* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
html {
    scroll-behavior: smooth;
}
body {
    font-family: Arial, Helvetica, sans-serif;
    color: #f4f4ff;
    line-height: 1.5;
    background:
        radial-gradient(circle at 10% 10%, #363078 0, transparent 28%),
        radial-gradient(circle at 90% 20%, #253f78 0, transparent 25%),
        radial-gradient(circle at 50% 100%, #35265e 0, transparent 30%),
        #11152b;
    min-height: 100vh;
}
.top-header {
    padding: 22px 7%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: rgba(17, 21, 43, 0.78);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(12px);
}
.brand {
    display: flex;
    align-items: center;
    gap: 13px;
}
.logo {
    width: 52px;
    height: 52px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 15px;
    background: linear-gradient(135deg, #7667ff, #a56cff);
    color: white;
    font-size: 18px;
    font-weight: bold;
    box-shadow: 0 8px 25px rgba(118, 103, 255, 0.3);
}
.brand h1 {
    font-size: 27px;
    letter-spacing: 0.5px;
}
.brand p {
    color: #aaaed0;
    font-size: 13px;
}
.header-date {
    padding: 8px 14px;
    border-radius: 20px;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: #d6d7ed;
    font-size: 13px;
}
.navbar {
    padding: 12px 7%;
    display: flex;
    gap: 8px;
    background: rgba(17, 21, 43, 0.65);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    backdrop-filter: blur(12px);
    overflow-x: auto;
}
.nav-btn {
    border: 1px solid transparent;
    background: transparent;
    color: #aaaed0;
    padding: 10px 17px;
    border-radius: 9px;
    font-size: 14px;
    cursor: pointer;
    white-space: nowrap;
    transition: 0.25s;
}
.nav-btn:hover {
    background: rgba(255, 255, 255, 0.08);
    color: white;
    transform: translateY(-2px);
}
.nav-btn.active {
    background: linear-gradient(135deg, #6658e8, #8767ed);
    color: white;
    box-shadow: 0 5px 18px rgba(102, 88, 232, 0.3);
}
.container {
    width: 88%;
    max-width: 1100px;
    margin: 32px auto;
}
.page-section {
    display: none;
    animation: showPage 0.3s ease;
}
.page-section.active-section {
    display: block;
}
@keyframes showPage {
    from {
        opacity: 0;
        transform: translateY(8px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}
.welcome-card {
    position: relative;
    overflow: hidden;
    padding: 32px;
    margin-bottom: 20px;
    border-radius: 20px;
    background:
        linear-gradient(
            135deg,
            rgba(105, 88, 232, 0.95),
            rgba(133, 91, 224, 0.88)
        );
    border: 1px solid rgba(255, 255, 255, 0.15);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.22);
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.welcome-card::before {
    content: "";
    position: absolute;
    width: 210px;
    height: 210px;
    right: -60px;
    top: -80px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.08);
}
.welcome-card::after {
    content: "";
    position: absolute;
    width: 100px;
    height: 100px;
    right: 120px;
    bottom: -55px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.06);
}
.welcome-card h2 {
    font-size: 27px;
    margin: 6px 0;
}
.welcome-card p:last-child {
    color: #eeeeff;
    font-size: 14px;
}
.welcome-card .small-title {
    color: #e4e0ff;
}
.welcome-icon {
    position: relative;
    z-index: 2;
    font-size: 62px;
    transform: rotate(-6deg);
    margin-right: 15px;
}
.small-title {
    color: #aaa0ff;
    font-size: 11px;
    font-weight: bold;
    letter-spacing: 1.5px;
}
.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 14px;
    margin-bottom: 20px;
}
.stat-card {
    padding: 18px;
    display: flex;
    align-items: center;
    gap: 12px;
    border-radius: 14px;
    background: rgba(255, 255, 255, 0.09);
    border: 1px solid rgba(255, 255, 255, 0.12);
    backdrop-filter: blur(10px);
    transition: 0.25s;
}
.stat-card:hover {
    transform: translateY(-5px);
    background: rgba(255, 255, 255, 0.13);
    box-shadow: 0 12px 25px rgba(0, 0, 0, 0.18);
}
.stat-icon {
    width: 43px;
    height: 43px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 11px;
    background: rgba(255, 255, 255, 0.1);
    font-size: 20px;
}
.stat-card p {
    color: #aaaed0;
    font-size: 12px;
}
.stat-card h3 {
    color: white;
    font-size: 24px;
}
.content-card {
    padding: 21px;
    margin-bottom: 18px;
    border-radius: 15px;
    background: rgba(255, 255, 255, 0.09);
    border: 1px solid rgba(255, 255, 255, 0.12);
