/* --- Globals & Variables --- */
:root {
    --primary-color: #3498db;
    --primary-hover: #2980b9;
    --dark-bg: #1a1d21;
    --card-bg: #282c34;
    --text-primary: #e6e6e6;
    --text-secondary: #a0a0a0;
    --border-color: #3a3f47;
}

/* Base font-size on html allows for easy rem calculations (1rem = 16px) */
html {
    font-size: 100%; /* Default is 16px */
}

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--dark-bg);
    color: var(--text-primary);
    line-height: 1.6;
}

/*
================================================
DASHBOARD STYLES
================================================
*/

/* --- Main Layout --- */
.dashboard-container {
    max-width: 50rem; /* 800px */
    margin: 0 auto;
    padding: 1.25rem; /* 20px */
}

.dashboard-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.9375rem; /* 15px */
    margin-bottom: 1.875rem; /* 30px */
    flex-wrap: wrap; /* Allow wrapping on smaller screens */
    gap: 1rem;
}

.dashboard-header h1 {
    margin: 0;
    font-size: 2rem;
    color: var(--primary-color);
}

.profile-link {
    color: var(--text-primary);
}

/* --- Start Workout Section --- */
.start-workout-section {
    background-color: var(--card-bg);
    padding: 1.25rem; /* 20px */
    border-radius: 0.5rem; /* 8px */
    margin-bottom: 2.5rem; /* 40px */
    text-align: center;
}

#start-workout-form {
    display: flex;
    gap: 0.625rem; /* 10px */
    margin-top: 0.9375rem; /* 15px */
}

#start-workout-form input[type="text"] {
    flex-grow: 1;
    padding: 0.75rem; /* 12px */
    font-size: 1rem;
    background-color: #3a3f47;
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    border-radius: 0.3125rem; /* 5px */
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 0.75rem 1.25rem; /* 12px 20px */
    font-size: 1rem;
    font-weight: bold;
    border-radius: 0.3125rem; /* 5px */
    cursor: pointer;
    transition: background-color 0.2s ease-in-out;
}

.btn-primary:hover {
    background-color: var(--primary-hover);
}


/* --- Workout History & Cards --- */
.workout-card {
    display: block;
    background-color: var(--card-bg);
    border-radius: 0.5rem; /* 8px */
    margin-bottom: 1.25rem; /* 20px */
    text-decoration: none;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    transition: transform 0.2s ease-in-out, box-shadow 0.2s ease-in-out;
    position: relative;
}

.workout-card:hover {
    transform: translateY(-0.3125rem); /* -5px */
    box-shadow: 0 0.3125rem 0.9375rem rgba(0, 0, 0, 0.2); /* 0 5px 15px */
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    margin-bottom: 0.9375rem; /* 15px */
    gap: 0.5rem; /* Add gap for spacing */
    flex-wrap: wrap; /* Allow wrapping */
}

.card-header h3 {
    margin: 0;
    font-size: 1.4rem;
}

.card-header .workout-date {
    color: var(--text-secondary);
    font-size: 0.9rem;
    flex-shrink: 0; /* Prevent date from shrinking */
}

.card-content-link {
    display: block;
    text-decoration: none;
    color: inherit;
    padding: 1.25rem; /* 20px */
}

.btn-delete-workout {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0.3125rem; /* 5px */
    border-radius: 0.5rem; /* 8px */
    transition: background-color 0.2s, color 0.2s;
}

.btn-delete-workout:hover {
    background-color: #e74c3c;
    color: white;
}

.card-body p {
    margin-top: 0;
    font-weight: bold;
    color: var(--text-secondary);
}

.card-body ul {
    list-style-type: none;
    padding-left: 0;
    margin: 0;
}

.card-footer {
    border-top: 1px solid var(--border-color);
    margin-top: 0.9375rem; /* 15px */
    padding-top: 0.9375rem; /* 15px */
    display: flex;
    justify-content: space-between;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.no-workouts {
    text-align: center;
    padding: 2.5rem; /* 40px */
    background-color: var(--card-bg);
    border-radius: 0.5rem; /* 8px */
    color: var(--text-secondary);
}

/*
================================================
LOGIN PAGE STYLES
================================================
*/
.login-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 1.25rem; /* 20px */
}

.login-card {
    background-color: var(--card-bg);
    padding: 2.5rem 1.875rem; /* 40px 30px */
    border-radius: 0.5rem; /* 8px */
    width: 100%;
    max-width: 25rem; /* 400px */
    box-shadow: 0 0.625rem 1.5625rem rgba(0, 0, 0, 0.2); /* 0 10px 25px */
}

.login-header {
    text-align: center;
    margin-bottom: 1.875rem; /* 30px */
}

.login-header h1 {
    margin: 0 0 0.625rem; /* 10px */
    font-size: 2.5rem;
    color: var(--primary-color);
}

.login-header p {
    margin: 0;
    color: var(--text-secondary);
}

.form-group {
    margin-bottom: 1.25rem; /* 20px */
}

.form-group label {
    display: block;
    font-weight: bold;
    margin-bottom: 0.5rem; /* 8px */
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.form-group input {
    width: 100%;
    padding: 0.75rem; /* 12px */
    font-size: 1rem;
    color: var(--text-primary);
    background-color: #3a3f47;
    border: 1px solid var(--border-color);
    border-radius: 0.3125rem; /* 5px */
    box-sizing: border-box;
    transition: border-color 0.2s ease-in-out;
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.login-form .btn-primary {
    width: 100%;
    padding: 0.9375rem; /* 15px */
    font-size: 1.1rem;
    margin-top: 0.625rem; /* 10px */
}

