* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --black: #000;
    --white: #fff;
}

html,
body {
    height: 100%;
}

body {
    font-family: 'Courier New', Courier, monospace;
    background-color: var(--black);
    color: var(--white);
    line-height: 1.4;
}

/* VIEWS */
.view {
    display: none;
    min-height: 100vh;
    flex-direction: column;
    padding: 1rem;
}

.view.active {
    display: flex;
}

/* Workout view needs fixed height for scroll behavior */
#view-workout.view.active {
    height: 100vh;
    max-height: 100vh;
    overflow: hidden;
}

/* HEADER */
header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 1rem;
    border-bottom: 2px solid var(--white);
    margin-bottom: 1.5rem;
}

header h1 {
    font-size: 1.5rem;
    font-weight: normal;
    letter-spacing: 0.2em;
}

/* MAIN */
main {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

/* FOOTER */
footer {
    padding-top: 1rem;
    border-top: 2px solid var(--white);
    margin-top: auto;
}

/* BUTTONS */
button {
    font-family: inherit;
    font-size: 1rem;
    cursor: pointer;
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

.btn-primary {
    width: 100%;
    padding: 1rem;
    background-color: var(--white);
    color: var(--black);
    border: 2px solid var(--white);
    font-weight: bold;
}

.btn-primary:active {
    background-color: var(--black);
    color: var(--white);
    transform: translateY(2px);
}

.btn-secondary {
    width: 100%;
    padding: 0.75rem;
    background-color: var(--black);
    color: var(--white);
    border: 2px solid var(--white);
}

.btn-secondary:active {
    background-color: var(--white);
    color: var(--black);
}

.btn-back {
    background: none;
    border: none;
    color: var(--white);
    font-size: 1rem;
    padding: 0.5rem 0;
}

/* STREAK DISPLAY */
.streak-display {
    text-align: center;
    padding: 2rem 0;
}

.streak-label {
    display: block;
    font-size: 0.875rem;
    letter-spacing: 0.2em;
    margin-bottom: 0.5rem;
}

.streak-count {
    display: block;
    font-size: 4rem;
    font-weight: bold;
    line-height: 1;
}

.streak-display.large .streak-count {
    font-size: 6rem;
}

/* DIFFICULTY SELECT */
.difficulty-select {
    text-align: center;
}

.difficulty-select label {
    display: block;
    font-size: 0.875rem;
    letter-spacing: 0.2em;
    margin-bottom: 0.75rem;
}

.difficulty-buttons {
    display: flex;
    gap: 0;
}

.btn-difficulty {
    flex: 1;
    padding: 0.75rem 0.5rem;
    background-color: var(--black);
    color: var(--white);
    border: 2px solid var(--white);
    font-size: 0.75rem;
}

.btn-difficulty+.btn-difficulty {
    border-left: none;
}

.btn-difficulty.active {
    background-color: var(--white);
    color: var(--black);
}

/* WORKOUT STATUS */
.workout-status {
    text-align: center;
    font-size: 0.875rem;
    min-height: 1.5rem;
}

.workout-status.completed {
    color: var(--white);
}

/* PROGRESS */
.progress-container {
    flex: 1;
    height: 1rem;
    border: 2px solid var(--white);
    margin: 0 1rem;
    position: relative;
    max-width: 200px;
}

.progress-bar {
    height: 100%;
    background-color: var(--white);
    width: 0%;
    transition: width 0.3s ease;
}

.progress {
    font-size: 1rem;
    letter-spacing: 0.1em;
}

/* EXERCISE DISPLAY */
.exercise-name {
    flex-shrink: 0;
    text-align: center;
    font-size: 1.25rem;
    font-weight: bold;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.exercise-images {
    flex-shrink: 0;
    text-align: center;
}

.exercise-images img {
    max-width: 100%;
    max-height: 200px;
    border: 2px solid var(--white);
    background-color: var(--black);
    filter: grayscale(100%) contrast(1.2) brightness(0.9);
}

.image-nav {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1rem;
    margin-top: 0.5rem;
}

.btn-img-nav {
    background: none;
    border: 2px solid var(--white);
    color: var(--white);
    width: 2.5rem;
    height: 2.5rem;
    font-size: 1rem;
}

.btn-img-nav:active {
    background-color: var(--white);
    color: var(--black);
}

#img-indicator {
    font-size: 0.875rem;
    min-width: 3rem;
    text-align: center;
}

/* EXERCISE REPS */
.exercise-reps {
    flex-shrink: 0;
    text-align: center;
    padding: 1rem 0;
    border: 2px solid var(--white);
}

.exercise-reps .reps-count {
    display: block;
    font-size: 3rem;
    font-weight: bold;
    line-height: 1;
}

.exercise-reps .reps-label {
    display: block;
    font-size: 0.875rem;
    letter-spacing: 0.2em;
    margin-top: 0.25rem;
}

/* EXERCISE INSTRUCTIONS */
.exercise-instructions {
    flex: 1;
    overflow-y: auto;
    min-height: 0;
    /* Critical for flexbox scroll to work */
    padding-bottom: 0.5rem;
}

.exercise-instructions h3 {
    font-size: 0.875rem;
    letter-spacing: 0.2em;
    margin-bottom: 0.75rem;
    font-weight: normal;
}

.exercise-instructions ol {
    padding-left: 1.5rem;
    font-size: 0.875rem;
}

.exercise-instructions li {
    margin-bottom: 0.5rem;
}

/* WORKOUT FOOTER */
.workout-footer {
    flex-shrink: 0;
    background-color: var(--black);
    padding: 1rem 0;
    border-top: 2px solid var(--white);
    margin-top: auto;
}

/* WORKOUT MAIN */
.workout-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    min-height: 0;
    /* Critical for nested flex scroll */
    gap: 1rem;
}

/* COMPLETE VIEW */
.complete-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    gap: 2rem;
}

.complete-main h1 {
    font-size: 1.5rem;
    letter-spacing: 0.2em;
}

.complete-main .btn-primary {
    width: auto;
    padding: 1rem 3rem;
}

/* HISTORY */
.history-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.history-item {
    border: 2px solid var(--white);
    padding: 1rem;
}

.history-item-date {
    font-size: 0.875rem;
    letter-spacing: 0.1em;
    margin-bottom: 0.5rem;
    display: block;
}

.history-item-exercises {
    font-size: 0.75rem;
    color: var(--white);
    opacity: 0.8;
}

.history-empty {
    text-align: center;
    padding: 2rem;
    font-size: 0.875rem;
    letter-spacing: 0.1em;
    display: none;
}

.history-empty.visible {
    display: block;
}

/* RESPONSIVE - Tablet and up */
@media (min-width: 600px) {
    .view {
        max-width: 500px;
        margin: 0 auto;
        padding: 2rem;
    }

    header h1 {
        font-size: 2rem;
    }

    .streak-count {
        font-size: 5rem;
    }

    .streak-display.large .streak-count {
        font-size: 8rem;
    }

    .btn-difficulty {
        font-size: 0.875rem;
        padding: 1rem;
    }

    .exercise-images img {
        max-height: 300px;
    }

    .exercise-name {
        font-size: 1.5rem;
    }

    .exercise-reps .reps-count {
        font-size: 4rem;
    }
}