    backdrop-filter: blur(12px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.12);
}
.content-card > h2 {
    margin-bottom: 15px;
    font-size: 18px;
}
.card-heading {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 15px;
}
.card-heading h2 {
    font-size: 18px;
}
.card-heading p {
    color: #999dbd;
    font-size: 12px;
}
.card-heading > span {
    padding: 5px 10px;
    border-radius: 20px;
    background: rgba(137, 119, 255, 0.2);
    color: #c2baff;
    font-size: 12px;
}
.progress-container {
    width: 100%;
    height: 13px;
    overflow: hidden;
    border-radius: 20px;
    background: rgba(255, 255, 255, 0.1);
}
.progress-bar {
    width: 0%;
    height: 100%;
    border-radius: 20px;
    background: linear-gradient(
        90deg,
        #6f5bea,
        #b16cff
    );
    transition: width 0.4s ease;
}
#progress-text {
    color: #b9adff;
    font-weight: bold;
}
.empty-state {
    padding: 30px 15px;
    text-align: center;
    color: #9296b5;
}
.empty-state div {
    margin-bottom: 8px;
    font-size: 34px;
}
.empty-state p {
    color: #d5d6e6;
    font-weight: bold;
}
.empty-state span {
    font-size: 12px;
}
.section-title {
    margin-bottom: 20px;
}
.section-title h2 {
    margin: 3px 0;
    font-size: 27px;
}
.section-title p:last-child {
    color: #999dbd;
    font-size: 14px;
}
.form-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr;
    gap: 14px;
    margin-bottom: 17px;
}
.form-group {
    display: flex;
    flex-direction: column;
    gap: 6px;
}
.form-group label {
    color: #d9daea;
    font-size: 13px;
    font-weight: bold;
}
.form-group input,
.form-group select {
    width: 100%;
    padding: 11px;
    border: 1px solid rgba(255, 255, 255, 0.13);
    border-radius: 8px;
    background: rgba(10, 13, 32, 0.55);
    color: white;
    font-size: 13px;
    transition: 0.2s;
}
.for-group input::placeholder {
    color: #777b9c;
}
.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: #8878ff;
    box-shadow: 0 0 0 3px rgba(136, 120, 255, 0.12);
}
.form-group select option {
    background: #202441;
    color: white;
}
.primary-btn {
    border: none;
    padding: 11px 18px;
    border-radius: 8px;
    background: linear-gradient(
        135deg,
        #6254e6,
        #8667ee
    );
    color: white;
    font-size: 13px;
    cursor: pointer;
    box-shadow: 0 5px 15px rgba(98, 84, 230, 0.25);
    transition: 0.2s;
}
.primary-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(98, 84, 230, 0.35);
}
.secondary-btn {
    padding: 10px 17px;
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.08);
    color: #ddddef;
    font-size: 13px;
    cursor: pointer;
    transition: 0.2s;
}
.secondary-btn:hover {
    background: rgba(255, 255, 255, 0.14);
    transform: translateY(-2px);
}
.filter-card {
    display: flex;
    align-items: center;
    gap: 7px;
    padding: 12px 15px;
    margin-bottom: 18px;
    border-radius: 11px;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: #aaaed0;
    font-size: 13px;
}
.filter-btn {
    border: none;
    padding: 7px 12px;
    border-radius: 7px;
    background: rgba(255, 255, 255, 0.08);
    color: #aaaed0;
    font-size: 12px;
    cursor: pointer;
    transition: 0.2s;
}
.filter-btn:hover {
    background: rgba(255, 255, 255, 0.15);
    color: white;
}
.filter-btn.active-filter {
    background: #6557e5;
    color: white;
}
.task-list {
    display: flex;
    flex-direction: column;
    gap: 9px;
}
.task-item {
    padding: 14px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    border-radius: 10px;
    background: rgba(10, 13, 32, 0.35);
    border: 1px solid rgba(255, 255, 255, 0.09);
    transition: 0.2s;
}
.task-item:hover {
    border-color: rgba(150, 135, 255, 0.4);
    transform: translateX(3px);
}
.task-info {
    flex: 1;
}
.task-info h3 {
    color: #eeeeff;
    font-size: 15px;
    margin-bottom: 3px;
}
.task-info p {
    color: #858aa9;
    font-size: 12px;
}
.task-actions {
    display: flex;
    gap: 6px;
}
.task-actions button {
    padding: 7px 10px;
    border: none;
    border-radius: 6px;
    font-size: 12px;
    cursor: pointer;
}
.complete-btn {
    background: rgba(65, 190, 110, 0.16);
    color: #7ee39c;
}
.complete-btn:hover {
    background: rgba(65, 190, 110, 0.27);
}
.delete-btn {
    background: rgba(230, 80, 90, 0.15);
    color: #ff999f;
}
.delete-btn:hover {
    background: rgba(230, 80, 90, 0.25);
}
.task-completed {
    opacity: 0.55;
}
.task-completed .task-info h3 {
    text-decoration: line-through;
}
.timer-card {
    max-width: 680px;
    margin: auto;
