white-space: nowrap;
}
.nav-item:hover {
    color: var(--text);
}
.nav-item.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
}
.topbar-right {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-left: auto;
}
.user-chip {
    font-family: var(--mono);
    font-size: 0.75rem;
    color: var(--muted);
}

.page {
    display: none;
    padding: 32px 28px;
    max-width: 1100px;
    margin: 0 auto;
}
.page.active {
    display: block;
}

.page-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 28px;
    flex-wrap: wrap;
    gap: 12px;
}
.page-title {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.03em;
}
.page-title span {
    color: var(--accent);
}

/* CARDS */
.card {
    background: var(--surface);
    border: 1px solid var(--border);
    padding: 20px;
    margin-bottom: 12px;
}
.card-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    margin-bottom: 12px;
}
.card-title {
    font-weight: 600;
    font-size: 0.95rem;
}
.card-meta {
    font-family: var(--mono);
    font-size: 0.72rem;
    color: var(--muted);
    margin-top: 2px;
}
.card-actions {
    display: flex;
    gap: 6px;
}
.tag {
    display: inline-flex;
    padding: 2px 8px;
    font-size: 0.68rem;
    font-family: var(--mono);
    border: 1px solid;
    margin-right: 4px;
    margin-bottom: 4px;
}
.tag-green {
    border-color: var(--accent);
    color: var(--accent);
}
.tag-blue {
    border-color: var(--accent2);
    color: var(--accent2);
}
.tag-pink {
    border-color: var(--accent3);
    color: var(--accent3);
}
.tag-gray {
    border-color: var(--muted);
    color: var(--muted);
}

/* STATS GRID */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 12px;
    margin-bottom: 28px;
}
.stat-card {
    background: var(--surface);
    border: 1px solid var(--border);
    padding: 16px 18px;
}
.stat-label {
    font-family: var(--mono);
    font-size: 0.68rem;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 6px;
}
.stat-value {
    font-size: 1.6rem;
    font-weight: 700;
    letter-spacing: -0.03em;
}
.stat-unit {
    font-size: 0.75rem;
    color: var(--muted);
    font-family: var(--mono);
    margin-left: 3px;
}

/* CALORIES WIDGET */
.cal-widget {
    background: var(--surface);
    border: 1px solid var(--accent);
    padding: 24px;
    margin-bottom: 28px;
}
.cal-main {
    font-size: 3rem;
    font-weight: 800;
    color: var(--accent);
    letter-spacing: -0.04em;
}
.cal-label {
    font-family: var(--mono);
    font-size: 0.75rem;
    color: var(--muted);
    margin-bottom: 4px;
}
.cal-breakdown {
    display: flex;
    gap: 24px;
    margin-top: 12px;
    font-family: var(--mono);
    font-size: 0.78rem;
    color: var(--muted);
}
.cal-breakdown span b {
    color: var(--text);
}

/* MODAL */
.modal-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.75);
    z-index: 200;
    align-items: center;
    justify-content: center;
    padding: 16px;
}
.modal-overlay.open {
    display: flex;
}
.modal {
    background: var(--surface);
    border: 1px solid var(--border);
    width: 560px;
    max-width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    border-radius: 8px;
}
.modal-header {
    padding: 20px 24px 16px;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.modal-title {
    font-weight: 700;
    font-size: 1rem;
}
.modal-close {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--muted);
    font-size: 1.4rem;
    line-height: 1;
    padding: 0;
}
.modal-close:hover {
    color: var(--text);
}
.modal-body {
    padding: 24px;
}
.modal-footer {
    padding: 16px 24px;
    border-top: 1px solid var(--border);
    display: flex;
    gap: 8px;
    justify-content: flex-end;
    flex-wrap: wrap;
}

/* EXERCISES LIST in plan editor */
.exercise-list {
    margin-bottom: 12px;
}
.exercise-row {
    background: var(--bg);
    border: 1px solid var(--border);
    padding: 12px;
    margin-bottom: 8px;
    border-radius: 4px;
}
.exercise-row-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
}
.exercise-fields {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 8px;
}