.form-footer {
    text-align: center;
    margin-top: 1.875rem; /* 30px */
    font-size: 0.9rem;
}

.form-footer p {
    margin: 0;
    color: var(--text-secondary);
}

.form-footer a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: bold;
}

.form-footer a:hover {
    text-decoration: underline;
}

/*
================================================
ACTIVE WORKOUT SESSION STYLES
================================================
*/
.workout-session-container {
    max-width: 50rem; /* 800px */
    margin: 0 auto;
    padding: 1.25rem; /* 20px */
    padding-bottom: 6.25rem; /* 100px - Space for the FAB */
}

.session-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 0.9375rem; /* 15px */
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 1.25rem; /* 20px */
    flex-wrap: wrap; /* Allow items to wrap */
    gap: 1rem;
}

.back-link {
    color: var(--primary-color);
    text-decoration: none;
    font-size: 1rem;
}

.session-title {
    text-align: center;
    flex-grow: 1; /* Allow title to take available space */
}

.session-title h1 {
    margin: 0;
    font-size: 1.5rem;
}

#workout-timer {
    font-size: 1.2rem;
    color: var(--text-secondary);
    font-variant-numeric: tabular-nums;
}

.btn-danger {
    background-color: #e74c3c;
    color: white;
    border: none;
    padding: 0.625rem 0.9375rem; /* 10px 15px */
    border-radius: 0.3125rem; /* 5px */
    cursor: pointer;
    transition: background-color 0.2s ease;
}

.btn-danger:hover {
    background-color: #c0392b;
}

.exercise-group {
    background-color: var(--card-bg);
    border-radius: 0.5rem; /* 8px */
    padding: 0.9375rem; /* 15px */
    margin-bottom: 1.25rem; /* 20px */
}

.exercise-name {
    margin: 0 0 0.9375rem 0; /* 15px */
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.625rem; /* 10px */
    font-size: 1.3rem;
}

.set-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 0; /* 8px */
    border-bottom: 1px solid #3a3f47;
    gap: 1.25rem; /* 20px */
    flex-wrap: wrap; /* Allow wrapping on small screens */
}

.set-row > div:nth-child(1) {
    margin-right: auto;
}

.set-row:last-child {
    border-bottom: none;
}

.set-detail {
    font-size: 1.1rem;
    flex-grow: 1; /* Allow details to take space */
}

.set-rest {
    font-size: 0.9rem;
    color: var(--text-secondary);
    flex-shrink: 0; /* Prevent rest time from shrinking */
}

.set-actions {
    display: flex;
    gap: 0.625rem; /* 10px */
    flex-shrink: 0; /* Prevent buttons from shrinking */
}

.btn-delete-set, .btn-edit-set {
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 1.5rem;
    cursor: pointer;
}

.no-sets-placeholder {
    text-align: center;
    color: var(--text-secondary);
    padding: 3.125rem 1.25rem; /* 50px 20px */
    background-color: var(--card-bg);
    border-radius: 0.5rem; /* 8px */
}

/* Floating Action Button (FAB) */
.fab {
    position: fixed;
    bottom: 1.875rem; /* 30px */
    right: 1.875rem; /* 30px */
    width: 3.75rem; /* 60px */
    height: 3.75rem; /* 60px */
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 2rem;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: 0 0.25rem 0.75rem rgba(0, 0, 0, 0.3); /* 0 4px 12px */
    cursor: pointer;
    transition: background-color 0.2s ease, transform 0.2s ease;
    z-index: 999;
}

.fab:hover {
    background-color: var(--primary-hover);
    transform: scale(1.05);
}

/*
================================================
MODAL STYLES
================================================
*/
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    transition: opacity 0.3s ease;
    padding: 1rem;
}

.modal-overlay.hidden {
    opacity: 0;
    pointer-events: none;
}

.modal-content {
    background-color: var(--card-bg);
    padding: 1.5625rem; /* 25px */
    border-radius: 0.5rem; /* 8px */
    width: 100%;
    max-width: 31.25rem; /* 500px */
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.625rem; /* 10px */
    margin-bottom: 1.25rem; /* 20px */
}

.modal-header h2 {
    margin: 0;
    font-size: 1.5rem;
}

.close-button {
    background: none;
    border: none;
    font-size: 1.8rem;
    color: var(--text-secondary);
    cursor: pointer;
}

.form-row {
    display: flex;
    gap: 0.9375rem; /* 15px */
}

.form-row .form-group {
    flex: 1;
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 0.9375rem; /* 15px */
    margin-top: 1.25rem; /* 20px */
}

.btn-secondary {
    background-color: #4a5568;
    color: white;
    padding: 0.625rem 0.9375rem; /* 10px 15px */
    border: none;
    border-radius: 0.3125rem; /* 5px */
    cursor: pointer;
}

/*
================================================
RESPONSIVE DESIGN
================================================
*/
@media (max-width: 37.5em) {
    /* 600px */
    .dashboard-header {
        flex-direction: column;
        align-items: flex-start;
    }

    #start-workout-form {
        flex-direction: column;
    }

    .card-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .session-title h1 {
        font-size: 1.2rem;
    }

    .form-row {
        flex-direction: column;
    }

    .fab {
        bottom: 1.25rem; /* 20px */
        right: 1.25rem; /* 20px */
    }
}