    padding: 40px 20px;
    text-align: center;
    border-radius: 18px;
    background: rgba(255, 255, 255, 0.09);
    border: 1px solid rgba(255, 255, 255, 0.13);
    backdrop-filter: blur(14px);
    box-shadow: 0 12px 35px rgba(0, 0, 0, 0.2);
}
.timer-circle {
    width: 220px;
    height: 220px;
    margin: 0 auto 28px;
    border-radius: 50%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: rgba(10, 13, 32, 0.45);
    border: 8px solid #6658e5;
    box-shadow:
        0 0 0 7px rgba(102, 88, 229, 0.13),
        0 0 35px rgba(102, 88, 229, 0.2);
}
#timer-display {
    color: white;
    font-size: 47px;
    font-weight: bold;
    letter-spacing: 2px;
}
.timer-circle small {
    margin-top: 2px;
    color: #858aa9;
    font-size: 10px;
    letter-spacing: 2px;
}
.timer-modes {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 7px;
    margin-bottom: 20px;
}
.mode-btn {
    padding: 8px 13px;
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 7px;
    background: rgba(255, 255, 255, 0.07);
    color: #a9acc7;
    font-size: 12px;
    cursor: pointer;
    transition: 0.2s;
}
.mode-btn:hover {
    background: rgba(255, 255, 255, 0.13);
    color: white;
}
.mode-btn.active-mode {
    background: #6557e5;
    border-color: #6557e5;
    color: white;
}
.timer-controls {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 7px;
}
.timer-status {
    margin-top: 18px;
    color: #9296b5;
    font-size: 13px;
}
.subject-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
}
.subject-card {
    position: relative;
    overflow: hidden;
    padding: 21px;
    border-radius: 14px;
    background: rgba(255, 255, 255, 0.09);
    border: 1px solid rgba(255, 255, 255, 0.12);
    backdrop-filter: blur(10px);
    transition: 0.25s;
}
.subject-card::after {
    content: "";
    position: absolute;
    width: 90px;
    height: 90px;
    right: -35px;
    bottom: -35px;
    border-radius: 50%;
    background: rgba(120, 103, 255, 0.12);
}
.subject-card:hover {
    transform: translateY(-6px);
    background: rgba(255, 255, 255, 0.13);
    border-color: rgba(150, 135, 255, 0.35);
    box-shadow: 0 12px 25px rgba(0, 0, 0, 0.18);
}
.subject-icon {
    width: 45px;
    height: 45px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 13px;
    border-radius: 11px;
    background: rgba(130, 110, 255, 0.15);
    font-size: 21px;
}
.subject-card h3 {
    color: #eeeeff;
    font-size: 17px;
    margin-bottom: 5px;
}
.subject-card p {
    color: #858aa9;
    font-size: 12px;
}
footer {
    margin-top: 40px;
    padding: 25px 15px;
    text-align: center;
    background: rgba(10, 13, 32, 0.45);
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    color: #777c9d;
    font-size: 12px;
}
footer p:first-child {
    margin-bottom: 4px;
}
@media (max-width: 850px) {
    .top-header {
        padding: 18px 4%;
    }ry
    .navbar {
        padding: 10px 4%;
    }
    .container {
        width: 92%;
    }
    .dashboard-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .form-grid {
        grid-template-columns: 1fr;
    }
    .subject-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}
@media (max-width: 520px) {
    .top-header {
        padding: 15px 4%;
    }
    .brand h1 {
        font-size: 22px;
    }
    .brand p {
        font-size: 11px;
    }
    .logo {
        width: 43px;
        height: 43px;
    }
    .header-date {
        display: none;
    }
    .container {
        width: 94%;
        margin: 22px auto;
    }
    .welcome-card {
        padding: 23px;
        border-radius: 15px;
    }
    .welcome-card h2 {
        font-size: 20px;
    }
    .welcome-icon {
        font-size: 40px;
        margin-right: 0;
    }
    .dashboard-grid {
        grid-template-columns: 1fr 1fr;
        gap: 9px;
    }
    .stat-card {
        padding: 13px;
    }
    .stat-icon {
        display: none;
    }
    .stat-card h3 {
        font-size: 20px;
    }
    .content-card {
        padding: 16px;
    }
    .section-title h2 {
        font-size: 23px;
    }
    .subject-grid {
        grid-template-columns: 1fr;
    }
    .timer-card {
        padding: 30px 14px;
    }
    .timer-circle {
        width: 185px;
        height: 185px;
    }
    #timer-display {
        font-size: 38px;
    }
    .task-item {
        flex-direction: column;
        align-items: flex-start;
    }
    .task-actions {
        width: 100%;
    }
    .task-actions button {
        flex: 1;
    }
    .filter-card {
        flex-wrap: wrap;
    }
    .filter-card span {
        width: 100%;
    }
}