/* SETS LOG */
.sets-table {
    width: 100%;
    border-collapse: collapse;
    font-family: var(--mono);
    font-size: 0.78rem;
    margin: 8px 0;
}
.sets-table th {
    text-align: left;
    color: var(--muted);
    font-weight: 400;
    padding: 4px 8px 8px 0;
}
.sets-table td {
    padding: 4px 8px 4px 0;
    border-bottom: 1px solid var(--border);
}
.sets-table input {
    padding: 4px 6px;
    font-size: 0.78rem;
}

.exercise-accordion {
    border: 1px solid var(--border);
    margin-bottom: 8px;
    border-radius: 4px;
    overflow: hidden;
}
.exercise-accordion-header {
    padding: 12px 16px;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--bg);
}
.exercise-accordion-header:hover {
    background: var(--surface2);
}
.exercise-accordion-header .ex-name {
    font-weight: 600;
}
.exercise-accordion-header .ex-meta {
    font-family: var(--mono);
    font-size: 0.72rem;
    color: var(--muted);
}
.exercise-accordion-body {
    padding: 12px 16px;
    display: none;
    background: var(--surface);
}
.exercise-accordion.open .exercise-accordion-body {
    display: block;
}
.exercise-accordion.logged .exercise-accordion-header {
    opacity: 0.5;
}
.exercise-accordion.logged .exercise-accordion-header::after {
    content: " ✓ logged";
    color: var(--accent);
    font-size: 0.7rem;
}

/* LOG ENTRIES */
.log-entry {
    background: var(--surface);
    border-left: 2px solid var(--border);
    padding: 12px 16px;
    margin-bottom: 8px;
}
.log-entry.workout {
    border-left-color: var(--accent);
}
.log-entry.diet {
    border-left-color: var(--accent2);
}
.log-date {
    font-family: var(--mono);
    font-size: 0.7rem;
    color: var(--muted);
    margin-bottom: 4px;
}
.log-name {
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: 4px;
}
.log-detail {
    font-family: var(--mono);
    font-size: 0.75rem;
    color: var(--muted);
}

/* JSON PASTE AREA */
.paste-hint {
    font-family: var(--mono);
    font-size: 0.72rem;
    color: var(--muted);
    margin-bottom: 8px;
}
.paste-hint code {
    background: var(--bg);
    padding: 1px 5px;
    border: 1px solid var(--border);
    font-size: 0.7rem;
}

/* TABS */
.tabs {
    display: flex;
    border-bottom: 1px solid var(--border);
    margin-bottom: 24px;
    overflow-x: auto;
}
.tab {
    padding: 10px 16px;
    cursor: pointer;
    font-size: 0.8rem;
    font-family: var(--mono);
    color: var(--muted);
    border-bottom: 2px solid transparent;
    margin-bottom: -1px;
    transition: all 0.15s;
    white-space: nowrap;
}
.tab.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
}

/* EMPTY STATE */
.empty {
    text-align: center;
    padding: 48px;
    color: var(--muted);
    font-family: var(--mono);
    font-size: 0.82rem;
    grid-column: 1 / -1;
}
.empty .icon {
    font-size: 2rem;
    margin-bottom: 12px;
    opacity: 0.4;
}

/* HISTORY LOG */
.history-log {
    background: var(--bg);
    border: 1px solid var(--border);
    padding: 16px;
    font-family: var(--mono);
    font-size: 0.75rem;
    max-height: 300px;
    overflow-y: auto;
    color: var(--muted);
}
.history-log .entry {
    padding: 6px 0;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 8px;
}
.history-log .entry:last-child {
    border-bottom: none;
}
.history-log .ts {
    color: var(--accent);
    margin-right: 8px;
}
.history-log .entry-data {
    display: flex;
    align-items: center;
    gap: 4px;
}

/* EXPORT */
.export-box {
    background: var(--bg);
    border: 1px solid var(--border);
    padding: 20px;
}
.export-box pre {
    font-family: var(--mono);
    font-size: 0.72rem;
    color: var(--muted);
    white-space: pre-wrap;
    max-height: 400px;
    overflow-y: auto;
}

