/* =========================================================
   ASHU SUCCESS — PREMIUM EXAM UI
   Calm • Clean • Mobile-first • App-like
========================================================= */

/* ---------- ROOT THEME ---------- */
:root {
    --bg: #f6f8f7;
    --card: #ffffff;
    --accent: #6AA18A;
    --accent-soft: #9fcbb7;
    --accent-glow: #e6f2ee;

    --text-main: #2e2e2e;
    --text-light: #6f6f6f;

    --success: #4CAF50;
    --success-bg: #e9f6ec;

    --danger: #ff6f6f;
    --danger-bg: #ffecec;

    --radius: 16px;
    --shadow: 0 8px 24px rgba(0,0,0,0.08);
}

/* ---------- RESET ---------- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: "Segoe UI", system-ui, sans-serif;
    background: var(--bg);
    color: var(--text-main);
}

/* ---------- APP WRAPPER ---------- */
.app {
    max-width: 480px;
    margin: 0 auto;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* ---------- HEADER ---------- */
.header {
    background: var(--card);
    padding: 14px 18px;
    display: flex;
    align-items: center;
    gap: 12px;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 50;
}

.header h1 {
    font-size: 20px;
    font-weight: 700;
    color: var(--accent);
}

.hamburger {
    font-size: 24px;
    border: none;
    background: none;
    color: var(--accent);
    cursor: pointer;
}

/* ---------- SIDEBAR ---------- */
.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    width: 260px;
    height: 100%;
    background: var(--card);
    transform: translateX(-100%);
    transition: .35s ease;
    box-shadow: var(--shadow);
    padding-top: 70px;
    z-index: 100;
}

.sidebar.show {
    transform: translateX(0);
}

.sidebar ul {
    list-style: none;
}

.sidebar li {
    padding: 16px 20px;
    font-size: 17px;
    border-bottom: 1px solid #eef2f1;
    cursor: pointer;
}

.sidebar li:hover {
    background: var(--accent-soft);
    color: #fff;
}

/* ---------- MAIN ---------- */
main {
    flex: 1;
    padding: 16px;
}

/* ---------- CARD ---------- */
.card {
    background: var(--card);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 18px;
    margin-bottom: 16px;
}

/* ---------- QUESTION ---------- */
.question-text {
    font-size: 19px;
    line-height: 26px;
    margin-bottom: 16px;
}

/* ---------- OPTIONS ---------- */
.option {
    background: var(--card);
    border-radius: 14px;
    padding: 14px 16px;
    margin-bottom: 12px;
    box-shadow: 0 4px 14px rgba(0,0,0,0.07);
    cursor: pointer;
    transition: .2s ease;
    position: relative;
    overflow: hidden;
}

.option:hover {
    transform: translateY(-2px);
}

.option.correct {
    background: var(--success-bg);
    border: 2px solid var(--success);
    animation: glowGreen .4s ease;
}

.option.wrong {
    background: var(--danger-bg);
    border: 2px solid var(--danger);
    animation: shake .35s ease;
}

/* ---------- OPTION ANIMATIONS ---------- */
@keyframes shake {
    0% { transform: translateX(0); }
    25% { transform: translateX(-4px); }
    50% { transform: translateX(4px); }
    75% { transform: translateX(-4px); }
    100% { transform: translateX(0); }
}

@keyframes glowGreen {
    from { box-shadow: 0 0 0 rgba(76,175,80,0); }
    to { box-shadow: 0 0 18px rgba(76,175,80,0.45); }
}

/* ---------- BOTTOM EXPLANATION ---------- */
.explanation-panel {
    position: fixed;
    left: 0;
    right: 0;
    bottom: -100%;
    background: var(--card);
    border-radius: 22px 22px 0 0;
    box-shadow: 0 -10px 30px rgba(0,0,0,0.15);
    padding: 18px;
    transition: .4s ease;
    z-index: 200;
}

.explanation-panel.show {
    bottom: 0;
}

.explanation-panel h3 {
    color: var(--accent);
    margin-bottom: 6px;
}

.explanation-panel p {
    font-size: 15px;
    line-height: 23px;
    color: var(--text-main);
}

/* ---------- NAV BUTTONS ---------- */
.nav-btns {
    display: flex;
    gap: 12px;
    margin-top: 16px;
}

.nav-btn {
    flex: 1;
    padding: 14px;
    border-radius: 14px;
    border: none;
    font-size: 16px;
    background: var(--accent);
    color: #fff;
    cursor: pointer;
}

.nav-btn:disabled {
    background: #bfcfc8;
}

/* ---------- FOOTER ---------- */
.footer {
    text-align: center;
    padding: 16px;
    font-size: 14px;
    color: var(--text-light);
}

/* ---------- RIPPLE ---------- */
.option::after {
    content: "";
    position: absolute;
    width: 10px;
    height: 10px;
    background: rgba(0,0,0,0.1);
    border-radius: 50%;
    transform: scale(0);
    opacity: 0;
    pointer-events: none;
}

.option:active::after {
    transform: scale(25);
    opacity: 1;
    transition: transform .4s, opacity .6s;
}