/* TOAST */
#toast {
    position: fixed;
    bottom: 24px;
    right: 24px;
    z-index: 999;
    max-width: calc(100vw - 32px);
}
.toast-msg {
    background: var(--surface);
    border: 1px solid var(--border);
    padding: 12px 18px;
    font-family: var(--mono);
    font-size: 0.8rem;
    margin-top: 8px;
    animation: slideIn 0.2s ease;
    border-radius: 4px;
}
.toast-msg.success {
    border-left: 3px solid var(--accent);
}
.toast-msg.error {
    border-left: 3px solid var(--danger);
}
@keyframes slideIn {
    from {
        transform: translateX(20px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* UTILITIES */
.two-col {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}
input[type="checkbox"] {
    width: auto;
    margin-right: 6px;
    accent-color: var(--accent);
}
.checkbox-row {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 8px;
}
.checkbox-row label {
    margin-bottom: 0;
}
hr {
    border: none;
    border-top: 1px solid var(--border);
    margin: 20px 0;
}

/* ============ RESPONSIVE ============ */
@media (max-width: 768px) {
    .topbar {
        padding: 8px 12px;
        flex-wrap: wrap;
        height: auto;
        min-height: 52px;
    }
    .mobile-nav-toggle {
        display: block;
    }
    .topbar-brand {
        font-size: 1rem;
    }
    .topbar-right {
        display: flex;
        align-items: center;
        gap: 8px;
    }
    .topbar-right .user-chip {
        max-width: 100px;
        overflow: hidden;
        text-overflow: ellipsis;
        white-space: nowrap;
    }
    .nav-items {
        display: none;
        order: 3;
        flex-basis: 100%;
        width: 100%;
        margin-top: 0;
        padding-top: 12px;
        padding-bottom: 4px;
        border-top: 1px solid var(--border);
    }
    .nav-items.open {
        display: flex;
        flex-wrap: wrap;
        flex-basis: 100%;
    }
    .topbar-brand {
        order: 1;
    }
    .topbar-right {
        order: 2;
        margin-left: auto;
    }
    .mobile-nav-toggle {
        order: 0;
    }
    .nav-item {
        padding: 10px 12px;
        height: 44px;
        flex: 1 1 auto;
        min-width: 70px;
        justify-content: center;
        text-align: center;
    }
}

    .page {
        padding: 20px 16px;
    }
    .page-header {
        flex-direction: row;
        align-items: center;
        justify-content: space-between;
    }
    .page-title {
        font-size: 1.3rem;
    }
    .empty {
        text-align: center;
        padding: 32px 16px;
    }

    .auth-box {
        width: 100%;
        max-width: 380px;
        padding: 32px 24px;
        margin: 16px;
    }
    .auth-box h1 {
        font-size: 1.8rem;
    }

    .stats-grid {
        grid-template-columns: 1fr 1fr;
        gap: 8px;
    }
    .stat-card {
        padding: 12px 14px;
    }
    .stat-value {
        font-size: 1.3rem;
    }

    .cal-widget {
        padding: 16px;
    }
    .cal-main {
        font-size: 2rem;
    }
    .cal-breakdown {
        flex-wrap: wrap;
        gap: 12px;
    }

    .exercise-fields {
        grid-template-columns: 1fr;
    }
    .two-col {
        grid-template-columns: 1fr;
    }

    .modal {
        border-radius: 8px 8px 0 0;
        max-height: 85vh;
    }
    .modal-header {
        padding: 16px;
    }
    .modal-body {
        padding: 16px;
    }
    .modal-footer {
        padding: 12px 16px;
    }

    .sets-table {
        font-size: 0.7rem;
    }
    .sets-table th,
    .sets-table td {
        padding: 4px;
    }

    .exercise-accordion-header {
        padding: 10px 12px;
        flex-wrap: wrap;
        gap: 4px;
    }
    .exercise-accordion-body {
        padding: 10px 12px;
    }

    .log-entry {
        padding: 10px 12px;
    }

    #toast {
        left: 16px;
        right: 16px;
        bottom: 16px;
    }
    .toast-msg {
        width: 100%;
    }
}

/* Touch-friendly inputs for mobile */
@media (pointer: coarse) {
    input,
    textarea,
    select,
    button {
        min-height: 44px;
    }
    .btn {
        min-height: 44px;
        padding: 12px 20px;
    }
    .btn-sm {
        min-height: 36px;
        padding: 8px 14px;
    }

    .exercise-accordion-header {
        min-height: 48px;
    }

    .nav-item {
        min-height: 52px;
    }
}

/* Prevent horizontal scroll on mobile */
html,
body {
    overflow-x: hidden;
}